Life-history
Bryopsis
studies
Life-histories
Lamx.
the
H.
in
the
in
European
hypnoides
Bryopsis
different
from
genus
IV.
(Chlorophyceae)
points
along
coasts
Rietema
Biologisch
Universiteit
afdeling Plantensystematiek,
centrum,
Haren
Groningen,
(Gr.)
SUMMARY
Zygotes
of
Bryopsis
which
germlings
directly developed
lected
the
in
Rade
from the Rade
1.
giant
the walls of the
de Brest and
Neumann
Congo
the
red
de Brest
of the
germlings
those
germlingphase.
of several other
gametes,
be
to
the
(1969a)
of the
The
grew into
germlings
of
Bryopsis
filamentous
from
Banyuls
hypnoides
col-
Bryopsis hypnoides collected
positively
stain
the wall
of
germlingphases
Bryopsis species
as
monoecious,
other half
are
of the
in
Bryopsis
Bryopsis hypnoides
uninucleate,
nuclei. Neumann
mation.
and Zinnecker
that meiosis
In
some
the present
other
each
containing
tifida,
dium
crinale,
European
depth
crispus,
and also
on
about 0.5
Acta Bot. Neerl.
20(3),
creeping
nucleus into
to
take
on
a
rise
1957). Zygotes
one
giant zygote
germling phase
after
number of smaller
large
place preceding gamete
the work of Schussnig
produce convincing caryological
coasts are
micro-
to
for-
(1932)
evidence
formation.
hypnoides
collected form
described.
METHODS
following
Pointe de
Ceramium
rocks;
Banyuls; September 1967;
cea;
Bryopsis hypnoides
Feldmann
life-histories of Bryopsis
July 1968;
Chondrus
also
from the
assumption
collected from the
Bryopsis hypnoides
Rade de Brest;
the
Bryopsis hypnoides
which each contained
giant
not
of
methods.
gametangium giving
place preceding gamete
the
paper
AND
sprouted
for he did
takes
places along
MATERIAL
germlings
he based this
(1935),
actually
a
assumed meiosis
(1969a)
Apparently
life-history
caryological
half of
division of the
(presumably mitotic)
as
macrogametes (see
to
thalli
Bryopsis
well
one
grew into diminutive creeping
nucleus. New
the
investigated
cultural
Helgoland, by
appeared
b.
and
than
Rade
Some
nucleus.
Recently
a.
zoids.
In culture
longer “dormancy”
a
and the
INTRODUCTION
from
2.
Banyuls
stephanokontic
de Brest. Zinc-chlor-iodine
phase and negatively
one
into
Bryopsis plants.
new
have
Banyuls
from
hypnoides
divided
upper
localities
Rostoviec;
investigated:
was
epiphytic
on
rubrum, Hypoglossum
sublittoral
Grotte du Troc;
Laurencia pinna-
woodwardii,
Geli-
zone.
epiphytic
on
Pterocladia
capilla-
m.
June
1971
291
H.
The life-histories of
Rade
de
Brest
locality
differed
from the first-mentioned
plants
two
from the second
plant
studied.
were
and of
locality
I
Banyuls (cf. fig.
at
one
from the
Bryopsis hypnoides plants
from those collected
slightly
RIETEMA
and
fig. 16).
For
methods of
isolation of
Rietema 1969 and 1970. If
culture
and under a
room
the Rade de Brest
in
phenol balsam, according
The
reactions
red
Congo
Banyuls
3.
of cell-walls of
vital
(a
and
stain)
light
in
kept
8 hours
-
a
see
1°C
16 ±
darkness).
stained with acetocarmine and embedded
Stosch
von
and
germlings
zinc-chlor-iodine
(1952).
thalli
mature
with
staining
to
investigated,
were
both
for
and Rade de Brest material.
Bryopsis
The
3.1.1.
