LEh
67. '936
- M S" c?f
CYTOLOGY OF A F E R T I L E MONOPLOID
TOMATO.
bv
B.
A
Thesis
B.
Hillary
srfkmitted for- the Degree o f
MASTER
in
OF ARTS
t h e Department
of
BOTANY
THE
UNIVERSITY
OF B R I T I S H
September, 1936.
COLUMBIA
Table
of
Contents.
Acknowledgment s
Page
Introduction
1
Material
3
and Methods
Experimental
Somatic
Results
chromosome
counts
4
Mlcrosporogenesis
Prophase
Diakinesis
Metaphase I
Anaphase I
Interklnesls
Metaphase I I
Anaphase I I
Telophasell
Pollen tetrad formation
Possibility
Review
^
.
of Parthenogenesis
of L i t e r a t u r e
Summary
8
and D i s c u s s i o n
9
•
Bibliography
Description
"
4
4
6
6
"7
V
8
8
8
8
20
21
of Plates
23
Plate
I
26
Plate
II
27
A c k n o w l e d g e m e n t s.
The
W.Mr
Fleming
viding
in
and
writer
wishes
to express
f o r suggesting this
the material.
the cytological
Investigation
To D r . A . H . H u t c h i n s o n
work
t o Dr.F. Dickson
h i s thanks
t o Mr.
and p r o -
f o r Assistance
and p r e p a r a t i o n of the manuscript,
f o r help
with
photography.
CYTOLOGY OF A F E R T I L E
MONOPLOID
TOMATO.
Introduction.
The
loid,
not merely
literature,
tomato
well
1932.)
since
development
fertile
fruit
the f i r s t
The
part
observations
at the Dominion
British
Columbia,
roughness
cribed
round
shape,
grooves.
i s Irregular
These
i n serious
and n u t r i t i o n a l
elimination
instead
rough
of roughness.
plant.
In this
paper a r e
t h e cause o f
A rough f r u i t
that
Temperature,
des-
smooth a n d
i s with
corrugations
are rejected
have been
may b e
a regular
t o the growers.
studies
highly
a t Summerland,
t o determine
I n shape,-
losses
resulting i n
c a r r i e d on f o r t h e p a s t t e n
of having
fruits
f e r t i l e and
flowering
t o be r e p o r t e d
tomato.
as
a n d as f a r as c a n be
Experimental Station
i n the Earliana
chromo-
cells
i s the f i r s t
monoploid
I n an attempt
as one, w h i c h ,
resulting
ion,
This
of a series of Investigations
years
has twelve
parthenocarpic
variety
t o be a
i n somatic
t o be r e p o r t e d ,
fertile
haploldy"
i s considered
occuring,
seeds.
i n recent
"true
The p o l l e n i s h i g h l y
i s apparently
tomato
haploid
than hap-
o f t h e Ear11 ana
o f t h e genus,
with viable
monoploid
ascertained
the strain
number
rather
signifies
Investigation
as I n the gametes.
abundant
and
monoploid
i ti s naturally
or t h e b a s i c
ovule
i s used here
i ti s replacing
Thus
used I n t h i s
monoploid,
somes
"because
b u t because
(Darlington,
of
term M o n o p l o i d
by t h e c a n n e r s ,
Breeding, s e l e c t -
o f no a v a i l
i n the
e s p e c i a l l y the cold
- -
-2- .
night temperatures of the e a r l y summer seem- to have -some e f f e c t ,
g i v i n g an i n c r e a s e i n the anaaount o f -roughness.-- -Besides c o l d
the other main f a c t o r i n f l u e n c i n g roughness i s h e t e r o z y g o s i t y
i n the p l a n t s .a c o n d i t i o n which i s i n a c c o r d w i t h our p r e s e n t
3
day knowledge of KionoploS ds.
To date, c y t o l o g i c a l study has
not c o n t r i b u t e d g r e a t l y to the explanation and. s o l u t i o n of
roughness, as only roierosporogenesis has been
investigated.
thoroughly
However, t h i s process i s of i n t e r e s t since i t
d i f f e r s fro:a that d e s c r i b e d f o r o t h e r raonoploid p l a n t s i n
that there i s an equal d i s t r i b u t i o n of the chromosomes at the
tv/o d i v i s i o n s , v/hich are, i n effect,, two successive mitoses
d u r i n g which each chromosome d i v i d e s
twlce.
-3Material
The
during
B.C.
Two
Buds
the f i e l d
variety,
and blossoms
plots
representative
i n order
killing
was
Solution.
alcohol,
and
water,
25 c c .
was
material
could
8
acetic
through-
Both
be l e f t
was
t o 10 m i c r o n s
that
the material
(Schaffner's
caused
were
constituents:-
formula),and
Fixing
95 p e r
2ccj formalin,
some p l a s m o l y s i s
a n d was v e r y
5 cc;
because
length
and s e c t i o n s
and s t a i n e d
cent
b u t t h e B.C.
convenient
i n i t f o r an i n d e f i n i t e
imbedded i n p a r a f i n
used.
k n o w n a s B.C.
(glacial),
i n thickness
was
a n d n o t o f one p a r t i c u l a r p l a n t .
solution
the superior,
material
c o l l e c t e d a t random
solutions
acid
were
f o r com-
to insure
I t has the following
100cc;
Station,
was u s e d
an a l c o h o l - a c e t i c f l u i d
Fixative
The
grown
variety
and f i x i n g
One was w e a k c h r o m - a c e t i c
other
John Baer,
were
of the v a r i e t y
Two
the
i n v e s t i g a t i o n was
strains of the Earliana
A common d i p l o i d
parison.
out
for this
1933, 1934 a n d 1935 a t t h e D o m i n i o n E x p e r i m e n t a l
Summerland,
used;
material
and Methods.
o f time.
were c u t
with
i r o n alum and
with both
the monoploid
a
h^ema t oxy l i n .
Anther
and
diploid
stained
with
s m e a r s w e r e made
material,
f i x e d with Navaschin's
Gentian Violet
proved
quite
almost
entirely
(La Cour,
1931).
s o l u t i o n and
This
method
s a t i s f a c t o r y b u t t h e p a r a f i n m e t h o d was
as i t gave
series
of stages
i n single
used
anthers.
