ACTA
The
BOTANICA
Influence
of
NEERLANDICA,
of
Salts
Vol.
on
Tomato
2
1953
(4),
the
Exudation
Plants
BY
O.M.
Botanical
van
Laboratory,
Andel
University
(Received June
30th
of Groningen
1952)
CONTENTS
I.
II.
III.
Introduction
Material
and
Description
§
1.
§
2.
discussion
Influence of changes
the
on
Relation
449
methods
and
medium
§ 3.
445
in
the
453
experiments
osmotic
value
concentration
and the salt
of the
exudation
between salt
the
Influence of
of the
453
condition of the plant and
composition of the
medium
a.
Relation
b.
Concentration and composition
between composition
on
salt secretion
the
into
the
vessels
466
467
exudation
of the medium
and
the rate
of
exudation
to
4.
§
5.
§
6.
composition
of the
Influence
c.
§
the
467
of the
Stimulation of the exudation
Changes
in
the
salt
secretion
under
as
a
exudation
sap
in
relation
medium
of the
pH
of the
outer
the
470
solution
influence of
result of
on
the
exudation
478
480
sugar
alterations
in
the osmotic value
of
the medium
Potassium
a.
IV.
V.
the exudation
487
cyanide
487
2,4-Dinitrophenol
491
c.
Sodium
arsenate
492
d.
Sodium
fluoride
e.
lodo acetic
494
acid
Phenylurethane
495
.
.'
497
Periodicity
General
500
discussion
506
Summary
516
I.
In
on
b.
f.
§ 7.
485
The influence of inhibitors
1874 it
exudation
attributed
had
can
to
INTRODUCTION
already been pointed
be
the
exudation caused
distinguished,
occurrence
by
a
of
process
a
i.e.
out
the
by Sachs that
exudation
local pressure
localized in
the
two
which
in the stem,
roots.
types of
must
be
and
the
The first
phe-
446
O.
is
nomenon
also
from
shown
usually
has
trees,
been
M.
by
the
by
have been advanced
trees.
the
literature
By
as
(1920)
water
V.
to
his
if
mentioned
Blackman
assume
Sabinin
depend
As
on
adjacent
the
He
would be
this
to
in
sap
the
in
one
outer
neces-
to
importance,
no
a
and
(1941)
solution.
be
can
This
that of the
transport
in
b
=
k
The
medium
(P
—
P
x
e
P,
tissue
root
of P
an
should
),
the
must
calculated from
of
the
sap.
of
water,
Blackman
cottonplants
a
agreement
by Kohnlein
confirmed
rectilinear relation
supporting
the
the
by enhancing
held
true
if the
also.
roots
explain
emphasized,
somehow
since
be
Sabinin’s
converted
concentration
According
act
importance of
cannot
be
as
an
the
an
to
his
osmometer.
osmotic process
whole process
necessarily
a
of
certain
maintained between the
According to Priestxylem vessels would pro-
the external solution.
differentiating
osmotically
proved however,
in
exudation,
the exudation could
only
must
and
of cells
of
has
also
medium thus
reverse
this
of
rate
the difference between the osmotic
absorption
The
explained
the vessels
supply
that of
as
value of the
that
so
value
was
found that
these facts indicate
content
root
of exudation
rate
constant.
osmotic
of exudation and
sap
as
of the
the
the osmotic value of the sap,
P,
the
theory.
concentration difference
a
not
According
x
minute into
this
Although
vide
that it is
tissue.
root
vessels,
xylem
(1943) established
rate
within
been
the
the action
author
medium influenced the
Kramer
the
a
more
1929) stated like Sabinin that changes in the osmotic
(1915,
of
ley
In
permeable to
possibility which had
are
membrane. The values
with
agreed
value of the
solution in
that
so
pressed into the vessels.
cells
sides,
outer
gradient
considered
osmometer
exudation,
substances,
by Pfeffer.
of exudation,
rate
Eaton
the
the vessels would have
active
difference between the osmotic
the
of the
between the
for
con-
between the endodermis and
that the
the
to
has been
osmotic pressure.
increasing
value of the cells should be of
According
value of the
opinion
and
in exudation
of
the cells
water
osmotic
semipermeable
a
the
(1949)
in
Renner
idea.
Kramer
by
by
on
(1930).
of
more
value of the sap
formula
with
pressure.
(1930);
osmotically
osmotic value of the medium and k
this
root
Heyl’s paper
difference between the osmotic
a
(1925).
that
as
Many theories
of
and that of the medium. This view has been elaborated
being the
act
pressure.
(1921), however, pointed out,
the osmotic
osmometer.
b
an
there is
of
supposed,
been
the vessels
and
expand,
be
must
opinion
only
plants.
decapitated plants,
comprehensive review
a
to
transport
that cells
sucked in.
inner than
H.
sary
water
the
on
already
herbaceous
development
summarized
along gradients
thought
cannot
it
case
the
concentration
would be
the vessels
this
root
a
referred
are
been
movement
a
highest
water
has
authors
many
Priestley
the
of
of the
causes
recorded
although
on
(1952).
Arnold
sidered
second,
mainly
mentioned here. For
older literature the readers
recent
The
the exudation of
to
development
on
Some of them will be
ANDEL
investigated
We shall confine ourselves here
which is caused
VAN
active
into
material
that exudation
sap
(mainly
generally
sugar).
It
contains little
has
or
THE
no
INFLUENCE
but
all,
at
sugar
symplast
of the
tissue,
a
suction
of
Broyer
theless
in
of auxin
ence
Skoog,
When
and
the
on
Broyer
the
supposition
cesses
:
active
an
suction of
it.
This
provides
this author
they
proportional
and
that
of the
of
tivity
of the
by
0
and
internal
factors,
two
that
water,
Like
found
is
on
the
increase
that
this
The fact
rate
are
case
the
is,
at
the
till
the
a
and
the
sap
and thus
a
to
dilution
be
These
as
greater,
k
=
expected
the
A
change.
Sabinin’s
recti-
as
a
Like
theory.
of exudation
osmotic
value of the
O
—
b
m
measure
).
The
of
water
in
as
was
sap
factor
of
conduc-
the formula of
value of the
the osmotic value of the
Eaton,
and
sap
on
that
The latter
sap.
the
transport
by
medium
means
of
and
the
a
Nie
the
of the
by
a
more
They pointed
mentioned
theory
of substances from the medium.
of
water
an
has been decreased
medium,
the sap
must
into the vessels
by
become
continues
increase of the osmotic value of
rate
osmotic value of the medium
of exudation also.
decrease of
osmotic
Van
enhanced,
attained.
was
discrepancy with the
sap,
was
followed
was
means
permeation
Helder and
Arisz,
the
equilibrium
explained
the
of
increase of the
when
changes of
pro-
osmotic
rate
{O
of exudation
rate
before. This
an
of the
two
an
of exudation would be controlled
rate
value
new
assuming
as
of
of exudation caused
rate
to
of exudation
that when the
transport
same rate
Helder
value of the medium
sudden
a
concentrated if the secretion of salts
becomes
consist
vessels and
If the osmotic
enhancement of the osmotic value of the
more
by
1950) started
Arisz,
would
xylem
the osmotic
the
k and
could be
above without
found
plants Arisz,
tomato
exudation
to
not
k.
decrease of
gradual
had been
Helder and
solution: b
that if the osmotic
sudden
which
decrease of the
the
Renner
Sabinin,
Never-
of the influ-
account
on
the secretion of salt into the vessels and
on
influence of
explained.
m
In this
root
vessels.
(1938).
be considered
O
6
the
to
the
by metabolism,
the conclusion that the
to
is
(b
root
attributed
1948)
transport
difference between the
medium).
depends
out
the
and
salt
important support
to
has
root
place causing
demonstrated between the concentration of
external
k,
proportionality,
Sabinin,
the
retain the
of the
layers
take
must
especially
Nie,
xylem sap.
an
came
to
and
of exudation showed
could be
(a result
walls.
way,
Van
that
rate
through
status
cannot
outer
also
diffuse
probable that these phenomena could
the medium and the sudden
by
the stele
the
vessels
the exudation of
the
by
the
linear relation
cell
transport of salts
water
altered,
was
in
in
the
to
salts
this
(1951, c.f.
from
cells
Grossenbacher
investigating
Van Nie
of
(1938, c.f.
to
the lower metabolic
exudation process,
and
salts
447
PLANTS
Broyer
the exudation would be
on
entirely explained
and
TOMATO
(1942; Hoagland,
it very
they thought
OF
1949) supposed
controlled
are
and narcotics
oxygen
the
along
water
these processes
Since
be
of solutes
leakage
accumulation
to
Crafts
to
the
as
EXUDATION
the cells
pressure)
oxygen
Hoagland and
pressure
Owing
concentration
that
so
THE
salts.
mainly
the stele.
to
lower
salt
same
SALTS ON
and Stocking
Crafts, Currier,
the
OF
value
the osmotic value of the
the
rate
of the
sap
have
Conversely
of exudation
medium is
actually
are
lowered.
been found.
448
O.
The
exudation
for
plained
they
of the
Arisz,
the
of salts.
transport
salts
bility
that
In
in
in
authors
idea
into
Van
active
that
so
(1942)
transport.
always much
sensitive
the
consequence
place entirely
both
through
the
cells
value and
of
sur-
attract
substances
this
are
osmotic
the
is
osmotically
well
as
the exudation of
criticism
value
as
exudation
active
component.
Helder and
Van
on
plants,
tomato
of the
Overbeek’s
an
exter-
Arisz,
an
potassiumcyanide.
Only
Van
method of
Broyer
(1951) following Van Overobtaining wholly satisfactory results.
in
the
and salts that the
water
independently
and
the
active process,
to
osmotic
an
osmotic
the
succeed in
of the cells
osmotically
water
was
importance.
no
that the concentration of the
concluded from facts
(1952)
protoplasm
an
than
pressure.
not
take and secretion of
take
of
active
osmotically
found,
some
root
beek’s method did
Arnold
from
mention the view
highest osmotic
fully inhibit
higher
Nie however offered
determining
different
value between the
must
transport
This would indicate the presence of
was
is
the exudation
above,
we
distinguished
He
nal solution that would
the latter
water
they mentioned the possi-
which had been bound
water
active
of
transport
that of Priestley:
in
assume
vessels.
Overbeek
water
and
to
the
opinion.
salt
with
processes,
continually
the
the
less
should have the
enzymatic
decreases,
another
osmotic
expected.
reason
as
ex-
which
roots.
Now
medium.
or
the
difference of osmotic
a
hold
more
the vessels
down
pressed
sap.
of the
considered
(1939)
By
water.
broken
who
concurs
rounding
value
and the
the vessels
a
be
well
of the exudation sap
value
the vessels
the result of
as
Speidel
was
addition
The
would
as
opinion
the papers which have been discussed
some
His
sap
than
be
with
theory
exception.
one
transport
their
In
separated.
the
consider this
not
water
to
of
lower
could
observed,
were
be
to
cases
did
According
that the osmotic
of the
most
active
ANDEL
means
appeared
Van Nie
an
be
cannot
considered
sap
of
by
part
in
was
Helder and
occurrence
and
there
sap
VAN
which
phenomena,
greater
but
started
value
of
the
M.
from
would, according
the
to
however,
which could also
take
his
of
intensive
place against
a
should
salts.
opinion, take
considered
was
the up-
on
of water
transport
The
electroosmotically.
endodermis,
literature
transport
up
The
water
of
transport
him
by
be
to
concentration
gradient.
The
theory
position
of its
of Lundegardh
own.
importance for the
view
that the
This
( 1945,
1949,
exudation of wheat
transport
1950)
author considered
of
water
the
plants,
would
be
holds
more or
transport
but
of
less
salts
a
of
rejected his former
caused
by the difference
between the osmotic value of the sap and that of the external solution
(1940,
salts
1943).
into
process:
the
According
cells,
“Anion
to
should
his
opinion
be
the
respiration
permeability together build
centration level of salts in the
up-hill
reaction,
the
latter
and
up
the
root
the
anion
driving
a
respiration,
force
of
comparatively
steady
tissue,
state
the
pumping
exudation
high
exchange
of salts, viz.
the former
down-hill reaction”.
the
con-
representing
The
the
exudation
THE
of salts
salt
is
INFLUENCE
from
OF SALTS ON THE
the cells
is
given off from
be
to
the
EXUDATION
considered
cells,
as
there is
solution is
the
to
the
by
vascular
salt,
is
water
their
of
movement
is
water
value of the medium. This
expressed. This
impeded by
causes
salt is
out
when
in
inhibited
nected
off
active
smaller
a
In the third
in
the
carbondioxide
experiments,
the
investigation
The
we
salts
to
the
causing
a
Because of the
(Arisz,
logical
try
possibility of
in
Helder
the first
a
and
the process
has been
concentration of the
can
be
the
rate
investigated
of
in
changes
has
been
and
the
the
as
a
salt
salt
investigation
to
form
continuation
a
working hypothesis; that
transport of
on a
better
a
On
The effect of
proved
conclusions
more
transport of
it
seemed
to
From
may
the
be
other
drawn
hand
by
the
question
A
to
the salt
important.
the observed
be
in
changes
very
processes
(presence
be
should
of inhibitors
stimulated
in the
the
investigation
I
ningen.
wish
to
express
his
valuable advice
C.
Mees,
the
text
of this
II.
The
experiments
nobilis.
and
Nottingham,
English
made
was
salt
the
I
at
the
interest
am
to
second
secretion
taken in
salt
where
inhibited
will
hypothesis
experiments.
Laboratory
my
H.
work.
greatly indebted for his
for
point
extent
or
Professor Dr W.
at
Gro-
Arisz
To
Mr
correction
for
G.
of
paper.
MATERIAL AND
were
supply)
Botanical
the
composition
what
the facts obtained in the
my thanks
in
changes
the
medium). Our working
be discussed in connection with
The
(sugar
This
concerning
secretion and exudation would be influenced in circumstances,
active
of
understanding
directly by determining
constituted
xylem
water.
and salt
water
Lundegardh)
concentration of the exudation sap.
was
vessels.
this end the influence of several factors
solution
secretion.
Nie;
obtain
in various ways.
investigated
the
to
Van Nie.
osmotic
an
is
con-
vessels.
close relation between
investigated.
outer
exudation,
the
in
Van
place
the process of salt secretion. To
on
from
and
is
concentration difference between the
medium, which results
transport
to
Helder
sub-
secretion
together with carbon-
described below,
are
of Arisz,
inactive
the process
transferred
escape
with-
water
water
supposed that the exudation process is based
the vessels
and
sap
which
that
water
be
can
can
extra
proves
place
theory has been used
osmometer
have
respiration,
solution,
amount
changed.
not
which has been released
converted into
are
glycolysis.
produced
this
This so-called
fluoride, which
The
of
substances
processes.
sodium
by
Afterwards
besides
This is water,
the vessels.
to
synthetic
with
dioxide,
is
Lundegardh’s view,
to
given
osmotically
stances
adjacent
increase of the osmotic
an
the exudation of
of the salt solution, but the concentration of the solution is
According
osmotic
the cells
epithelium,
When
process.
in
vessels.
xylem
The
exuded
449
PLANTS
passive
a
change
a
value. The turgor is decreased and besides
salt
OF TOMATO
performed with
METHODS
tomato
plants and Sanchezia
450
M.
O.
Tomato
soil
from
and
pierced
2-3
meter
the
By
roots.
the
split afterwards,
that had
cm)
placed
were
about six weeks old
plants
particles
Ca(N0 ) 2
3
0.001
solution
6.2
and
diluted
solution
to
solution
without
In
the
house.
used
6-8
into
(dia-
into
of 1951
When
In
1
ml
ml of
1
that
about
is
about
saturated
a
case
A-Z
to
that
necessary,
water
tap
adjusted
was
in
had
nutrient
a
placed
were
in
enough
weeks
two
the
necessary
time between.
developed
last
the
the
cultures
water
If
week.
every
water
plants
During
in
of solution
iron tartrate,
solution.
Hoagland
0.0025 M.
used.
tap
the
M.KH2 PO„
solution
replaced
was
with
The disks
litre of
one
litre
one
hole
a
wooden disk.
a
0.0005
as
was
weeks the
experiments.
in
fixed
acid.
given
phosphate
summer
were
To
Hoagland
replenished
After
been
plants
,
sulfuric
was
nutrient solution
were
pots
litre
one
which had
of the
pH
to remove
cork,
and
4
water
a
contains 0.0025 M. KN0 3
1936).
The
weeks, iron
three
The
Broyer,
added.
was
by adding
every
M.MgS0
,
rinsed with
of
been bored
solution. This nutrient solution
(Hoagland
were
means
containing approximately
pots
on
VAN ANDEL
the
a
green-
roots
be
to
solutions
were
aerated.
In
1952 the
be illuminated
For
practical
the
during
Owing
time in
had
of
on
a
were
after
been
having
Thus it
could
possible
was
and
fell
to
illuminated
was
The
temperature
10°-18°C in the
the
room
could
plants
Usually they
nutrient
solution;
also
were
in
grown
on
plant
same
9
from
rose
in
24° C
to
dark, depending
in
a
winter,
in
when
it,
however,
the
5-6
during
two
a
or
The
green-house.
better
for
they
younger
usually
than the
green-house. They could
nutrient solution
could be used
in
placed
placed
normal
a
cultivated all the
be
not
were
stronger exudation and exuded for
a
often the
green-house
morning.
well under these conditions,
plants which
showed
the
growing in soil
developed
plants
in
green-house.
put
still
plants
that
green-house,
1950).
temperature.
lack
to
this
been
11
light period
the outside
on
the
reasons
till
evening
the
small
a
Veen,
der
plants under more constant conditions, at least in
lighting. Now, too, plants could be cultivated in winter.
the
to
obtained of
was
the
cultivate
to
regard
use
artificially (Van
weeks.
longer time,
even
be used
The
plants
that
so
three successive
days.
of
Cutlings
after
water
way
to
an
as
Sanchezia
tomato
plants.
develop. After
ordinary
this
green-house
1-3
ml
were
cut
of the
on
off
stem.
were
took
take
might
plants
the
depending
was
sap
to
It
that the
green-house
after 2—4 months
continued
nobilis
filled
pots
on
a
exuded
root
on
good
some
cm
experiment
put
system
the
two
on
were
was
with
In
developed
the
began
roots
Hoagland
tap
same
solution. In
sufficiently
artificially
lighted
months.
days,
an
place where
take
hour. The
sometimes
decapitated
to
a
had
season.
by these plants in
above the
Usually they
several weeks before
were
exude sap for several
which the
put
been fixed in the hole of a wooden disk in the
having
a
the first
the
same
week. The
roots
plant
plants
grow
out
evening before the day
place. Still
fixed in
the wooden
THE
disk
by
they
of
filled
through
the
Once
again
placed
was
tube could
The
the
if the
with
In
this
of
reading
and
it
1
tube
30
be
to
mm
s
vertical
It
and
outflowing
narrow
glass
If the rubber
account,
0.1
to
often
The
could
it
and
of
samples
longer
The
horizontal
of
the
the
taken
corresponded
mm
Arisz,
in
change
of
the
the
hole
by
diameter
again
vaseline.
short
time.
in
the
the
as
of
mm).
its
own
Leakage
tubes
capillary
till the osmotic
day
sample
means
on
some
a
rubber
0.4
i
was
sap
A
stump.
this
hole closed
vaseline,
same
the
on
with
in
of the
of
of the
value
preserved
were
changes
pricked into the
was
long,
the
up
done the
was
few
a
importance.
through
cm
elastic,
whose ends had been closed with
be determined. This
7
filled
sap
of
calibrated in
was
investigation
osmotic
hole
a
perceptible
was
the
tap.
the horizontal part of
course
great
the
(about
was
the
interruptions
One
mm.
precise
be
be
sufficiently
in
with
from
the stump
capillary
seldom occurred
a
follow in detail the
to
of exudation
sap
was
capillary tube
a
liquid.
that the
over
otherwise
put
renewed.
was
rubber tube.
through
by which the capillary had been fixed
the
usually
a
emptied. The tube
appeared
Nie
rate
then
of
minute.
one
were
solution
means
seconds,
of
possible
was
Right
plants
this
by blowing
estimated
was
Van
the
determined.
a
tube had
way
by
short
a
off every
of exudation could
Besides
the
off and
cut
was
within
replaced
of the meniscus of the sap
exudation.
Helder
rate
be
fixed
emptied
approximately
rate
of
two
The funnel could
one.
three-way glass tap. The horizontal part of
a
be
read
was
The
mm.
by
easily
movement
tube
minutes,
of
consisted
connected
part,
large
morning
stem
the stump and
tube
capillary
Next
piece of the
a
on
451
PLANTS
while the other served for the aeration.
them,
the funnel could
solution.
OF TOMATO
Into the wooden disk
pinchcock.
beside the
night before the experiment
Hoagland
a
of
one
EXUDATION
large funnel, whose outlet had been closed
on a
rubber tube with
a
The solution in
During
THE
SALTS ON
holes had been bored
smaller
on
OF
placed
were
means
be
INFLUENCE
value could
samples
had been
taken.
As
a
rule the
a
osmotic value of the sap
had been
plant
on
solution for half
a
an
hour
or
that when the circumstances had been altered,
more
the
before
rate
of exudation
reached
was
the osmotic value of the
was
less, it
(Van Andel
of this
osmometer
method
osmotic values
is
according
as
follows:
placed in
are
temperature of the
the
was
more
more.
It
appeared
it took 20 minutes
before
time,
or
again. When
constant
this
moment
1952).
The osmotic value of the sap
electric
took
sap
determined before
not
was
a
drops
was
to
if
determined
Baldes and
two
drops
by
means
Johnson.
of
changed
to
a
thermo-
principle
solutions of different
container saturated with
is
of
The
water
different
a
vapour,
The
extent.
resulting temperature difference between the drops, which is dependent
on
of
the
a
difference between their osmotic values,
thermocouple.
been
described in
Van
Andel
The
more
1952).
A
apparatus
that is
detail elsewhere
small
amount
is measured
used
(Baldes
of
liquid
for
this
and
—
by
means
purpose,
Johnson
±
0.01
ml
has
1939;
—
is
452
O.
required for
every
1 ml
the
time.
solutions
are
0.005 M.
KN0
be
must
5-6
takes
determinations
1
M.)
solution is referred
acid.
the
sap
error
the
the
to
or
sap
to
the
If for
indicated
in
the
to
these authors
in
be
to
less
was
external
instance
hereafter,
proved
a
solutions
were
a
solution
a
0.011
M.
sufficiently
than that of
approximately 0.001-0.002
was
of exudation and
rate
of the
conductivity
water
way,
made
a
M
concentrated
more
found.
was
addition
the
as
value of the
and is isotonic with
The determinations
When
In
be
can
values of
If the osmotic value of the solutions
acid.
hour,
with known solutions;
The osmotic
error
larger
relatively
the concentration of the solution of boric
as
0.05 M. boric acid solution the
a
than
A second
one
s
boric
made
more
up
about
between brackets in this paper.
(0.01
solution of boric
accurate.
be
can
used. The osmotic
that contains 0.005 M. KNO
meant
use
the osmotic value.
calibrated
were
is isotonic.
placed
3
is
to
that the determinations take
available,
are
always expressed
with which it
acid,
have
equilibrium with their surroundings, but when
thermocouple
was
sap
would
determination
solutions of boric acid
case
that determinations
so
one
time.
same
Every
this
be in
to
ANDEL
determining
method is,
complete
thermocouples
the
at
One
drops have
several
then,
of this
advantage
little
whereas
in other methods of
sap
VAN
determination,
one
and
now
M.
the factor k
in
the osmotic
the formula
value of the
determined
sometimes
was
Helder and
Arisz,
by
roots
Van
b=k
Nie.
According
(Oj,— O ) should
m
be
a
of its
measure
of exudation is
b
When in
magnitude.
the osmotic
medium O
is
b
ml ,
enhanced
=
k
t
(0
O
to
O
—
6
this
—
O
m2
). This applies
medium,
of the
the
to
when 0
has
6
subtracting the
—
—
2,
be
—
ffl2
whose
of
ml
a
osmotic
When sap
tration,
a
placed
was
25
ml
The
mined
to
amount
tube,
the stump
was
in
this
When the
For
topped
and
up
amount
with
to
a
so
to
O
2
.
)
ml
Now
find k
can
or
k
(O
=
decrease of the
So k
can
replaced
be
by
receive
nitrate
according
to
a
by
the
be
the
certain
k
=
2
now
—
by
O
)/
ml
of
rate
exu-
determined if
a
solution,
too
water
one.
end
concen-
right angles
of the tube
a
sap.
space
of time,
was
deter-
The
specific
gravity
the
proved
that have been calcu-
low.
to
of the
the
at
the concentration of the sap
had been
of sap
b
m2
another
twice
plant. Under the
the concentrations
little
concentrations
:
—
been bent
determining
glass distilled
phosphate
colorimetrically
phosphate
are
rate
of the
known.
of the
supposed
was
way,
(O m2
that had
placed
be somewhat greater,
lated
k
b
to
1
changed. We
yet
=
2
of sap, exuded in
by weighing.
gravity
b
value is
also
the
that
be collected for determinations of the salt
capillary
on
is
and
h
immediately after the change
calculated.
osmotic
value
was
container
specific
to
known
O
sap
decrease of b
a
moment
the sudden
b
conditions
When the osmotic value of the medium
not
—
b ). We know h
(éj
2
l
dation. O
O
can
solution
).
causes
m2,
(0(,
ml
of the
value
lt
certain
determined the container
a
was
volume of 25 ml. The nitrate
diluted
sap
were
phenoldisulphonic
determined
acid
method,
molybdenumblue method. Sometimes
the
THE
chloride
The
of
INFLUENCE
of the sap
pH
In
some
of
a
a
good
pH
the
thermo-electric
In
tables
a
but
During
The
not
pH
were
the
determined
by
means
solutions
by
means
showed
way,
calculated
deter-
from
of
means
the
higher
solution is
referred
only
the
be
in
H,
as
rise
a
The
were
cellar.
a
did
In
the
A-Z
or
contain
not
and
figures
solution
a
containing
aerated.
continually
The
the
throughout
bath
was
DISCUSSION
OF
water
a
was
temperature
day. The changes,
determinations of the osmotic
room, but then
kept
that
(±6).
to
solutions
performed
same
contain iron
M.
as
slight.
very
pH
that had been
used,
was
not
Solutions,
5.2.
to
but showed
could
III.
of
somewhat
were
done in the
temperature
by
was
sap
The solution did
experiments
quite constant,
however,
Volhardt.
to
determined
determined in this
Hoagland solution
a
amounted
a
experiments
were
453
PLANTS
according
was
concentrations
value
water.
mannitol
the
the
osmotic
Hoagland
salts
no
OF TOMATO
osmometer.
had
phosphate,
of the
concentrations,
with
distilled
The
solution.
of the solutions
conductivity
experiments
most
made with
EXUDATION
microtitration
by
and
The
agreement
of
THE
meter.
the
cases
Philoscoop.
minations
SALTS ON
determined
was
Beckman
a
OF
value
used, whose
constant.
DESCRIPTION AND
THE
EXPERIMENTS
§ 1.
Influence
of
changes
CONCENTRATION
1
Experiment
solution and
solution
which
had
exudation
mately
It
a
A
thirds
by
the
to
osmotic
value
THE
the
salt
Hoagland
one
been
the
of
till
At
solution:
till
it
time the
this
was
on
of exudation,
rate
immediately
after about 20
original value.
increase
the
mannitol,
constant,
constant.
Hoagland
put alternately
was
decreased.
minutes the
value
the
last
at
rate
just
began
before in
as
great
next
was
of exudation
as
of
approxi-
was
The mannitol solution
now
The
rate
conditions.
table
appears from
little
lower
when the
1
that the osmotic
outer
solution
did
value of the sap, 0
6,
not
contain
only mannitol. The product of osmotic value and
which is
30
and
EXUDATION
Hoagland
for
plant
ON
a
again
was
the
MEDIUM
isotonic solution of mannitol. When the
previously
immediately
such
1).
in
THE
decrease declined
two
replaced
(fig.
an
changed
was
of this
rate
on
OF
a
measure
seconds
decrease.
marized
in
the
hour. As
amount
expressed
The results
Osmotic
when
(S,
of the
table
plants
always
of several
as
given off
mm
similar
3
X
rate
to
M/30
experiments
the vessels every
sec.)
have
showed
been
a
sum-
1.
value and
only 0.01
of salt
was
but
any salt,
of exudation,
had
salt secretion
been
ml of sap
on
was
a
into
certain
the vessels
solution
required for
of the thermo-electric osmometer,
a
were
for
determined
about half
determination
by
the osmotic value of the sap
have been determined sooner, in fact
a
few
an
means
could
minutes after the medium
454
Fig.
O.
1.
Changes
in
the
exudation
and
isotonic solution lacking salts,
in
the
lower part
of the
M.
figure;
VAN
caused
vice
the
ANDEL
by
osmotic value
the salt secretion
in the
TABLE
Changes
of the
concentration
salt secretion
of the
medium.
and
an
Experiment
into
the
The
outer
solution
sap
in
the
is
by
middle
part
and
of the
salt
part.
as
result
a
were
of mannitol
from
a
change
a
Hoagland
solution
(M).