1.7-2
similar
metes
male
derived
to
the
were
from
after about
high
cm
from the Rade de
hypnoides
original
in
were
nature.
were
also
produced
in
the
(fig. 4).
and also remained
germlings.
light
swarms
different
weeks
grew
of the
into
beginning
into
new
vegetative
gametangium,
was
subcultures.
female
constant
a constant
in
there
However,
gametangium produced
to
numbers
large
three months these
of
three months old
numerous
of the
one
female
feature
and the
day
about 6
were
conditions
germlings (30 observed)
zoids
stephanokontic
observation. After release
(fig. 7)
these
10 and
same
filamentous
creeping
germlings
Bryopsis hypnoides plants (fig. 9,
nuclei amounted
into
in such
a
a
that each
a
Bryopsis
nucleus
was
hypnoides
about 30
was
to
(8
mm
hours
started
to
within four
zoids
(fig.
8)
{fig.
12
II).
3-4.8a..
zoids
Cleavage
was
achieved
stephanokontic
of the
by
uninucleate
45 jx,
multinucleate thallus. In such
to
stephanokontic
way
of
germling phase
The diameterof such
the diameter of nuclei in
of the
292
3) ga-
of male and female gametes
production
in
(fig.
gametangia:
Caryological investigations
13).
phase
into
gametangium, respectively,
constant
produced
two
darkness)
contents
The filamentous
and
half of each
After transfer into fresh medium and short
directly
3.1.2.
upper
The
about
plants
morphologically
and female
(fig. 2)
of male and female gametes formed in
gametangia
16 hours
-
divide their
were
and this also remained
gametes (fig. 5)
After about
long (fig. 6).
into
grown
plants
subcultures.
Mixtures of
in
Male
in which the upper half of each
plants
and the lower half male
vegetative
These
determinate laterals transformed
in the upper and lower half of each
plant
(fig. I).
weeks
from
plants
produced
gametes
determinate laterals had
two
gametes in the lower half
one
Brest
life-history
Subcultures
or
were
RESULTS
3.1.
in
hours
the method of
to
for culture methods
cultures
derived from material collected in
Bryopsis hypnoides
caryologically
were
cultures and
otherwise,
long day regime (16
and thalli of
Germlings
unialgal
stated
not
a
eight
one
times
thallus the diameter
contents
of
divisions of the
zoid received
to ten
the
germling
giant
nucleus
nucleus. The diameter
Acta Bot.
Need.
20(3),
June
1971
LtFE-HISTORY
STUDIES
IN THE
GENUS
of these nuclei amounted
{fig.
14 and
3.1.3.
phase
about 10 [x.
Subcultures
derived
high
cm
similar
gically
germlings
from
to
original plants
the
directly developed
two
into
thalli
Bryopsis
how-
from
new
had
plants
thalli whereas
about
plants
morpholo-
were
Of about 55 six
nature.
Bryopsis
grown into
These
{fig. 16).
only
months old
germling
one
zoids after several months of observation. These zoids
produced stephanokontic
grew
by Congo
germlings,
Banyuls
weeks
two
germling
solutions.
determinate laterals
after about
and the
stained red and violet
The cell-walls of the
staining
from
hypnoides
Bryopsis phase
hypnoides
zinc-chlor-iodine, respectively.
Bryopsis
1.4-2.1
obscure
are
red
Congo
ever, remained uncoloured in both
3.2.
IV.
The details of this division
reactions of the cell-walls of the
zinc-chlor-iodide and
The cell-walls of the thalli of Bryopsis
red and
(CHLOROPHYCEAE)
15).
Staining
to
to
BRYOPSIS
similar
morphologically
to
the
original
from
plants
nature.
3.2.1.
phase
Staining
to
reaction of the cell-walls of the
zinc-chlor-iodine and
The cell-walls of the
Figs.
Fig.
stained
of
culture,
Male
2.
Fig.
3. Female
Fig.
4. Part of a
germling
the cell walls of the
a
red
Congo
germlings
were
reproduction
a
determinate
of Bryopsis
hypnoides
from the Rade
de Brest
from the Rade de Brest:
about two weeks
old
(grown,
in
lateral).
gametes.
gametes.
plant with gametangia;
gametes in
5.
stained red and violet in
solution, respectively,
Bryopsis hypnoides
from
Fig.