-4Experimental
Somatic
Chromosome
the monoploid
number
bud
were
used
coLints
tomato
counts.
wee made
i n root
and twelve
( F i g . 1).
observed.
tip c e l l s
chromosomes
I n order
w e r e made i n s o m a t i c
and s t y l e .
F i g . 3 shows
three
levels
shows
a late.anaphase
twelve
cells
F i g . 2 shows
cell;
show
chromosome
t o be sure
that
a side
of a nucleus
view
of the sepals,
a metaphase p l a t e
each
chromepetals,
i n a petal
o f metaphase chromosomes o f
i n an a n t h e r t i p c e l l ;
stage
of
or the x
f o r r n i c r o s p o r o g e n e s i s s t u d i e s was a m o n o p l o i d ,
some c o u n t s
anthers,
Earliana
Results.
i n a cell
and F i g . 4
of the style.
chromosomes w h i c h i s t h e m o n o p l o i d
A l l stages
number
f o r the
tomato.
Microsporogenesis.
In
the following
In
the monoploid,
to
those
stages,
are
not s t r i c t l y
applicable
nucleus
indefinite
substance.
number
at the last
consists
staining
With the beginning
number
of anastomosing
reduced.
reticular
Those r e m a i n i n g
the prophase
t o show
resting
that
bodies
this
they
preceding
reticulum
r e t i c u l u m a r e an
(Fig.5).
of the early
threads
stage
of a fine
S c a t t e r e d along
of dark
analogous
here.
In the microsporocytes
chromatic
particularly
be p l a c e d i n q u o t a t i o n marks
The
of
of microsporogenesis
to describe stages
occuring i n the d i p l o i d ,
will
meiosis
terms u s e d
description
prophase
becomes
thicken slightly,
the
greatly
forming
single
leptotene
(Fig.
6),
that
has
At l a t e
and the f i n e
the prophase
t h i c k e n and
8-$-.
normally
of the chromatic
show
This
takes
not been
connecting
progresses
corresponds
become
become
place.
The c o n t r a c t i o n
observed
i n this
less
evidence
caused
by
of p a i r i n g
o f them as w o u l d be
The
next
stage
known
as
stage
fixation.
synapsis
synizesis
although
takes
continue
i n diameter
a t which
monoploid
an a r t i f a c t
i s no
the threads
t o zygotene
probably
part
present, but
fibres
considerable variation
of the n u c l e a r c o n s t i t i e n t a
any
bodies
l e p t o t e n e the threads
traction
there
strands
(Fig. 7).
As
(Fig.
together by f i n e r
on the r e t i c u l u m a r e s t i l l
later.
thicker
distinct,
are joined
Sometimes t h e remains
disappear
little
to
which
were: s c a t t e r e d
these
a
threads
some c n n -
place.
Iti s
At late
"zygotene"
b e t w e e n t h e chromosomes o r
expected
i n a
diploid.
i s "pachytene"where
t h e chromosomes
h
thicken
and begin
evidence
to sorten i n length.
of having
paired
"Diplotene
It
for
i s customary
loops
monoploid
the
no
,
pairing
where i n n o r m a l
diploid
f o r t h e chromosomes t o s h o r t e n a n d t h i c k e n and
Earliana
t h e r e i s s h o r t e n i n g and t h i c k e n i n g of
took
place.
of this.
shows
a
meiosis
between the p a i r e d
but t h i s
10 A.
show
t o occur
stages
present
they
(Fig. 9),
parts.
chromosomes b u t no l o o p i n g , - a f u r t h e r
utive
Fig.
1 1
Again
F i g u r e s 10
The f i n e
i s the l a s t
a special
case
evidence
a n d 11 show
connecting
stage
Whereas i n t h e
two
fibres
at which
of a nucleus
they
that
consec-
are
still
were:seen.
at "diplotene".
Nuclei
of this
position
he
sort
o f some
occasionally
o f the threads
Perhaps
previous
to this
omes a r e b e g i n n i n g
At
expected
ance
to that
but
i n s t e a d of b e i n g
and
t h e number
same
has
i s prominent
i s 12.
as t h o s e
The
split
and
one n o t i c e a b l e f e a t u r e
halves
are
rounded
separated
process
but they
entirely.
the s p l i t
only w i t h
At
up
do n o t p o s s e s s
diploid
tomato.
nucleus
draw t o g e t h e r
spheres
losing
they
During
and t h e
(Fig. 13).
small
difficulty,
but
(Fig. 12).
a metaphase p l a t e
the
the u n i v a l e n t
t h e chromosomes
This
become
their
In-
I s formed at
c o n t r a c t e d chromosomes
c a n be
(Fig. 14).
metaphase of the f i r s t
regularly
the
until
i n the g r e a t l y
diploid,
o f t h e chromo-
to varying extents
disappear
appear-
are diads,
other
to form
Now
of a
them i s t h a t
and wandering
a
them a n
about
continues
and shrunken
dividuality
observed
giving
of the u s u a l
a n d n u c l e a r membrane
compacting
which
each
an u n -
Apparently
Individuality
"diakinesis"the univalent halves
nucleolus
line
repulse
not e n t i r e l y
late
present
u n i v a l e n t s are s c a t t e r e d throughout
widely
this.
the chromos-
of t e t r a d s they
stage,
was
chromatids.
place
i n the form
at this
characteristics
or e l s e
t h e chromosomes
taken
easily
substantiate
o f t h e p a i r e d chromosomes
of diads
parallel
hut nothing
would
They a r e " d o u b l e d " .
splitting
somes
daughter
"diaklnesis"
longitudinal
similar
that
parallelism
t o form
appearance.
of pairing,
stage
i t i s an a c c i d e n t a l
and the
a n d chromosomes m i g h t
I n t e r p r e t e d t o "be t h e r e s u l t
-observed
occur
at the e q u a t o r i a l
division
plate
and a
the
chromosomes
bi-polar
spindle
i s always p r e s e n t .
daughter
to
univalents
each pole
regular
Figure
17
varying
degrees
attached
of
anaphase these
pole
(Fig. 18).
kinesis.
complete
somes
Figure
with
at t h i s
observed
consistent
that
m e t a p h a s e 1,
which
are placed
shows
and
nucleolus
apart
i s a definite
t h e two
a later
stage
and d e f i n i t e
At
i n the form
chromosomes.
together
reorganization
n u c l e i at early
where
inter-
the n u c l e i are
chromosomes.