H
o„
0.041
0.037
0.040
0.82
0.57
0.82
0.040
0.039
0.041
0.82
0.55
0.82
0.048
0.041
0.048
0.96
0.54
0.96
0.042
0.038
0.041
0.81
0.54
0.96
0.044
0.038
0.047
0.66
0.33
0.69
0.044
0.035
0.042
o6
s
lb
o„
s
1c
Of,
s
Id
Of,
s
acid;
S
1.19
as
3
mm
an
represented
M
1a
boric
salt
H
s
M.
a
of exudation
Medium
o„
as
of the
upper
solutions
S
;is expressed
rate
1
vessels
isotonic solution
1
O
replacing
The
versa.
X
M
0.60
boric
acid/30
1.08
sec.
(H)
THE
had
been
before
sap
About
exuding
300-400
given off
times
did
not
as
considerably
if
a
any
no
after
The
of sap
the
In
that which
salt. This
had
of
salt
salt
of the
was
in the
same
isotonic
rapidly,
about
brium
became
smaller
The reduction of the
a
were
had
the
as
rate
Fig.
the salt
2.
secretion
Relation
half
or
solution
more
was
as
the
Every
same:
was
the
and
solution
they
at
solution but
decrease in
the
the
rate
of
of exudation
rate
became
the
salts.
solutions
The solutions
H).
decrease in
slowly,
of exudation
1
the
on
Hoagland
0.5 and
a
as
in the salt
all
investigated
the
than
more
much
very
attained.
of exudation
outer
altogether.
cease
contained
constant
of
state
less
equilisalt.
usually accompanied by
decrease of the osmotic value of the sap and therefore
in
amount
a
outer
by removing
as
mannitol.
always
rate
the
and
one
not
still
been
medium caused
The
new
1952).
by smaller decreases
well
proportion
was
the
of
sap
Andel,
mannitol solution for
(0; 0.1; 0.2;
afterwards
15 minutes.
a
reduced
as
place
that the salt secretion diminished
by adding
exudation. The behaviour
decreased
on
time
some
taken
Hoagland solution
the exudation
concentration of the
after
a
secretion
medium
experiment 2 (fig. 2)
been made
before
out
(Van
given off when the
equilibrium
different concentrations
had
was
took
which had
approximately
means
stayed
and
state
containing salts
flow
on
was
455
PLANTS
result of
changing the medium.
a
surface
were
that it
changes,
as
must
cut
plants
of exudation
rate
concentration
roots
OF TOMATO
salt could be taken up, but did
plant
the
however,
showed the
the vessels
as
hour exudation
were
in
to
large
contain
Even when
an
3
if the
appears that
of salt
two
mm
EXUDATION
appeared,
sap
reaches
THE
ON
in the vessels of the
concentration
It
OF SALTS
It
changed.
the
in the
INFLUENCE
by
a
decrease
too.
between
the
salt
concentration
exudation.
of the
medium and
the
rate
of
456
O.
It
a
change
has
been
of
the
rate
exudation.
in
the
mentioned in
In
this
which
level,
decrease
if
changed
Fig.
of
as
at
3.
the
of exudation
the
3
(fig. 3).
been
and
salt
of
(•------•
is
be
the
another
a
sudden decrease
suddenly increased by
Van
course:
which
of
the
a
lower-
a
gradual
a
will
Nie). What
value
to
value.
equilibrium
after
of
rate
gradual increase
previous
solution,
in
In the
left part
the osmotic
changing
above.
the
the salt
in
the
The
osmotic
with
the
part
happen
medium
are
of
the
effect
�)
in
medium
of
a
outer
figure;
data
we
can
the
on
was
the
simultaneous
the
The
osmotic
value
upper
from
part.
the
not
rate
of
change
solution.
calculated
the
see
medium, which is
concentration
of the
of the
figure
of the
salt
value
concentration
lower
of the
value
experimental data; •─•
the salt secretion
(� ─
and
causes
more
osmotic
secretion, compared
represented
the
outer
and
described
osmotic value and
a
in
change
take
of the
changes
time?
same
increase
by
can
a
changes
Helder and
(Arisz,
concentration
Influence
exudation
sap
an
has
exudation
in
rate
follows
salt
Experiment
effect
cause
the
lower than
is
of the osmotic value of the
now,
just
however
case
apparently always
that
introduction,
also
can
of exudation followed
Conversely the
ing
the
the osmotic value of the medium
rate
constant
ANDEL
of exudation.
osmotic value of the medium
enhancing
VAN
of the salt concentration of the medium
Changes
cause
M.
rate
of
of the
formula)
THE
altered in this
time
same
by replacing
of
mannitol,
A
further
the
this
the
the
plant
was
(sixth period
water
same
as
increased
in
as
alone,
in
fourth
The
(sixth
a
in
first
a
by
5).
this
gradual
solution
fig.
the
which
the salt
that the
4
but
after-
a
rate
finally attained
the
was
—
of the osmotic
value
together
demon-
the second
of exudation
of
is
now,
In
of mannitol
solution
the
just
part
(0.059
now
M.)
changed
mannitol and
salts
of exudation decreased
rate
The mannitol solution
This
now
caused
solution
shown in
a
was
sudden
rate
to
just
as
The
exudation,
most
decrease
in
fig.
4
whose osmotic
suddenly
but
then
decrease
experiment
replaced
was
The
a
lowest
first, but
(sixth
stayed
somewhat
afterwards
period).
value
was
at
the
in
When,
0.025
same
further.
the sudden increase
by
phenomenon
concentrated solution
at
M.,
a
conmore
already
(0.055 M.)
there
was
however,
the
rate
a
of
level; only after
On
the
5
alternately
sudden decrease followed
of
(third period)
con-
of exudation
concentration
of exudation is
Hoagland
a
and 4.
it
of the salt
rate
was
(fig. 4).
rate
solution.
of the
added
did
was
of exudation
instance
has been described
experiment
a
3
When
decrease.
exudation
was
and
M.) caused
increase
minutes
solution
a
however, the change
solutions of different concentrations.
exudation fell
10
meant
the osmotic
only
rate
change
by changes
eigth period):
of the
decrease
the
as
Hoagland
case
a
period,
gradually afterwards.
a
(0.018
known from
caused
a
period).
that when
to
and
gradual
mannitol
gradual
on
increase of the
diminished,
When,
by
equilibrium
value
appeared
course
In
centration
a
It
by
and
Another
(fig.
of
rate
before
decrease.
experiment
concentrated solution
more
(second
replaced
increase
of salts
the
solution the result
mannitol solution for
of
part
analogous
way
The
seventh
and increased
next
a
Hoagland solution (second
a
cases.
and fourth
a
—
osmotic
the first
period)
used
was
last
concentration of the
gradual
a
to
of the
had been attained
and
has been used.
in
At
which
water,
suddenly
was
in both
phenomenon
same
strated
in
as
The sudden
by
accompanied
was
another way.
of the
or
3
(fig.
attained
the salt
3).
now
part
the third
whether it
same
before.
as
fall.
addition
increase
altered; the changes of the
course
value
certain solution
a
the
at
gradually.
analogous
centration
of
added
was
and the last
of the osmotic
on
decrease
medium and
by the mannitol
of exudation
rate
the first
changed
solution
the sudden
been
experiment
value of the medium was
an
outer
hypertonic solution
a
sudden
a
distilled
on
and
followed
when mannitol
the
took
by
gradual
had
put
replaced
was
wards
In
457
concentration lowered
solution
more
value
of
was
period):
it
a
value
same
of exudation
the
the salt
value of the
then
medium
the
PLANTS
attained.
of the osmotic
next
TOMATO
the osmotic value of the
next
decrease followed
decrease
rate
OF
solution.
Hoagland
After
EXUDATION
of exudation showed
gradual
was
till
exudation,
THE
Hoagland
a
sudden and
a
ON
now
the osmotic
Lowering
caused
rate
more
level
constant
When
case.
enhanced but
again
was
SALTS
INFLUENCE OF
the
rate
Hoagland
of exudation
458
O.
was
followed
the osmotic
by
further
a
value of the
exudation. This
was
very
sap
done
M.
VAN ANDEL
just
table
Fig.
4.
2,
together
Comparison
of the medium
Fig.
5.
osmotic
Relation
value
of
on
with
between
the
rate
between
the
the
the
the
accompanied by changes in
experiments
results
course
the
are
of
Changes
salt
of
in the
the
of the
changes
exudation
osmotic
so
4
in
and
and
value
the
was
rate
of
changed.
summarized
experiments.
the
osmotic
absence
the
value
of salts.
change
of the
that water
simultaneously.
experiments
to
are
similar
presence
concentration,
affected
3 and
some
of various
effects
of exudation
medium.
these
determined in addition
before the external solution
The osmotic values of the sap in
in
In
slight increase.
was
in
medium
the
are
and salt transport
THE
OF
INFLUENCE
SALTS ON
THE
The osmotic value of the sap
the medium
Thus
the osmotic
increased, when the osmotic value
of the sap
value
showed
rise
a
of
M.
0.023
to
Van Nie.
osmotic value of the medium
removed
was
From
the
from
but
increased,
to
it
table 2
enhanced
was
with
the osmotic
that in
similar
4c)
the
sap
0.049 M.
to
osmotic
4 a,
the
and the salt
value of
the
cases
(experiment
the results
experiment
same
0.022 M.
to
to
increased from
was
extent, that is from 0.042 M.
unaltered
stay
from 0.043 M.
agrees
When in the
solution,
outer
appears
also
can
sap
the
smaller
a
4). This
(experiment
M.
Helder and
Arisz,
of
being changed.
not
0.053 M. when the osmotic value of the medium
0.012
459
PLANTS
OF TOMATO
the salt concentration
enhanced,
was
EXUDATION
value
of
decrease
or
somewhat.
When
the
osmotic
value
eighth
In
osmotic
extent
same
and
concentrated solution of mannitol
a
the
solution
all
can
did
that
a
solution
Hoagland
less
in
off
given
was
salt.
If
we
the
to
want
the
salt
influence of
secretion.
Only
secretion
salt
In
the
a
mannitol,
the
solution
gradual
in
3
fig.
that these
since
of
the
less
was
a
correct
medium
plants
salt
rate
in
the
on
salt
the
on
the
just
used.
be
can
given
by
a
off
The
seen
the
to
hypertonic
of exudation
the
(fourth
are
as
was
replaced
of the
4
differ
idea about
were
nobilis,
decrease,
has
of
the
5.
phenomena
sucrose
outer
values
solutions
outer
get
tomato
and
the
the
value of the medium
Here also
4c).
more
How
of exudation
rate
concentration
in
change
are
we
possible
formula
changed
to
to
the
same
was
that
way
period).
not
due
to
a
effect
same
specific
(experi-
causes
b
have
to
medium.
depends
value
influenced
The way
the
on
of the
be
extent
by changes
in which
the
in
rate
of the simultaneous
medium.
the
phenomena set forth above?
theory of Arisz, Helder and Van Nie there
for
change
a
m
)
of the
either
conductivity of the
the osmotic
proves
explain
b=k{O —O
either the
us
of the
the osmotic
According
Let
sixth
4,
reckon with
must
the
to
Sanchezia
The sudden fall
further
of exudation is
is
to
same
14).
salt
must
outer
not
value of the medium alone
section
described above
Hoagland
a
in
obtained with
be observed
of
Thus
two
concentration
discussed
demonstrated
may
ment
the
by
been
action
be
of mannitol.
followed
It
salt
(experiment
when
solution
has
will
were
from table 2
vessels
the
experiment
results
same
the
but
when
compare
we
when
The influence of the osmotic
secretion.
for
(experiment
vessels,
to
different circumstances
enhancement of the osmotic
an
reduce
salt
contain
not
merely in salt concentration is it possible
the
used
was
always increased,
sap
solution of salt and mannitol of the
the
replaced
the salt secretion
fact,
when
as
of the
period).
cases
solution
value
value of the sap
k
roots
rate
can
for
in the
of exudation.
change
water
vessels
or
or
O
—
b
are
In Sabinin’s
O
so
m,
that
the difference between
and
that of the medium
altered.
first consider the former
changed k
can
be determined
possibility.
by dividing
When the
the sudden
outer
solution
change
in the
460
O.
M.
M(0. 16M)0.035
H
changes
by
M(0. 56 0.0600.074 0.44
1.40
M(0. 73M)0.061 0.080 M(0. 20M) 0.030 0.035
0.51
0.36
+
H
0.042 0.058 1.26
M(0. 59M)
0.056 0.058 0.36
M(0. 31M) 0.048 0.062
H
0.0420.050
H
H
0.046 0.057 1.60
water
0.86
osmotic
salt
TABLE
0.043 0.040
of
value
2
0.85
H
the
secretion
ANDEL
M)
simultaneousmedium
caused
VAN
the
1.43
0.047 0.052 1.66
distil ,
H
M.
0.022 0.027 0.51
0.035 0.043 0.77
H
0.036 0.062
1.00
H
0.049 0.075 1.27
the
and
sap
the
of
to
and
M(0. 2 M) 0.049 0.037 M(0. 49M)0.053 0.067 M(0. 20M)0.033 0.030 M(0. 31M) 0.036 0.051 M(0. 37M) 0.059 0.067 amounted
0.64
conetraion
H
value salt
osmotic
the
in
Changes
0.1-0.13
the
of
0.043 0.043
1.37
0.58
H
0.049 0.055 1.71
0.36
H
0.027 0.035 0.46
0.36
H
0.036 0.059
1.03
0.78
H
0.048 0.071 1.32
solution
M)
M(0. 23M)0.053 0.054
0.99
+
H+M(0. 56
(H)
0.067 0.076 0.92
H+M(0.27M) H+M(0.29M) H+M(0.37M)
0.049 0.059 1.73
H
0.043 0.072 0.92
0.041 0.041 0.35
0.064 0.083
1.28
0.050 0.070
1.34
Hoagland
H
H
0.043 0.046
H
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u
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d
osmotic
The
THE
INFLUENCE OF SALTS ON
rate
of exudation
(see
Material
In
the
plant
minutes
The
so
isotonic
Afterwards,
to
as
solutions
on
times
a
this
concentrated
follow
way
Min.
that
so
for
Mannitol
sol.
Mannitol
sol.
(0.011 M)
after
the
k
Hoagland
Five
the
value
exudation had
It
sidering
motic
the
3
by
the
lack
we
must
the values of k
when
3
30
sec
land
when
a
solution
changed
for
mm/30
7.4
the
sec.
40
13.8
mm/30
sec.
423
5
17.4
mm/30
sec.
423
19.4
mm/30
sec.
423
on
rate
changed
k is
(third
sec.
We
can
The latter
values of k
and
when
the
medium
a
os-
be
was
compared
been used.
suddenly
of
7.8
by
replaced
solution
sudden
conclude from
the
any
con-
phenomenon,
can
value have
osmotic
solution
between
to
by Arisz, Helder and Van Nie,
reason
TABLE
Relation
changed
not
of
time.
with the influence of the
factor.
of exudation increased
Hoagland
rate
reckon
this
same
period)
that
alter-
no
the
although
at
443
in the medium. When
solution of salts and mannitol
a
experiment
that
too,
changed
463
of salts
been observed
solutions of the
experiment
mm/30
considerably
is demonstrated in table 3. For this
only
14.6
yet perceptible,
was
experiment
extent
already
30
solutions had been
outer
of k
value of the medium
which had
sec.
30
....
already
from
appears
considerable
mm/30
....
(0.011 M)
457
sec.
17.4
....
minutes after
in
ation
sol.
20.4 mm/30
5
....
Hcagland sol. (0.011 M)
of
exudation
....
(0.012 M)
of k.
of the
....
(0.012 Ml
few
a
below.
change
(0.012 M)
Then
for
the calculation
Rate
sol.
plant
conditions.
solution
medium
Mannitol
cannot
we
of exudation of this
rate
under various
more
Medium
Hoagland sol.
461
PLANTS
value of the medium
used
were
the
obtain the data necessary
found in
values
OF TOMATO
in the osmotic
however,
different
at
placed
was
EXUDATION
methods).
1
determined
was
by the change
and
experiment
calculate k.
THE
by
a
In
mm/
Hoag-
mannitol
was
increase amounted
to
these data that the values of
3
osmotic value
H
H(0.013 M)
of the
M
+
medium
and
k
H(0.013 M)
(0.037 M)
4d
k
516
medium
H(0.012 M)
432
H
516
M
+
H
H
(0.012 M)
(0.033 M)
15c
k
411
k in the second and fourth
in
the osmotic
cases,
while
differed
In
the
by
some
rate
period
368
the
rates
of exudation
being
of exudation in
5
mm/30 sec.
experiments k certainly
was
proved
433
nearly the
the condition
changed.
to
be
Glucose
356
only slightly different
are
value of the medium
+
(0.032 M)
In
these
the
same
of
change
in
both
equilibrium
cases
however
different under similar
con-
462
ditions
be
as
times. For
this
of
caused
conductivity
water
medium. Periodical
In this
it
case
other
in
solution
The osmotic
of
transport
transport is
the
1
value
osmotic
less salt is
given off
there does
the
of
value
the
lowered.
An
of the sap
the
that is
should
the
period
salt
the
3,
4
to
nought
is
and 5
same
the
every
A
reduced
experiment
decrease
vessels
at
sap
it
does
is
all.
rate
not
of the
is
water
case
difference
solution
outer
In
too.
1
table
value of the sap
rate
at
and
value
O
—
O
m
the
last
is
a
so
water.
the
rate
In this
slowly.
It is
case
salt
possible
is
to
little. As
as
the salt
given
that less
was
of this
off from
is
of exudation is
now,
result
a
the vessels
a
to
slightly
will be diluted
The osmotic
that is
that
lowered
only
carried
causes
3,
experiments
been
equilibrium
given off
flow of
and
Salt
stronger mannitol solution
very
secretion
value of the medium
new
salt
When how-
In
in the vessels
sap.
the
always decrease
but
changing
sap
value
the decrease in
salt
of exudation slows down
the
when
medium has
should
means
(experiment
of the sap.
secretion
b
At
more
the
)
continue
to
eighth period).
of
O
m
were
lowered
not
—
was
time
same
The osmotic
solution of mannitol would
which salt
by
=k{O b
experimentally
was
value of the
now.
b
water.
medium
the
at
the relation between
the salt
so
of the
secretion
1, in which the osmotic
The
transport.
carried off
of
the reduction
considerably,
alter any
a
and
transport,
removed
Addition of
transport
4, second
diluted
slowly
between the
which
the
falls
was
t
the osmotic
the osmotic
in
more
formula
the
concentration of the
time,
extent.
altered
in
salt
water
in
in
solution
outer
water
change
value
concentration
m
of the
given off, it is
of
secretion is
not
this
transported
vessels is diluted
that of the
now
In
water
in the
sap
the osmotic
This has been found
reduce the
as
of
Consequently
and
sap
lowered.
conditions the osmotic
salt
experiment
;
transport
controls
the
The
unaltered in
remained
amount
increase if the salt
now
rate.
same
less
ever
water
medium;
concentration of the
was
of exudation
rate
of O
increase
concentration of the
second
solution
outer
of the
the
some
reduction of b,
at
The
vessels.
value of the
the salt
by
decrease.
experiments
the other
enhanced and in
a
the
to
decreased.
actually
In
the relation between the
on
concentration
that under such
see,
out
2).
must
the
so
be left
difference between the
the osmotic
on
immediately change.
not
osmotic
diminished and
can
depends
the vessels, while the
to
can
the
7.
medium.
influenced
and
in
section
of exudation would be
rate
transfer of salts
between the osmotic value
we
that the
the
while the salt
1,
experiment
and
is
(table
in
to
of the
of exudation. The
rate
in the osmotic
dependent
of salts
solution
The
and
and the
directly
discussed
in the
changes
value of the sap
water
transport
outer
of
change
a
the vessels
be
rather
are
changes
as
absence of salts
or
presence
will
changes
than
that alterations in the factor k
cause
the result of
as
these
reason
of k
mentioned was,
possibility
altered
the
as
ANDEL
periodicity
the
by
changes
appears
of consideration
VAN
phenomena
various
at
considered
is
M.
O.
the
established
and
that
at
value of the
constant too.
greater decrease
off
to
the vessels
salt is
removed
THE
OF
INFLUENCE
SALTS ON
unit of time than has been
per
become
and
the transport of salts
brium
when
has
been
the
only
the
salt
The
tions
the
osmotic
the
circumstances
from
different effect
of
rate
caused
been
exudation
transport
of
is
water
value of the medium
is
an
as
equilithat
to
in
changed;
reduced
but
decrease,
by weak and
both
compared with
be
reduced
the
to
the
the
by
in the
the
of exudation will
relation between
neither increase
in
changes
of
solution
the
now
way:
the
osmotic
the salt secretion is reduced
as
water
the osmotic value of the sap
altered and
same
solution. The
outer
The
mannitol
a
in
5.
enhancement of
extent
same
and
by
explained
concentrated solu-
more
4
fig.
caused
are
can
because of the lack of salts
rate
is
water
till
up
must
taken up
analogous
case
medium
shown in
that
moderate concentration
not
of
a
is
secretion.
of mannitol has
must
the
of
speeded
meet
we
the sap
water
more
463
PLANTS
the vessels and
to
the vessels is
value
transport
OF TOMATO
consequence
Here
attained.
EXUDATION
given off
In
concentrated.
more
THE
salt
transport
remains the
decrease
nor
of exudation
rate
and
same.
is
The
the sudden
after
change.
It will be
from
the salt
that
increases
case
well
as
—
more
the decrease in
as
The
will
sap
as
increase
in
the salt
the
as
this
only
value this is
depends
different
are
—
at
occurs
for
one
on
also
a
after
show
or
water
a
further
mean
a
3
(sixth
Thus
by
can
in
changes
In
as
must
be
period)
explain
the
cause
an
of
sudden
change
change
only
—
value of the medium. What
increase in the
In
secretion.
changes
at
to
the
the
osmotic
the result of
addition
can
the
rate
and these
k,
the
in the
the salt
water
consequence
the
the sap
is
of exudation decreases.
rate
same
replacement
concen-
transport,
way
as
when
of
only
Hoagland
a
the
demonstrated
solution
water.
we
medium
than
the
the salt secretion and the value of
reduction of the salt
distilled
greater.
plant.
.result the exudation
fig.
by
m
increase.
osmotic value of the medium has been lowered. This is
in
less
or
O
according
and salt secretion
transport
certain osmotic
more
—
greater
made
the sudden rise
a
O,,
becomes
water
is
similar
a
—
concentrated
more
transport
Thus
diluted, and after the initial increase
As
vessels
decrease in the osmotic value and
tration of the medium
but
that
or
which would
each
A simultaneous
water
decrease
happen
extent
same
in
secretion.
either
It will seldom
to
The flow of
dilute
more
in
explained
the
to
the osmotic value in the medium is
become
exudation will
be
can
resulting
simultaneous increase in
a
given off
salt.
of exudation
rate
value and
is
water
more
whether the increase
to
changes in the
concentration of the medium
In
way.
clear that the
decrease in the osmotic
a
changes
value
changes
osmotic
in
effect
in
and
the
the
water
of the
of exudation caused
rate
salt
concentration of the
transport
outer
and
salt secretion.
solution,
a
salt effect
observed.
If the
concentration of the
salt
motic value is
decrease,
as
not
much
enhanced,
medium is
lowered while
the
os-
the osmotic value of the
sap should
the solution in the vessels
becomes
more
dilute.
It has
464
O.
been
pointed
usually
sap
solution
mannitol and salt
has
been
found
ANDEL
alone
mannitol
(table
An
2).
increase
an
actual
In
when
weak
a
value
of the sap,
speculation
our
pointed
as
value
showed
sap
that
k
be
to
was
supposed
we
increases.
(table
These
This could
the values
an
This
the
the osmotic
perhaps be
the
When b
and
k
that there
so
and
3
from
4 d. On
0.048 M
and
water
are
for
table
2
(O
fc
the
un-
transport
known
we
can
should
roots
theor.). The increase
in this
might be explained
in
way
a
where the differences between
instance,
was
on
a
the
is
theory
exceed
not
demonstrated
solution of mannitol 0.059 M
a
in
clearly
more
solution the osmotic value of the sap
Hoagland
a
(fourth
period)
M
considerable increase. Osmotic values of 0.071
M would be
0.067
in
of
cause
the
has
value of
determination.
deviation
experiment
was
a
increase of the
those that have been calculated do
found and
of
error
stated
are
value of the sap
experiment
cases;
the
for
changed
remain unaltered. Now it
to
diminishes if
k
decrease of k.
a
values
the osmotic
few
was
1).
decrease instead
a
was
calculate what osmotic value the sap in the vessels of the
in
both
value
expected.
increase in the osmotic value of the sap,
being impeded by
have.
outer
of the medium
osmotic
solution of mannitol
just
already
out
the medium
expected
the
contained
decrease of the osmotic
enhancement of its
an
it
concentrated solutions of mannitol caused
osmotic
been
when
solution.
Hoagland
More
smaller when
was
than
Conversely the osmotic value of the
of
the osmotic value of the
cases
increase
only when the salt concentration
without
lowered
the
though
contained
VAN
that in such
already
out
rose,
M.
expected according
the
to
calculation; that is
decrease.
a
Helder and
Arisz,
osmotic
of the
value
calculated from
thing
be
can
Van Nie
exudation
formula.
the
noticed in
the
also found
and
sap
The
former
example
difference between the
a
the
was
given
that
value
too
above
had
which will be discussed
an
osmotic
M
0.037
but then
Of
the
found
was
The
pointed
experimental
value
of the
explain
have
the
pointed
osmotic
flowing sap.
sap
been
out
errors
k,
which
already
could
outer
based
solutions.
the difference
in
4
period),
occurs
in
a
involved. An
error
it
experiment
is
4,
can
error
be
as
of the
improbable
the
3,
small.
well
as
the determination
However
2)
value of
very
value of the sap
on
also
(table
experiment
the difference is
be
can
sap
experiment
(fourth
thing
same
is
in
this
must
that
being
0.001-0.002 M.
We
in
M
the determination of the osmotic
would
only
has
of 0.049
of the exudation
Thus
expected.
calculated.
being
as
be
to
calculation of
osmotic
this
is
value
course
made in
in
than
higher
value
that the osmotic
however,
state
be
Ad).
for
We
extensively later.
more
same
(experiment
Arisz, Helder and Van Nie mentioned several explanations
phenomenon,
been
The
small.
was
In
0.061
to
the
fact,
that it
value of the sap
experiment
M
4a
(eighth period)
in
takes
the
the fact
some
roots
are
time before
shown in
that the osmotic
changes
the
out-
value of the
while the osmotic value of the medium
THE
0.073
was
only
can
OF
INFLUENCE
be
M, might
for
account
value of the
SALTS ON
low
or
EXUDATION
in this
explained
too
medium,
THE
high
too
of
case
small
a
decrease in its
its
changes
that
as
cannot
We
in
of
case
all
the
the
the
M.
0.027
A
salt secretion
of
port
be
salt
As
concluded
from
salt
was
19.4
the salt
the vessels
to
must
we
in the salt secretion
took
the
given off
from
the
can
taken
be
salt
that
must
the process
components. Salt is
even
when
no
from the
outer
the
uptake,
part
expression
achieves
solution
the vessels.
to
other
0.013
M
that
the
least
at
trans-
%, it
must
half.
one
flow
water
considerably
that
of the salt
magnitude
less
as
secretion
the whole
soon
much
salt
as
at
reduction
the salt had
minute after
one
is
will
called
salt
the vessels is
the medium.
continues,
come
more
be
can
salt
taken
is
up
can
be
“tissue
is
the transfer of salts,
tissue.
“salt
at
This
the
salt
consists
tissue
is
smaller
a
creates
secretion”
from
when
up
some
transported rapidly,
part
henceforth
secretion
although
the
carried
partially held
However
to
the
no
still
rate.
the
im-
of
two
vessels,
from the medium. In addition salt taken
up
This
from
called
we
continually
salt is taken
directly,
salt
indicates
solution. Likewise
to
from
up
the exudation
necessary
pression
50
3
after
medium.
off and
given
The
to
soon
sec
than the
extent
decreased
place within
Thus the secretion of salt
salt
mm/30
almost
by
as
immediately after the change of the
the vessels
to
larger
one
true
experiment
This shows
conclude that almost
outer
In
medium from
followed.
a
given
solution is
changes
sudden reduction of the
the
Considering
been removed from
apparently
secretion
decrease followed,
given off
equilibrium,
to
is
holds
same
outer
11.2
to
medium,
salt
decrease within
a
altered.
reduced
was
spite of the large
gradual
solutions.
outer
the
decrease
the latter
that
that in
further
up
shows
medium is
have diminished
must
that less
concentration of the
decreased
gradual
more
water.