Fig.
and the
all.
at
1-15. Structure and
1. Habit
Bryopsis phase
red
gametophytic phase
and zinc-chlor-iodine
not
Congo
Part of
the lower half of each
plant with gametangia;
a
gametes in
the lower half of each
Fig.
6. Habit of
Fig.
7.
Stephanokonticspores shortly
Fig.
8.
Zoospore viewed
Fig.
9 and
a ca.
10. A
three months old
male
gametes
female
14.
half,
female
gametes
are
produced
in the
upper
half,
male
from above.
single giant nucleus.
Fig.
upper
germinatingstephanokontic zoid (three days old).
Germling with
13. Detail
the
germlingphase.
is still
12.
in
before release
the form of which
Fig.
produced
gametangium.
Fig. 11. A juvenile Bryopsis hypnoides plant 7 days
Fig.
are
gametangium.
of the
its
giant
Stephanokontic
after
germination of
a
stephanokontic
zoid
discernable.
nucleus
zoospores
(Acetocarmine- phenolbalsam).
before
release.
Each
spore
contains
one
nucleus
(Aceto-
carmine).
Fig.
Acta
15.
Spore-formation, showing
Bot. Neerl.
20(3),
June
1971
the
centrally placed nucleus.
293
H.
294
Acta Bot.
Need.
20(3),
RIETEMA
June
1971
LIFE-HISTORY
16. Habit
Fig.
ture
4.
STUDIES
of
Bryopsis
Bryopsis
zygotes
merous
the
hypnoides
These
of the
from
life-history
reproduced
fig.
that of
Banyuls
the
Banyuls
material is also
The cell-walls of the
sitive reaction
to
and
Banyuls
capable
from the
of
each of which
of
Bryopsis
hypnoides
material.
of
Furthermore,
sporophytic phase
show
tioned respects the
germlings
Bryopsis plumosa (Rietema
to
cut
1969,
1970)
new
sporo-
into
the
Rade
de
“dormancy”
of
de
new
Bryopsis
Brest)
of the
germling phase
into
nu-
plant.
Bryopsis
Brittany (Rade
the
produce
the
thalli.
show
hypnoides
a
po-
whereas the cell-walls of the
both
stains.
In all
behave like the
Bryopsis hypnoides
from
a
collected in
Bryopsis
Congo red,
reaction
negative
of
of
Brest
contents
“break” the
to
directly developing
gametophytic phase
de
germlings:
their
into
grows
of the material from
zinc-chlor-iodine and
a
dividing
17. It is much easier
capable
Rade
filamentous
creeping
are
gametophytic germling phase
than
in
(grown
DISCUSSION
germlings
in
old
lateral).
stephanokontic zoids,
diagram
Brest is
AND
IV.
about two weeks
hypnoides (Banyuls material)
that grow into diminutive
phytic phase.
(CHLOROPHYCEAE)
GENUS BRYOPSIS
from a determinate
CONCLUSIONS
Both
A
IN THE
Brittany (Roscoff)
above-men-
germlings
and
of
Banyuls,
respectively.
The
that
carried
investigations
the life-histories of
identical
at
way
far
out so
by
the present author
Bryopsis hypnoides
different latitudes
along
and
the
strongly
Bryopsis plumosa
European
coasts,
suggest
vary
in
roughly
an
as
follows:
Mediterranean
both form
in addition the
populations
culture
Acta Bot.
populations
stephanokontic
“dormancy”
of both
conditions,
Need.
20(3),
of both
zoids and
species
of the
have
only capable
June
1971
species
develop
have
new
germling phase
germling phases
of
forming
germling phases
that
Bryopsis plants directly,
is difficult
that
are,
stephanokontic
to
can
and
break; Breton
under the
zoids
present
and in
ad-
295
H. RIETEMA
Fig.