The
chromo-
and i n d i v i d u a l i t y .
It
the i n d i v i d u a l i t y
o f t h e chromosomes
was
c o u l d be i d e n t i f i e d
and i n t e r k i n e s i s ,
s i d e by
become
chromosome.
being
shov/ d o u b l e n e s s
Following
chromosomes
the spindle
do n o t p u l l
shows
a n d t h e same t y p e s
esis,
attachment,
1 t h e chromosomes mass
there
20
nucleoli
stage
spindle
show
(Fig. 19).
Figure
21
cases.
of which
of paired diploid
At telophase
interphase
the nucleus.
i n these
a
12 chromosomes m o v i n g r e g u l a r l y t o e a c h
aggregation
At
was
of the arc-shaped
V's a s i s c h a r a c t e r i s t i c
i n Figure
on t h e s p i n d l e ,
attachment,
chromosomes
regularly
o f t h e 12 c h r o m o s o m e s a t
or terminal
one a t e l o m i t i c
t o the centre
a loose
formed
twelve
as shown
metaphase, e l e v e n
of t e l o m i t i c
a n a p h a s e shows
of
not being
the i n d i v i d u a l i t y
Late
in
univalents)pass
are scattered
during T i r s t
the other
early
univalents
shows
anaphase t h e
I n a few odd c a s e s
metaphase p l a t e
"disjunction"
and
(or halved
(Fig. 15).
,16 t h e d i v i d i n g
In early
side
smaller
disappear,
- s e e f i g u r e s 1 2 , 17, 2 1 ,
to facilitate
the double
at diakin-
stage
and rounded,
comparison.
during
interphase
the nuclear
the
membrane
and t h e second metaphase p l a t e s a r e
formed
with
well-defined
chromosomes
divide
regularland
orderly
spindle
24).
fibres
Upon
groups
shape
their
fertile
was
at t h i s
tetrads
determined
full
this
from
r e a d i l y on t h e s t i g m a
pollen
tubes
but
is
fertilization
not s u f f i c i e n t
embryos w i l l
normal but there
elopment
can
that
be d e s c r i b e d
chromosome
and a
nucleolus
their
and these
spherical
break
of heavily
cent
buds.
stained,
anthers.
apart
90 p e r
for different
This
well-
Pollen
i s packed
seen t o enter
on t h i s
to take
point
germ-
with
examined-before
place.
a great
completely.
t h e embryo s a c ,
place,
however
y e t , a n d many
there
more
i t c a n be p r o v e d
that
Endosperm development- a p p e a r s
are c e r t a i n p e c u l i a r i t i e s
require
the
P o l l e n i s about
not observed
evidence
takes
anaphase the
down i t .
have t o be
parthenogenesis
i n
defined (Fig.
lose
and the s t y l e
n u c l e i were
was
stage
i n various
inates
Pollen
poles
are formed
c o u n t s made
passing
At l a t e
membrane
figure varies
pollen grains
to the poles
of
(Fig. 25).
into pollen grains.
although
rounded
a nuclear
elongated
Both groups
a r e not c l e a r l y
respective
chromosomes
a n d become
develop
by
and pass
( F i g . 23).
the poles
reaching
Pollen
and
manner
near
The
( F i g . 22).
simultaneously
are surrounded
appears.
spindles
deal
more
i n t h e embryo
research
dev-
before i t
-SiReview
of
Haploid
^genera
of
flowering
L i t e r a t u r e and
sporophytes have
been d e s c r i b e d
plants.
Oenothera,
Trlticum,
Grepis,
Brassica,
loids
smaller
than
are
certain
other
almost
crossing
to
cold
with
at
the
Datura,
Matthiola,
diploids,
alterations In
completely
a
the
sterile.
distantly
time
"spontaneously".
Discussion.
of
form
these
and
with
and
Solanum.
smaller
fertilization
(Prom a
summary
of
and
Gates
the
and
and
are
after
after
In
hap-
cells
(a)
(b)
(c)
The
They
appeared
related species,
eight
Nicotiana,
character.
have
in
subjection
tomato,
Goodwin^,
1930) .
The
any
of
the
; loids.
the
diploid,
slightly
lighter
floral
and
above
This
noticeable
monoploid
described
yet
It
is
smaller
colored
than
two
two
i n large
as
is
customary
is
a p p r o x i m a t e l y mid-way
the
(1934).
cell
for
size
The
other
a
that
truss
between
In
The
of
of
a
rule,
cyme
cells
reported
by
originated
from
of
diploids
the
tomatoes
copied
exposing
as
measurements
monoploid
than
following:
a hanging
size
hap-
number
are,
to
most
the
the
fruits
diploid
following history Is
are
t h a n i n most
insfeead
the
the
Inwards
increase
varieties.
this
field
stamens;
o f . h a p l o i d and
I t appears
taneously".
on
an
conform
smaller
Among
curling
more p a r t s
extra
borne
for
numbers
smaller.
edges
surface;
, usually
o f t e n more
noticeably
observed i n the
with
not
characteristics for
i s not
slightly
leaves
under
tomato does
general
monoploid plant
differences
parts
Earliana
Humphrey,
"spon-
U.S.D.A.