The fact
a
of the fact
change of the medium; the
the
of exudation
rate
from this that the salt secretion
of exudation
rate
of the
however,
concentration of the
of exudation
concentration of the
salt
hypothesis,
decrease of the
result
the
rate
increase when
conditions
phenomena.
as
The
ways:
consider the action
working
decrease of the salt
considered
two
expectation,
our
observed under
we
enhancement of the osmotic value of the
an
to
This
to
a
outflowing
high.
too
if
explained
for
a
opposite
of exudation
osmometer.
enhanced. It follows
the
be
can
minutes after
two
as
become
can
rate
an
the vessels.
to
for
of
account
should be
or
the
direction
a
have demonstrated that the
the
off
in
forth above
set
root
changes in
value
absolute
The
as
value of the medium and
salt concentration the osmotic value of the
the osmotic value
and
of the osmotic
value
conclude that in the
differ from the value calculated from the formula in
can
sap
increase
when the osmotic
must
we
465
PLANTS
increase of the osmotic
an
value
a
of the medium has been decreased. So
TOMATO
But this “retardation”
way.
value after
a
OF
of the salt
be
called
secretion”.
used,
from
the
We
and
secretion,
“uptake
may
whole
or
probably
is
from
on
the
secretion”;
observe
process
the medium
so
depending
that if the
meant
that
the tissue,
to
466
the vessels.
for
The
brevity’s
secretion
is
secretion
to
water
It
INTO
indicates how
a
plants did
to
case
an
roots
increase
A
(fig. 6).
on
a
osmotic
salt
cretion,
of
both
of
but
in
the
secretion
on
a
6.
Increase
in
the
that salt
to
for
can
This
the vessels.
(Broyer,
conditions.
condition of the
the
The
reduction
a
of
of
is
day,
a
This
is.
roots
both
salt
previous
of
in
night
avoid
to
a
solution
the
caused
by
a
(a
exudation
the
caused
by
outer solution.
a
6
solution
in
and
were
and
of
the
the salt
of mannitol
salt
greater
for
se-
than
stronger salt solution
again removed from the medium,
to
the
accu-
having been
changes
exudation
both
by
experiment
of exudation
rate
of
condition
shown
water
when
expected
solution after
equilibrium
was
be
their salt
This
Substitution
were
rate
salt
possible.
not
in such
water
weak salt
during
before. A considerable increase
Fig.
and
exudation
weak
a
should
improve
to
condition
(2 H). When the salts
is
from the tissue
distilled
on
medium).
caused
plant
section
uptake
guttation
instead of distilled
increased.
solution
the
preceding
have
medium.
put
the
part of the
considerably reduced. It seems reasondepletion of salts in the root cells. In that
mannitol
used
value
secretion
the
was
to
show
salt
the
was
cases
the “tissue
expressions
were
the
the
from
plant
solution
mannitol
of
to
opportunity
the
salts
mulating
this
of
exudation the salt
been
exudation
attribute
have
had
the
when salt
transported
not
important for
plant
and
secretion
condition
even
known
are
it from
in both
is
exudation
extra
that these
salt
it
uptake,
VESSELS
that salt is
plants
1951). Barley
When
used
medium.
salt
THE
the vessels
to
the fact
salt
the
demonstrated in
been
to
Low
able
from
between
points
but is
When the
salt
the
distinguish
to
of the transport of water;
SECRETION
off
the exudation:
in
understood, however,
Relation
has
water.
favourable for
“uptake exudation”
comes
of
transport
some
increase
an
cause
least
given
altogether correct,
not
conditions
It should be
the
at
§ 2.
by
called
exudation”.
refer
be
may
causes
in
increased
accompanied
could be
expression
VAN ANDEL
sake.
The tissue
be
M.
O.
temporary
neither
addition
of salt
INFLUENCE
THE
did salt secretion
secretion
80
condition of the
salts
could
in
this
roots
taken
be
OF TOMATO
from
experiment
this
it
from
0.31
be
can
medium,
the
salts
the vessels
to
secretion.
In
inhibited
for
this
a
plants remained
that
salt
the
plant
the
of
as
result
be
to
of
solution without salts
of
of the
the
16
(about
composition
In
the
The
the
tissue
had
been
experiments
hour
only,
altered
medium
of
transport
for
an
been
from
up
secretion.
most
half
for
have
of
taken
tissue
hours).
will
roots
be
direct
a
uptake of salts
on
a
by
salt
that the
importance
the
however,
time
condition
as
that is
0.56,
to
can
of
increased
an
appears
experiment
value
medium.
long
Influence
§ 3.
well
as
of the
pretreatment
be
apparently
can
same
concluded
The increase of the salt secretion when salts
the
the
to
467
PLANTS
improved during the periods when
have
must
up
EXUDATION
decrease could be observed. The salt
some
From
%.
THE
of exudation decrease
course
increased
approximately
SALTS ON
rate
nor
of
before, although
OF
on
so
less.
the
exu-
dation
Relation between
a.
The
the
of exudation
rate
proved
be
to
stimulated
salts in the medium. It may be asked which salts
Only
can
data
meagre
be
the
on
influence of
found in literature.
taining
mixture
a
of
In
sometimes
salts;
KHC0
with
of wheat
that of
3
found
in
plants
plants
decrease of the
a
this
that
the other salts
did
not
Raleigh
(1946)
Nitrogen,
phosphorus,
by
adding
medium.
solutions
nitrate,
Addition of calcium
however,
lacking
one
but
plants
of
used
were
which
presence
guttation.
on
could
deficient
be
potassium
had
been
deficiency
evoked
the
to
In
effect.
no
of
the exudation.
salts
magnesium had
or
(1945)
concluded
potassium
or
and
4
increase
an
He
The
on
guttation
other element till
or
2
cases.
and
phosphate
con-
effect
KH P0
a,
Lundegardh
two
calcium
guttation,
no
osmotic
reckoning. Comparing
the exudation.
influence
the
magnesium,
used
were
of KNO
have much influence
investigated
respectively
experiments
the first
impede
seem to
showed
plants
tomato
in
of
the exudation
on
different
of the
out
presence
concerned here.
of exudation with however
rate
nitrate would
the
distilled water,
on
by the
solutions
solutions
on
the concentration of the sap
from
cases
of exudation
rate
are
various ions
several
of different salt solutions has been left
the exudation
the
composition of the medium and
these
grown
symptoms
in
were
evident.
To
gain
exudation
replaced
by
first
case
rate
way
as
has
impression
an
solution
a
of
the
when
studied
was
lacking
of exudation and
been
shown
in
fig.
a
of various
importance
complete
nitrate, phosphate
In
sulfate.
the other
cases
no
the
was
In
decreased in the
salt secretion
1.
or
anions
solution
Hoagland
the
same
change
was
observed.
These results
salt
secretion.
which
gated.
indicate
that nitrates
This conclusion
can
in
be
particular
confirmed
the influence of different solutions of
The concentration of the salts
was
can
single
the
stimulate
the
by experiments
same
salts
was
every
in
investi-
time.
The
468
O.
solutions had
Changing
caused
attained
phate
or
bonate
7.
made
isotonic
the
of
whether
to
Changes
of
rate
a
the
no
in the rate
7).
This
mannitol and
means,
Conversely
be
that
an
in
after
instead
of
happened
8.
a
a
having
potassium
of exudation resulting
Increase
in
of the
value
these
plant
were
cases
the
was
been
on
nitrate
8,
rate
of
P0
2
the
4
same
was
level
mannitol,
phos-
and
bicar-
phosphate
exudation,
from
exudation
KH
at
changes in
least in brief
the
composition
medium.
nitrate solution
phosphate
(experiment
the
on
the
immediate increase
observed when
nitrate
Fig.
of
or
contained
presence
necessary.
of mannitol
of
rate
equilibrium
solution
The
if
solution
The
exudation.
influence
The osmotic
mannitol
a
s
outer
(fig.
have
medium consisted
when
adding
solution of KHCO
of the
experiments.
by
of the KN0 3 solution. At
bicarbonate
seems
VAN ANDEL
solution of KN0 3 for
decreased when
instead
given
was
been
0.005 M
decrease
a
likewise
was
Fig.
a
M.
present
salt
in
fig. 8).
a
the
M
solution.
outer
was
the
0.042
decreased.
of exudation could
was
chloride
by
when
and
solution of
phosphate
caused
the medium.
M
solution of
Potassium
of exudation
in
rate
to
isotonic
potassium
0.046 M
secretion
the
transferred
an
was
sap
but 0.040
potassium
mannitol.
used
could
adding KNO3
If
nothing
cause
or
KCl
an
to
THE
increase
for
in
rate
same
for
or
caused
such
to
in
was
a
in the medium. A
present
the presence of nitrate
only by
We
must
From
investigate
now
the data
calcium
general
would
K
experiments of several
different
conditions
such
phenomena
the
tated
In
supply.
differences of
plants of Phaseolus,
when the
than
outer
solutions
well
as
these
the
reverse
found
(1939)
a
little
containing
intact
much
that the
of the
cells would
root
uptake of water,
(1943,
1945)
assium
was
differences,
however,
and
not
so
which
water,
expect that
much the
In table 4 values of the
which
were
are
be
obtained when the
much the
resulting from
same.
gradual decrease
however,
in
the
as
as
It is
potassium.
not
as
or
attributed
thing could be
In
most
for
this
seen
cause
the
It
effect
only promotes the
well.
and
the
seems
of
calcium would
in
the
during
an
the
potThe
has been
perhaps
of the
roots
factor k.
given,
are
solutions of pot-
on
change in the
result
of any
hour. These
an
rate
found,
of exudation
so
a
long
as
on
This
change
experiment.
salt
the
longer period
particular
the whole
unbalanced
complete
a
Lundegardh
permeability
sodium nitrate for half
experiments
although
salt
on
use
in
experiments
reason,
The chlorides
same
the
to
swelling
known from
favourable effect.
had been
plants
the
the medium since it continued
supposed
of exudation could be observed.
rate
in
with
of exudation if
rate
a
changes
No sudden
not
was
grown
than
He
deficiency.
nitrate concentration remains unaltered. Sometimes after
decrease,
water
calcium
small.
change of the medium
a
plants
calcium
of exudation and salt secretion
rate
(1934)
decapi-
more
the result of the
as
had
potassium
appear
assium, calcium, ammonium,
values
secondary
and little
with
transpiration
salt secretion
should
under
importance
took up
much
Ca
water
calcium
to
seem
hampers
shorter time:
ones,
retardation of the
a
be of
can
a
plants that potassium
whereas
present
We should thus
affect
less
but diminishes the
also found
and
stated
grown
experiments
exudation
potassium
give off
with intact
experiments
been
case.
stronger
under the influence of
protoplasm
were
potassium
cultivated in conditions of relative
plants
has
However Tagawa
1934).
as
importance.
have been obtained from
development
solution contained
in
did
they
Speidel
to
effect
potassium
while Ca
water,
however,
1927; Gaszner and Goeze,
(Kisser,
of
uptake
of
are
It
days, during which plants
of salt
as
expect
also demonstrated the influence of K and Ca in
be
salt
chloride in the
or
that
influence.
some
of these results,
cations
extent
should
we
have
promotes
Most
process.
what
to
uptake
water
on
especially
that in
a
the nitrate.
as
of
solution.
outer
for
extent
an
solution
469
PLANTS
potassium chloride
night, the exudation did not attain the
whole
a
OF TOMATO
EXUDATION
not
been
when nitrate
as
be
to
seems
had
roots
THE
ON
but
exudation,
the
hours
some
this
the
when
Even
SALTS
INFLUENCE OF
solution.
It
of
might
The
same
the influence of various anions.
Hoagland
presence
solution
of nitrate
has
been
appeared
used
sufficient
effect.
of various
the
elements
exudation
that the salt
(table
secretion is
not
were
also
proved
to
have
the
4).
much influenced
by the
nature
470
O.
of the cations
potassium
salt
Indeed
k
value of the sap
replaced by
was
ammonium,
or
in the medium. As neither the
present
the osmotic
nor
we
solution of
a
remain
to
of
and
exudation
salt secretion
in
would
Expe-
Medium
kno
NaN0
9.
.
b
.
3
10.6
0.46
kno
Medium
b
..
0.42
nh
conditions.
different
containing
were
no
4
isotonic.
kno
3
Ca(N03 ) 2
3
9.8
8.6
8.4
8.6
0.39
0.33
0.33
0.33
.
.
0.75
15.0
0.73
kno
b
.
14.6
S
.
kno
10.6
12.0
0.52
0.48
0.40
KC1
NH
when
containing
7.8
8.0
pened
when this solution
nitrate
potassium
there
is
the
such
over
long
Concentration
composition
Different
that
the
replaced by
was
the
the
(1925)
In
in the sap
outer
and
of the
composition
exist
opinions
concerning
concentration of ions
while
k
in
n
(1934)
(potassium,
to
a
large
constants.
so
the
to
that
in
the
this
salt
case
Thus he
ammonium
and
(1943,
that in
1945)
as
increased,
only slightly
enhanced.
The
amount
of salt
rate
outer
kc
sap
x,n
,
the
s
medium
outer
potassium
the
=
found
in the
concentration of the
the
in
s
lower
concen-
that
an
solution
well
solution contained calcium
was
was
in
that the
medium:
c
found potthan in the
magnesium)
potassium nitrate
sap
of their
found
were
the
con-
Sabinin
of every ion present
that ion.
calcium
the
to
independent
the contrary stated
outer
of the medium
between
According
is
sap
increase in the concentration of
decreased because
greater
however,
relation
higher concentrations
Lundegârdh
concentration of the
concentration
in
sap
amount
their concentration in
nitrate in the sap. When the
the salt
the
for
and
on
increase in the concentration of
caused
hap-
of calcium
one
change spontaneously
the relation
concentration of the ion in the sap,
and
solution
a
nothing
experiments,
can
exudation
The
the sap in
calcium
Laine
proportional
in
solution.
characteristic
phosphate
trations of cations
and
outer
should be
solution,
the
on
of the medium
concentrations.
being
hours
nitrate,
opposite
similar
exudation
7.4
period.
concentration in the
assium and
0.44
KC1
7.2
four
calcium
or
centration of the sap and that of the medium.
was
0.46
7.0
twenty
nitrate
respectively.
difficulty
a
for
plant had been
a
only potassium
3
4
.
Even
4
11.8
NaCl
C1
no
nh
3
12.4
CaCI,
8.4
KC1
3
12.2
0.48
0.57
kno
3
KC1
b
.
0.60
NaN0
11.4
Medium
b.
Ca(N03 ) 2
3
16.4
3
or
solutions
salt and
kno
Ca(N0 3 ) 2
3
16.6
Medium
9c
these
.
S
9b
on
3
10.6
much either.
change
not
a
calcium, sodium
.
S
9a
M
kno
3
solution of
a
4
equilibrium
cations. The solutions contained 0.005
riment
salt of
a
of exudation
rate
when
unaltered under
TABLE
Rate
changed
were
deduce that k
can
proved
was
VAN ANDEL
M.
as
of
nitrate
when the
of exudation
solution
given off
to
the
was
sap
INFLUENCE
THE
did
alter.
not
salt
more
influence
On
could
necessary
between
salt
also
different
osmotic
Even if
depends
of salts
k,
pointed
the
factor
in
of
means
again
secretion
of
representing
of
the
will
depend
centration
that
taking
on
of
the
per
sap
unit
table 5
one
up
some
of salts
amount
the
in
It
of
salt
one
uptake
but
the
will be
which
must
the
clear that
salt
that the
so
salt
outer
many
possibility
concentration and
Lundegardh
as
the
varied.
Finally
turn.
only
for
that
(1945)
has
secretion
from the medium. As
this
this
changes
be
part
of
not
concerns
in the
in
the
found
the
depends
the
process
medium, it might
between
salt
of salt
the
con-
secretion.
in the
changes
amount
the
on
latter
given
For
concen-
off
the
to
of time.
point.
from
are
The
to
part
the
be
case
could
medium
any
no
is
some
calculated
salt
regularity
can
experiments
secretion
is
by
to
of the
be attributed
to
salt
on
subtracting
in
the
be observed
increase
done
depending
available
the addition of salt
with the
Irregularities
of
seen
of the salt
given off when
secretion
the medium.
is
relation would
from the salt secretion after
Only
transport,
its
of the salt
part
salts
condition of
not
altered,
was
influ-
expected.
medium and
the results
determine this
uptake
water
its
formula
be
to
salt
was
is
has been
unit of time also
the concentration of the salts
that
tration of the
In
the
as
the salt concentration of the
between
simple
mentioned above,
reasons
of
rate
only by
relation
a
hardly
seen
of
expected
vessels
by
stated,
We have
be
the
medium
possibility
the
on
the sap
per
some
of the sap
things, influenced by
secretion
vessels
no
of water and the transfer
depends
salt
the
of
solutions
The transfer of salts
plant.
the
be
to
results.
of different
transport
by its osmotic value.
also
In
small.
the concentration
concentration in
not
sap.
were
considers
however,
these
effect
also
the
to
in
been
is
it
relation
that of the
concentration
influence the concentration of the sap,
can
already
when
salt
is influenced
solution but
factors
the
the
concentrations
have
may
concentration of
off
section 1,
concentration of the medium,
but it
1,
the
change
influence
their
the sap
evaluate
to
in the salt
given
a
medium and
Lundegardh,
on
with each
change
sap
some
value of the medium
The first is, among other
section
to
con-
although
sap,
investigating
but
argued before,
we
Moreover
found
amount
This
As
that differs
out
in the
demonstrated in
effect
the relation between the
roots.
Lunde-
solutions of different concentrations had
difficult
by changes
enced
osmotic
values;
the vessels.
factor
a
their
medium
arise.
on
to
that
when
eliminate the osmotic
we
difficulties
been
isotonic
not
were
of the
is
actually
definite relation between the
solutions
experiments
It
importance.
471
PLANTS
nitrate
potassium
of the osmotic
has
osmotic
effect
TOMATO
concentration increased.
concentration of the
that
so
Lundegardh’s
influence
which
isotonic
solutions
low,
contained
the salt
as
OF
demonstrated.
sap,
use
the
Laine’s
rather
be
of the
of the
to
solution
EXUDATION
salt in the medium and
a
account
that
on
THE
ON
therefore find any
not
centration of
the
SALTS
given off
was
did
gardh
If
OF
the
outer
to
the
the
medium,
solution.
in the increase of
concentration of
several
factors.
The
472
O.
the
important is
most
tissue secretion
VAN
the
during
referred
are
ANDEL
of salt secretion.
periodicity
changes
readers
nomenon
M.
to
For
day.
section
7.
It
appears that the
discussion
a
If
found
uptake secretion by subtracting the tissue secretion
the
time from the whole
of salt
amount
given off
TABLE
Relation
between
the salt
concentration
phe-
at
one
another time, incorrect
5
of the outer solution
isotonic
(on
at
of this
therefore calculate
we
and
the salt
secretion
solutions)
Salt secretion
3
in
M/30
X
mm
sec.
Medium
Hoagland
100
%
1.26
1.04
1.01
0
%
0.65
0.90
0.61
10
%
0.90
20
%
1.04
30
%
50
%
200
%
100
%
„
„
„
„
is
half
be
can
the
amount
The
in
of
salt
medium
impossible
salt
leads
the
to
mainly
in
P0
Cl,
S0
4,
NH
plants.
Large
do
trees
not
and
4
4,
to
mentions
the
organic
and
Much
nitrogen
nitrate
of
The
were
the
plant
some
We
amino
as
be
on
a
in
the
amounts
the exudation
sap
sap
of
amounts.
of various
only,
of
organic
acids
of
of
plants.
and
was
on
pumpkins.
tomato
while the
chloride,
that had been
Broyer
Laine)
demonstrated. Chloride
plants
1945)
plants.
to
bicarbonate,
or
ions
herbaceous
1942; Skoog,
(according
large
of
in the exudation sap
solution
as
and
compose
(1943,
small
very
appear
carbonate,
the sap of
well
potassium
did
a
very
found
only
other
distilled
ions
water
not
calcium
as
probably
succeed
in
ammonium seemed
and
always
to
be
predominating.
the
demonstrating
presence
of sugars
or
acids.
Approximately
chezia
found in
at
time.
Potassium
present,
was
found in
also
as
nitrate
of wheat
sap
in
present
relatively
phosphate,
also
the
been found in the sap
compounds
was
presence
little
sulfate could
when
of
presence
of
Lundegardh
sap.
Litvinov
1938).
medium
should
they
(Van Overbeek,
occur
Grossenbacher,
and
the
presence
that
nitrate in
were
conclusions
the
of
for
concentrations
vessels.
of sugar such
amounts
seem
Ca
have seldom
Organic substances
few
so
draw any
to
supposition
potassium
solution
certain
concentration
the
to
a
of
the exudation of the
important part of the ions
found indeed
for
is
on
influence
the
off
given
for
importance
the
an
that it
be
shall
plants
between the
relation
—
0.72
—
obtain reliable osmotic values for the sap
that
so
investigated
the
to
hour,
an
0.77
1.22
1.35
necessary
least
0.58
1.08
—
the
0.83
—
1.16
that
0.66
—
1.01
—
will be obtained. To
values
it
lb
la
experiment 2
nobilis,
chloride;
the
but
that is
to
same
the
say
sap
results
of
were
this
that chloride
found
plant
could
with
seemed
also
be
to
plants
of San-
contain
more
demonstrated in
INFLUENCE
THE
the sap of
with
tap
The
results
ferent
which
of
Sap
The
roots
collected
was
of sap
amount
of
a
be
to
of the osmotic
were
it
tration
that
appears
other
small
too
of
not
are
solution.
nitrate
The
cretion of
coincided.
the
nitrate
of
chiefly
dif-
solutions with
It is
nitrate
have
only
From
importance.
and its
con-
not, how-
concen-
been
present
that the various cations
the
nitrate
the
given off
was
decreased. Next
in
again
morning
The
phosphate.
proportionately
but
secretion,
the
changes
found that under
we
to
amounts.
greater
than
changed
solution of
a
in
always exceeded that of
nitrate
vessels
Like Lundegardh
consists
sap
off
more
into the
the
sap
likewise
given
much
than
day
much
could
evening less
were
sap
phosphate
the
during
and
contained
sap
salt
(the
and
the exudation.
while the exudation of sap
vessels
both
the
By
day
later)
of
These
determine the
to
found earlier
The nitrate concentration of the
Hoagland
the
phosphate.
of
were
anions
for
importance
great
ions
we
of
isotonic
on
value of the sap
in very small amounts, while
concentrations
during periods of approximately
was
that other
expected
comparison
the
times
centration of other ions beside nitrate and
ever,
chloride.
will be shown
as
solution made
Hoagland
a
473
PLANTS
summarized in table 6.
are
day
OF TOMATO
some
different
at
the
that the
so
on
always
the sap
during
circumstances
hours.
two
EXUDATION
determinations
in
made
were
changes
without salts.
or
THE
contains
several
phosphate
determinations
secretion
SALTS ON
that had been grown
plants
water,
nitrate and
OF
nitrate,
se-
more
usually
these conditions
probably
potassium
nitrate.
When
isotonic
plant
a
solution
given off
was
of
stituent
distilled
If
more
also
nitrate
of
quantity
and
exuded
to
less
had
plants
hours
be
the
off
been
on
one
con-
up from
the
mannitol solution
a
given off
third of the
to
the
quantity
solution.
by
replaced
a
and
the vessels
to
on
Hoagland
a
was
taken
of nitrate
amount
approximately
was
salts
could be
salt
no
an
nitrate
Nitrate however remained the main
by changes
while
water
for
2-4
taken up
as
secretion of
phosphate
the
plants
hours,
(table
phosphate
diminished
phosphate
than
6).
Hoagland
solution
the exudation of sap
were
on
during periods
This could
lead
into the vessels
Also when the
four
sap
of
even
uptake
phosphate
a
plant
to
in
which
hours after
did
rate
not
outer
not
was
distilled
or
could
of exudation
being
Conversely
the
always increase when
as
on
the
was
inhibited for
much
which had been
decapitation
phosphate
phosphate
solution
was
so
influenced
considerable increase in
a
the
of salt
was
be
to
more
mannitol solution
a
could be taken up from the
The
appeared
sap
of the smaller nitrate secretion.
result
time the secretion of
twenty
the
Sometimes
concentration of the sap,
a
phosphate
with nitrate.
nitrate.
in
of the medium.
off
the
given
was
given
be
plant
without
sap
solution
Hoagland
a
was
increased.
The
less
the
while
solution
a
for 36
might still
from
less
when
decapitated
water
vessels per hour
secreted
even
sap
medium. When
or
mannitol
the vessels.
to
the
transferred
was
of
affected
distilled
a
as
that of
water
contained about three
case
longer
for
quarters
474
O. M.
VAN
ANDEL
of
amount phosphate m.e /hour 0.0 26 0.0 4 0.0 46 0.0 46 0.0 49 0.0 23 0.0 26 0.0 024 0.0 17 0.0 026
j
I
|
|
j
0.0 16 0.0 16 0.0 16 0.0 17 0.0 1 0.0 08 0.0 1 0.0 12 0.0 14 0.0 17 0.0 15
,
1
j
M M M M
M M
M M
M M
M M
M M
M M
M M
M M M
M M M M
M M
M M
M M
M M
M
concen- tration phosphate 0.0 10 0.0 16 0.0 16 0.0 17 0.0 18 0.0 12 0.0 1 0.0 18 0.0 15 0.0 12
0.0 04 0.0 04 0.0 04 0.0 04 0.0 03 0.0 02 0.0 03 0.0 02 0.0 07 0.0 09 0.0 04
of
5
s
Hoagland
a
of
on
amount nitrate m.e /hour
days
0.061 0.063 0.062 0.059 0.051 0.030 0.042 0.024 0.017 0.036
0.068 0.072 0.071 0.060 0.057 0.057 0.061 0.063 0.023 0.020 0.056
M M M M
M M MM MMM
M M M M M M M M M M M
two
during
off
given
6
lacking
nitrate
of
concen- tration nitrate
plant
an
or
sap
s
s
5
5
14
0.024 0.023 0.022 0.022 0.019 0.015 0.017 0.018 0.0.0014 0.017
j
M
M M
M M
M M
M M
M M M
M M
M M
M M
M
sap
0.049 0.051 0.050 0.047 0.045 0.034 0.034 0.034 0.035 0.033
nobil s
Sanchezia
0.018 0.018 0.018 0.015 0.014 0.014 0.015 0.016 0.012 0.011 0.013
M M
M M M M
M M
M M
M M
M M
MM M
0.033 0.034 0.033 0.032 0.032 0.025 0.030 0.031 0.027 0.021 0.027
10.
10a.
Experiment sap/hour
2.539 2.722 2.810 2.666 2.682 1.945 2.449 1.331 1.14343 2.045
Experiment
3.888 3.992 4.010 3.990 4.036 4.200 4.058 3.934 2.005 1.843 3.540
g.
g.
solution
amounts
and
6
5
|
solution Tomato osmotic value
TABLE phosphate isotonic
and
of
of
salt
!
medium
of
Hoagland HoaglandHoagland HoaglandHoaglandHoaglandHoagland Man itol Man itol Hoagland
Quantiy
|
1
|
j
|
|
j
I
I
8.15
time
Hoagland HoaglandHoagland HoaglandHoagland HoaglandHoagland HoaglandMan itol Man itol Hoagland
8.15-0.15 10.5-12.5 12.5-14.5 14.5-16.5 16.5-18.5 8.15-0.15 10. 5-12. 5 12.5-14.5 14.5-16.5
8.15- 10.15- 12.15- 14.15- 16.15- 18.15- 8.15- 10.15- 12.15- 14.15-
8.15
8.15-0.15 10.5-12.5 12.5-14.5 14.5-16.5 16. 5-18. 5 8.15- 0.15 10. 5-12. 5 12.5-14.5 14.5-16.5 16. 5-18. 5
8.15- 10.15- 12.15- 14.15- 16.15- 18.15- 8.15- 10.15- 12.15- 14.15- 16.15-
THE
the
of
amount
These data
10)
well
as
Fig.
the
on
used.
were
solutions
Fig.
9.
small
A
isotonic
in
increase
in
salts
replaced
is
The
fig.
large
again
suggests
which
from
the
is
seen
up
the
can
that chloride
mean
outer
of Van
to
a
KH
experiments
the first
to
and
P
2
the
three
potassium
most
of
clearly
was
when
a
solution
the
directly
seems
from the tissue
is
greater
part
transported
(unpublished)
are
of
lacking
chloride.
potassium chloride
appears
the vessels
to
however,
to
quantities
the chloride
directly
to
that
the vessels.
is present in the tissue in small
that
accompanied
already been demon-
remarkable. It
transported
nitrates.
medium, chloride
This
of chloride when
goes
considerably
lacking
increase of both.
an
potassium
mannitol.
decreased
has
as
phosphate given
or
O4
solution
quantity.
from the medium. It
solution
Nie
these
chloride from the
medium is
be
quantity of chloride
the
up
KCl,
caused
medium
solution
from
nitrate,
10a).
solution of mannitol
added
of nitrate
transferred
decrease in secretion
would
results
a
a
chloride
nitrate,
sap,
in considerable
This
by
having been taken
small
was
the exudation of sap
removed
like
chloride,
8.
of
secretion
were
to
In
or
third.
experiment
uptake of salts
injurious effect from
containing KN O3 ,
and
found in the sap
an
KC1
6,
one
6, experiment
of the
vessels.
Hoagland
a
to
(table
(table
4,
4
on-
isotonic.
could take
plants
the
off
475
PLANTS
decreased
influence
P0
eventual
an
TOMATO
plants
nobilis
2
of the amounts
plants
strated
a
KH
solutions
of sap
time the
When the
was
into
KN0
were
Addition of nitrate
by
nitrate
OF
given
was
tomato
quantity of CaS0
solutions
Exudation
was
of
3,
Comparison
off on
every
of
0.005 M
to counteract
The
ions.
the sap
been
nitrate
demonstrates the great
secretion
solutions of
of
of Sanchezia
that
EXUDATION
THE
that had
quantity
for
are
as
also
9
SALTS ON
phosphate
while the
solution,
OF
INFLUENCE
the
in favour of this
that
after
only
This
only,
taken
vessels.
up
The
supposition.