17.
days
determinate
of the
Diagram
dition the
of
life-history
laterals
grow
“dormancy”
Bryopsis hypnoides
out into
of the
Bryopsis plumosa (Rietema 1969)
also have
germling phases
into
a
backskil
(Swedish
West
fit into this overall
hypnoides
plumosa
have
and
ling phases
of
14
break. Zeeland popu-
to
of
“dormancy”
directly developing
is
easy
to
into
new
break after transfer
are
same
to
fig.
break
of
18. In all
with zinc-chlor-iodideand
negative
to
the
stains,
as
(Netherlands);
and
Bryopsis plants
life-history
in
Fiske-
of
Bryopsis
that of
Bryopsis
populations
type of life-history
is easy
new
(Baltic sea),
(Oslofjord) (Rietema unpublished)
from Zeeland
of the
reproduced
always
from Kiel
well. All these northern
the
from Helgoland
Bryopsis hypnoides
and Drobak
directly developing
diagram
on
the
and
the
“dormancy”
germling phase
never
forms
Bryopsis hypnoides
cases
stepha-
collected in
the cell-walls of Bryopsis
Congo red,
even
is
when
whereas the
germ-
they directly develop
Bryopsis plants.
histories of
296
Coast),
germling phase
positively
It remains
mosa
de Brest. Within
Bryopsis hypnoides (unpublished)
only capable
(1969a)
picture quite
northern latitudes is
new
and
Bryopsis hypnoides
Bryopsis hypnoides
nokontic zoids. A
stain
on
approximately
filamentous
only capable
plants
are
Neumann
by
the present author
by
of the
that
and in addition the
Rade
fresh medium.
Observations
and
is easy
germling phase
lations of
Bryopsis plants,
from the
of 1.7-2 cm.
plants
a
matter
of definition
Bryopsis hypnoides
from Zeeland
or
interpretation
whether
to
from northern latitudes and that of
(Netherlands)
monophasic
or
call
the
life-
Bryopsis plu-
biphasic heteromorphic.
Acta Bot. Need.
20(3),
June
1971
LIFE-HISTORY
Fig.
14
18.
of
Diagram
determinate
days
On
STUDIES IN THE
the
basis
the
GENUS BRYOPSIS
of
of
life-history
laterals
grow
as
to
interpret
Bryopsis
out into
hypnoides
plants
of 2.5-3.0
studies in the
comparative
northern and southern latitudes
tends
(CHOLOPHYCEAE)
along
the
the diminutive creeping
IV.
from
northern
latitudes.
life-histories of both
European
germlings
Within
cm.
coasts
the
species
at
present author
of the northern populations
separate sporophytic phases that have lost the capacity
to
form
stephanokon-
tic zoids.
observations
Caryological
noides collected in
single giant
(1969a)
on
nucleus.
the
on
the Rade de
the
germling phase
This observation
nucleus in
giant
the
unpublished).
ling (Rietema
the
into
meiosis takes
based this
opinion
for
he
There
are
(1932)
opinion.
Acta
zoids
stephanokontic
one
Bot. Need.
on
are
not
such
single giant
into
some
June
indications
1971
one
similar.
support
the
(e.g.,
caryological
the
According
(1935)
evidence
segregation
Bryopsis
opinion
and those
to
the formation of gametes. He
any
from
nucleus in each germ-
Bryopsis plants
fundamentally
produce
hyp-
only
Bryopsis hypnoides
the unconfirmed work of Zinnecker
did
20(3),
of
These observations also
place preceding
has
from Zeeland and Roscoff and
germling phases developing directly
(1969a)
nig
have
Banyuls alwasy
germling
is in accordance with that of Neumann
germling phase
Helgoland. Equally Bryopsis plumosa
monoica from
derived from Bryopsis
Brest showed that each
in the
to
that
dividing
Neumann
apparently
and Schuss-
support
offspring
of
his
one
297
H. RIETEMA
germling phase plant
into
meiosis takes
the
place
in
has in its
Bryopsis halymeniae
sporangia
life-history
producing stephanokontic
The site of meiosis has
lished).
in Derbesia marina it
the formation of
Dr. D.