-10Miscellaneous
in
1900
The
by
P u b l i c a t i o n No.
the
original
,N.J.
and
plant
firm
stock
condition
only
in
paper.
the
from
celling
and
cytology
low
that
of
any
Blakeslee
of Datura
c h r o m o s o m e s s h o w no
and
random
10,
3
and
to
9,
non-reduction.
somes
after
rnetosis
in
the
a
where
usual
microspores,
the
4
and
short
time
8,
anaphase
of the
monoploid
or
developed
5
give
Earliana
i s
an
subjecting
other
and
segregation
pass
the
equal
are
and
and
the
developed
division
these
the
the
and
metaphas
either
11,
there
of
are
very
be
chromo-
distributed
form
2
4
small
equal
chromosomes
organize
may
2
homeotypic
when i r r e g u l a r i t i e s
give
plants
12
but
groups
and
of
the
1
or
through a
smaller
tomato
The
at
of
6),
halves
W.M.
described
account
( i n assortments
6
this
described,
microsporocytes
7,
not
Mr.
fertilization.
f o r each
and
by
seed
i f
S t a t i o n and
Such microsporocytes
first
main groups
of
the
d i v i d e s and
usually 2
Polyspores
In
Interphase
manner.
does
p r o d u c e d by
poles
I f there
each
1927)
single
author
monoploid
attraction
the
larger.
of the
(1927,
a
Salem,
grown from
haploid previously
heterotypic mitosis
at
are
strains
the
haploids
at
The
of
from
tomatoes
Experimental
of
Sparks,
developed
of
introduced
of P h i l a d e l p h i a .
George
Stone."
i n the
cytology
temperature
the
Stokes,
been
field
name o f
Summerland
The
move
to have
exists
at
differs
and
a l l E a r l i a n a tomatoes
Fleming
this
the
" E a r - l i a n a was
p r o d u c e d by
s e l e c t i o n made i n a
know w h e t h e r
of
Johnson
was
i s reported
purchased under
to
of
160:
small
and
during
Independent
cells
in
-11addition
to
the
constitute
the
mass
Non-reduction
,the
halves
pollen
12
are
at
two
of
the
pass
first
regularly
fertile
when t h e
i n two
total.
The
not
similar
In
the
tomato
the
well
is
small
12
12,
set
haploid
since
in
split
and
of
grains'Which
and
chromosomes.
latter
the
chromosomes
at
the
second
p i l e s i n each
about
Earliana
and
as
and
two
make up
the
grains
developed.
chromosomes
haploid
Datura
are
to
12
the
these
which
sets,
good p o l l e n
d i v i s i o n as
A l l of
pollen
each with
the
divisions
the
place
result
tomato monoploid
are
abortive
distributed
constitute
percent
of
takes
grains
These
4 principal cells.
and
there
divide
12
halves
division resulting
in
pchllen.
o
Chipman and
study
of
Nicotiana
reported
meiosis
produced.
izesis
the
in
then
of
the
the
24
was
i s followed
are
often
the
some o f
Univalents
and
when r a r e l y
giant
spindle
and
the
grains
of
which
with
a full
of
set
threads
24
a
the
of
had
24
pollen
before
syn-
Synizeses
single
in
spireme
chromosomes.
Bipolar
random d i s t r i b u t i o n
pass
divide
during
divide
there
dyads
from
haploids
occasionally
a l l 24
formation
haploid
some v i a b l e
and
sometimes
mitosis
pollen
set
cytlolgical
two
haploid.
pachynema
typic
Into
i n the
haploid
the
the
the
formed r e s u l t i n g In
chromosomes
cytoplasm.
by
not
a
Thss h a p l M d
but
of
of
of
(1924).
pairing
d i p l o i d but
segments i n t o
spindles
Mann
one
female sfeerile
There
the
haploid
and
was
( 1 9 2 7 ) made
microsporocytes
var.purpurea,
Clausen
chromosomes and
was
i n the
tobacum,
by
Goodspeed
the
hetero-
results
which might
haploid
into
a
develop
chromosomes.
-12Her-e t h e r e
division,
the
is a
hut
tomato
this
and
A
was
described
one
of
lings
the
at
a
division
i s not
pollen
i t s origin
treatment
random
with
had
with
var.
24
purpurea
plant
and
features
sterile,
cells
had
and
mother
these
cell
divide,
19
while
fragmented
70-72
Out
loid
1000
a
into
rest
plant
flowers
white
of
N.
of
W.
glutinosa
plant
x-rays
as
was
seed-
unconnected
crossed
and
with
flowers
purpurea.
36
bivalent
and
173
plants
was
I t was
In
one
The
latter
had
a
identical
in
completely
i t s pollen
mother
random.
chromosomes were
separated,
chromo-
identical
flowers.
d i s t r i b u t e d at
univalent
N. L . d i g u l a t a ,
tabaccum,
white
chromosomes
In
seen
half-univalent
one
to
being
two.
(1929),
obtained
of M c o t i a n a
with
seedlings
pollen
one
a haploid
by
pollinating
Tabaccum •macrophylla
of
N.
Langsdorffii
reached maturity.
L a n g s d o r f f i i , somewhat
having
(1929)
i n having
haploid
the
the
in
chromosomes were d i s t r i b u t e d
form
were u s u a l l y
chromosomes
of
12
as
formed.
This
to
and
F]_, c o n s i s t i n g o f
univalent
of
(1929).
first
division
are
line
subjected
hammerts
of
small
Kostoff
aberrant
been
The
except
with
24
tetrads
Avery
the
second
i n a pure
and
carmine
The
with
not
a
at
meiosis.
pollen
bivalents.
single
other
the
by
"spontaneous"
received.
allahexaploid with
somes,
an
was
in pollen
and
occuring
Goodspeed
Clausen
an
followed
c u l t u r e which had
but
a l l univalents
dyads
haploid
by
of
smaller
9 L a n g s d o r f f i i chromosomes.
than
the
This
(n
was
diploid
In p o l l e n mother
having
-
9).
a
hap-
and
cells
-13the
9 chromosomes
spread
out towards
random.
.first
at
the p o l e s
Sometimes
division.
they
forming
or more groups,
resulting
dyads.
of which
triads,
appears
a l l univalents divide
Mo.
and A i s e
t h e time
winter
There
appeared.
sterile.
meiosis
i n the microsporophytes
are
or there
may
homeotypic m i t o s i s
the
chrornsomes
Aegilops
polyspory.