476
O. M.
The
of chloride
amount
on
distilled
of
potassium
increase
for
water
chloride had
and
days
and
the first
few
been
in the
present
some
chloride
after
VAN ANDEL
transported
and
to
increase of the tissue secretion and
have
been
expected
similar
case
arises
assium
nitrate;
the
before this
course
compare
In
by
the
phosphate
more
phosphate
while
phosphate
time
long
solution
of
concentration
the
transfers
so
have
main
the
This
was
indicate
long
to
with
be present
from
the
permeate
into
to
the
that
tol into the vessels.
ing
in
a
its
In
rise
few
of
that
rather
a
phosphate
chloride.
or
could
phosphate
replaced
was
as
the vessels in
not
by
the
of
The
secretion
is
from
when
the
will
that
concentration,
no
salt
of
potassium nitrate),
remain
the
the
tissue.
osmotic
nitrate remains
of the
the
off
secretion
then
in
uptake
conductivity
given
tissue
available
comparison
a
phosphate
phosphate
so-called
other
some
the
takes
place.
(nitrate
sap
conclusion
same
increase
in the
rate
It
has
supposition
been
pointed
appears
really is
no
the
of exudation after
(1943) supposed mannitol
to
be
out
evidence for the
already
superfluous.
The increase in the osmotic value of the
by
in
the
From
must
we
permeation
in the osmotic value of the medium is caused
salt
a
take
can
the determinations of the salt concentration of the sap
conclude that there
period,
next
indicates
influence of
the medium Eaton
roots.
this
it
phosphate
solution for
results.
explain the gradual
addition of mannitol
This
transport
that
to
phosphate
by determining
to
Introduction
The
amount
only
vessels.
nitrate
being
to
the
the
on
the sap
checked
experiment,
phosphate
a
mannitol solution
that
its
sap
another
medium.
the
The small
concluded,
already
reached
of
next
8).
sufficient
as
being supposed
To
(fig.
chloride.
may
again
In
In the
from the medium,
the secretion of
found;
vessels.
a
time.
same
hours.
two
absent
with the fact
constituent of
value of the
during
was
phosphate is transported
phosphate
unaltered
We
the
of the medium
vessels
the
much slower than that of nitrate
consistent
nitrate and
to
be
phosphate
that
seems
it would be
necessary
at
from the medium,
up
the exudation when
stimulate
It
from
the
four hours. Of
further increase followed in the
reaches
to
seems
conclusion is
way
a
pot-
and
to the
phosphate given
potassium nitrate was replaced
substitution
absent
taken
is
before it
the vessels
This
but
was
A
off
the vessels.
to
6).
solution of
a
of
an
might
(fig.
6
of
amount
has been
same
secretion
twenty
certainty
phosphate
given off
was
tissue
the vessels
to
chloride
solution of
potassium
nitrate solution,
to
a
time increased after the
when
a
9)
recorded here, the
this
to
(fig.
when
than
more
of
however when the phosphate
period
a
11
solution of
a
not
secretion
on
further
amount
the
experiment
given off
could be stated with
change
not
for
uptake and
experiment
did
sap
increase
to
in
solution
a
any
considerable
a
plant is put
of nitrate
amount
on
accumulated in
seen
low salt
a
put
show
not
of the whole salt
so
have
we
when
exudation continue
to
as
When
which had been
plants
did
decapitated,
hours.
of
sap
had then been
now
of manni-
sap
an
follow-
increase
concentration.
cases,
however,
the osmotic
value of the sap did
not
con-
INFLUENCE
THE
form
nitrate
the
to
which could
sap,
than
that
nitrate and
culate
is
pointed
osmotic
the
as
present
of
high
too
calcium
the
from
time
on
distilled
the
medium
a
total
were
by experimental
from
the
of
amount
If
high.
too
the
value if in
when the
salts
lacking
cal-
we
of
amount
fact
nitrate
of the nitrate
some
(0.01
could
M
than
boric
be
to
was
expected
had been for
plant
solution of
(a
difference
value
osmotic
higher
differences
salt.
especially
The
water).
for
of the
was
fully dissociated potassium
as
Several times the sap contained less nitrate
from its osmotic value,
value
content,
the
found,
somewhat
sap
a
osmotic
nitrate
477
PLANTS
chapter Material and methods
exist
to
TOMATO
calculated
sap
the
OF
accounted
may be
nitrate
shall obtain
we
the
value
all
supposing
be
in the
out
of
When
been
actually
phosphate found
the
EXUDATION
from its
they might
concentration
the
present,
nitrate,
calculated
that
so
THE
concentration.
be
It has been
errors.
SALTS ON
that had
the value
always small,
OF
mannitol
amount
to
well
usually
was
as
fourth
one
acid), but it
longer
a
as
of
not
large.
so
This would indicate that other substances
of
presence
seem
than
be
to
concerned
be
to
was
We
As
phosphate could
have
or
proved
acid.
as
wheat
but bicarbonate
Under
certain
sating
in this
of
bicarbonate
case.
We have tried
substance
The
rise
after
6.8
The
to
titration
was
10.5-11
and
one
curves
9 and
10. In all
Were
capacity
organic
good buffering
by making
of malic
a
acid
at
sap
was,
pH
titration
to
found
to
of
sap
shift
a
of
the
from
resulting
a
compen-
by determinations
supposition
of the unknown
nature
of the sap.
made in
the
5.5
pH
and
6.0.
It
could
the
following
are
proved
a
to
as
very
for
after
the
case
by
seen
half
was
in
ml
a
small
between
expected.
addition
the sap
sap
unit.
was
of
a
10,
and
The
6 and
7
ranges.
pH 3.5 and
acid,
This
of
first
fig.
found in those
instance malic
values would be
In this
it
be
pH of the
largest between pH
be
maximum
however,
such
shift
to
to
15
way:
pH having been adjusted
The results
necessary
curve
the sap.
the
the sap.
between
HC1,
curves
acids,
low
found in
the relation between the
dilute acid
in
present
According
days.
NaOH.
of the
pH
this
curves
was
were
represented
of
he
impression of the
two
or
capacity
The buffer
5.5.
an
titration
by adding
amount
buffer
gain
be
anions
concentration of
titrated with diluted
in which is
the
to
and
He confirmed
making
not
opinion bicarbonate would be
pH of the sap itself
to
sap
by
are
most
bicarbon-
demonstrated in considerable
circumstances
(K+)
In his
shortage of the latter.
seemed
carbonate,
acids
can
be
can
greater
substances.
or
it
present,
amino
acids
organic
no
relation between cations
the
be
to
has been mentioned before.
(1945)
plants,
and
Sugar
quantities
Lundegardh
quantities.
this substance
identifying
were
Electrolytes
also
was
sap
concentration.
nitrate
the unknown substance would be
organic
an
demonstrable
of the
conductivity
the
also be present. The
can
for the difference.
account
from
expected
compounds
plausible that
ate,
the
as
succeeded in
not
carbon
not
present
was
small
a
verified
quantity
actually much
more
478
buffered
The
buffering
of
This solution
unit
much
of
Relation
and
phosphate
than
the
The
(1949)
and
solution of
is
to
the
at
the
always
in
have
very
can
accordance.
been
The
at
well
it
to
small
a
shift
of KH
and
the
4
M.
0,001
this
7,
stronger in
that
the
solution,
a
fact
amount
and
small,
.
O3
to
very
as
KHC
6
and
half
pH by
O containing
P
2
amount
added
seems
be
buffered, which
When
phosphate
pH
So
of the
(3)
pH
of
probably
concen-
The
This
may
and
to
and
according
(9)
that
be
the
of these
higher
at
values
a
to
changes
partly
that
The
not
(Von
too
to
sap
are
However
experiments
1952).
maximal
less
There
roots.
by
the fact
to
Lundegardh
permeability
attributed
partly
to
medium;
values.
pH
much
very
(Drawert,
be
the
uptake by
water
results
the exudation
pH of
high
or
on
on
not
influenced
used
found
lower
is
experiments
be
investigated
usually
decrease
low
solution.
outer
was
Meinl,
so
titration
concentration
same
required
solution
roots
changes
to
between the methods
ability
not
presence
a
difference between nitrate
outer
wheat
many
of tissue
the
for
influence of
known from
pH of
jects
the
was
must
sap
acids
value.
of
only
itself.
sap
the
account
sensitive
on
pieces
in
of the pH of the
very
M.)
the
by
of the sap
curve
of
of HCl
quantity
found between
the
by
exudation
few data
to
the
was
osmotic
exuded
was
be
to
proves
sap; � ─ �
present
sufficient
Influence
c.
it
as
shown
was
tration
of
between
buffering
bicarbonate
not
explained partially
solution
potassium bicarbonate (0.001
stronger
very
pH. • ------- • sap; � ─ � solution
the
that if such
fact
small.
the titration
phosphate
a
the
to
the presence of another substance.
to
10.
Fig.
of
be
be
can
next to
ANDEL
points
must
6-7
pH
fig. 10
ml
represented.
points
a
15
quantity
at
In
VAN
This
pH values.
their
phosphate.
curve
is
low
at
present,
are
of
M.
O.
water
in
the
not
are
differences
different obwater
acid
perme-
pH
Guttenberg
and
and
1952).
pH
between
of the
5.2
and
solutions used in the
6.0,
so
we
thought
preceding experiments
it
important
to
varied
investigate
to
THE
what
INFLUENCE
the
k,
the
paid
was
permeability
to
the
latter
the
vacuole is
The
H S0
2
at
the
the
solutions
fluence
exudation
by
the
6.5.
a
long
so
be
can
decrease of
mined
seen
More
passing
through
by
in
set
of KOH
several
changes
the
salt
acid
pH
value of the
no
of the
in
sap
value
had
equilibrium
and
decreasing
of
the
but
been attained,
the
so
osmotic
outflowing
vessels
the
salt
pH
of the
sap
of the
value
might
roots
secretion
saltsecretion
(()b);
determined
when
(S)
medium
and
the
Medium
Hoagland
solution
>>
on
had
the
sometimes
rate
was
influenced
of exudation
questioned
twice
to
small
a
if this
is
a
deter-
was
of exudation
probably rising.
was
The
have been lower than that
the
turn
time.
same
out
to
be
In
too
this
way
small.
7
of exudation
rate
conductivity
plants
at
would
TABLE
of the
Influence
be
may
not
the
decrease
a
13) indicate
(experiment
it
caused
by
rate
in-
drop below
the osmotic value of the sap
moment
pH of 5.2.
a
not
was
the
as
had
have little
to
solutions
increased,
sap
with
accompanied
was
level
when these
gradually
did
or
minutes
continuously
constant
no
alkaline
or
of the medium;
secretion,
the
decreased
hour
one
been
had
pH
addition
in table 7. The salt secretion
in the
osmotic value of the
for
stayed
water
on
pH
h
5.20
9.4
3.25
3.5
5.20
7.50
a
(b):
of the
certain
osmotic value
( k).
roots
solution
or
for
of the
All
values
one
hour.
S
k
0.043
0.40
170
0.091
0.32
66
9.1
0.047
0.43
166
8.5
0.050
0.43
170
«
)5
The
pH
the
the value
as
1945)
which
at
Hoagland solution
a
solution seemed
decrease. This decrease
real decrease. At
were
rate
whose
Hoagland solution
outer
its initial value. The data in table 7
sap
solution
exudation
after
even
of the
exudation
decreased the osmotic
the
Arisz,
to
either
of exudation increased
rate
pH
above
to
the
The
pH.
and
In
walls.
of exudation
rate
above.
the medium into
according
vessels,
3.4
to
replaced again by
the
on
of k. This
The
in
rise
or
the
rate
same
were
Changes
still
mentioned
decrease when
to
bear in mind that
goes from
the cell
similar
a
decreased
change of
been attained.
much
by
decrease in
tissue
con-
Special
identical with the
be
not
.
about the
4.5
proved
replaced
or
the
to
be
possibly
investigate the
we
479
PLANTS
of exudation.
we must
(transmeability
through
even
of
water
concerned,
are
TOMATO
rate
need
pieces
which
at
OF
medium could
of the
water,
the medium
or
7.2
to
The
4
after
of the
rate
roots
was
increased
for
roots
of exudation
rate
5.2)
EXUDATION
changes
determined
cytoplasm
(pH
of
water
from
goes
THE
ON
changes of k, although
to
the
case
while if intact
the
observed
conductivity
water
SALTS
changes in the pH of the
extent
cerned with
attention
OF
of
decrease in
the
k increased
When
present
It is
a
in
the
medium
rate
was
again, while
dilute acid
the
by
changes
reversible.
in
the
The value of
the osmotic value of the
or
medium,
probable that
of exudation caused
always completely
the
alkali
the
was
same
changes
used,
results
of the
showed a decrease.
sap
that is when no salts were
were
pH
found.
of the medium
are
of
no
480
O.
importance
in the
changes
another
value
§
the
to
the differences
as
4.
the
The
exudation
the
plants
out
already
of
of
that
an
more
in
increase
will
first
the
possibility
be
to
prove
off
given
the
on
the
applied
difficulties,
ceptible
the
of
the effect
as
after
only
medium.
twelve
found that
this
Using
roots
tomato
solution. It may
soil
which
meant
the
rather
exudation
instead
of
one
sucrose,
to
a
that
so
sucrose
still
14
of
increased
After
was
for
At
as
a
the
used: the
gradually.
after
method
this
find
with
way
experiments
solution
of
to
taken
it
the
outer
sucrose
have
in
our
own
grown
known from
was
the
by
up
solution,
used.
were
had
roots
of
however,
meet
this
Moreover
been added
was
containing manni-
isotonic solution
an
to
but
sucrose.
as
is
sucrose
per-
nutrient
a
value of the medium. To
of
is
sugar
(1950)
as
left
some
effect,
no
from
sucrose
up
available.
added
we
was
more
leaves
two
meets
in
could
was
rate
salt
opinion
sugar
reason
take
which
to
on
good
previously
Hoagland solution
isotonic
possible
effect
rate
the
was
gain
must
at
a
be
as
recorded
on
a
when
suddenly
considered
of exudation showed
the
on
a
while
added,
same
first
replaced
containing
idea of the changes due
time when
hour, approximately
been
was
solution
had been
was
the
the
some
plants
of exudation fell
minutes,
rate
with
sucrose
This effect
20
to
When the
time,
some
approximately
had
decrease in the
more
investigated
sucrose
made
effect.
first
have been attained,
while
this
a
first
The
11).
been
that it would be
present.
This
mentioned that it
(fig.
had
again
mannitol
to
with
was
solution
a
purely osmotic
solution
when
Went
low concentrations
on
a
sucrose.
Experiment
by
indeed
solution, whereas Went used plants
a
always compared with that
tol
able
increase in the osmotic
an
difficulty
In this
and
and Street and Lowe
(1938)
Addition
plants.
two
amount
the medium. Less
administered
technique
sprinkled
was
investigations just
tomato
found
to
be observed that in these
The influence of
the
if
pointed
the vessels.
to
sugar
have
can
probable
very
by submerging
sucrose.
sucrose
are
the medium consisted of
in
been
greater
a
Lundegardh’s
roots
plants
hours. For
the other hand White
on
the
to
solution of
a
in
because
vessels;
sugar
in
the stump
on
osmotic
increase
to
It has
or
given off
seem
glucose
nitrate would be assimilated in the
Went
shown
1944).
greater,
contrary
the addition of
on
to
not
the
influence of
of exudation
rate
be
must
of
follow
pH
unimportant.
(1945)
Lundegardh
of exudation
the
would
been
(Went
become
must
in
changes
alterations
that
moreover
solutions.
has
plants
sections,
preceding
appears
from
by
outer
sugar
osmotically active material
case
the
It
exudation under the
tomato
utilize
can
the
of
the
in
resulting
induced
changes
either the factor k
causes;
of
pH
content
Stimulation
described
rather small.
were
of exudation
to
salt
VAN ANDEL
phenomena
of
rate
course
or
M.
a
Hoagland
salts
same
purely osmotic.
should
gradual increase,
rate
Hoagland
of
and afterwards
equilibrium
a
were
solution
was
solution
attained
(whose
THE
INFLUENCE
osmotic value is
30
had
this
at
sec
stayed
When
amount
—
Fig.
Effect
of
as
adding
rule
sucrose
When
in
or
sugar
the osmotic
the
value
afterwards
mannitol
had
this
with
was
The osmotic
0.035
mannitol,
Although
active
case
proves
to
M
the difference
cause
in
the
0.038
the
general
be
must
after
was
small,
have been
in
a
on
by the
solution
of
to
of
the
presence
of
the rate
of
the
to
solution
amount
the
the
whether
same
that
solution
osmotically
and
lowered the sudden
a
greater
given off
strong
on
condition of
the
a
large
minutes.
be attributed
the
for
a
mannitol.
was
exudation. Thus
secretion
stimulated
of
indicates
cannot
stay
a
fifteen
Hoagland
medium consisted
stronger
the
a
about
effect
been used. This
value of the sap
when
substances
to
more
M
and
to
the
by
equilibrium had yet
no
approximately
was
exudation in the presence of sugar
of k.
takes
again
unusual
an
hour
one
mm/
plant
period.
suddenly
rose
27.2
to
changed
was
481
PLANTS
when the
sec
equal
an
of the medium
of exudation
rate
for
(0,02 M.)
exudation, compared
rise
OF TOMATO
mm/30
sucrose
but
—
a
13.4
of exudation
rate
effect
while
attained,
11.
the
osmotic
solution
containing
decrease followed. After
prolonged
been
EXUDATION
only
was
mannitol
a
solution
solution,
Hoagland
THE
lower). The rate of exudation amounted
time, while it
on
the
OF SALTS ON
stronger
a
of salt
with
of
change
equilibrium
and
sucrose.
osmotically
vessels in the latter
salt
secretion
active
sucrose
—
substances
in
or
—
the medium.
482
O.
We
of
at
first
as
the
because of the
decreased. This
Such
of
a
served.
given for
been
The
in
is
exudation
for
could
the
plant
effect
H
Sucrose
4-
of
plants
in
grown
sucrose
on
of
rate
daylight
lighted
(0.022 M.)
by
sugar
better
content
The
effect
It
taken
the
of
a
15
a
and
and
of
the
reduction
in
the
(fig.
could
roots
12).
of
more
salt secretion
S
11.5
0.43
11.30
10.3
0.44
12.00
9.2
0.35
12.30
9.1
0.35
13.00
10.8
0.40
13.30
12.5
0.50
14.00
13.0
0.47
cultivated in the
have been
rate
medium
When
to
As
in
of
the
or
the
salt
in
a
artificially
better
higher
for
the
of
this:
solution
the
a
gradual
rate
a
as
a
condition;
result
of the
after
20-30
in this
mannitol:
rate
as
of
first
sucrose
would
change
the
was
observed
osmotic
even
mannitol.
a
as
and
is
apparent
the
third
if
by
is the
value
and
sucrose
was
little smaller
The
a
now
replaced
was
medium. When
on
periodicity
tendency
we
period,
to
compare
when
the
solution.
next
was
of exudation showed
one,
solution
the
the solutions
conclude that it
of exudation showed
experiment,
the
the effect
compared
was
however,
must
of exudation
rate
Hoagland
of
the
sucrose
case
We
has
sugar
effect.
Hoagland
of
only
sufficient
preceding experiment
equilibrium
in
an
enhancement
the
the
exudation
of
of
observed
before
containing
salts.
secretion
condition
consisted
the
one
simultaneous
throughout
of
the
solution
a
be
time
cause
mannitol lacked
solution
more
always
some
mannitol solution;
sucrose
account
decrease
the
may
takes
(fourth period)
present
might
usually
was
b
generally
was
difference whether the
no
solution of
than
roots
sucrose
exudation
sucrose
result
of the
in
up
with that of
makes
The latter
apparently
Experiment
of
is
experiment
lighting.
minutes.
on
on
The
sucrose.
11.00
than that of material
green-house.
sugar
been
are
sucrose
»
influenced
the
the
8
exudation
(0.022 M.)
>J
the
alternately
this
time
+
of
put
was
the exudation in
on
on
always be ob-
not
salts and either mannitol or
sucrose
roots;
of exudation
where the results
instance,
TABLE
Mannitol
rate
last
unmistakable.
Influence of
H
into the
up
that the increase
the osmotic
as
the
promoted
was
periodicity.
experiment
which
eliminated,
of
it
salt secretion
proves
by
table 8
containing
effect
but
great
caused
in this
as
shown in
isotonic solutions
favourable
of behaviour
in
of the exudation
course
way: the
the salt secretion and
out
not
experiment
an
had
solution
is
ANDEL
that had been taken
sucrose
gave
effect
strong
This is
unusual
pattern
sucrose
VAN
14 in this
experiment
supply of sugar
solution
not
the
explain
can
period
M.
be
a
replaced
by
a
Hoagland
sudden increase followed
expected
for
a
decrease
in
by
the
THE
INFLUENCE
value of the
osmotic
concentration.
whereas
An
we
equilibrium
of exudation
to
salt
should
attribute
the
this
medium in
acts
as
but
as
soon as
in
It
so
secretion
12.
solution
long
of
can
runs
the
by
in
a
by
an
however,
substituted
for
increase
was
a
483
PLANTS
in its
much
mannitol
salt
greater
solution,
but
a
strong
to
the action
period.
of
in
decrease
sugar
This would
taken
mean
the
rate
plausible
seems
up
that
from
sugar
be taken up. At first the exudation is stimulated
14
the exudation
must
decrease
again
as
the
out.
rate
outer
the
OF TOMATO
approximately 20 minutes. It
osmotically
Changes
was
preceding
that the
as
accompanied
phenomenon
the
EXUDATION
increase,
attained
not
was
THE
smaller increase because of the
periodicity.
a
expect
experiment
appears
sugar
ON
gradual
in after
salt
of sugar
supply
Fig.
set
SALTS
medium
The
when the
than
OF
active
rate
solution
of exudation
solution did
of
of
substances
exudation
sucrose or
was
not
not
influenced
contain salts,
promoted.
caused
nor
The
by replacing
mannitol, lacking salts.
a
by
was
results
the
the
of
salt solution
484
similar
two
when
cases
points
vessels.
the
the
It is
that
of
acid
furic
No
by
well
as
was
sugar
solution
This
sugars
as
of the
when
even
of
sucrose on
as
rate
of
the
exudation
with
compared
h
.
H
b
.
.
We
to
the
20.6
That
First
in
that the
by the
an
seem
with
seemed
the
uptake
of
of
presence
effect of
very
plant had been
It
on
to
might be that
It
is
known
roots.
Broyer
This
roots
plants
if
several
maize
more
plants
H
(0.015 M)
25.6
0.37
+ Sucrose
H
0.73
Sucrose
+
22.6
stimulation
any
by adding
influenced very
not
was
exercise
exudation
were
present
has
is
was
of
roots
were
so
taken
this
was
been
added
with
while
of
Arisz
taken
the
to
and
up
if
as
on
the
by
out
not
however,
course
after
of
the
absent.
exudation.
promoted.
Hoagland and
found that
(1936)
as
It
(Humphries
low
has
1951)
1950;
was
favoured
the sugar condition of
to
medium.
of
explained
we
were
is
stated
could
the medium is
pointed
glucose
was
we
solution
salts
sucrose
from
Helder
of salts
(1950)
It does
not,
This indicates
up
Prevot
barley
why
outer
much bromide
as
plants
the
unexpected.
of the unusual
the
uptake is related
already
Lowe
explain
lacking.
to
action
of salts
presence
tomato
because
added
Steward and
was
that the
solution.
uptake
salt
it
when
only
rather
was
Street and
This would
been
explain
Andel,
phosphate
the
were
could take up
glucose
sucrose.
by
sucrose
the
much
influence.
some
only when salts
the
possibility
of
when salts
has
investigations
(Van
the
that this
that the
(1936).
barley
salt
lacking
Sucrose
3.2
influence
to
salts
a
sucrose
It
the
M
that effect
phosphate.
sucrose
difficult
is
sucrose
certainty.
sucrose
probable,
that
a
14.4
Glucose could also
uptake
the exudation when
above,
sul-
(0.014 M)
0.90
demonstrating
produce
consider
importance for
find
to
it
state
must
and
but because of the smallness of the stimulation
sucrose
we
on
in solutions
23.4
solution contained salts beside the sugar
outer
the
Hagedorn-Jensen.
H
7.0
sucrose.
The sugars seemed
in the medium,
to
in
for
sap
medium.
the addition of
difficult
and
happen
of mannitol
(0.015 M)
M
The exudation of Sanchezia
by
salt secretion
0.48
M
+
succeed
not
into the
9
and
15.2
.
did
glucose
also
had been
plants
M
0.86
Medium
.
This
sugar.
a-naphtol
method of
the influence
21.6
.
S
15é
and
would
reaction with
(0.015 M) (0.015 M)
15a
must
hours.
H
.
salt
Medium
Experiment
.
this
as
the
TABLE
Influence
We
secretion of salts
investigated by examining
was
means
9.
only been found in
the vessels
permeates into
sucrose
by following
found,
several
for
the
on
stronger exudation,
the absence of salts.
presence
acts
table
has
sucrose
contained both
sucrose
probable that
not
of the
cause
solution
outer
in
recorded
stimulating effect of
a
the fact
to
VAN ANDEL
been
have
experiments
emphasize that
is
M.
O.
been
as
to
salt
sugar
shown in
well
Helder
added
high
salt, high
as
with
1952)
that
the medium.
THE
According
INFLUENCE
the
an
fact
it
the
the secretion
increase
is
effect
in
THE
When
be
to
reduced
a
given off.
secretion is
value
was
of
off
lower salt
a
of
the
medium is
when
the
osmotic
M
(second
was
still
small
on
a
can
(eighth
last value how-
periodical
decrease
solution also less salt seemed
Hoagland
other
The
of
period).
increased
more
because of the
value
experiments
also
show
that the salt
the osmotic value of the medium
as
also be
in the
seen
was
following experiment
determined
on
various
non-
H
The
while the
still
has
plant
enhancement of the
compare
was
H +
(0.5
some
H
same
we
not
increase
amount
of salt
concentrated
a
on
M)
did
the
osmotic
see
salt
conditions
that the
higher
favourable effect.
0.5
that there
secretion
it
is
are
of the
by
mean
the
by
effects:
higher
the
that the
H + M
M)
0.61
opposite
two
decreased
medium. This could
0.5
(0.031
0.89
stimulated
is
H
(0.012 M)
0.76
hand
we
an
secretion
given off under the
(0.030 M)
0.83
seems
by
salt
However if
concentration
2
(0.012 M)
result
accompanied
16:
Experiment
the
2).
with that
concentration
other
More
changed.
not
value
secretion
0.023
medium.
the vessels
to
but
It
of
medium is
4,
now
the
(2 H)
salt
osmotic
16). The salt secretion
solution
S
concentration is
if the
the salt
to
too
since
(compare experiment
0.5
that
value of the
enhanced
However
concentration
at
alterations
solutions of different salt concentrations. The increase of the
osmotic
salt
observe
can
progressively reduced
(experiment
given
influences
point later.
of
% could be observed.
35
to
is further enhanced. This
salt
result
of the salt
experiment
was
be somewhat
may
isotonic
a
an
that
MEDIUM
value of the medium
reduction
of the salt secretion,
be
salt
off
in
%
solution
When the osmotic
to
as
was
suppose
always
this
to
that
means
sometimes considerable. Thus the salt secretion
was
75
to
Hoagland
ever,
we
return
of
time before this
much
of salts
presence
we
stimulation
a
so
time the osmotic
the
given
by
takes
will
THE
If
also
expect
cause
mentioned
cells
root
stimu-
again.
The reduction
period)
OF
table 2
when
even
caused
We
the
the vessels.
that it
secretion
VALUE
decrease every
proves
lowered
was
salt
considering
enhanced,
salt
in
OSMOTIC
to
appears
in
just
know if this
not
into
the
whereas
immediately.
Changes
§ 5.
curious
seems
noticeable,
the exudation
of salts
be
should
we
investigations
most
do
we
the exudation is
then it
uptake,
and
particular,
as
485
PLANTS
especially would be the
the accumulation of ions
was
in
increase
here,
importance
increase of the exudation. In
however,
OF TOMATO
uptake of nitrate would also
be of
might
EXUDATION
increased secretion of nitrate
stimulated in
a
THE
SALTS ON
Humphries the
to
lated. The last
that
OF
salt
higher
0.5
H
(0.012 M)
0.87
on
the
one
side
the
on
the
of
the
concentration;
osmotic
pressure
uptake secretion is stimulated
higher salt concentration of the medium while
as
the
486
O.
tissue
secretion
processes
the
to
is
extent
same
secretion
that
at
more
vessels,
higher
the
sap
inhibition
an
and
Uptake
of
of
the
whole
tissue
solution,
again.
secretion
to
isotonic
an
This
inhibition
of the salt
solution.
to
could also
value
should
end
when
be
of the
salt into the
be
plant
a
The
was
on
secretion
plant
a
and
isotonic
an
solution
of mannitol
only,
TABLE
Changes
in salt
secretion resulting
from
had been enhanced
which
of the
given
Osmotic value
medium
by
replaced
was
changed in its
was
osmotic
Amount
Experiment
uptake
transferred
10
changes
Amount
solution
the
then
was
much
Hoagland
Hoagland
a
true
solutions
outer
the addition of mannitol. After half an hour this solution
by
were
expected.
determined how
we
tissue
calculated.