R.
Kreger, working
has
cleaned cell walls of the
the Rade de
the
of these
skeletal
xylan
as
phase
after mild
of
of
with
dilute
chromatography
only
species.
unpub-
However,
place preceding
1969b).
Uni-
physically
According
in
cell
walls
ivory-nut
mannose
of the
acid
germling
yielded
mannan
his
to
contain
gametophytic phase
hydrochlorid
those of
to
Rietema,
1964;
Bryopsis hypnoides (collected
However, the
boiling
with
plant physiology (State
the cell walls of the
polysaccharide.
that
sporophytic phase
derived from it.
germling phase
patterns
interesting
diffraction patterns of
ray
gametophytic phase
corresponding
thin-layer
x-
is
that meiosis takes
department
made
it
for this
(Neumann
zoospores
recently
treatment
diffraction patterns
(Hustede
investigated
that
Bryopsis plumosa)
respect
Derbesia-like
a
caryologically
in the
and of the
Brest)
interpretations
By
shown
was
in
plants
In this
zoids
been
not
stephanokontic
versity, Groningen),
xylan.
male and female
germling phase.
x-
and
ray
not
to
detected in the acid
was
extract.
The chemical
composition
(probably
diploid) germling phase
significance
algae
green
of the
cell walls
differs also
haploid) phase apparently
as
of the
considerably
suggested
by
gametophytic
(probably
from that of the uninuclear
the
staining
reactions. The
of these observations in connection with the taxonomy of siphoneous
will be
discussed later.
ACKNOWLEDGEMENTS
The
the
author is much
manuscript.
fraction
I
indebted
wish
to Prof. C.
to record
my
den Hoek
van
to
indebtedness
for discussion
Dr.
Kreger
for
and critical
the
making
reading
of
dif-
x-ray
analyses.
REFERENCES
J.
Feldmann,
H.
Hustede,
Sur
(1957);
l’hermaphroditisme
du
Bryopsis hypnoides Lamouroux.
Bull. Soc.
Fr. 3: 7-8.
Phycol.
wechsel
(1964); Entwicklungsphysiologische Untersuchungen
zwischen
Derbesia
neglecta
Berth, und
iiber
halimeniae
Bryopsis
den
Generations-
Berth.
Bot.
mar.
6:
134-142.
Kylin,
H.
(1948):
Neumann,
K.
Die
hypnoides und
-
(1969b): Beitrag
Helgol.
Rietema,
—
Protonema
weitere
zur
(1969): A
new
Life-histories
mit
cytologische
Cytologie
Wiss. Meeresunters.
H.
(1970);
Chlorophyceen der
(1969a):
type
of
und
Schwedischen
Riesenkern
Befunde.
Westkiiste. Lunds
bei
Helgol.
Entwicklung
der
der
Univ.
Àrsskrift.
siphonalen Griinalge Bryopsis
\Viss. Meeresunters.
siphonalen Griinalge
19:45-57.
Derbesia marina.
19: 355-375.
of life-history
in Bryopsis.
Bryopsis plumosa
from
Acta Bot. Neerl.
European
coasts.
18 (5):
615-619.
Acta Bot. Neerl.
19:
(6)
859-866.
Schussnig,
B.
(1932):
bot. Zeitschr. 81
Stosch,
H.
A.
von
schlussmittel
Zinnecker,
bei
298
E.
:
für
Der Generations-
und
Phasenwechsel
bei
den
Chlorophyceen.
3.
Oest.
296-298.
(1952):
Die
Verwendung
Essigkarminprâparate.
von
Chloralhyd.at
Ziichter 22
:
(1935): Reductionsteilung, Kernphasenwechsel
Bryopsis plumosa (Huds.) Ag.
Oesterr.
oder Phenolbalsam
als Ein-
269-272.
und
Geschlechtibestimmung
Bot. Zeitschr. 84: 53-72.
Acta
Bot. Neerl.
20(3),
June
1971