Earliana
Q%
with
Triticum
compactum
cylindrica.
the female
The
parent
irregularly
be a m i x t u r e
many
there
each.
during
99.8
during
probably
chromosomes
the heterotypic
o f t h e two p r o c e s s e s .
the d i s o r d e r l y
Irregularities
No n o r m a l p o l l e n
were
The
char-
about
o f chromosomes
because
g r a i n s were
of
tomato
a haploid
T h e p l a n t was
o f 7 chromosomes
continues
giving
About
division.
wheat,
was n o p a i r i n g
generally distributed
mitosis
with
o f f l o w e r i n g when p e c u l i a r i t i e s
of s t e r i l i t y
sets
spindle,
two
t o be t h e g e n e r a l
(1926) o b t a i n e d
by p o l l e n a t i n g
dissimilar
into
octads.
seems
at the f i r s t
percent
three
group
second
separate
or even
c o u l d n o t be d i s t i n g u i s h e d f r o m
acteristic
i n the
i n the monoploid
(42 chromosomes), w i t h
128 u n t i l
remain i n a
i t s own
chromosomes
where
haplMd
forms
i n the
h a p l o i d s , random d i s t r i b u t i o n
Such i s n o t the case
humboldtii
T h e y may
pentads
rule.
Gaines
divide
good.
undivided'univalent
21 c h r o m o s o m e s
of the spindle and separate a t
o f t h e chromosomes
With NIcotiana
the
p l a t e , but
a l l frequently divide
pollen
each
pollen
the pollen
some
an e q u a t o r i a l
When a l l t h e c h r o m o s o m e s
interkinesis
division
of
do n o t f o r m
-
distribution
The
of
and forms o f
observed
to
develop
although
such might
sometimes
coalesce
respects
,being
this
However
giant
splitting
this
i s not
obt a i n e d
two
chromosomes
haploid
vd-th o n e
mitosis
as
two
of
the
at
extra
evidently
being
some
l^plold
univalent
dicision.
tomato.
and
Frost
o f w h i c h was
In
some c a s e s
extra
fragment)
omitted.
This
(1928)
described
the
there
chromosomes f o l l o w e d
chromosomes
split
the
(1928)
diploid
chromosome f r a g m e n t s ,
the
the
the
Lesley
one
cells
In
the
first
hybrids,
haploid
sometimes
the
and
i t i s i n the
dwarfs,
Frequently
tomato,-
others,
such fragment.
Irregularities.
(except
rule
extreme
with
segregation
arate
the
some M a t t h i o l a
i n Fg
the
lengthwise
the
P o l l e n mother
pollen grains.
haploid ressembles
In
dom
forming
i n d i s t i n g u i s h a b l e from
chromosomes
(14
r a r e l y tee f o u n d .
other
is
by
ranother
and,;s"ep:-r:jG
heterotypic
results i n
pollen
dyads.
Hollingshead
uals
of
Grepis
capillaris
foreign
G.
pollen
formed.
this
x
The
t u t o r em.
i s the
cytology
article,
aLithor which
capillaris
and
(n
-
3)
for
of
i s not
with
the
of
a
c e r t a i n vi/hether
e x c i t i n g cause
the
haploid
among p r o g e n y
I t i s not
haploid
unfortunately
deals
two
the
1930
the
Individcross
cold
haploid
described
paper
c y t o l o g i c a l study
by
was
or
being
in
this
not
C.
same
avail-
able .
Emerson
in
an
atypical plant
Oenothera
The
(1929) d e s c r i b e s
franciscana
spireme
i n the
appearing
x
the
in
the
hybrid
p o l l e n mother
the
F-^
reduction
from
franciscana
cells
of
this
the
division
cross
sulphurea.
haploid
is
not
-15continuous
apsis.
and p a r a l l e l i s m o f t h e threads
P a i r i n g was
as
i n the d i p l o i d .
is
thirown i n t o
each
other.
segments
t h e arms
second
t o the center.
t h e tomato
by D a v i s
mutation
the thread
end t o end.
v's with
about
thickens
divide
and
Anaphase
spindle
i s no s i m i l a r i t y
fibres
between
this
stages
at the f i r s t
of sterile
division
that
nucleus
to the period
formed.
by
Here
ofcthe
attached
"pointed
tips".
segments i n t o 7 chromo-
(6^-1),
of the
( 5 A- 2 ) ( 4 h 3)
p o l l e n grains are
becoming u n i p o l a r , the
to the spindlesfibres
mitosis
being
a n d t h e chromosomes
omitted,
split.
the
This
of i n t e r k i n d s i s and i s followed
spindle
the formation
omission
haploid
Functional
spindle
homeotypic m i t o s i s
t o each pole
one I s a
distribution
mitosis
The h e t e r o t y p i c
Is reconstituted
an o r d i n a r y
grains
Irregular
a l l becoming
pole.
corresponds
pass
the spireme
pollen.
i n Oenothera i s
This
and i s c a l l e d
of the multipolar
chromosomes
haploid
(1930).
i n the heterotypic
a mass
result
from
cells
w l i i c h do n o t p a i r .
gives
the
of another
i n Oe. f r a n c i s c a n a
chromosomes
is
continuous and
i s no p a i r i n g i n t h e p r o p h a s e
and l u l k a r n i
t h e p o l l e n mother
somes
by
appears
frequently
are d i s t r i b u t e d regularly.
given
7
formed
a n d t h e chromosomes
An account
In
contraction
There
as there
"but n o t a s
a t syn-
of which a r e twisted
have n o t t h e t y p i c a l
the tomato
and
stages
t h e spireme
i n t o 7 chromosomes
attached
of
a t many
Later
loops,
After
chromosomes
and
seen
i s common
i n which
seven
and a dyad
of a dyad
of the reduction
of pollan
of f u l l
division
chromosomes
grains
sized pollen
i s similar to that
-16found
by
Belling
comparable
to
and
the
Other
U-ates a n d
The
described
327
fertility,
may
and
the
that
continuous
formed.
were
to
of
the
of
of
phrey.
tomato
a
But
cross
by
Oatcheside
similar
to
those
regarded
sterile.
given
to
the
as
In
Humphrey
particular
lie found
but
i t was
t h i c k e n i n g and
which e x i s t e d
observations
tomato
longitudinally
regular mitosis, In
shortening
groups
of
The
from
the
these
with
to
of
the
very
the
closely
and
the
stages
with
chromosomes
split
w h i c h 12
prophase
of
first
In
those
the
two
cyt-
emphasis,
threads
of
plate
present.