They supposed
secrete
concentrated. If this
Hoagland solution whose osmotic value
a
stimulated
solution of mannitol and
the
gave
this
the vessels
to
not
determined in
were
To
an
outer
secretion
secretion
values.
that both
imagined
values.
required
more
salt
be
secretion is
found
be
perhaps
would become
given off
was
osmotic
Van Nie also
would
different osmotic
salt
lower
also
can
uptake
osmotic values of the
energy
as
it
that the
so
at
as
Arisz, Helder and
VAN ANDEL
but
hampered;
hampered,
are
M.
value
of the medium
of salt
of salt
off
given
off
on a
Difference
on an
isotonic
Hoagland
(... uptake
mannitol
secretion)
solution
solution
16a
164
for
turn
M
0.70
0.041
M
0.49
0.014
M
0.71
0.014
M
1.56 5
0.052
M
1.26
the solution
experiment
solution
to
exudation
the
and
of salt
plant
was
5
salt
secretion
as
0.29
0.23
0.25 5
0.42
0.29
0.56 5
0.71
0.55
At
mannitol, again.
once
put
more
been
the end
of the
ordinary Hoagland
an
in
changes
any
result of
a
on
6
0.41
1.00
whether there had
see
or
5
0.014
periodicity.
the
There
rate
were
of
no
such
16a and
variations in experiments
b, so the values found for
uptake and tissue secretion may be considered reliable. It was now
possible
the
proved
first
showed
taken
to
(from
a
of
higher
osmotic value.
M
in
0.052
to
The
does
on
in
0.067
a
M
from
0.042
solution of mannitol,
the
salt
secretion.
M
The
value
as
it
The
secretion
of the
10).
medium
was
0.565
to
secretion
It
when
uptake secretion
amounted
tissue
(table
on
this
a
to
transport
not
the
Although the osmotic value of
to
0.71
tissue
in
however
appears
that in
from the tissue when the osmotic value
higher.
medium
M,
the latter.
1.00
and
uptake
the osmotic
to
given off
solution is
the
values
when
from
salt is
from
a
0.55
to
decrease
less
outer
up
change
0.0i 4
and
case
particular
of the
solution had
not
enhanced
the
calculate the
to
outer
seem
sap
to
in this
Hoagland
cannot
be
the
be
the vessels
of salts
affected.
experiment increased
solution
cause
and
of the
0.039
M
decrease
THE
It is
possible
This
way.
INFLUENCE
OF SALTS
influence
to
EXUDATION
487
PLANTS
OF TOMATO
of the salt secretion in this
part only
one
that
supposition
our
supports
ON THE
different
two
are
processes
involved.
The
be
to
the result
as
in
seen
nitrate
the
phenomenon, of
same
the vessels
off
the
to
the nitrate assimilation.
stimulated
the
The
In
influence
sections
preceding
It
is
of the
part
Rosene
salt
exudation of
(1944) also
(0.001
Rosene
of which
was
of exudation
after
does
rate
for
a
first
that
to
to
our
advanced
that
two
the
to
mechanisms
of inhibitors.
be
inhibited
be
can
(1942)
inhibited
the
at
imply
an
same
exercise
thought.
plants
an
suffered
roots
one
the
rate
for
not;
was
hypothesis
inactive
first
at
cyanide,
of Rosene’s
(that is osmotic)
(1949,
1950) found
but
promoted;
if the inhibitor
in-
involved,
influence of the
Lundegardh
was
reversibly.
stimulating
a
would be
level. This
active and
certain
a
higher concentrations
at
processes
addition
by the
allowed
was
that
to
act
longer time.
exudation
dation
17
on
was
our
intention
as
investigate
to
well
the presence of salt in
was
rate
again
an
isotonic
again,
added.
The
when
compared
were
on
solution
M)
the
solution,
added,
and
immediately.
minutes
It
13).
the tissue exudation
secretion
solution
(0.0005
decrease
on
as
an
This
rate
solution
equilibrium
caused
of decrease
the
can
of
rate
plant
of
was
exuon
a
of mannitol. When,
had
rate
slowed
diminish
been
attained
of exudation
down and
almost steady.
was
Hoagland solution with 0.0005
for the concentration of KCN
the
part
the medium. The
a
of exudation
a
the
on
first examined under normal conditions':
salt
Hoagland
KCN
(fig.
depending
was
and
Hoagland
new
was
later.
transfer of salts
Van Overbeek
under the
of exudation decreased
the exudation
25
been
KCN while the other
Van Overbeek
Experiment
a
comparable
explanation
means
could
two
decreasing
stayed
influence of KCN
on
medium
exudation
the
by
of
when the
concentration
that the exudation of Allium
that the exudation of wheat
the
the
salt
insight into their
can
to
concentrations
necessarily
as
process,
has
influence of KCN
supposed
sensitive
at
time
some
not
stimulation
a
in
the
seems
the
plants
tomato
stated
Lower
M).
fluence.
secretion
According
inhibition under the
an
better
that the exudation
the medium.
to
on
is
and
cyanide
known,
of KCN
This
hypothesis
a
to
nitrate
involved with
gain
the
influencing
Potassium
a.
the
to
this
Lundegardh’s
inhibitors
may be
vessels. We have tried
salts.
discuss
of
into
potassium
thing occurred
enhancements of
of
will
of salts
glucose concentrations of
same
calcium
or
smaller
Less
(1945).
higher
at
However the
secretion
different processes
through
tables
sap
potassium
We
16.
experiment
§ 6.
of
whereas
high,
very
the secretion
Lundegardh attributed
solution.
concentration
decrease in
a
higher osmotic values of the medium,
Lundegardh’s
given
was
outer
of
At
M
that time
KCN,
rapidly
in
a
to
after
a
was
non-
488
O.
alkaline
solution that is
the
of decrease
rate
renewed the
been
VAN
ANDEL
well aerated. This
might be the
the
slowing down. When
was
of
rate
M.
exudation did
decrease
indeed
why
reason
solution had
outer
somewhat
further.
After
the
The
to
the
made
was
solution
Hoagland
13.
Fig.
had been
plant
investigation
Changes in
the
solution.
outer
to
rate
as
much
the
The
KCN.
to
hour later,
an
again,
rate
of exudation
course
to
In
to
12
rate
13
fig.
of
in
present
we
the
that
can
caused
by
depending
decreasing
seventh
to
the
the
We
moment
The
of the
the
is
a
and
rate
active;
was
of
but
exu-
when,
given
once
under
the
influence of
remarkable resemblance
13
must
of
to
uptake
salt
when
the
of salts
solution
The
salts
rate
out
by
salts
that
to
be
tissue
even
a
false,
rate
that
if
since
of
exu-
the decrease
solution without
of exudation
were
The
were
had been inhibited
however
point
diminished
rate,
any
decrease of the
big decrease then observed
medium,
no
indicates
at
than
simple
solution.
when
sec
This
proved
really is.
be less
Hoagland
inhibited
however
a
a
mm/30
further
a
to
of exudation is
period).
the
uptake secretion would
seems
rate
added
to
supposition
replacement
period).
change
decrease
partially
on
salts appears greater than it
at
how
induced
period).
the
M.KCN
increase.
any
inhibition of the
(second
been
have
The latter
(sixth
hardly
the situation
amounted
the removal of salts
dation
an
see
medium
must
completely.
con-
conditions
in the
still
was
decrease bears
when KCN
sec
the exudation
decrease
secretion
to
of 5.10-4
normal
an
occur:
of mannitol
addition
under
hour,
KCN.
resulting
proves
However,
exudation
exudation
the
the
by
one
could still
solution
a
effect
of
presence
uptake
of this
suppose
mm/30
salt
for
effect
by the removal of salt from the medium. One might
be involved here.
this.
of the
salt
Hoagland solution (with KCN)
a
The
that caused
by
of exudation showed
rate
be inclined
the
and
dation indicated that the
half
a
of exudation caused
Comparison
KCN
solution of KCN
a
whether
replaced
was
in
taining
on
see
removed
must
but the value attained in
was
(sixth
still
and
be attributed
the condition
INFLUENCE
THE
of
equilibrium
of
exudation
SALTS
OF
ON
controlled
was
by
from
resulting
EXUDATION
THE
factors
two
the
lack
inhibition under the influence of KCN.
that
the
of exudation did
rate
wards, salts
added
were
but
nished,
otherwise
when KCN is
added
it
show any
not
the decrease in the
decreases
b
not
experiment k
this
be
will
made
The
After
that
appeared
a
decrease
change
A
be
used in
in
as
case
a
When the
partially
It
the
inhibition
the
sensitive
only
not
all
at
be
when
that less
in the
the
minutes
at
the
put
be
on
was
same
the
a more
to
plants
were
the
rate
rate
half hour. A
a
KCN,
was
experiment
was
extent
as
added
constant,
the
the increase
rate
in
accompanied by
although
to
con-
exist
to
material
The
was
a
In
well
the
complete
reversible.
from
medium.
the
found
that
not
continued
17
in
few minutes
rate
detail
were
not
during five
was
sap
so
not
changed
more
of exudation
sample of
long.
so
indicates
of exudation
it
from
taken
plant
was
that k could
of exudation. The
rate
of exudation
medium, but the osmotic value
the salt
rate
the
with
cause
(1953)
in table 11. The
the
solution.
outer
value. Then the
secretion
of exudation.
the
an
given
It
used later and
investigated
was
but the average
are
reduced.
the vessels, but also that k is
This
seem
exudation recovered
experiment
determine its osmotic
remained
sap
Conversely
an
not
possibility
of Vicia Faba recovered
concentrated solution for
if KCN
same
point
experiment.
green-house.
not
fairly
Brouwer
changes in
determined every
time
lit
might
calculated from the sudden decrease in the
the
),
In
too.
appear
were
removed
was
that
to
KCN.
the
way:
continuously,
decreased,
to
which
used the
were
experiments
given off
influence of
data of such
of
salt is
the
to
KCN.
to
artificially
mentioned that
already
following
followed
m
b
ordinary green-house,
an
plants
KCN
observed,
with KCN. Our
has been
under
plants
furthermore
being
plants
took sixteen hours before intact
It
O
completely by using
observed
never
in
grown
in
this
M). Big differences
sensitive than the
more
or
treatment
was
of individual
that had been
however
may
—
this
but this took several hours
concentration of 0.005 M KCN
inhibition,
of
cause
[O
to
meantime
the
KCN had been added
which had been cultivated
first
in
was
(0.001 M)
soon as
(0.0001-0.005
the whole less
on
k
reckon with the
must
inhibit the exudation
to
sensitivity
1951,
=
half the exudation did
a
we
of KCN
possible
used
between the
conclude
only
decrease
in
inhibited
partially
stimulation of the exudation
centrations
the
must
that
the vessels ;
to
must
we
be
not
dimi-
was
appears
determined. Fuller reference
further, although
any
set
given off
changed, k
not
hour and
one
concentrations
higher
is
m
only
was
concentration
to
O
not
was
approximately
the
—
after-
later.
exudation
decrease
to
O fc
It
since if in the formula b
exudation,
while
medium
changes.
that the reduction of the salt secretion may
the fact
by
when,
The osmotic value of the
salt is
because the osmotic value of the sap did
rate
prolonged
the
much
very
concentration of the
did
the medium less
to
decrease in the
and
This is indicated
increase
not
again (eighth period.)
decreased when the salt
sap
the
:
salts,
of
489
PLANTS
OF TOMATO
therefore
K also showed
of exudation after
a
changing
decrease.
the removal of
increase of the salt secretion
as
well
as
ofk.
490
M. VAN
O.
The exudation of Sanchezia
of KCN.
in
The
of this
course
17:
experiment
the
ANDEL
nobilis also
change
decrease
decreased
identical
was
rapid
was
that
but
first,
at
the addition
on
to
described
afterwards
slowed down without altogether ceasing during the experiment.
well
as
secretion
uptake
as
effect could
still
occur
and
one
of
and
KCN
DNP
of
rate
on
Tissue
distinct
a
salt
half hour after KCN had been added.
a
TABLE
Effect
although
inhibited
was
11
salt
exudation,
secretion
and
conductivity
for water
Medium
Exp.
17a
Mannitol
0.005
M
KCN
Mannitol
0.005
M
distilled
18a
10*
M
So
we
bition
to
800
11.30
7.6
0.019
0.14
540
12.00
7.0
0.020
0.14
560
12.30
9.0
0.020
0.18
620
0.19
660
0.13
360
water
10.15
6.5
0.020
0.13
241
10.45
7.5
0.024
0.18
289
11.15
6.0
0.022
0.13
241
11.45
4.5
0.021
0.09
144
12.15
4.7
0.020
0.09
151
12.45
5.1
0.020
0.10
187
13.15
6.4
0.020
0.12
244
the
of
solution
cases
so
The
KCN
that
after
was
complete
so
that there is
time the
causes
be
cannot
It
complicated.
are
has
KCN is
added
rate
of exudation then decreased in
fig.
13,
KCN
added
was
The whole process of salt
say,
if this
KCN is added,
a
osmotic
Although
shown
effect
by
of
both
13
the
roots,
uptake
to
a
in
must
solution
as
way
(fourth
uptake
but
also
the
factor
and
tissue
that the first
become
and the
very
is
by
can-
decrease
not
only
decrease in
of the
water
k.
secretion
inhibited
small
We
place immediately
consequent
a
the
when in
period).
be concerned here.
takes
the
clearly
without salts:
same
its
way,
that
already
secretion. This is
the
Hoagland
similar
a
out
solution
exactly
secretion
sap,
course
inhibition of
an
because the decrease then observed is caused
of the
had
used. The
were
pointed
decrease in the salt secretion
value
by fig.
a
secretion
reduction of the salt
conductivity
to
reason
affected,
of exudation did
rate
explained
been
tissue secretion is inhibited besides the
demonstrated when
no
not
the removal of salts from the medium.
resulting from
however,
have
recover
the exudation. The inhi-
much like that caused
very
to
removed.
was
inhibit
some
must
proved
certain part of the exudation process is
found
decrease
that here k
secretion
salt
can
be
to
change,
not
and
exudation
some
a
the salt secretion
salt
840
0.26
0.021
water
proved in
of the decrease
the
0.27
0.022
decrease further when weak concentrations
not
by
0.023
11.6
0.022
Both
suppose that
not
11.8
11.00
8.6
when
we
10.30
99
too.
k
6.4
have found that KCN
although
S
13.30
The osmotic value of the sap did
fairly well,
o„
13.00
9 9
decreased
b
KCN
DNP
distilled
time
two
to
hours
were
a
inhibited,
greater
after
extent.
KCN
had
it
is
The
been
THE
added.
INFLUENCE OF SALTS ON THE
While
decreased
the
from
of exudation
rate
13.2
EXUDATION
mm/30
on
5
to
sec
be
since
surprising
so
it is
completely inhibited by
for instance
(1944)
was
fully
KCN
would
of wheat
respiration
of salt
b.
uptake
will
two
inhibit
entirely
found with
(1950)
by barley
hours with KCN.
uptake
the
an
M.
anion
of anions.
tissue
carrot
roots
O.OOOl
Again
inhibition
KCN.
by
2.4-Dinitrophenol
The
action of
qualitative
did
2.4-dinitrophenol
much from that of KCN. Like KCN it caused
of exudation that
contained salts
not
changed.
the
same
certainly
were
be
the
as
inhibited
in
present
the
effect
same
the
of DNP.
14
Fig.
Rate
proximately
one
removed
gradually:
but
It
is
from
difficult
was
inhibitor
very
—
Periodical
cially
half
14.
to
experiments
dation
of
after
Fig.
these
in
that
the
both
exudation
the
17:
of salts
with
the
secretion
and
plant
secretion
of exudation
medium,
Influence
say
to
of
it
the
had
rate
not
dinitrophenol
what
the salt
by the periodicity. The fact
at
that
were
the
beginning
periodicity
rather
green-house
small
as
will
is
with
be
—
not
ap-
the inhibitor had
increased
effect.
the exudation
extent
were
to
completely recovered.
yet
on
of
the salt
decreased
the
hours
salts
part
investigated
After
two
to
in the presence
tissue
secretion
was
must
no
the
on
same
rate
solution
changed
was
conditions and
salt
the
value of the sap
secretion
the exudation when
uptake
and
outer
The tissue
uptake
differ
to
prove
during the experiment.
indicates
illuminated
on
under normal
regular
changes
the salt
affected
experiment
shows
diminished.
been
depends
as
way
DNP
as
that
of exudation.
rate
when
The osmotic
not.
not
decrease in
a
medium. The influence of DNP
investigated
was
did
follows from this,
extent
both
immediately,
when it
as
It
in
set
the exudation that
in
is
perhaps
of salts
uptake
of bromide
uptake
of
which controls the
roots
Weeks and Robertson
that the
Lundegardh
to
This
0.21.
to
had
tissue secretion
similar concentration of KCN. Machlis
a
a treatment
according
the
sec,
0.52
expected
that the
found,
inhibited after
be
to
491
PLANTS
solution without salts
a
mm/30
itself had decreased in that time from
not
OF TOMATO
is
that the
influenced in
rate
of
before
addition
very
important
plants
exu-
of the
here.
grown in the artifi-
demonstrated in section
7.
492
M.
O.
In
these
that
the
for
such
experiments
the
decrease
in
the
of small
possibility
experiment,
be
sensitivity of plants
The
concentration that
same
in other
cases
it
inhibitor,
especially
proved
used in
inhibition of 15-20
an
so
is
probable
secretion
end
is
k,
the
although
the
at
and
of the
altogether.
out
DNP
to
was
the
by
changes
ruled
salt
exudation,
caused
periodical
cannot
used,
chiefly
were
of
least
at
greater part
plants
rate
ANDEL
VAN
be
to
rather variable.
18
experiment
(fig.
only, which
%
The
caused
14)
completely
was
reversible.
It has been
should
pointed
under
change
not
therefore be
the
actually
was
It
the
found
only
of
It
an
to
should be
Sodium
the
the medium
find
the
vacuole
19
(distilled
a
have
of the
times
decrease
The
of
Vallisneria,
proved
be
inhibited.
caused
immediately
did
given off
roots
must
water.
water
to
its
more
once
From
and
mentioned
and
the
This
tissue
experi-
transport of
to
the vessels.
on
the
but
the
not
transport
secretion
change,
arsenate
rate
off in
with KCN
so
in this
of
the
same
and DNP.
case
and
too
the
—,
After 40
replaced
the
water
plant
was
minutes this solution
rate
of exudation
this
time
—
caused
was
the
—
not
half
an
transferred
proved
Addition of Na-arsenate
concentrated
after
less
water
have decreased. The exudation did
was
to
exu-
a
changed
to
have
solution
exudation
to
again.
inhibition
stayed
of the
from the tissue
—
distilled
value.
sodium
passed
experiments
again. Now the
initial
M
decrease
a
caused
by
Na-arsenate appears
is remarkable that the exudation recovered
on
a
salt
solution
Warburg and Christian
enzyme
by
transport
of
(1953)
DNP.
that the
concern
the
while
cannot
Arisz
uptake
cytoplasm
in
set
solution.
Hoagland
increased
had
this
by tentacles of
Weeks
however,
Weeks
to
uptake
of salts
influence of DNP
described in the
been
by distilled
but it
inhibition
when the solution of Na-arsenate
distilled
ten
Wilkins and
and
any
water)
This decrease
conductivity
for
of k
that
explained
we
asparagine
-5
15). Addition of 10
(fig.
that has been
recover
as
the exudation.
and
experiments
our
The osmotic value of the sap
to
shows
arsenate
Experiment
must
in
understood
clearly
Wilkins
not
through
into
dation.
did
(1953)
decrease
phosphate
Robertson,
the vacuole and
of chloride
of salt
of
simultaneous
of Robertson,
Arisz
hour
decrease
A
18a)
decrease of the salt
a
inhibition of the transport
the
explain
ments
the
uptake
inhibited.
was
secretion.
salt
(exp.
1951), but
Weeks,
KCN,
of
of
cause
possibility
would
way
11
case.
Wilkins and
that the
Drosera
c.
value of the sap did
dinitrophenol.
Table
expected.
the action
discussing
salts
of
uncouples respiration and phosphorylation
uptake of salts by carrot tissue is inhibited by DNP
The
(Robertson,
the
influence
known that DNP
is
processes.
be
that the osmotic
already
out
the
systems
that
for
(1939)
arsenate
can
some
to
be
reversible,
only after the plant
time.
found in
replace
experiments
inorganic
on
isolated
phosphate
in
THE
oxidative
the
the
overcome
TOMATO
coleoptiles
but that
by Na-arsenate,
by adding phosphate
is
phosphate
of Avena
growth
493
PLANTS
uptake of inorganic
inhibited
was
OF
to
the medium.
light of these data it seemed probable that the reversal of the
inhibition described
of the presence of
Fig.
EXUDATION
stated that the
(1950)
by indole acetic acid
arsenate
been
which
Bonner
this inhibition could be
In
THE
OF SALTS ON
for
reactions,
necessary.
induced
INFLUENCE
19
experiment
Reversible
decrease
of the
rate
of
would
be
solution. It
Hoagland
that exudation and salt secretion
proved
15.
in
in the
phosphate
did
not
exudation caused
the result
has
indeed
recover
on
a
by adding sodium
arsenate.
solution
all
containing
of
exception
the salts
On
phosphate.
dation could be observed if
land solution
;
if
a
section
phate
was
fluence of
It
has
creased
3
in
arsenate
this
the
the
uptake of salts
fig.
19.4
16 it
is
mm/30
sec
for
arsenate
caused
reversed,
but
18.4
a
to
a
to
10~ 3
14.4
further decrease
to
to
13.6
to
used the
unimportant
investigate
19
phos-
the in-
on
the part
mm/30
of
in
rate
sec
small
arsenate
mm/30
10.6
sec
the
to
a
mm/30
made the
rate
sec
rate
if the
governed
by
of
could
In
decreased from
Hoagland
that
deThe
described before.
of exudation
when
the
solution.
outer
the exudation
the way
decrease,
and
secretion
that the tissue
Na-arsenate
of mannitol. The addition
very
M
was
itself is
solution without
designed
the
exu-
complete Hoag-
a
phosphate
Hoagland
investigated
was
solution
a
added
without
experiment
demonstrated that the
changed
from
reason
addition of
influence of Na-arsenate
the
decrease of the
no
exudation.
on
been shown in
on
hand
was
experiments
solution with
Hoagland
a
(the absence of phosphate by
For
a).
used
arsenate
Hoagland solution
exudation decreased
c.f.
from
the other
solution
10
be
-4
M
was
Na-
completely
of exudation decrease
of exudation
showed
Hoagland solution
was
a
now
494
O.
replaced
by
osmotic
mannitol
a
of the
medium
0.042
M
to
0.036
M,
when
and
16.
was
Influence of sodium
absence
of
salts.
secretion
uptake
drawn
In
must
in
reckon
addition
decrease
d.
of
rate
Sodium
with
the
the
to
of k
has
plants
of
arsenate
lead
changes
of
1950)
could
but
present,
has
presence
added, in
have
in
become
cause
a
a
been
smaller
that
smaller.
case
The
smaller decrease
salt
secretion
on
be
that is
the
under
an
solutions
by
of
influence
Lundegardh
great increase.
not
linked
dent of metabolism.
of
considered
an
to
anaerobic
of
of
it
cations
now
the
to
Later
given off
to
but
the
the
of the
to
vessels.
experiments
that
appeared
NaF,
unimportant.
the
rate
vessels,
did
secretion
of
proved
to
even
supposed that the exudation
glycolysis but that it
was
The decrease in the exudation of sap
inhibition
young
of the exudation
The nitrate concentration of the sap
not.
of
exudation
glycolysis.
water
show
was
was
since
conclusion,
amount
the
sensitivity
exudation
controlled
the
that
in concentrations of 0.01-0.001 M.
concluded that the
another
decrease
result
was
found
by NaF
did
the
the
was
M.
of exudation and
rate
nitrate
of salts
tissue and
demonstrated.
inhibited
would
to
exudation,
a
arsenate
conclusion
that k
possibility
been
depend
process
indeed
This
both
that the removal of salts caused
secretion could then
(1949,
was
would
(1950)
10-3
to
fluoride
Lundegardh first
This
sodium
M
0.042
the mannitol
of exudation in
rate
M
decreased from
from
that
means
and following periods
The osmotic pressure of these
NaF
the
10-4
concentration
exudation.
Lundegardh
wheat
period
value
and
The
arsenate).
replaced by
was
This
on
arsenate
exudation if
of the
period
solution
diminished.
are
the osmotic
arsenate.
fourth
sixth
decrease of the salt
the
In
a
the
containing
when the salt
only
the second
from the fact
already
decrease
same
in
Hoagland
the
we
changed
sap
M
ANDEL
(also
lowered. Thus
0.038
the
VAN
solution
the presence of
solution in
Fig.
the
value of
M.
so-called
“extra-water”
indepenwould
be
secretion.
THE
the
INFLUENCE
exudation
could
water
of
in
and
M
in
exudation
12.
The
a
M
M.
the result
dation
the
proved
and
with
to
those
use
mannitol isotonic
same.
The
necessary
Instead of
present.
which
Ca(N0 )
0.005
M
3
KN0
and
the
by adding
than
concentrations
all,
when
even
when
even
of
replaced by
0.0005
they
greater
Ca
M
ions
0.005
were
KH
does
M
the
addition
of 0.01
M
of the
a
and
osmotic
NaF, compared
osmotic value
with
It
with
one
has
the
Ca
used
was
solution
a
in
containing
been demonstrated
.
the
exudation.
affect
not
impossible
was
Lower
the exudation
at
for several hours. Sometimes
act
of NaF
or
affect
did
to
solution
3
not
NaF
allowed
amounts
of exudation
rate
by
fluoride,
concerned. So
was
precipitated
KN0
P0 4
added
were
TABLE
in
Changes
from 0.036
replaced
was
the
table
added
was
rose
mannitol. It
fluoride
as
2
absence
in
the solution of
osmotic effect
an
3
that
NaF
sap
high
impede
make the solutions without NaF isotonic
ordinary Hoagland
had been
2
0.005
such
of the change in the rate of exu(a sudden fall followed by a gradual
that
to
solution
an
using
is shown
M
solution
with
plants.
course
which contained it
Hoagland
a
This
value.
extra
sap.
containing
solutions
decreased when 0.01
addition of NaF
be
to
that the
of their osmotic
increase) also demonstrated
it
is
This
total
tomato
The trouble about
while the osmotic value of the
the
was
on
of the
with solutions
495
PLANTS
processes.
with
repeated
out
When however the salt
solution of salts
TOMATO
2/3-3/4
to
were
pH of 5.2.
of exudation
solution,
0.043
to
metabolic
experiments
our
account
on
rate
salt
a
OF
EXUDATION
in
carried
were
at
THE
amount
experiments
NaF,
concentrations
to
opinion
experiments
0.01
ON
released
water
his
Lundegardh’s
Most
OF SALTS
effect
no
could
be
caused
by
12
value
of the
exudation
changes resulting
of the medium
from
sap
an
enhancement
(experiment 21).
"
Medium
0.005
M KN0
0.005
M KN0
(0.013 M)
3
0.005
M
0.005
M
0.005
M
0.005
0.005
KNOo
M
M
0.005
M
+
M
+
M
(0.037 M)
(0.037 M)
(0.013 M)
M
0.005
3
time
+
NaF
+
NaF
+
NaF
(0.036 M)
(0.036 M)
(0.036 M)
(0.013 M)
+
observed.
M
(0.037 M)
In other
action
pH
of the
of NaF.
half,
tration
did
not
if
was
.
.
.
10.40
9.6
0.036
11.05
6.0
0.044
0.28
11.30
7.6
0.042
0.32
12.00
11.4
0.036
0.41
12.30
9.0
0.043
0.40
13.20
7.4
0.044
0.33
13.50
7.4
0.043
0.33
14.20
10.2
0.037
0.39
14.50
6.0
0.044
0.37
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
0.35
.
.
.
decrease
0.01
affect
given
no
M
the
was
was
rate
set
rate
in
of exudation decreased
immediately but it
shown
decrease
at
to
be
of exudation
added
the exudation
rate
of the
medium
Thus
causing
Thus the
value
.
.
S
was
at
the
usually
slight.
The
one
.
.
experiments the
addition of NaF. This
rather
.
~o b
b
at
all
a
at
(c.f.
very
pH of 4.3; the
pH 5.2.
section
The
did
not
an
same
for
the
hour
to
concen-
change of pH
itself
3c).
of exudation could be inhibited
sap, however,
off to the vessels.
important
decreased in
by NaF. The osmotic
change. This
means
that less
An inhibition of the whole salt
salt
secretion
496
to be
proved
We
could
confirm
of the sap
value
Similar
results.
secretion
was
It
caused
NaF
of NaF
attained after
decrease
from
appears
by
action
affected but
not
The effect of NaF
at
lower
a
acetic
would
discussed
influence the
Lundegardh
inhibited
pH
and
pletely
decreased
the exudation of
A solution
ten
more
no
exudation,
observed
13,
times
with
but
rate
the
the
so
The
be
gradual
a
was
found
the great
greater
a
the exudation
al-
was
pH 5.
of
the
rate
as
the
is
known
Machlis
salt if
up
M
nitrate
JA
JA
was
at
almost
a
com-
of exudation.