special
leptotene
believed
combinations
on
lack
form
as u n p a i r e d u n i v a l e n t s a t
agree
diakinesis
a l l
cyt-
(1931).
metaphase
(1934) d e s c r i b e s
haploid with
single
the
prophase
O c c a s i o n a l m i c r o n u c l e i were
appeared.
of
Koos
unigorm,
g
spontaneous.
and
but
P
complete
Lindstrom
irregular
has
i n the
account
was
at
chromosomes
showing
Distribution
Earliana
are
and
I t appeared
No
and
author's
ploid
b)
12
present.
prophase,
chromosomes
The
occur.
and
was
this
pairing
a varietal
t h e r e f o r e be
was
with
(1929).
c y t o k i n e s i s were n o t
six cells
ology
a
spireme
observed.
results
at a l l
been r e p o r t e d
i s somewhat
h a p l o i d i s g i v e n by
attention
was
of
completely
Little
a
(1930
tomato mutant
Lindstrom
plants
and
i s dwarf
of
Stomps
i s not
divisions
h a p l o i d s have
of these
hap&oid
d e s c r i b e d by
ology
two
but
above.
numbering
It
(1930^,
cytology
A
been
tomato where
Oenothera
Goodwin
(1932J.
Blakeslee i n Datura,
diakinesis.
the
mono-
o f Hum-
Earliana
division
h a l v e d u n i v a l e n t s pass
is
to
each
pole
and-are-distributed
r e g u l a r l y and
- n o t - a t -random a s
in
o t h e r - - h a p l o i d . - - -Humphrey - s o m d t i m e s - o b s e r v e d - t h r e e - s p i n d l e s
the
second-division
, n e v e r -observed..
from
whereas-in-this
Also
non-reduction
asionally
formed,
normal
at
but
the
i n
spores
first
the
Earliana
to
cross
iculty.
but
-The
sac
they
two
pollen
fall
to
fuse-with
the
or
12g
development.
The
always
are
of
often
i n the
plate
range
Univalent
At
being
polar
from
the
egg
From
l u t e u m may
3
of
can-be
the
diffthe
sperm
endosperm
nuclei
nucleus
unfertilized
i t i s more
than
come f r o m
likely,
partheno-
d l a k i n e s i s show some
haploid
at
number-of
pairs
of pairs
;
present
scattered
12
on
with
the
recognized
the
by
from
to
11
reduction
of
the
only
equatorial
the
number
numbers
near
a
3
metaphase
through
The
microsporo.cytes
ranging
suggest
heterotypic
regions.
to
with
enter
i t s two
and
some
and
only
the
chromosomes l y i n g
products
cross
i n the
the
constantly
univalents
would
att-
During meibsis
l a r g e , number
t 12-j_ t y p e .
their
occ-
interesting descript-
discharge
develop
of p a i r i n g , the
12,
h e x a d s -are
tetrads* are
which produce h a p l o i d s
chromosomes
valents
the
seeds
to
an
Solanum
and
disintegrate.
that
degree
and
T h e s e were p r o d u c e d by
that
of
Higrum
embryos b e g i n
30
tiibe
S.
eggs
genetic
species
of
and-finally
the
gives
some S o l a n u m h a p l o i d s . -
embryo
were
..
J o r g e n s e n 1928,
empts
at
o c c a s i o n a l l y -result
division,
formed.
i o n -of
monoploid-three
the
of
of
5
cells
bi-
plate,
and
most
bivalents
on
to
frequent.
8 most
p l a t e may
their
the
small
divide
size.
the
and
The
chromosomes p a s s
from
15
to
more
commonly
^divide
22
and
usually
with
w i t h 18
certain
This,
as
Jorgensen
of
3
sets
apsis.
of
o f 12,
sufficient
two
of
similarity
where t w e l v e ,
some n u m b e r
of
the
found
i n Solanum nigrum
lated
luteum
entering
seen
to
egg
though
they
pollen
nucleus
ceedure
task
to
see
enogenesis
genesis
pollen
was-not
at
any
that
embryo
can be
the
grains
Solanum h a p l o i d
out,
be
suggests
a group
that
number,
to
the
composed
of
together i n a true
expected
is
mito-
c o n t a i n homologues
them
that
was
the
In
embryo
came f r o m
to prove
many m o r e
the
sets
the n u c l e i
nucleus."
enter
4
these
occur
syn-
in
i s the b a s i c
the
chrome-
genus.
by
the
these
the h a p l o i d
caused
with
giving
constitute
c o u l d not
stimulus
S.
of
(1928) p o i n t s
to bring
Jorgensen
velopment
mitosis
chromosomes i n the h e t e r o t y p i c
the h a p l M d
Such b e h a v i o r
tomato
homeotypic
at metaphase,
regularly
peculiarity
of
chromosomes
The
ranging
chromosomes.
striking
36
p o l e s i n numbers
chromosomes
anaphase proceeds
pairing
sis.
to the
18 m o s t - f r e q u e n t . -
p r e s e n t s 18
A
the
irregularly
the
the
from
and
but
sacs-will
have
definitely
of
sac but
same p l a n t ,
time,
of a
distantly
failing
fusion
tube
of
the
does
t o be
still
not
In
the
more
take
re-
to
fuse
was
nuclei,
egg
Thi's i s a d i f f i c u l t
i t i s a
de-
fertilization
the p o l l e n
and
pro-
difficult
place,
and
examined b e f o r e p a r t h -
demonstrated.
place
embryo
d i s c h a r g e i t s two
observed.
take
pollen
tomato
fertilization
i s shown t o
result
embryo
the
sac
parthenogenetic
tomato
If
partheno-
and
the
pec-
--• -
-19-
ullarities
of-the
vid.ll
e x p l a i n how
life
cycle
of
viable
seeds
this monoploid
The
matoes
e n s u i n g -embryo d e v e l o p m e n t - c l e a r e d -up i t
the
Earliana
when u s e d
i n the progeny
cytological
of
non-homologous
zygous.
This
was
as
the
were homozygous
tomato
considering
rough.
that
translocation,
chromosomes
there
This
mutations
but
as
irreg-
as y e t
no
made.
are but
one
i t i s not
homo-
not b e i n g
which
t h e s e same
can perhaps
resulted
set of
Summerland
strains
Later
or r e d L i p l i c a t i o n
(1932).
apparent
Fleming at
shape.
of the monoploid
Darlington
life
with other to-
(self-fertilization
f o r smooth f r u i t
by
(1930) and
though
been
i s self-pollinated)
plained
the
these crosses,
selection
became h o p e l e s s l y
disjunction,
a r e no
d e m o n s t r a t e d b y Mr.
strains
of
There
chromosomes i n i t s c e l l s ,
developed by
necessary
i n crosses
examination of these has
This monoploid,
a n d how,,
perpetuated.
seems t o a c t n o r m a l l y .
uliarities
when h e
are produced,
from
be
non-
of small
s u g g e s t e d by
ex-
portions
East
Summary1. ••• C h r o m o s o m e
sepals,
petals,
anthers
, b e r o f chromosomes
basic
number
with
is
no
no
evidence
threads
of p a i r i n g
and the
stages
show
single
stages
show
a t h i c k e n i n g and
t o form
having
At d i a k i n e s i s
to a longitudinal
leptotene
chromosomes,
taken
there
place.
t h e chromosomes
splitting.
and
There
are
:
'doubled"
a r e 12 d i a d s
o r 24
halves.
5.
univalent
prophase
L a t e r prophase
of these
monovalent
num-
pairing.
4.
due
of root t i
a n d - s t y l e , r e v e a l e d the somatic
t o b e -12, t h e m o n o p l o i d number
Early
3.
shortening
made I n t h e c e l l s
f o r the genus.
2.
threads
counts
A regular-metaphase
halves
pass
regularly
plate
I s formed
and the
e x a c t l y as I H a
t o each p o l e
homeotypic m i t o s i s .
6.
constituted
uality
At i n t e r k i n e s i s
the nucleus
and t h e chromosomes
appear
7.
show
The
chromosomes
at diakinesis,
first
i s definitely re-
double.
characteristic
metaphase
disjunction,
individand
inter-
kinesis.
8.
The
second
12 c h r o m o s o m e s
passing
9.
Pollen
pollen
i s 90 p e r c e n t
10.
elopment
t o each
i s normal
of the four
i n a l l respects
poles.
t e t r a d s are formed and the
resulting
fertile.
Evidence
and t h e seed
division
suggests
parthenogenetic
prodiiced i s about-85 p e r cent
embryo
dev
viable.
-21B i b l i ography.
B e l l i n g , J . y a n d B l a k e s l e e , - A . : F V , 1925, -The R e d u c t i o n D i v i s i o n
i n Haploid, D i p l o i d , ' T r i p l o i d and"Tetraploid Daturas.
P r o c . H a t . A o a d . - S c i . , 9, 106-111.
B e l l i n g , J . , and B l a k e s l e e , A . F . ,
1957,
Chromosomes-in-Haploid Daturas.
The a s s o r t m e n t o f
- C e l l u l e , 37,-355-365.
C a t c h s i d e , D . G . , '1932, The C h r o m o s o m e s
Oenothera.
G y t o l o g i a 3.
of
a New
Haploid
•
: Chipman,R. H., a n d G o o d s p e e d , T.H. , I n h e r i t a n c e i n N i c o t i a n a
Tabacum, V l l l .
G y t o l o g i c a l F a t u r e s of purpurea haploid.
U n i v . C a l i f . Pub. B o t . 11, 142-158.
:
;
e
C l a u s e n , R . E . , a n d Lammerts,W/E., 1929,
i z a t i o n i n N i c o t i a n a X. H a p l o i d
- Amer. N a t . 63, 279-282.
I n t e r s p e c i f i c Hybridand
fiiploid
Nerogony.
C l a u s e n , R . E . , a n d Mann, -M..C. , 1924,
Inheritance In Nicotiana
Tab acuta V.
The o c c u r r e n c e o f h p p l o i d p l a n t s i n i n t e r s p e c i f i c progenies.
P r o c . N a t . A c a d . S c i . , 10,
120-
--124. --
Davis,B.M.,- a n d K u l k a r n i , C . G . ,
e t i c s of a h a p l o i d s p o r t
G e n e t i c s , - 1 5 j 65-80.
1930,
from
The, C y t o l o g y a n d G e n Oenothera f r a n c i s c a n a .
D a r l i n g t o n , C D . , 1932.
Recent Advances In
Cytology.
P. B l a k i s t o n ' s S o n a n d Co. I n c . P h i l a d e l p h i a . D e s c r i p t i o n of Types of P r i n c i p a l American V a r i e t i e s of
• . T o m a t o e s ; U.S.D.A. M i s s c e l l a n e o u s
P u b l i c a t i o n No.
E a s t , E . M . , 1930, -The P r o d u c t i o n
• • - induced Parthenogenesis.
160.
of Homozygotes through
S c i e n c e 72,
148-149.
E m e r s o n , S . H . , 1929,. The r e d u c t i o n d i v i s i o n
-Oenothera.
C e l l u l e , 39, 159-165.
G a i n e s , E . P . , a n d A a s e , H . C , 1926,
A
Amer. <T. B o t . , 13,
373-385.
haploid
in a
haploid
wheat
plant.
G a t e s , R . R . , a n d G o o d w i n . K . M . , 1930,
A new H a p l o i d O e n o t h e r a ,
w i t h some c o n s i d e r a t i o n s on H a p l o i d y i n P l a n t s
and
Animals.
J . G e n e t . , 23, 123-156.
Goodspeed,T.H,,
Nicotiana
15,
502-504.
Hollingshead,L.,
Sapillaris
134.
a n d A v e r y , P . , 1929,
g l u t i n o s a Haplont.
1930,
A
Plants.
The o c c u r r e n c e o f a
Proc. Nat. Acad. S c i .
c y t o l o g i c a l study of H a p l o i d
Crepis
U n i v . C a l i f . Pub. A g r . S c i . , 6,
107-
H u m p h r e y , L.M.-, The M e i o t i c D i v i s i o n s o f - H a p l o i d ,
T e t r a p l o i d 1'omatoes w i t h S p e c i a l R e f e r e n c e
P r o p h a s e . - G y t o l o g i a 5, No. 3, 2 7 8 - 3 0 0 .