M
least
at
a
influenced the
to
decrease
inhibitors.
rapid
The
gradually.
somewhat different
a
at
In
now
the inhibitor
their
first
when the
and
case
present
decrease
at
decrease
was
afterwards
continuously
in the
outer
in
that
to
course
a
slower
decreased
was
exudation
but after 20-30 minutes
concentration;
followed
proved not to affect
pH of approximately 5.
were
at
concentrated
sooner
take
not
it
substance.
0.0002-0.001
chloride and
0.0001
plants,
was
this
both
that iodo acetic
since
least,
at
by
affect
to
expected
did
roots
of exudation
as
be
to
inhibited
such
other
rate
appeared
now
was
found that
began
that
long
had
As
in
secretion
seems
value
osmotic
altered.
It
of
(fig.
at
the
solution.
concentration of the inhibitor
higher.
exudation
salt
if the
would
from that of the other
experiments
barley
more
The decrease started
was
be
uptake
however,
observed
14)
differ little
uptake secretion
(1949)
tomato
of exudation
rate
the
same
the result
exu-
inhibition
happen
not
only remarkable thing
to
It
than the weaker
the
always
to
his
up
can
the
Low concentrations
first
be
the
on
the
equilibrium
an
might
at
exudation.
uptake of salts
present.
in
inhibited
demonstrated that
(1944)
that
salt
roots
acid
uptake and tissue
that the
proved
was
pH, but
The inhibitors
acid
the
if
solution
of the medium. Lundegardh also
pH
considerably
lodo
observed
figures
it
mentioned earlier. The
influence of the
ready
the
how-
conductivity of the
outer
then
from
only
pointed out,
This would
only for
but
be
of k.
inhibitors
effect
time.
result
to
be
water
of the
pH
of the
only possible explanation
would
only the
with
osmotic
brief time;
a
the
not
decreased.
were
decrease
a
simultaneous increase
must
Lundegardh’s
increased
was
It
as
a
found
were
phenomena
the influence of the
(compare
dation).
low
the vessels and
to
of the fluoride solution.
action
his
e.
off
that Lundegardh’s hypothesis is
ever,
of
Lundegardh’s results,
given
water
the osmotic
osmotic
VAN ANDEL
concerned: both uptake and tissue secretion
not
of
amount
of
M.
O.
to
inhibited,
further
the
from
but
the
the
decrease
would
to
fig.
a
sap
only
otherwise
experiments
be
a
when
it
the
of
rate
remained
un-
simultaneous decrease
but
expected,
greater
17
decreased
considerably;
preceding
and k
decrease
appears
of
decreased
in
some
cases
of
the first
extent.
that both
removal of salts
of the exudation
uptake
from
even
and
tissue
the medium
in
secretion
caused
the presence
of
were
a
JA.
still
This
THE
indicates that the
determine
to
the salt
on
17.
the lack
completely
salt
The
was
replaced
effect
by
iodo
coleoptiles
could
malic
for
did
not
seem
It
be
to
be
f.
affected
this
by
when
malic
of
of the
acid
had
been
on
a
nor
solution
salt secretion
of
malic
the
a
acetic acid.
be
to
seems
is,
as
yet,
solution of
but
it
JA
did not
of Avena
growth
however,
acid. No
added
to
the same,
increased
for
acid,
dicarboxylic
exudation,
was
acid
of
44 hours
Bonner and Thimann
by
the addition of malic
M
a
substance,
addition
inhibition
if 0.01
of iodo
secretion
inhibition of
by
After
the tissue secretion
(the pH of the medium had been kept
even
several
change
the
outer
by adding
when the
hours.
Phenylurethane
We have up
which
is
the influence
uptake
action
prolonged
section 6a.
has been shown
acid
the
by
increase
not
without
The
KOH). Neither exudation
roots
did
overcome
instance.
The
depends
the decrease of the exudation
time, while
acetic
of exudation occurred
solution
that
solution
a
further either.
acid
as
of exudation under
occurred.
at
497
PLANTS
of the exudation that
enhanced
was
of exudation
rate
that the
(1950)
of the rate
inhibited
not.
decrease
of salts
TOMATO
fully inhibited. It is difficult
not
was
the part
extent
that has been described in
way
Inhibition
further
no
uptake of salt
what
to
OF
EXUDATION
uptake had been inhibited,
caused
by
JA, in the
Fig.
THE
INFLUENCE OF SALTS ON
an
was
are
to
known
experiment
investigated.
now
to
in
described
act
on
which the effect
Speidel’s
that this substance is
the influence of several
certain
able
to
enzymatic
of
experiments
a
processes.
substances
Following
narcotic, phenylurethane,
(1939)
had
demonstrated
diminish the exudation of several
plants
498
O. M.
while Heyl
VAN ANDEL
found that narcotics could affect the exudation of
(1930)
Sanchezia.
With
This
the
plants
tomato
decrease followed
dation
accompanied
was
exudation
on
addition of
was
exudation
corresponded
had
secretion
was
proved
showed
due
to
be
to
as
a
the
means
the
continued,
the
tissue
on
absence
less
or
the
but there is
secretion
Recapitulating
the result of
no
might
we
can
adding
of
rate
increase
remarkable
of the
uptake
changed
for
the
reason
also
state
to
a
of
exudation and
in
exudation,
the
presence
the
of the
in
the
secretion.
It
appeared
first
solution of mannitol
not
(fifth
yet
rate
cyanide,
iodo acetic acid
and
a
at
has
place
that
(seventh
same
sixth
increased
that it is
after
the
to
experiment
suppose
the
phenyl-
recovery
seems
The
increase
that
parts
phenylurethane
inhibiting substances.
that
phenylurethane
potassium
arsenate, sodium fluoride,
of
of exudation decreased
had.
both
that
when the solution of
phenylurethane
secretion
salt
The
after
of salts.
that the tissue secretion had
total
exu-
secretion.
reversible:
of
rate
with
of
rate
diminish
to
conclude
is
was
the
as
18).
experiments
salt
The action
It
before in the presence of
while
more
gradual
recovery
eighth period)
This
as
a
removal
when the salt solution
and
of the
proved
must
decreased.
removed.
exudation after
be
the
(fig.
furthermore the removal of salts from
Influence of phenylurethane
urethane
to
salts
we
and
salt
in
as
in this respect with that of the other
The inhibition
18.
course
decrease
to
the medium
to
small reduction of the exudation when
a
present,
been
appeared
added
decrease
a
As
only
was
NaF. The decrease in
lacking
phenylurethane.
phenylurethane
Fig.
same
by
solution
a
the medium resulted in
the
the
M)
Na-arsenate and
KCN, DNP,
of exudation
rate
phenylurethane (0.001
soon as
level
period).
that
time,
not
been
impossible
longer
that
time.
of exudation decreased
2,4-dinitrophenol,
or
phenylurethane
sodium
to
the
THE
INFLUENCE OF SALTS ON
medium.
Less
ductivity
of the
and salt
but
in
the
to
of salts
inhibitors
also found
(except
found in
Other
act
of
part
The
to
greater
but it
the
in
to
the
the
in
bromide
Stenlid
might
is
for
has
substances
cytochrome
on
affect
different
that
important
the
an
to
will
sub-
surface.
root
the action
investigated
The
cell
proved
these
or
been
the
at
been
important
1949).
the strength
that all
that their effect
Lundegardh
also
at
one
influ-
be
pH of the medium
also
was
we
of
can
various
plausible
to
draw
influence
points this
that
of
would be
fact
acting
the
is
that
Broyer
plants
both
cases
that the
of the
changed
decrease
by
less
of the tissue decreased.
under the influence of DNP. Such
simultaneous
stated
affected
it
possible
are
exer-
enzymatic
(1942)
was
In
deficiency.
permeability
which
several
on
(JA
narcotic
a
As
indirect;
more
affected,
thought
the
explain
might
alike
inhibition of
specific
be
about
process.
much
so
action
tomato
by oxygen
and
the
no
Hoagland and
decapitated
as
way
taken up
(1949)
way.
few conclusions
are
that
The
process.
a
the exudation
inhibitors
substances
as
only
affect
suppose
but
concerned,
similar
higher
is
undissociated molecules
1952).
metabolism
a
the action of such substances. The effect
the exudation
same
structure
of
the
transport
proto-
an
effect
of
salts
water.
In consequence of Lundegardh’s
exudation
lated
this
the medium.
to
near
be very
to
that metabolic processes
say
reactions,
supposed
localized
these substances
seems
exudation
plasm
is
probable
experiments
which
it
important
It
to
the
however,
rapidly,
1950)
cytochromeoxidase
either
suppose
very
(1949,
localized
is
have,
are
concentration of
of action
modes
excepted)
is
Beevers
From these
way
of other
important for
be
as
and
(Simon
and
of
that the
the addition
to
relation between undissociated molecules and ions, which
the
is known
KCN
roots
process
pH (c.f.
the
by
affects
that
the
the exudation
they
must
we
pH of the medium proved
enced
cises
So
decreased,
the medium
already consider-
was
inhibition
cytochromeoxidase
although
penetrate
pH value only,
the
the
substances besides KCN
of NaF. The effect
that is
the
processes.
can
stances
the
rapidly
so
Lundegardh
KCN (1952)
system by
rapidly,
as
enzymatic
the
reacts
acid).
of
investigation
that
results
surface.
is
from
con-
transport
secretion
up
considerably inhibited in 30 seconds. He concluded
of these
to
taken
water
water
minutes after KCN had been added
ten
his
cytochromeoxidase
was
say
rapid effect of KCN: the exudation
a
ably decreased
He
acetic
iodo
the
both
inhibited.
completely
It is remarkable that the exudation
of
and
vessels,
to
499
PLANTS
OF TOMATO
The whole salt
affected.
the transport
be
EXUDATION
that is
decreased;
were
cases
to
off
given
was
roots
transport
some
the first
was
salt
THE
was
stated
to
be inhibited
experiments (1949)
in which the
by high concentrations
and stimu-
by lower concentrations of indole acetic acid, the influence of
substance
seemed
Beythien
changes
on
on
the
account
(1951)
of the
and
exudation
of the
of
Brauner and
conductivity
for
plants
tomato
investigations
Hasman
water
was
investigated.
of Von Guttenberg and
(1952)
should be
that in
expected
particular
although
500
O.
bear
must
we
in
of tissue
bility
Broyer
and
exudation
mind that in
was
VAN
of
and
investigated
if
Helianthus,
the
to
a
acid
whole
be very
to
sufficient
motic
the
of the
value
salt secretion.
described
chiefly
to
not
was
so
the
with
caused
mg/L)
that the
so
on
be ascertained
The
a
os-
decrease
in
decrease of the
a
later than in
and
solution.
outer
proved
the
experiments
strong.
Periodicity
§ 7.
Authors like Hofmeister
fluctuations
off
given
rate
of
exudation
during
the
day,
so
that
approximately
others
when
and
showed
The
the
is
been
in
(1939)
weak red
minima
several
were
plants
medium
was
first maximum
rather
seems
The
came
importance for
a
also
be
and the
when
shifted
a
by
a
rise
on
the
in
with
permanent
which
maxima
decapitation.
influence.
moment
the
The
at
the
which
maxima
exudation
nature
of
of the
in sand showed their
decapitation
solution
12
(this period
hours later.
temperature.
the time of
Heimann
decapitation
was
of
which the maximal exudation could be ob-
having
exuding
in
which
at
others).
grown
nutrient
similar conclusion:
light
at
some
time
12 hours after
in
occurred,
or
the time of
investigating
and
Ricinus
plants
at
also
light,
exercise
importance: plants
the time
illumination;
left
that,
by several circum-
moment
on
served with Kalanchoe Bloszfeldiana. The
were
stated
(1939)
relation between the
observed,
approximately
could
to
a
decapitated
variable),
maxima
(1952)
of
the
light);
could
(Helianthus,
also
periodicity
constant
depending
now
also found
had been
in
grown
of temperature
plants
and
However,
thought.
had
(that
Speidel
the
(Hofmeister;
constant
influenced
of
observed
under normal conditions,
of plants
grown
by day and a minimum during the night, whereas
minima occurred
Changes
also
periodicity of exudation was caused by the alterperiods of light and darkness during growth, as Sperlich
that
darkness
and
be
fluctuations
was
is
the
exudation
Hampel
plants
kept
in
occurs
to
it
shows
of sap
that the
nation of
and
However,
was
could
amount
phenomenon
already
plants
minimum
a
Grossenbacher
1936).
have
(1893)
various
happened when the plants had been kept in darkness
day and had been illuminated overnight. This seemed to
the
indicate
this
temperature
periodicity
maximum
a
reverse
during
the
while
noon
of
the greatest
experiments.
the
Hampel,
with Helianthus,
stances:
at
attributed
(1930)
during
temperature
Sperlich
Wieler
the
Heyl
night.
and
(1862)
that
demonstrated
by
the
to
(1-10
somewhat
earlier,
the
case.
hardly changed.
was
be attributed
must
This inhibition occurred
with inhibitors
by
but k
decreased
sap
of exudation
rate
the
to
this
not
concentrations
Higher
of exudation,
rate
of
the exudation
on
small. A stimulation could
certainty.
decrease in the
acid
Skoog,
applied
in
vessels
permea-
roots.
stimulation
was
Like Lundegardh we added indole acetic acid
The influence of indole acetic
water
that of intact
found
(1938)
off
the
experiments
not
indole acetic
given
was
ANDEL
these
Grossenbacher
More salt
stem.
M.
a
stump.
rhythm could
stronger
influence
as
be influenced
more
leaves
INFLUENCE
THE
According
be
the influence
A diurnal
but also in
also
of
of
in
the
of
Changes
involved
1952), but it
intensified
When
of
such
the
and k
has
been
solution
We
see
7
in
at
7.7
mm/30
was
much
that
the last
tained
14
were
this
changed
day.
further
time,
the
to
day
The osmotic
the
(experiment
so
a
show
the first, but
last
3.2
to
So
11
be
the
seen
was
in
proved
average
mm/30
lower
of
was
way
that
nutrient
avoid
to
9.9
mm/30
the
sap
night.
was
col-
of exudation could
the
value
was
have
tomato
a
as
than
next
been
plants
minimum
more
less
first of the
must
of
experiment 24
previous
which
sec,
and
to
of exudation
have increased
to
the
rate
once
In
medium.
rate
but
by day and
found
days.
at
between
at-
was
night.
11
and
the circumstances
o’clock.
value of the sap
proved
A small decrease occurred
important
it
exudation
maximum
The
experiments
day the
evening
a
the
of the
and afterwards decreased
made,
were
same
17a).
of exudation
observation
that the
maximum
cannot
at
a
11
the second
that still
night.
rate
at
from
course
successive
precisely the
hours in these
observations
indicates
during
hours;
the
data
the
concentration of the
21.1
the
osmotic value of the
of exudation,
value observed in the
This
second
on
This amounted
actually proved
The
On
p.m.
no
to
be
The observation
that has. been carried
experiment
6
two
several
pointed
we
might
the
investigating
over
the
could
stem.
plants
exudation
with
in
present
periodicity
the
to
tomato
the
for
an
rate
the salt
with
night
during
morning.
every
than
slower
be calculated.
both
7
at
compared
lected
acid
connection
reason
section
in
it increased
sec
the
in
a
of salt
find
to
Broyer
Skoog,
of exudation.
rate
experiment 24 that the
a.m.;
During
the
manner:
of
changes
sec
when
in
1938;
been made
ever
while the
with
in
be
to
(Grossenbacher
amounts
determined every hour in
renewed
was
result
a
supposed
actually change.
that the
given of
are
described
important
does
secretion and k
following
were
rhythm
Engel and Friedrichsen
1938;
indole acetic
was,
salt
rate,
a
considered
been
repeatedly
exudation
experiments
changes
13 the results
in
out
of
also fluctuated,
just mentioned,
exudation
sap
have
irregularities
irregularities
literature
table
the
that
periodic
Friedrichsen,
that such
be
cannot
investigation has
no
applying
describing
repeatedly
result
of
that
annuus
by
and
(Engel
Speidel).
Grossenbacher found
out
that it
so
permeability
of Helianthus
left out of consideration.
from this,
appears
periodicity
seems
whether the
sap
be
the
root
unimportant, while
not
only in exudation
guttation could be influenced by
of
Broyer and Grossenbacher
Skoog,
and
It
permeability
with
be
case
illumination
1950).
plants
(c.f.
this
should
roots, that
tomato
diurnal fluctuation of
a
considered
were
cycles
of
periods
decapitation
501
PLANTS
has been demonstrated
The
intact
in
in
light might
periodicity
Heimann
1952;
OF TOMATO
isolated
as
for five years, showed
guttation.
occurs
out
conditions,
Changes of temperature
pressure.
EXUDATION
THE
(1938) the phenomenon of periodicity
of external
independent
1951,
SALTS ON
White
to
had been cultivated
changes
OF
changes
could
by
be
to
change
the end
observed
very little
during
of the afternoon. No
the
second
day.
It
O.
24c
conditons.
Tomato
d
24
nobils.
De-
at
8.30
Hoagland solution.capitaed 17.30
VAN
ANDEL
—
—
—
706 740 778 765 669 612
—
—
Ob
—
—
—
0.028 0.028 0.027 0.027 0.028 0.027
—
b
—
—
—
25.0 26.0 26.5 26.5 24.0 23.0
—
k
Sanchezia Hoaglandsolution
M.
—
b
—
—
761 725 692 708 704 704 700 554 —
—
—
—
502
—
0.029 0.029 0.026 — 0.031 0.030 0.032 0.033
—
—
—
—
24.5 24.9 25.4 25.4 24.4 24.2 23.8 20.2
—
—
‘
2.2 3.5 4.4 5.0 5.0 5.6 6.3 6.3 6.3 6.6 6.6
11.0 12.0 12.4 12.6 12.6 12.9 12.0 12.0 11.4 11.8 11.0
b
—
—
—
—
—
—
15.7 16.6 17.7 19.3 19.5 18.8 17.- 16.2 14.2
—
—
—
15.2 17.0 18.4 19.2 18.8 18.8 16.6 15.2 12.6
various
k
under medium
water
for
13
TABLE
conductivy
the
Tomato solution
Hoagland
24c
ad ed
M
Tomato
has
b
and
exudation
of
rate
sucrose
means
o,,
b
258 329 396 454 471 446 379 358 318 296 238 175 139
100 100 117 127 137 118
—
0.048 0.047 0.046 0.049 0.045 0.041 0.043 0.044 0.043 0.044 0.045 0.043 0.042
0.039 0.022 0.039 0.041 0.040 0.040
—
10.0 13.0 15.5 17.9 19.0 18.7 16.1 14.0 11.9 9.8
8.1 5.1 4.0
3.0 3.9 4.5 6.3 6.7 5.9 —
737 604 500 313 252
148 154 185 177 138 123 —
950
k
1119 945 906 869 825 800 806
0.02
Hoagland solution
24
contain g
that
*
of
in
leaves
to
been
sucrose
sucrose
b
o
0.040 0.044 0.050 0.047 0.044 0.045 0.051 0.045 0.047 0.045 0.051 0.045 0.044
0.046 0.048 0.046 0.044 0.045 0.044
b
22.9 29.7 32.7 32.9 34.6 33.2 32.6 31.3 29.0 21.9 18.5 12.2 9.6
3.7 4.0 4.5 5.3 5.5 5.5
422 403 553 561 554 483 411 350 353 355 280 217 148
*
Tomato distiled water
6
—
o
-
—
-
0.026 0.022 0.022 0.018 0.018 0.016 0.016 0.018 0.019 0.017 0.015 0.018 0.015
—
—
—
479 513 547 563 547 528
0.011 0.010 0.011 0.013 0.013 0.011 0.013
24a
1
b
changes
k
Periodic
Tomato Hoagland solution
o„
II.
11.0 16.3 14.7 12.2 11.0 11.3 8.7
8.5 6.8 5.0 3.6 2.4 2.6
—
387 568 615 694 742 658 584 580 516 503 484 436 336 274 242 219
3.4 4.4 5.6 7.5 8.8 9.8
213 200 226 232 245
254* 250* 209*
0.032 0.032 0.032 0.030 0.031 0.031 0.031 0.029 0.029 0.032 0.029 0.027 0.026 0.025 0.026 0.027 0.022 0.021 0.019 0.022 0.024 0.024* 0.031* 0.03 *
24
b
time
9.9
7
16.4 20.5 27.1 17.0 14.5 13.5 12.5 11.1 9.0
14
8
9
10
11
7.7 6.0 4.9 4.2 3.2 3.9 3.9 4.4 5.0 6.0
12 13 14 15 16 17 18 19 20 21 22
22-7
7
8
9
10
11
8.5*
15.0* 11.5*
12 13 14 15 16 17
THE
INFLUENCE
OF
SALTS ON
THE
EXUDATION
OF
follows from this first that a maximal quantity of salt
time when the
that k
7
at
have
must
of k
value
This
658
to
a.m.
of exudation
rate
changed
11
at
amounted
experiment
and
a.m.
proved
that the
so
occur,
table data
carried
with
out
in the
plants,
changes
a
water.
maximum between 10 and
The
in
changes
The
case.
magnitude
second
salt
solution
Thus
we
dation of
of salts
the
have
salts
the
the
to
medium
However
could
take
It seemed
the fact
had
that
probable
by depletion
to
It
still
was
an
experiment.
in the other
as
exudation
large
as
as
had
much
the previous
on
difference between
plants
on
a
in
the
to
the
rate
in
the
by changes
for
conductivity
have
of
exu-
amount
water
greatly decreased
the
distilled
on
in
changes
might
roots
and
water
of
one
be
the
of
addition
favourable effect.
the
others
factors
decrease of the
in
the
must
metabolic
would
roots
with
happened
same
that
involved.
activity
caused
concerned.
be
by
promoted
that
plants
be
It
has
the addition
(fig. 11). It therefore appeared plausible to
deficiency of sugar would be the cause of this decrease.
from
appears
secretion
same
the medium
that
suppose,
of
was
been shown that the exudation could be
of sugar
parallel
of salts in
been
a
the
water.
and
just
of substances
In
were
might
been conducted
in the former
ran
rate
appeared
a
that
as
periodic
Depletion
had
grown
results
distinct.
that had
accompanied
are
salts, indicates
up
the
typical
a
secretion
plants
just
distilled
that the
decapitation.
when
be
the vessels
to
The salt
12 a.m.,
of these three
on
plants
given off
after
cause
to
those
seen
tomato
roots.
day
and
the
however, consisted not of a Hoagland
Exudation, salt secretion and k showed
given off, but k
was
morning. This proved
387
a.m.
individual differences
sometimes less
however,
day
decreased and less salt
secondly
that had been
Corresponding
experiment
an
way; the medium
same
solution but of distilled
the
and
increase from
to
plant
a
although
were
recorded of
are
given off at
decrease afterwards. At 7
to
under normal conditions of illumination.
obtained with all such
was
336.
to
was
503
largest (table 13)
was
Indeed k
too.
PLANTS
TOMATO
table
13
increased when
exuding weakly,
(experiment
sucrose
even
that
24)
exudation
administered
was
to
though the addition of
a
and
salt
that
plant
sucrose
caused
increase in the osmotic value of the medium. This stimulation, how-
ever,
salt
solution
tation,
the
only temporary:
again, and less salt
of which
was
(experiment
tered
secretion and k also
the
two
strating
any
corresponds
The
just the
24 b).
leaves,
could
same as
that
influence
of
Went’s
the
experiments described
that had been in the
sugar
results
up
the
be observed
in
were
could
did
supply
on
put
after
a
days,
two
was
de-
on
decapiadminis-
exudation,
salt
decapitated right
be
not
was
over
no sucrose
plants
we
exudation
plant
a
immediately
when
these
(experiment 24c). Thus
with
hour
When
fluctuations
when the
so
one
sucrose
Periodic
occurred
lowest
solution
sucrose
M
0.02
containing
about
given off.
was
considerable exudation
a
course
over
after
was
creased
submerged
in
a
succeed in demon-
periodicity,
which
(1944).
to now
light by day
were
carried
and in darkness
out with
plants
during the night.
504
O.
In
later
We
day.
show
that
the
rhythm
4-6
fixed
contrast
early
an
in
that
they
first
dation
to
the
although
Next
after
day
begin
decapitation.
exudation
average
the
but that
somehow caused
of
ment
they
the
The
day
plants
take
to
was
to
time
could
as
light
at
not
proved
during
normal
a
be
not
exu-
observed,
day than by night.
they
might
phenomenon,
which the maxima
the
were
that is
15
decapitated
the results of Speidel,
off
at
8
a.m.,
during the first
24
good
a
maximal exudation
a
before
evening
cut
gradually
day,
next
;
at
decapitated
increase
that had been
confirm
changes
obvious. This
more
the time
When
to
they showed
plants
as
small
by decapitation or one of its afterinvestigate whether perhaps the mo-
place.
experiment 24 d)
13,
decapitation,
same
artificial
afternoon did the
not
are
usually
were
the exudation
(table
the
were
changes
now
necessary
experiment
after
in
decapitation might determine
however,
we
are
was
occurred.
in
stronger by
was
fluctuations
periodical
It
for
during
usually much smaller.
were
strikingly
Only
indicate that the
effects.
might be
green-house
decrease. A distinct maximum could
however,
day
plants
the exudation showed
particular
the
water
(1939)
weeks.
The diurnal fluctuations of these
In
for
development;
kept
the
also
plants
if it
except
ordinary
were
these
conductivity
of
been
during
Grossenbacher
to
stage
an
had
the dark
that
13)
secretion and
in
were
after
in
period of lighting,
at
plants
weeks;
5-6
for
night
the
said,
first
salt
(table
that
used,
were
kept
were
24d
morning. So
is
ANDEL
plants
they
experiment
influence of the
no
the
have
we
from
see
end of the
find
we
while
overnight,
maximal exudation,
a
by the
however
experiments
illuminated
VAN
M.
hours
precisely
at
hours
the
earlier.
So
Heimann and Grossen-
BAGHER.
We have
shows
already pointed
whether the
the
on
effect
fluctuations
periodic
same
uptake
at
various
transferred from
solutions
be
to
secretion.
salt
cannot
times
gain
must
a
the
uptake
in
calculated
be
of salts
and
changed again for
on
a
an
a
when salts
at
the
is
which
not
the tissue
very
accurate
For
hour
an
by
secretion
the
this
present
reason
we
before
after
the
was
The
the
was
in this
as
must
total
substitution of
a
solution
From those data
at
we
this
mannitol
had been
estimated
the
way
was
quantity
determined. However this
in
case
be obtained
uptake secretion
mannitol
data obtained
of
the
in the medium. These
time. When
the
amount
lacking salts from
determined the
the
the salt
plant
However, it proved
changes of the uptake
subtracting
same
depends
hour.
solution
are
rate
solution of mannitol. The
a
into the
Hoagland solution.
either.
any
questioned
by determining
the value that the total salt secretion would have had
at
at
be
may
variable, incorrect values
following way:
half
to
insight
time
given off immediately
solution
It
day. For this purpose
determined
determined
secretion.
the
investigated
after half
again
the tissue secretion is very
for
was
proper
unit of
24a).
for the part of the exudation that
of the
given off
be
that the tissue exudation
Hoagland solution
a
per
that is
quantity
values
to
This
given off
true
This
changed
were
difficult
holds
of salts.
out
(experiment
moment
method
are
given
THE
in
table
but
14.
the
The
(table
This
was
not
are
of the
composition
the sap
SALTS
ON
THE
EXUDATION
OF
They indicate that the uptake
changes
6).
OF
INFLUENCE
proved
sap
with
variable.
very
changes comparatively
secretion
changes,
of
amount
TABLE
of
that the osmotic
fact
than that of
more
nitrate,
given off
salt
but
of
consider
we must
secretion
salt
given
on
value
given off
phosphate
14
the
of
amount
amount of
time
also
change little during the day
to
the
The
Periodic changes
Experiment
505
PLANTS
very evident.
corresponds
not
TOMATO
off
salt
on a
uptake
a
mannitol
secretion
Hoagland
solution
solution
(tissue secretion)
25
9.15
0.68
9.50
10.25
0.71
11.55
0.65
12.30
13.05
0.54
14.25
0.52
15.00
15.35
0.41
16.40
0.35
17.15
25a
17.50
0.21
9.20
0.49
9.50
10.20
0.57
12.00
0.63
12.30
13.00
0.61
14.30
0.63
15.00
15.30
0.61
16.45
0.48
17.15
17.45
the
influence since
the
case
the
error
0.19
0.32
0.15
0.20
0.08
0.35
0.18
0.42
0.20
0.37
0.25
0.24
0.18
of determination
concentration of
The exudation of Sanchezia nobilis
longer
a
time. This has
10a): both quantity
changed
very
little
observed.
were
was
0.41
phosphate
was
might have
sometimes
small.
very
over
0.15
0.35
that in this
possibility
some
0.55
26.5
taneously
those
In
mm/30
from
observed
of sap
been
and
salts
of
In
24 hours.
over
proved
already
be much
to
seen
given
some
off per
cases
sec,
778
with
salt secretion and k
to
622.