Diploid
t o the
and
Jorgensen,C.A.,
1 9 2 8 , The E x p e r m i n t a l F o r m a t i o n o f H e t e r o p l o i d P l a n t s i n t h e G e n u s S o l a n u m . J . G e n e t . , 19,
133211.
K o s t o f f . D , , 1929,
Zdllforsch,
Am
u.
androgenic NIcotlana haploid.
m i k r . A n a t . 9, 6 4 0 - 6 4 2 ,
Zeits.
f.
Lesley,M.-M. ,- a n d F r o s t s H . B . , 1 9 2 8 , Two e x t r e m e " s m a l l "
M a t t h i o l a p l a n t s ; a h a p l o i d w i t h one a n d a d i p l o i d
w i t h two a d d i t i o n a l c h r o m o s o m e f r g g m e n t s .
Amer. N a t . ,
62, 2 2 - 2 3 .
L e s l e y , M . M . , 1926, M a t u r a t i o n i n D i p l o i d
G e n e t i c s , 11, 267-279.
.Lindstrom,E.W., 1929, A h a p l o i d m u t a n t
, H e r e d . , 20, 23-30.
and
triploid
i n the
tomato.
Tomatoes.
J.
L i n d s t r o m , E.W.~, a n d K o o s , K. , 1 9 3 1 , C y t o g e n e t i c i n v e s t i g a t i o n s
o f a h a p l o i d tomato and i t s d i p l o i d and t e t r a p l o i d
progeny.
A m e r . J . B o t , , 18, 3 9 8 - 4 1 0 .
Sharp,L.W., 1934,
New
York.
Introduction
to Cytology.
McGraw-Hill,
S t o m p s , T . J . , 1 9 3 0 a , Tiber P a r t h i n o g e n e s i s i n f o l g e
Frembefruehtung b e i Oenothera.
Z . I . A . V . , 54,
S t o m p s , T . J . , 1930
Ber. Deuts.
b, Uber P a r t h e n o g e n e t i s c h e
B o t , G e s . , 48, 1 1 9 - 1 2 6 .
243-245.
Oenothera.
-23D e s c r i p t l o n of Plates.
All-drawings
giving
the
weremade
with
d r a w i n g s were
reduced
Pig.
somatic
one
chromosomes.
In reproduction
half.
•
Metaphase p l a t e
2.
Metaphase p l a t e
Adjacent
i n a root t i p c e l l
showing
i n a petal
to i t i s a resting
cell
nucleus
with
also
12
with
chromosomes.
Fig.
tip
1.
lucida
chromosomes.
Pig.
12
a camera
a m a g n i f i c a t i o n o f 3700- d i a m e t e r s .
Plate-1.
12
-
cell
showing
3.
Three
a side
levels
view
of a nucleus
i n an
o f t h e 12 c h r o m o s o m e s
anther
a t meta-
phasw.
Fig.
4.
Late
,12 c h r o m o s o m e s p a s s i n g
Fig.
stage
prior
5.
anaphase i n a c e l l
t o each
of the
style,
pole.
Microsporocyte
nucleus
at l a s t
resting
to meiosis.
Fig.
6.
Early
leptotene, threads beginning
to
thicken.
Fig.
thicker,
leptotene, single
fibres
are less
8.
"Zygotene"
-9.
"Pachytene".
threads becoming
distinct.
with lack
of p a i r i n g
between
chromosomes.
Fig.
evidence
of having
Fig.
lack
Late
the connecting
Fig.
the
7.
chromosomes
show n o
been p a i r e d .
10.
Early
the c h a r a c t e r i s t i c
diploids.
The
"diplotene".
looping of paired
The
chromosomes
p a r t s as i n
Fig.
earance
in
of
feeing
the formation
Fig.
chromosomes
due
repulse
each
ing
i n order
dividual
Diakinesis.
widely
17.
irregular
chromosomes
a r e "doub-
The u n i v a l e n t h a l v e s
individuality.
of metaphase 1 a t the
The c h r o m o s o m e s
21.
The
a n d show m a r k e d
view
-
diakinesis.
splitting.
Side
•
stage
are separated
out t h e i r
time
i n t h e draw-
individuality,
Interkinesis.
c a n be p i c k e d
Note t h a t
certain i n -
out a t t h i s
stage,
a n d metaphase.-
Fig.
has
12.
-
and t h i c k e n e d
" d i p l o t e n e " and
c h r o m e somes
diakinesis,
i s - b e l i e v e d t o he a
chromatids.
Shortened
to bring
-Fig.
of
11.
other
disjunction.
o f t h e chromosomes h a v e t h e app-
of daughter
to a longitudinal
Fig.
of
Some
paired, hut this
of late
Fig.
led"
10 A ,
the diads
13.
Late
are-drawing
diakinesis.
closer
The u n i v a l e n t
together
halves
and the n u c l e o l u s
d i s a p p e a r e d "accompanied by t h e breakdown o f t h e n u c l e a r
membrane.
Fig.
passing
regularly
Fig.
equatorial
plate
Fig.
to
each
15.
Early
a n a p h a s e 1,
daughter
univalents
to poles.
16.
E x c e p t i o n a l case
i s not
where
a regular
formed.
18,
La'te a n a p h a s e ,
14.
Metaphase p l a t e
12 c h r o m o s o m e s
passing
pole.
Fig.
contracted
spherical
chromosomes.
of f i r s t
division
with
-•
Fig.
have
19.
- F i g . 20.
not y e t acquired
Fig.
dicate
passing
that
22.
-25-
-
Telophase
1.
E a r l y -inter kine si s
their - characteristic
shapes.
Metaphase-11.
Early
a regular
division
Fig.
L a t e anaphase
to each
t h e -chromosomes
y
F i g . - 23.
24.
-
of the four
anaphase
has
11, t h e chromosomes i n
taken
place.
1 1 , 12
chromosomes ^
poles.
Fig.
25.
Four n u c l e i r e s u l t
Fig.
26.
Tetrad
from
vision.
of p o l l e n
grains.
the second d i
-2611ate
1.
17
12
-27Plate
11.