These
tomato
were
23
plants
proved
to
mm/30
changes
(table
change
sec.
are
14).
to
regular
(experiment
unit
of time
greater fluctuations
experiment 24e (table 13) the greatest
the smallest
more
in table 6
rate
observed
K decreased simulmuch
Rate
smaller
of
than
exudation,
approximately
the
same
extent.
These
plants
were
grown
under the
same
conditions
as
the
tomato
506
M.
O.
plants,
that is in
the
VAN ANDEL
lighted green-house.
According
fluctuations in the exudation of Sanchezia
can
in
This
the
here;
for the
the
the
though
Moreover
concerned.
So
at
when
in
changes
have
we
external
some
not
time
a
surroundings.
of the
temperature
was
temperature
afternoon,
again.
of the
temperature
even
condition
air
temperature
and
required
of these
in
fact
When
that
of
transport
caused
xylem
should
and
the
outer
exudation:
sap
will
investi-
would
periodicity
conditions.
If this
the
is
of
two
of salts
in that
water
internal
factors
the
vessels
into
the
way
active
of
values of the
The latter factor,
roots.
working
an
transport
true
secretion
and
water
osmotic
an
the
from
consist
between the osmotic
solution.
the transport of
in
extensive
naturally,
concentration
the vessels.
first
discuss
results
these
factors
and afterwards
as
process
in
separately
will
we
try
the
of
light
give
to
a
our
picture
of
whole.
a
secretion
In
two
section
parts:
same
1
we
time the additional
from the
of water caused
by salts taken up from
transport
given off to the vessels. These conclusions were drawn
following facts: the
dation indicated
the
argued that the exudation might consist of
by salts given off from the tissue and at the
have
that caused
the medium and
that less
course
salt
is
secretion
continue
osmotic
value
of
the
resulting from salt uptake
proved
to
only by
be
the
so
from
salt
in
change
the
remembered
process
the
is
was
concerned,
the transport
concerned with
so
that
that
the
concerned
only
the
the
only
expression
with
the
tissue
the
exudation
of
transport
water
being influenced
solution.
when
no
secretion
tissue secretion
transfer
and
by changes in
the
as
of salts
outer
case
exu-
long time. This
a
far
so
of
immediately
that exudation
for
rate
while
rate
the vessels
to
nevertheless
slower
concentration of the
the medium,
whole
It
a
medium,
dependent,
We will first be
into
but
at
off
of the exudation and secretion could be influenced
part
the
may
of the
given
uptake of salts is inhibited,
salt
be
and
conductivity of the
water
were
between
external
by
2° C
relation
a
more
decreasing
i
only
started
we
process
vessels
the
exudation
Salt
the
to
and
experimental
the
investigation
exudation
control
sap
influences
We
the
salts
A
influenced
by the resulting difference
the
of the
this
planning
of
case
little;
a
the end of
at
decide whether the
to
the
GENERAL DISCUSSION
IV.
hypothesis
be
but
already
was
finding
periodicity.
be
cannot
in
be
not
diurnal
changes
to
might change
noon,
exudation
gation would, however,
plants
at
the
succeeded
not
could
room
maximum
a
Heyl
to
be attributed
of salts
salt
is
is taken
is
used
from
up
It
will
for
the
active.
the
tissue
vessels.
known
that salts
can
be
carried from
the
roots
to
the
shoot
THE
when
INFLUENCE
plants
are
creased in such
free
ions
and
chloride would be
must
in
that
1945).
of
distilled
Little
We
the
known
be
to
for
off from the vacuole. It is
given
the
to
calcium
plants
pea
in
the
with
that the
rate
possible
(1953) concluded
from the
would leak
when the medium consisted
shoot,
which salts
given off from the
are
difficulty
some
at
these
which
generally
are
(Hoagland
salts
1948).
It
will
given off
are
magnitude of the tissue secretion.
found
decrease in
a
exflux
the
of salts
from
the
when
tissue
of the medium was enhanced. The reason
pressure
relation between the osmotic value of the medium and the
a
which salts
at
off from
given
are
Lundegardh
(1945)
given off by
cell, its osmotic
the
mined
a
This
this
to
that
that the
its
smaller
pressure
enhanced. This
solution is
remain
regulation
as
a
the
of exudation but
quantity,
a
salt
are
by
time b-fore
the
supposed
solution.
very
tissue,
no
of
sap
osmotic
rapid.
a
as
value
in
view
experiments
in
as
our
when
own,
no
salts
decreases, while
of the
medium is
This indicates that if
must
and
be sucked
a
salt
in from
It
seems
however
the whole
an
as
secretion
more
water
tissue.
the
unchanged.
was
to
would
suppose
It has been shown
exudation
that it
sap.
smaller
a
epithelium
plausible
more
took
a
was
quickly
much
longer
fully inhibited. This could
regions
central
decrease in
given off in
was
vascular
root
that
had been
indication that
the
a
the concentration of the
the
only
with inhibitors
the tissue
as
supposing
our
Lundegardh did find
considerable amount, but
well
by
is
seek
to
be understood
even
exuded
more water
change
that
given off from
considered
roots
is
solution.
outer
experiments
decreased
be
regulated
amount
the
as
well
as
but that the relation between salt and
that salts
the
1951)
solution
salt
differences between
(1950,
deter-
plausible
been demonstrated in the
he concluded that the solution
Lundegardh
exude
seems
is
theosmotic
result of the concentration difference between this salt
the
reason
It
are
is exuded
cells
turn on
of this
quantity
less.
water
the
in its
depends
osmotically
the
and
For this
is
increases
solution
rate
some
has
Van Nie
given off from
the medium
from
water
is
that
so
obvious.
very
when salts
along these lines, that is
given off from the tissue. It must
movement
value
of
which
in the medium. The
osmotic
not
problem
there
water
cells, is
decreases,
A
Helder and
present
are
value
turgor
that of Lundegardh. It
of Arise,
the
following explanation:
exudation
medium.
when the
salt solution is
however,
the
gave
turgor pressure,
the
of
out
answer
that
time.
their
by
pressed
the
a
same
pressure
in
few
osmotic
rate
at
de-
contain
to
improbable that ions like nitrate
large quantities in a bound state, we
in
of the way
given off
probable
control
Prevot,
much
seems
present
transported
is
Salts, that have been accumulated in the vacuole
supposed
seems
of the tissue
content
507
PLANTS
Harrison and
(Steward,
salt
TOMATO
water.
is
vacuole.
it
of intact
roots
vacuole and be
OF
the situation is different. Hylmo
phosphate
the
As
EXUDATION
plasm is usually supposed
that ions will be
assume
that with
The
case.
THE
water
1948). The
a
(Arise
SALTS ON
distilled
on
Hoagland
1942;
OF
parts
towards the
are
of
salt secretion. The fact that the tissue secretion is
periphery
for
of
the
importance
fully inhibited later
508
O.
than
the
since
evidence,
There
subject
few
are
the tissue
if this
known
is
also
might
however,
that
be
various
inhibitors
not
a
could be
new
be
that salts
discussed
after
transported
Hoagland
one.
Broyer
permeate
can
in
his
taken
this
From
migrate
cells
of
in
leaves
the
through
(1948,
also
1952)
of
cytoplasm
Vallisneria
spiralis
the
This
vacuole.
conclusion
roots.
might
the
first
affected
that
be
accumu-
KCN,
by
in
could
ions
been
having
not
was
process
sap
the
bromide
chloride
of
con-
circumventing
the
to
came
possi-
uptake
expressed from
circumstances
through the plasm without
transported
lated
vessels
Arisz
such
outer
its
out
the
on
the
supposition
that the exudation
roots,
that in
concluded
the
to
vacuole.
the
he
This
already pointed
investigation
radioactive bromide than the sap
salt
by high
from
up
the vessels.
to
has
(1940)
this
on
is taken up from
below.
tained
more
transferred from
are
when salt
having been
directly
found
(1950)
case
bromide
nor
DNP.
by
We
the
found that the
vessels
salts
replaced by
was
exudation
increased within
—
whether this
a
and
—
few
a
solution of KC1
the
exudation.
of the
sap,
attributed
be
might
a
that
found,
more
the
transfer
KNO
of
squash
As
would
take
half
plants
the
cause
he
hour. In his
to
stated
cortical
that
cells.
experiments
the
dye
was
Afterwards
this
fact
in the
the
would indicate
roots.
indicates
out
the
way
The fact that the
that the
tissue
after
from
it
the
had
to
the vessels in the
are
be
of
dispute.
at
first
generally
takes
rather
been
added
the
to
cut
to
the
surface
their calculation,
to
the medium into the
in
changes
the
only
salt
after
a
concen-
quarter
uptake and transport of neutral red
and
the
it
vacuoles
could
which
ions
are
of the
found
be
hour. In Lundegardh’s
an
was
transported
in
opinion
through
first accumulated in the vacuoles
was
concerned
indications that
same
from
must
due
It has
roots
roots
accumulated in
secretion
in section 3 b that there
ported
in
dye
beyond
root.
the
across
disappeared,
the walls of the vessels within half
this
up
increase in
secretion
of exudation is
according
bring salt from
on
first
it
questioned
composition
increased
tration of the medium became evident in the sap
an
be
into
lacking
found bromide in the exudation
found that
(1949)
may
apparent
10 minutes
required
Lundegardh
vessels.
salts
of salts
approximately
minutes would be
.
an
an
put
rate
(1938)
hour
an
transport
It
s
secretion
solution
a
enough ions taken
or
to
the
of
time. Crafts and Broyer
medium.
20
in
that the increase
if
determinations of the
however,
possible
to
chloride
of
the salt
the increase of the exudation
cases
secretion
not
or
larger secretion of ions already present
been
sap
is
a
from
appeared
that in similar
to
It
nitrate.
It
thus
minutes,
that within that time
means
the medium have reached the vessels
of
It
way.
sufficient
as
The theories that have been advanced
radioactive
to
this
considered
the way in which salts
on
They will
supposed
solution,
It
in
explained
be
can
concerned with the
mostly
medium.
bility.
data
the vessels.
to
are
We
is
it
VAN ANDEL
rapidly.
very
the
secretion
uptake
questionable,
seems
M.
way.
not
here.
all
We
ions
It follows from this
pointed
are
trans-
that it is
not
THE
possible
stance
the
at
the
in
given
off
also
might
It
is
This is,
be
is
when
directly
is
solution is
the tissue
be
may
since
the
off
other salts
Administering
salts
were
bility
that
proved
the
of the
the
to
take
the
some
act
can
should
transport
on
rate
at
did
contain
not
which salts
Lundegardh
the
to
a
c.f.
to
the
exudation
in
the
the
effect
It
be
1951)
and
of the
vessels),
and
(the cell
bridge
symplast.
case
a
"up
that
in
the
a
so
that anion
Robertson
(1950)
respiration
developed
The inhibition of salt secretion
supposition
of salts.
of ions
are
that the
However
depends
present
in
on
similar
to
of
the
is
theory
on
According
the other
along
at
one
(vacuole
importance. Weeks
be consistent with the
transport
just mentioned transport
the anion
respiration, which operates only
medium.
In
our
the
secretion.
concerned Vith the
theory
outer
case
idea.
by KCN would
cytochromesystem
according
the
would be
a
at
into
remains
this
vessels.
It
was
promotion
therefore
advanced
to
reduction
surface),
possi-
of sugar
the tissue controls the salt
Burstrom
when
the
affected when the
not
might
the vacuole
at
of salts
only
be taken
must
In that
expected.
was
coincide
transport
mentioned
salts
sucrose
it
involved,
his idea anions should be
transported across the cytoplasm
bridge of cytochromesystems. Oxidation should take
place
end
or
salts
but
a
secretion
be
must
the
We
of
uptake
be
fact
vessels.
the exudation.
salts,
The
value of
16) indicates that
processes
in
time before
given off by
(1950,
of
transport
are
be
the
to
remarkable that the tissue exudation
solution
actually
decreases
decrease under the
to
that these
solution.
rather
is
unimportant.
shown
promote
outer
this
enhanced.
experiment
were
roots
proved
is
time
the cells.
secretion
when the osmotic
could
so
that
the secretion
might indicate that
the tissue before it
of
do
taken up.
same
The decrease of the salt
suggests
they
in
to
This
and
is
the
at
given off from
medium
vessels
2
chloride
can
the tissue
quantitatively
promotes
sugar
however,
the
be active.
This
sugar
present
perceptible.
of
the
(table
are
through the symplast
ion
indication
only
tissue secretion
Where
partially.
same
indirect
to
solution
outer
has been shown
It
question.
of the sap that nitrate and chloride
decrease in
a
influence of inhibitors.
least
has,
place
The tissue secretion
salts from the
the vessels and also
to
must
and
It
take
can
It may therefore
same.
time, while only
that the
pressure
great that
this
content
same
enhanced
uptake
sub-
from the medium salts
uptake
supply of
decide
more
given
secretion
so
Both
a
osmotic
salt
certain
a
vessels.
xylem
the tissue
from the medium.
have demonstrated that
the
that less
salt
the
found the
of salt
the
to
proof
no
however
We
true.
the
at
however,
transported
There
transport of
to
go
(1948)
comes
difficult
given off
509
PLANTS
and
given off from the vacuole at the same
possible, that in such circumstances all nitrate
by determinations of the salt
be
must
case
only begin when
off.
TOMATO
in
be
the vessels
to
would then
can
the
on
OF
ions.
up
the
accumulated
It
cut
of all
taken
whether
time.
was
salt
EXUDATION
data
uncritically
time. Hoagland
same
be
SALTS ON THE
been shown that accumulation in
asked
can
OF
transport
the
of
however,
be
apply
to
to
Part
INFLUENCE
experiments
a
notable
if salts
amount
510
O. M.
of salt
in
proved
the
have
pointed
inhibitors
be
to
Lundegardh’s
phosphate
(c.f.
the
on
to
the
remains
that
differences
the
thinks
(1952)
in
that
connection
that
however,
the
on
if this
the
ions
with
in
explain
can
the
hand,
one
be
may
metabolism
take
might
transport
when the salts have entered the
cytochromesystem,
questionable
for
and chloride
perhaps
supposes,
probable
more
account
(nitrate
Helder
carrier,
He
seems
were
lacking
by KCN. We
affected
the exudation.
on
cannot
other).
certain
a
Steinbach).
place by
It
theory
of the various ions
also
was
it
that
indirectly
more
vessels when salts
the
to
transport
already
out
act
transport
bound
transported
solution. This
outer
VAN ANDEL
plasm.
differences observed
the
here.
Phosphate
much
vessels.
This
rapidly
be bound
is
the
points
to
bound
state.
We
the
a
that
of salt
process
that
within
of salts
leakage
Lundegardh
off,
so
that
This
is
opinion
cells
be
and
cells
by
founded
at
cell
a
to
his
is
process
kind
of
same
time
given
off
the
akin
is
to
explain
salt
takes up
process,
the
concerned:
the
vessels would
Helder
salt
strating
cells
affected
mass
the
the
Nie
glands
of the tissue.
not
(1948,
of salts
caused
transport
compare
this
KCN,
by
in
neither
but
vessels.
flow from
while
case.
with
we
do
inhibited
the
know
Considering
medium
to
is
might
meant
the
at
are
Biddulph
1951) calls
“a process
a
secretion
in that
process
secretion
a
the
secretion
succeeded
in the
by DNP, but
into
direction. Arisz,
with
(1953)
process
salts
of
of
in demon-
vacuole of the leaf
the
uptake from the
the
protoplasm was
implies that different active processes
into
uptake
not
this
This
rapidly
substances,
organic
transport through
This
cells.
occur
By
which
c.f.
by
that the accumulation of chloride
by
into the vessels
of salts
Arisz
it
that
controlled
the
can
(1948) also thinks that
of Statice.
was
it
but
gives
thinks
(1950). Accord-
from
interfaces,
and
the exflux
deficiency
cause
Van
salt
concerned
vacuole,
into
salt
of Vallisneria
medium
are
and
by the
cellular
Hoagland
secretion”. Alberda
and
roots,
(1952)
of Lundegardh
hypothesis
metabolism,
why only salts,
that controls
of the
Arnold
occur.
passively
permeability
the
at
the vessels.
to
process
with
salt
high
exchange
exuded
are
connected
not
because of the
a
salts
opinion
a
thinks
(1947)
the surface
active
an
in
concerning
Broyer
Wiersum
should
on
will
even
transported
(1949). Lundegardh himself revoked this supposition
ing
(1952)
so
the
phosphate
Arisz
through the symplast,
transport
no
reaches
the result of lack of oxygen
as
that each
believing
there is
extent
greater
up
that
might
exudation.
vessels
a
taken
protoplasm.
than the
the
to
given off from the
are
glycolysis.
been
phosphate
and
transport
to
by the fact that it takes
supposition
the
the endodermis have
like
salts
has
the
in
chemically
lower accumulation level
so
that
with
consistent
the tissue
indicated
mentioned the view of Crafts
have
that cells
is
as
phosphate
possibility
in
retained
chloride,
before
time
be
to
seems
than nitrate and
the
if the
the
shoot
plasm
same
and
holds
transpiration
through
cell
secretion
true
stream
walls
into
the
for the secretion
as
and
a
passive
cytoplasm
INFLUENCE
THE
Hylmo
OF
he supposes that with the
vessel elements in the
cells
as
time when
some
This
the
xylem
the
tissue.
root
flow
of
transverse
our
sudden
large decrease
of ions
O
—
m
of
It
stances.
water
the
to
we
the
be
should
)
the
causes
the
into
passive
a
salts
the
to
that it
vessels
seems
along
Whether there is
vessels
xylem
a
explain the
to
are
secretion
a
cannot
we
or
an
decide.
yet
reflects
in the Introduction that k
value
both the size
could
value
of k
of the
change in
to
conditions,
sometimes
diminished
a
them.
cause
of k
held
to
water
Jost
Kohnlein
conclusion
a
than
water
appeared
to
not
a
while
a
later.
in the
change
a
under
the
influence
inhibitors
only
of k.
decrease
accompanied
reduced
by
a
secretion. The
salt
of
zones
results
way.
roots
parts,
were
of Vicia
any
Faba
the
confirmed
by
quantity of
supposed valves
more
water
but
improbably
were
tension
in
the
basal
the
same
parts
vessels
in-
(1953). Lunde-
sucked
be
from
high.
permeable
more
the suction
to
to
from
demonstrated
of the
Brouwer
water
to
resulting
came
of
through
appeared
1939)
resistance
suction
proportionately
more
(1937,
resistance
sucked
the vessels
otherwise be
Brewig
if the
more
At first he
much
was
because it
tension in
but
the
that
water
more
supposition
certain pressure, but later
contain air
and
criticizing Jost’s methods,
different
found that the
would let pass
discussed
reversible,
possibility
as
of the shoot would
increase
extent.
the
decrease
made this
decrease
(1945)
be
nearly always
by
as
mentioned
might
the basal
These
did
at
in
well
as
usually
be
to
will
the result of
as
might happen
This
cases.
which
irreversible
an
that the suction
(1930)
apical
the
greater
con-
circum-
system and its resistance
root
several
case
were
appeared
(1916)
transpiration
gardh
water
several
on
true.
authors
experiments
creased.
depends
in the formula
of the
measure
pH of the medium,
changes
exudation
also
Several
roots
the
or
The
A decrease
reverse
a
transport.
inhibitors.
not
functions
because in such circumstances
considered
The
roots.
constant
osmotic
open
of
medium,
Changes of k could also be observed
roots
the other
secretion
no
conclude
only
can
expected.
into
has been shown
under
to
as
way
tonoplast,
ions, which
up
leakage
a
already been stated
ductivity
that
there is
Thus
ruptured.
conductivity
b=k{O b
the
same
the
function
to
been
increase of the salt secretion when salts
or
added
or
after-effect would be
It has
his
the
has
gradient, since it would then be difficult
accumulation
K
is
that there
removed from
the
in
continue
wall
plasm, probably
The
experiments
own
concentration
of
surfaces
upper
xylem elements take
the
probable
Water
511
PLANTS
water.
From
some
OF TOMATO
development of the interconnecting
plasm
membrane.
semipermeable
xylem but
to
EXUDATION
xylem cell would accumulate ions
of the
a
less
THE
ON
gives the following working hypothesis of the exudation
(1953)
process:
for
SALTS
through wheat
force but
present
to
a
which would
(1950) he stated that
the
cortex
when the intercellular channels did
were
filled with
water.
It
would take
512
M.
O.
time before all
some
could
water
These
increase
panied
by
In
but
tension in
owing
our
.
increased
was
the
by
The fact
that
if salts
and
which
could
two are
be
We
conductivity.
have,
when there is
of the
suction
(Brewig,
conductivity
water
nevertheless increased. When k
effect
of inhibitors
indicates
that
in
tension
apparent
that
to
to
by
external
as
for
so,
the vessels
and
take I
to
parallel might
run
This would be
by internal
however,
the
phenomenon
of salt secretion and k
interdependent.
possible
changed
suction
of
spite
different
a
the
above.
one
secretion
process
of the
a measure
In
water
conditions,
the result
as
in-
instance,
conditions.
that under certain
seen
reduction of the salt
a
an
accom-
The suction
quoted
be
not
mean
always
value of the
influenced
would
which
were
tension in the vessels.
given off together
were
flow
water
of exudation and
examining
authors
water
it
case
to
of the roots,
tension.
This
changes
dicate that these
rate
rise
the
have been
we
however,
decreased when the osmotic
no
or
unaltered.
discussed
resistance
even
periodicity
similarity
viz.
the
lowered, while k
was
to
instant,
easily.
experiments
there
from that
gone;
conductivity
the vessels
remained
that
in
water
ANDEL
increase of the suction
an
Brouwer)
medium
pass
the
would be
more
decreases
in
air
VAN
of
a
decrease in the salt concentration of the medium k remains unaltered,
or
increases
even
(when
water). Conversely
the medium
pH of
From this
sarily
be
we
in
sought
in
important
the
and
to
The
Broyer
pressure
of the
Broyer
idea
with
the
Brouwer’s
experiments,
cumstances
the
It
be
may
Arisz,
experiments
salts
when
Helder
present
experiments
solution is
it.
The
taneous
and
in the
given
Hoagland
in section
increase of k
in
changes
been
is
1,
that k
in the former
osmotic
simultaneous
of
that
this
It
a
follow
we
would
in
cir-
such
an
be
tissue.
the
increase.
movement
by
distilled
specific
appears
in
of
ours.
water
water.
effect
of the
however from the
change if a Hoagland
lacking salts but isotonic with
does not
another solution
the
parallel
of turgor pressure in
the
replaced
solution.
processes
much greater than
to
salt
in the osmotic
that if
pressure
section
both
a
secretion
indicate
that the resistance
salts
of
to
(Hoagland
should rather show
water
that the
of
there is
seen
salt
turgor
affect
case
is
that both
In
cells).
changes
have
the
Van Nie considered
replaced by
decrease
the
have
must
solution
a
for
however,
We mentioned above
decreases
of
of
however, would
conductivity
observed,
Brouwer’s
clear. We
decrease
last
from
resulting
less
decrease
a
The
1951).
or
deficiency
oxygen
neces-
change
metabolic
by acting
protoplasm, for which
salt secretion
medium is
Lundegardh’s
connected
of the
the
might
on
concerned with
1942;
of k and
that inhibitors
not
are
of their simultaneous
transport through
the
considerably.
both
process that influences
as
distilled
by
by lowering
changing
conductivity
state
phenomenon
changes
diminish k
to
salt secretion
cause
a
(such
water
the
the
concluded
already
and
possible
conclude that the salt secretion and k
change of
a
Hoagland solution is replaced
without
common
have
we
secretion
in
can
a
appears
interdependent.
possess
6
it
case
value
must
of
the
result from
medium.
the simul-
We
did
not
THE
succeed
in
authors
have
INFLUENCE
demonstrating
found
and
the
on
OF TOMATO
effect
specific
any
influence
any
EXUDATION
Hayward
1941;
(Rosene
not
THE
OF SALTS ON
of
513
PLANTS
ions
k.
on
Spurr
1943;
uptake
of
Other
Long
1943)
by
water
roots
either.
As
the
to
observe
points
that
the
the
to
plasm
decide
however,
We
influence
in the
changes
concerned
a
question of which
that
have
the vessels
to
the
on
we
may
conductivity
water
whether
the
only
the
other
of the
protoplasm
cells
of the
roots
endodermis is
well.
as
of the exudation
given the following conception
process:
solution of salts flows from the root cells into the vessels. This solution
attracts
water
from
up
in
osmotic
an
an
of the osmotic
Nie
stated
pected
the
water
We
(table
value
accurate
the
that
will be
sap
Finally
III
as
section
we
parts.
a
of
called
It is
Our
In both
solution.
secrete
salt
a
salt
1
it
be
be
might be
it
during
in mind
kept
from
starting
the
given off
are
If the latter is
zone.
will
account
on
the osmotic
in the vessels
must
in
sucked
water
be
rather
seems
possibility
derived
water
It
sup-
to
the
larger,
afterwards.
and
salts
were
have demonstrated that the osmotic
we
be
higher
than
might indicate
we
that
should expect
water
from
the
taken up from
is
It
as
a
roots
is
we
into
where
difficulty
cases
is
the
vessels.
that
we
out
instance
We have
have
to
must
happen
difficult, that
explain
that salts
two
pointed
water
con-
might be given
that leaves of salt
already
simultaneous transport of salt and
tissue
This
osmoregulation is
pointed
known for
solution.
rather improbable.
seems
surrounding cells secrete salt
that the
solution
of the
zones
facts.
bability
more
this
for
might
errors
important
in which salts
absorbing
explanation would be
in older
as
ex-
repeatedly
explanations
determining
the sap
place
was
roots
for
aside
from
up
water
may also
concentrated
flicting
also
We
).
during the upward transport. This
sap
then in the
off
m
Van
should be
together.
chapter
Another
a
would be
used
was
the second
of the
exudation observed. This
or
O
before.
deviation would be observed if
value of the sap
the
—
experimental
possibility
errors
mentioned
diluted
similar
a
off
given
In
just
(0 6
than
mentioned various
this
taken
transport.
zone
k
=
place
Setting
sap.
are
coincides with the
vessels
Nie
first
method which
the formula
In
the
experimental
position that the
the
Van
In
that salts
upward
the formula b
Helder and
Arisz,
lower
usually
were
2).
and
of the exudation
supposed
this idea concerned with the determinations
have discussed
that
improbable
to
of the exudation sap.
strength of
same
taken
results
transport.
these values
phenomenon.
involved.
osmotically. In addition salt
given off to the vessels. This also
be
can
values
Helder
Arisz,
of the
the medium
objection
that
the
on
found
this
from
the medium
There is
is
moves
inhibitors
being involved. This is confirmed by the fact
pH of the medium can also affect k. We cannot,
that of
or
water
way
of
to
plants
the pro-
by the process
exudation.
known that in excised roots
most
salts
are
accumulated in the
514
M.
O.
apical
and
(Prevot
zone
Harrison
1942).
the
apical
zone,
This difference
in
but
was
cases
in
more
The
of Brewig
resistance
to
which
Nie
resistance.
zone, but
it
as
is
is
a
pieces
root
basal
lower
The upper
part.
concentrated.
of the
of the
possible
seems
tissue
This
and
also
plants
that the
not
the
to
impossible
might
difficult
To
it will
that had
have
that little
perform
a
more
salt
of
the
is
30
mm
upper
proved
was
is
may
more
between
found
a
In
that it
experiments
used.
were
Lundegardh’s
direct
transport
experiments
our
under
parts
hampered
observe
plants
young
a
give off
to
sap
and
and
such
conditions
high salt condition. It
is
accumulation into the vacuole
for
with
direct
is
plants
thorough understanding
various
zone,
that the older
We
available
to
an
movement
grown
salt
place
apical
larger
give off salt
roots
was
plants.
rather
roots
of low
be necessary in the first
zation
very
salt
a
in
zone
the
in
a
Lundegardh’s
(1950)
experiments
any
water
root.
been
been in
The exudation
to
gain
so
as
Helder
the
approximately
contrasts
Broyer
that with low salt
prevail,
the vessels.
the
only with high
used
must
chiefly
covers
of the
the
probable
of the smallest
zone
the exudation
of the
of the
own.
our
the
if
zone.
that
Arisz,
know
supposition
conditions of
some
vessels
were
roots
the
As
part.
divided into
and
our
predominated,
explain
experiments
of salts
with
greatest
apical
investigating the exudation
of
was
the
It is
zones.
not
part of the basal piece
higher resistance
in
parts
(1950)
give off salts, while
that
this
do
with
zone
The latter
agrees
secretion
might
tip
a
the other parts
This
also
roots
because
the
mm.
nitrate than
more
Lundegardh
distinguished
piece of 50
tip
may be localized
that the older
latter.
the
demonstrated
that the tissue secretion
possible
accumulated before.
of
in
we
off coincides
probable
seems
out,
given
uptake secretion
The
it
pointed
that
in the
vessels
Brouwer
mainly localized
already
salt
most
concluded
the
smallest in the
transport is
water
that the exudation is
and Van
and
than in
the accumulation in the basal
both
experiments
the
of intact
roots
accumulated in
was
case
and
compared
in the
salt
most
From
this
cases.
they
quantity of salt would be given off to
parts
and
the first
than that in
greater
Harrison
roots
Prevot
Steward,
and
barley
both
much
1936;
Prevot
excised
that in
They found
plants.
ANDEL
Steward
Steward,
accumulation of salt in
VAN
so
to
transport
weak
that
it
is
them.
of the exudation
collect
more
data
on
process
the locali-
concerned.
processes
Periodicity
The
fluctuations
periodic
accompanied
by changes
conductivity.
Various
bility
(Skoog,
1938).
The
maximum
conditions
by
by day
and
cycles
and
rate
amount
had
of exudation
of salt
already
changes
Broyer
and
a
in
the
in
1938;
transpiration
minimum
water
given off
suggested
Grossenbacher
during
(Montermoso and Davis 1942)
assuming
Skoog,
authors
Broyer
periodic
of the
in the
the
of
be
proved
to
and the
water
the
latter
possi-
Grossenbacher
plants
showing
night under
a
constant
might also be explained
conductivity.
The
Grossenbacher showed that
investigations
more
factors
of
must
THE
be
INFLUENCE
involved.
THE
found
little
a
both
experiments
our
SALTS ON
also
They
maximum occurred
in
OF
EXUDATION
OF
fluctuations
later
than
occurred
in
If
changes
in
to
when
be
the
in
changes
to
the
turgor
at
secretion
value
and
medium is
which
rate
This
wilted Helianthus
varies
This is
interesting
author
determined
plants,
that is
the
the
rate
would
of
magnitude
with
Hagan’s
exudation
negative
which
at
that
Above
be related
might
the
to
be
simul-
water,
salt solution
a
connection
in
a
changed.
changes
according
for
would
of
case
conductivity
latter
it
concerned,
are
turgor pressure of the tissue:
a
least shows
at
with another
of the
that the
possibility
pressure.
(1949).
paper
only
phenomenon
osmotic
the
expressed
secretion
this
of tissue
the
discussed
we
tissue
connect
change
taneous
occurs
the
The
while
a
periodic
however, less obvious for the uptake exudation.
fluctuation. This was,
attractive
secretion.
exudation,
time.
same
We have ascertained that the tissue secretion
515
PLANTS
salt
of the
that
the
at
TOMATO
water
of
sucked
was
in
through the stump. The negative exudation proved to be maximal
during the night and minimal by day. In the latter case positive exudation
might
even
taken
The
up.
but
medium,
These
responsible.
express
salt
solution
Running
mena
ations
in
Changes
on
the
According
the
in
by
enzyme
that
plants
of
changes
activity
the
a
is
certain
involved,
sensitive
Speidel
a
in
the
slower
root
water
so
cells
or
of the
enzymes
which
These
fluctuations
concerned.
would exercise
concerned
affected
by
influence
found with several
(1951)
assumes
change
by fluctu-
with
that
the
an
synthesis
endogenous
illumination
during
period.
tried
(1939)
be
can
caused
of the enzymes
Running
pheno-
tissue could
carrot
respiration
explain
to
the
by assuming changes in the production
periodicity
of
of exudation also
respirable substrate,
eventu-
ally
caused
and
Grossenbacher, however, found no relation between changes
by
exudation
and
exudation
has
If both
a
activity
to
changes
in
the
not
secretion
found
the
changes
much
processes
during
activity
Speidel’s
respiration.
fluctuating turgor pressure
beside
a
Enderle
pressure.
would be
activity
on.
periodicity
turgor
substrate.
respirable
in the
and
activity
of
of cellulose showed such fluctuations. He
rhythm
whether
various
of
pressure
of the
intensity
that
changes
Running this
to
production
from
the
at
show that the
investigate
not
present
although
in
hydration of the protoplasm
rate
any
demonstrated
accompanied
would result
the
were
could be
exuded.
was
periodically.
at
did
showed that the
turgor
(1951)
in
changes
was
a
plants
water
no
CO
or
2
when the
when
room,
if N
disappeared
Hagan
(1942)
were
happen
moist
experiments
liquid.
can
a
negative exudation continued,
Hagan considers
rate.
in
were
cycles
the
This could
occur.
soil, and also if they
of enzymes.
hypothesis
change periodically,
day,
but
It
investigation of Virgin (1951).
a
causes
in
of
maximal
the
hypothesis
of
might be that metabolic
there
those of Running and his collaborators.
of Helodea densa showed
the
of
Broyer
support.
is insufficient.
the
Skoog,
are
We
few
relevant
data,
attention
may call
Virgin found that the leaf cells
viscosity during the night, while
516
M.
O.
was
minimal
days.
Changes
viscosity
several
the time
that
by day. This rhythm could be maintained
in
the
in
changes
and
water
there is
However,
in
changes
viscosity
the
salt
of
plasm
from
Starting
the
transport of salt
to
For
continuously,
determined
at
tivity of
the
used.
were
certain
roots
caused
solution
medium had been
way it
partially from
the
directly
increase
in
demonstrated
It
sap.
takes
so
a
chloride in
exudation,
The
well
the
as
no
moreover
exflux
the
uptake
moreover
partially
coincide.
the
The
off
of the
changes caused
in this
was
the vessels
to
taken
been
must
have been
must
for
of
up
from
are
was
to
the vessels
chloride
that it
of
nitrate
increase
an
in
the
present.
were
—
the
taken
inhibited
chlorides
presence
caused
always
the
causes
of the exudation
and
The
come
trans-
exudation
phosphate
that of nitrate
tissue
and
the
composition
transport.
salt
outer
tissue
secretion
—
up from the medium
by inhibitors
like
as
—
potassium
sodium arsenate, sodium fluoride, iodo acetic
phenylurethane.
Their
This
common
water
part
indicates that both processes
the
be
might
conductivity
was
transport
of
also affected
by
substances.
Sugar proved
of the
of the
transport
cations
through the symplast. The
these
in
than
from the
—
the
of the
anions
the vessels of salt
secretion
on
nobilis.
value
only if nitrates
these
that
what
dinitrophenol,
acid and
salts
of
solution
outer
to
plants
tomato
course
given off
having
was
conduc-
the medium the latter process
method of
of salts
the transfer
cyanide,
time
matter
water
was
the
altered. From
but
exudation,
different
sap
the osmotic
of exudation,
which
to
after
in
present
more
the
with Sanchezia
while another
part
cells,
by determinations
much
the
cases
experiments
most
repeated
rate
extent
importance
appeared
suggests
or
the
The
included.
of
Lowering the salt concentration of the
the vessels
are
some
value
a
under
of exudation
rate
osmotic
in
were
simultaneously
root
of such
the result of
salt concentration of the medium
the
on
to
medium. If salts
an
Also
concluded that the salts
was
ported
the
decrease of the
a
depending
change
viscosity.
investigated
was
the
purpose
determined. In
studied first.
was
this
while
experiments
The influence of the
secretion
in
occurrence
that the exudation is
the salt secretion
instants.
was
Some
changes
about the
yet
SUMMARY
supposition
determined
of
result
a
as
in
permeability
explain the changes
to
cells.
root
the vessels
circumstances.
as
known
those
to
possible
seems
transport
nothing
parallel
ran
It
V.
various
over
of illumination could influence
periods
under certain circumstances.
of both
ANDEL
which maxima and minima occurred. Virgin demonstrated
at
the
VAN
to
promote
the exudation
only if salts
were
present
medium.
fact
that the
medium led
together
from
tissue secretion
to
the
the
depended
supposition,
tissue.
on
that salt
An osmoregulation
the osmotic
and
water
of the
are
value
given
movement
of
INFLUENCE
THE
water
must
influenced
sucked in
not
are
also
of
of
TOMATO
salt
suffer
to
minimum
This
water.
of the
exudation,
a
517
PLANTS
taken
the vessels.
to
from
up
seemed
process
experiments
independent
medium.
and
secretion
maximum
a
A relation
The
consists
acting
as
osmotic
the
agreement with the
of
value of the sap
determined
value
occurring
between the time
exudation
in some,
than
deviation
have
1948. The
of maize
uptake
would
been
be
of
different
and
hypothesis
most
low
too
cases
The
expected.
the
possible
discussed.
CITED
factors
influence of some external
plants
In
roots
however, the osmotic value of
LITERATURE
Alberda, Th.
this
to
found.
the
between the
agreement
according
certain
under
that the exudation
of water,
transport
during
be demonstrated.
observed
satisfactory
sometimes
higher
was
sap
of this
less
not
supposition
a
calculated
was
actually found,
was
and
salt
A
osmometer.
an
exudation
of
rate
transport
a
value
causes
in
were
of
the
in
changes
conditions
period of cultivation could
the
of
conductivity
water
periodic fluctuations,
during the night.
the
or
It
the medium
which maxima and minima occurred and certain conditions
the
a
with
value
shown
were
by day,
at
decide whether salts
to
transported
Rate
OF
by the solution given off from the tissue
the osmotic
roots
EXUDATION
take place afterwards, the osmotic value of the sap being
by that of the outer solution; that is to say that water is
possible
was
THE
OF SALTS ON
salt
conditions.
on
Rec.
growth
Trav.
and
phosphate
neerl.
hot.
41
:
541—601.
O.
Andel,
by
M.
Akad.
Wet. Ser.
O.
Andel,
M.
C
55
W.
van,
Determinations
of the
method
osmotic
of Baldes
and
value
of exudation
Johnson.
Proc.
Kon.
sap
Ned.
40—48.
:
H.
and
growth
on
sugar
1952.
van.
of the thermo-electric
means
Arisz
and
intake
salt
R.
J.
Helder.
maize.
by
Proc.
1950.
Kon.
Influence
of
Akad.
Ned.
light and
Wet.
53 :
159—71.
W. H.
Arisz,
and
48
their
H.
W.
leaves
1947.
W.
leaves
H.
Wet.
50
1948.
Uptake
secretion
W.
H.
and
a
theory
transport
II.
spiralis.
of Vallisneria
Vacuole
Arisz,
on
the
tissue.
absorption of salts by
Proc.
Ned.
Kon.
the
plant
Akad.
Wet.
Analysis
of chlorine
of the
tissue
by parenchymatic
of
transport
chlorine.
Proc.
of
Kon.
1233—45.
:
and
spiralis.
theory.
transport
III.
Proc.
1952. Transport
of
of chlorine
Discussion
Kon.
Ned.
Akad.
tissue
by parenchymatic
of the
and
transport
Wet.
organic compounds.
51
Ann.
:
the
of
uptake.
25—33.
Rev.
Plant
Physiol.
109—30.
:
Arisz,
W.
H.
1953.
chloride-ions
in
W.
1953.
Arisz,
H.
Influence
Bot.
Arisz,
in
to
parenchymatous
Uptake
of Vallisneria
Ned. Akad.
Arisz,
V.
in
420—46.
:
Arisz,
3
Contribution
1945.
transport
Neerl.
W.
H.,
tomato
Arnold,
E.
struction
on
;
R.
of
transport
J.
1952.
and
and
vacuole-secretion
and
of
Acta
transport by
the
and
plasmatic
Bot.
Neerl.
tentacles
1
:
transport
of Drosera
substances inhibiting enzymatic
of
506—15.
capensis.
processes.
Acta
74—108.
Helder
Ueber
Protoplasma
J.
uptake,
Vallisneria spiralis.
Absorption
the
plants. Jour.
A.
Wurzeln.
Baldes,
2
Active
leaves
its
A. F.
use.
and
exp.
den
41
:
R.
Nie.
van
Bot.
3
:
1951. Analysis
of the
exudation
process
257—97.
Funktionsmechanismus
der
Endodermiszellen der
189—211.
Johnson.
1939.
Biodynamica 2
The
(47)
;
thermo-electric osmometer;
1—11.
its
con-
518
O.
O.
Biddulph,
of
Plants.
Univ.
Blackman,
V.
Phytol. 20
Bonner,
The
of
H.
1950.
W.
D.
of isolated
L.
K.
root
pressure,
plants.
Mineral
Nutrition
and
pressure
exudation.
New
of
inhibitor
growth substance
action.
Thimann.
Bot.
37
Hasman.
1950.
action
:
Studies
and
growth
inhibition
concerned with
pyruvate
66-75.
1952. Weitere
Heteroauxins
the
on
of some inhibitors
bei der
Untersuchungen
iiber
den
Wirkungs-
Wasseraufnahme von Pflanzenparenchvm.
’
41
Protoplasma
selective
a
III. The
Jour.
M.
des
as
V.
parts.
Am.
und
A.
in
minerals
181—4.
:
and
mechanismus
Brewig,
of
: 261—75.
Press
Osmotic
Arsenate
plant
metabolism.
Brauner,
translocation
Wisconsin
1921.
Physiol. 25
Bonner,
VAN ANDEL
106—15.
;
J.
Plant
1951.
M.
302-26.
:
1937.
Permeabilitatsanderungen
der
die
Wurzelgewebe,
Sprosz
vom
beeinfluszt werden. Zeitschr.
Brewig,
Faba.
Bot.
31 :
481-540.
1939. Auslosung leichter
Wasserdurchlassigkeit
A.
Planta
R.
Brouwer,
ration
Ned.
ration
Waterabsorption by the
Analysis of the uptake
Ser.
C
56
1953. Waterabsorption by
II. Causal
relation
Proc.
T.
Broyer,
C.
F.
Broyer,
38
Akad.
The
E.
Planta
39
of
:
of
of
F.
H.
C.
B.
und
M.
Currier
Bot.
:
of
The
Am.
and
of
relations
inorganic
Am.
plants.
solute
Press
physiologischen
and
Tour.
:
37
der
accumulation
187-249.
:
der
Mechanismus
433-86.
und
Substanzproduktion
Photoperiodischen Reaktionsweise.
zur
und
G.
ion
C.
R.
Beitrag
Planta
d.
Bot.
13
250-68.
:
Mineral
absorption.
Migration
Jour.
Bot.
41
25
of salts
:
Stocking.
Nutrition
of
and
into
water
xylem
529-35.
1949.
Water in the
physiology
Mass.
Untersuchungen
Ein
osmotic
etiolierter
I.
und
39
zum
gravimetrischen Bestimmung
zur
Einfluss
der
pH
auf
die
Wasser-
65-82.
:
and vitalistic interpretations
of
exudation.
Am.
und
unde
Turgorschwankungen
1951. Das
LichtalsUrsacheperiodischer
Haferkeimlinge. Planta 39 : 309-37.
Goeze.
von
Weitere
1952.
1934.
A.
K.
A.
1938.
Untersuchungen
Planta 40
iiber
Guttations-
periodische
529-49.
:
Assimilationsverhalten, Chlorophyllgehalt
Getreideblattern
Stickstoffernahrung.
K.
an
570-88.
:
Friedrichsen.
G.
mit
Zeitschr.
Diurnal
besonderer
Bot.
fluctuation
27
in
:
Berlicksichtigung
und
der
257-340.
root
pressure.
Plant Phvsiol.
7
669-76.
Grossenbacher,
Am.
transpi-
resistance
Friedrichsen.
Grossenbacher,
:
of
1951. Tagesperiodische Wachstums-
Transpirationsgrosze
13
at various
tension,
251-60.
1938.
Guttation etiolierter Haferkeimlinge.
Kalium-
Kon.
: 663-74.
H. und I.
Gaszner,
transpi-
Proc.
129-36.
Zeitschr. Bot.
Comp. Waltham
-abgabe.
1943.
30
W.
H.
at various
Faba
of Wisconsin
den
Beziehung
Press
1952. Kritische
schwankungen
Engel,
in
Broyer.
Gewebekulturen. Planta
Engel,
Univ.
Uber
mechanism
Wisconsin
Chron.
Bot.
Enderle,
:
56
process
Pflanzen.
higher plants.
H.
S.,
The
T.
and
roots
A.
aufnahme
Jour.
C
Tagesperiodische Verlauf
Wasserpermeabilitat.
Eaton,
Vicia
suction
Mineralstoffwechsel. Fortschr.
1951.
S.
plants.
der
1951.
Univ.
Drawert,
Faba
determining it.
460-70.
H.
A.
Der
bei
Zellulosesynthese
H.
Burstrom,
of the
of
roots
the water
on
Plants.
Untersuchungen
1951.
der
Crafts,
factors
between
of the
of
Nutrition
1942.
speziell
Crafts,
the
Wet. Ser.
studies
nature
endogenen Tagesrhythmik
Plants.
of Vicia
roots
and
Further
1951.
Mineral
Burstrom,
Vicia
observations on the absorption and translocation of
using radio-active isotopes with plants. Plant Physiol. 25 : 367-76.
1951. Exudation
C.
E.
Bunning,
von
157-62.
roots.
Bunning,
Ned.
1950.
C.
:
T.
Broyer,
Kon.
solutes
inorganic
Wurzeln
106-15.
:
strengths.
uptake.
Bot.
I
Wet.
R.
Brouwer,
in
1935.
strengths.
Akad.
an
: 341^60.
29
Jour.
Guttenbero,
auf die
Bot.
H.
26
:
1939. Autonomic
von, und
A.
Wasserpermeabilitat
Guttenberg,
H.
von
cycle
of
of
rate
exudation
of
plants.
107-9.
und
G.
Beythien.
des
1951. Ueber
den
Protoplasmas. Planta
Meinl.
1952. Ueber
den
Einfluss
40
:
Einfluss
von
Wirkstoffe
36-69.
des
pH-Wertes
und
THE
auf die
der Temperatur
permeabilitat. Planta
R.
Hagan,
M.
detopped
106
:
Planta
M.
Acta
D.
1
:
der Wasser-
Veranderung
Spurr.
the water relations
of
1944. Effects
isosmotic
of water
entry
on
of nonexuding
441-54.
:
into
concentrations
corn
Bot.
roots.
of
Gaz.
periodischer Beleuchtung
auf die
Guttationsrhvthmik.
des
Blutungsverlaufes
und
Beleuchtung
von
377-90.
of the
of anion
process
of
uptake
maize
intact
plants.
361-434.
:
Der
R.
Einfluss
D.
Hoageand,
Comp.
8
R.
Aussenfaktoren
von
D.
R.
accumulation
accumulation
experiments
auf das
der
Bluten
Pflanzen.
by plant cells,
barley
on
with
special reference
Cold Spring
roots.
Harbour
Svmo.
181-94.
:
1948.
Waltham
Hoagland,
Salt
1940.
and
Biol.
Quant.
Lectures
the
on
inorganic
nutrition
of
plants. Chron.
Bot.
Mass.
and
by
T.
C.
Broyer.
with
roots
1936. General
of
description
of the
nature
experimental
process
methods.
Plant
of salt
Physiol.
471-507.
:
D.
Hoagland,
R. and
T.
W.
Hofmeister,
Saften
von
vations
C.
of
B.
L.
Jost,
1953.
1916.
The
2
uber
permeability
of
und
Ausflussgeschwindigkeit
138-44.
:
ions by
excised root
solutions deficient
in
II. Obser-
systems.
phosphorus, nitrogen
344-79.
:
and
Transpiration
Versuche
in
grown
Bot.
exp.
45
absorption
barley
potassium. Jour.
Hylmo,
Flora
of salt and
865-80.
:
Spannung,Ausflussmenge
Pflanzen.
1951.
roots
on
1942. Accumulation
25
Physiol.
1862. Ueber
lebender
E.
Humphries,
C. Broyer.
Gen.
plant cells. Jour.
die
ion
absorption.
Plant.
Physiol.
Wasserleitung in
der
Pflanze.
6
333-405.
:
Bot.
Zeitschr.
1-55.
1927. Untersuchungen
Kisser, J.
abgabe,
I.
Kohnlein,
E.
die
Planta
1930.
Bedeutung
Planta
10
Kramer,
P.
Bot.
;
25
1938.
J.
Kramer,
P.
J.
1941.
Am.
pressure.
Kramer,
P.
J.
Kramer,
P.
J.
the
1945.
water
Bot.
und
auf
die Wasser-
und
Wurzelmasse
die
Blatt-
562-77.
fiber
die
Hohe
die
Wurzeltatigkeit ffir
Root
resistance
1934.
M.
On
of
as
a
Soil
pressure
moisture
Bot.
Jour.
Plant
the
and
as
des
Wurzelwiderstandes und
Wasserversorgung
der
Pflanzen.
cause
of the
absorption lag.
Am.
Tour.
and
nutrients
effect
by
exudation.
Am.
limiting factor
of water
soil
Bot.
Jour.
for
of
of
roots
relationships.
electrolytes by
sap.
of salt
Bot.
by plants.
water
absorption
The
a
active
27
;
929-31.
absorption
and
28 : 446-51.
plant exudation
1943.
and
Sap
Absorption
1949.
chemistry
E.
Nahrsalze
Einfluss der
Spross-
110-13.
1940.
Long,
den
381-423.
:
J.
T.
:
Untersuchungen
P.
Laine,
3
aktiver
Kramer,
root
fiber
Wasseraufnahme, relativer
struktur.
Acta
bot.
additions
Rev.
Me
the
cut
Fenn.
the
to
approach-grafted
16
11
:
310-55.
Graw-Hill
roots
:
Book
plants
Co.
and
1-64.
substrate
tomato
of
on
the
plants.
intake
Am.
of
Tour.
30 : 594-601.
H.
Lundegardh,
Lundegardh,
roots.
Lundegardh,
Ann.
agric.
roots.
Ark.
1945.
f.
H.
influenced by
Bleeding
H.
and
und
sap
32
A
(12)
:
which
Sweden.
Bot.
1
The
(4)
:
16
Planta
and
31
Ark.
exudation
:
f.
of
184-91.
Bot.
31
A
(2):
inorganic ions bv
1-139.
1949. Growth, bleeding
1949.
Bluten.
movement.
Absorption, transport
Bot.
substances
coll.
f.
Anionenatmung
1943.
H.
Ark.
Lundegardh,
1940.
H.
LundegArdh,
the
519
PLANTS
20 : 294-353.
metabolism
:
24
Physiol.
substrates
1952. Analysis
1933.
Hoagland,
or
B.
in
diurnal cycles
Abhangigkeit
40
Neerl.
G.
Planta
1952.
J.
Bot.
Heyl, J.
in
W.
Einfluss
Planta
R.
Helder,
11
OF TOMATO
157-95.
M.
Blattzahl.
on
EXUDATION
431-42.
:
Plant
organic
1950.
:
38
Heimann,
to
THE
131-39.
Heimann,
8
and
ON
durch Heteroauxin bedingte
40
systems.
E.
and
inorganic
SALTS
Autonomic
1949.
root
H.
Hayward,
OF
INFLUENCE
interfere
and
with
salt
absorption
glycolysis
and
of wheat
aerobic
roots
as
respiration.
. 339-71.
effect
295-9.
of
indol
acetic
acid
on
the
bleeding
of wheat
520
O.
Lundegardh, H.
1950.
Plant.
Physiol.
3
LundegArdh, H.
169 :
Nature
L.
Machlis,
31
:
R.
and
P.
the
and
through
wheat
of
wheat
water
living
inhibitors
respiratory
some
A. R. Davis.
Helder
J.
of
excised
barley
and
roots.
roots.
intermediates
Am.
roots.
Jour.
Bot.
F.
H.
Am.
C.
1915.
1929.
R.
nutrients
in
H.
Rosene,
isolated
Sabinin,
Biol.
by
of
and
T.
B.
and
51
5
Stenlid, G.
on
Street,
and
H.
Plant
Handworterbuch
der
der
Filtrationswiderstandes
2
and
4
transport of inorganic
1-24.
:
1951.
on
Studies in the metabolism
salt
accumulation
and
salt
248-64.
:
in local
regions
root
of
pressure
the
of
and
attached
solution.
external
Am.
rate
of
in
exudation
excised
onion
roots.
as
an
osmotic
Inst.
apparatus. Bull.
Rech.
Botanik.
1952.
I The
The
effect
most usual
of
pH
on
relationship
the
activities
biological
between
and
pH
activity.
163-90.
and
A.
K.
and
A. Grossenbacher.
osmotic relations
Hampel.
1951.
1949.
F.
II The
189-200.
;
of the tomato.
1-136.
:
zur
in
exudation.
1938.
Am.
Effects
Jour.
des Blutens
Physiologic
C.,
P.
Jahrb.
Permeability.
The
in
Ueber das Bluten
1936.
Pflanze.
effect
young
Ann.
Bot.
of auxin
25
on
749-59.
:
bei hoheren
J.
E.
and
J.
to
Rev.
A. Harrison.
the
shoot.
der Wurzel im
Bot.
83
Plant
2,4-dinitrophenol
wheat
Physiol.
roots.
Prevot and
of transfer
wiss.
of
rubidiumbromide by barley plants.
lation
B
osmotic
system
2
Beevers.
einjahrigen
glucose uptake
Steward,
des
absorption
Ser.
cyanide
Suppl.
bases.
:
H. B.
Steinbach,
Pflanzen.
Physiol.
watertransport
Untersuchungen
und
einer
gange
19
Phytol.
Pflanzen.
: 67-112.
A.
Sperlich,
der
2,4-dinitrophenol
Res.
On the root
C. Broyer,
1939.
30
New
guttation
on
relative
system
172-4.
:
H.
rates, periodicity
Planta
root
509-34.
:
pressure.
ions
and D. C. Weeks.
the
Effect of
31
1925.
acids
of
Plant
of
effects
means
Perm.
Phytol.
Speidel,
Rev.
1874. Lehrbuch der
Skoog, F.,
of the
11
: 402-10.
Bot.
E. W.
New
xylem
567-75.
;
805-38.
:
Mechanism
Jour. Sci.
1944.
D. A.
of weak
of root
Bestimmung
zur
Wilkins
J.
IX The
28
Univ.
Sachs, J.
the
53
of the tomato due
systems
features
Physiol.
of various
70
1941. Control of
F.
Jour.
Bot.
Ann.
Austr.
F.
H.
root
into
Wet.
Akad.
677-83.
:
Salient
Plant
Ion-secretion
Ned.
538-77.
:
1951.
M.
N.,
roots
Bot.
Jour.
Rosene,
1950.
Kon.
excised
29
Wasserversorgung
Versuche
wiss.
N.
plant cells.
respiration.
Bot.
1936.
effect
10
plants.
R.
Robertson,
Arisz.
Proc.
uptake by
Jour.
absorption.
Die
Jahrb.
Robertson,
Plant
194-200.
:
O.
Wurzeln.
H.
1920. The mechanism
Naturwissenschaften
Renner,
W.
Steward.
of salt
1946. The
J.
O.
Renner,
rhythmic
conditions.
environmental
constant
exudation.
Water
1942.
van.
Physiol. 21
of the
1942. Preliminary investigation
under
and
of
regulation
and
G.
Raleigh,
of
salts
cytochrome system
accumulation
transpiration
problem
Priestley, J.
Simon,
of
influence
salt
non-osmotic forces.
Am.
of the
Properties
C. and
R.
van,
osmotic
Prevot,
of
of
472-80.
Overbeek, J.
to
1952.
in
17 :
Physiol.
to
translocation
183-92.
fluctuations
and
ANDEL
103-51.
:
1944. The
Montermoso, J.
Nie,
VAN
1088-91.
respiration
on
The
M.
oxygen
Plant.
1942.
2
:
323-42.
:
and
consumption
350-71.
Absorption and accumulation
Localization
in the root
Plant. Physiol.
17
S.
Lowe.
1950. The
of
sucrose
absorption by excised
mechanism
Physiol. 2
upon
Entwicklungs-
406-22.
;
:
of cation
accumu-
411-21.
carbohydrate nutrition
roots.
of tomato roots.
Ann.
Bot.
14
S.
N.
:
307-29.
Tagawa,
and
T.
1935.
The
concentration
relation
and
nature
between
of
the
the
absorption
surrounding
of
water
solution.
Jap.
by
plant
Jour.
root
Bot.
7
:
33-60.
Veen,
R.
van
der.
plant growth
Virgin,
Plant.
L.
H.
4
:
1950. A
under
small greenhouse
reproducible
1951. The effect
255-357.
with
conditions.
of light
on
artificial
Philips
lighting
techn.
the protoplasmic
Rev.
for
12
studying
(1).
viscosity.
Physiol.
THE
O.
Warburg,
des
INFLUENCE
und
W.
OF SALTS
Christian.
ON THE
1939.
EXUDATION
Isolierung
OF
und
D.
cells.
chrome
Went,
F.
W.
Jour.
Wiersum,
n6erl.
Wieler,
1944.
31
Ph. R.
White,
L.
41
A.
R.
N.
Austr.
:
:
Jour. Sci.
Plant
1950. Studies
accumulation
growth
Res.
B
under
processes
3
and
;
in
salt
the
metabolism
respiration
upon
of
plant
the
cyto-
487-500.
controlled conditions.
and
des Proteins
40-68.
growth
in
the
Ill
Correlations
tomato
plant.
Am.
597-618.
1938.
Bot.
K.
Robertson.
of salt
physiological
various
Bot.
Jour.
and
Dependence
system.
between
Am.
C.
VII
:
521
PLANTS
Kristallisation
oxydierenden Garungsferments. Bioch. Zeit. 303
Weeks,
TOMATO
25
“Root
:
pressure”
—
an
unappreciated force in
sap
movement.
223-27.
1947. Transfer of
solutes
across
the
young
root.
Rec.
Trav.
bot.
1-79.
1893.
Das
Bluten
der
Pflanzen.
Beitr.
Biol.
d.
Pflanzen
6
:
1-211.