Colour
change
Malvaviscus
Gerhard
of
petals
arboreus
in
flowers
Gottsberger
Department of Botany, University
of
Nijmegen, Nijmegen, The
Netherlands*
SUMMARY
Colour
changes
in
the
of two varieties of the
petals
absorbance
investigated.
The
were
measured.
separation of pigments by
Older
stages
of
ones,
and also
wavelengths.
A
living petals
merely
a
by
at
515
show
at
440
which
nm
the main visitors of
Hummingbirds,
also
have
about
be due to
may
a
at
different
a
515
the
Malvaviscus, probably
attempted.
with
beginning
younger
towards
higher
spectrum;
producing
This loss is
pigments.
use
nm
absorption
while nectar
nm
with
520
petal-extracts
was
wavelengths compared
loss of red
and coincides
chromatography
paper
at
at all
of
chromatography
and the maximum
nm
Malvaviscus arboreus
and the absorbance
of paper
means
low absorbance
a
maximum
a
tropical plant species
living petals
Petal extracts of different stages
shoulder
monstrated
show
shift of the minimum
a
producing flowers
nectar
nectar
light
of
were
of nectar
non-
ones
have
clearly
de-
production.
this colour-shift for
recognizing
producing flowers.
INTRODUCTION
The purpose of the present
study
of the
two
cus
in
pigments
arboreus Cav.
scribed
as
of
petals
anthesis.
during
(Gottsberger
1967)
var.
final conclusions will be discussed
Malvaviscus arboreus
The
hummingbirds.
flower tube which
var.
scarlet
observed that
reach
cannot
tropical
flower visit
holes
only
glected
*
by
such
in
the
flowers
petals
from the
the
author
flowers
to
in Brazil. His
ecological
bird
to
start
Need.
into
back-
petals.
which
The
first
already
Departamento
de
Estado de Sao
20(4), August
region
deep
with
flower
boring
on
observation
are
Botanica.Faculdade
a
long
several
studied. It
tube,
but get
cutting by
flower
visits.
was
short
it
sub-
presented
Every
single
by simply counting bill-marks,
was
had started with
They
flower
form
relatively
or
long-tubed tropical
established
nectar.
was
for
specialized
During
nectar.
the flowers
via the
experiments
easily
was
a
of
amount
Sao Paulo
are
sympetalous
not
the corolla. This
through
younger flowers without
Present address:
large
legitimately
nectar
cuts
hummingbirds
a
a
though
hummingbirds visiting
opportunity
Botucatu, Botucatu,
Acta Bot.
the
short
short-billed
excellent
red
hummingbirds
only by making
visited
show
to
has flowers which
penduliflorus
its base contains
at
months the behaviour of
viz.
again briefly
region
de-
was
present
bird-visitors
on
Malvavis-
of this report.
ground
an
The
in the Sao Paulo
penduliflorus
composition
arboreus
var.
(1939:79).
has made extensive observations
of Malvaviscus arboreus
bills
arboreus
Porsch
by
in
change
tropical plant species
Malvaviscus
flower
hummingbird
a
the
investigate
to
was
varieties of the
that
certainly
de Ciencias
the
hummingbirds
production
nectar
not
able
Medicas
e
to
and
see
ne-
the
Biologicas
de
Paulo, Brasil.
1971
381
OOTTSBERGER
G.
in the
nectar
the
to
staminal column grows
flower.
choose the
However, this
nectar
staminal columns
On the other
or
-
producing
the
petal
anthesis
author
to
a
in
nectar
still
bear
always
until the
not
progressively
flower wilts
flower from
a
producing
was
without
effect;
bud
and
out
a
ones
stage onwards
this
able
probably
by observing
one
nec-
non-producing
from the
pointed
the consideration that the trained bird is
non-producing
bird
visited. The observation that
lighter
was
-
the
with cut-off
still discriminated.
were
flowers
the
as
nectar-
a
by
flowers
producing
less intense colour than
a
soon
recognize
can
characteristic used
only
Nectar
non-producing
a manner were
colour becomes
during
the
not
production starts,
nectar
of the flower tube. As
otherwise modified appearance
an
hand, placing
flowers
is
flowers.
containing
flowers treated in such
tar
When the
out
staminal column becomes visible the birds
stigma plus
producing
flowers.
pendent, long-tubed
stigma plus
the
brought
distinguish
to
difference in the
colour intensity.
The
effect
whether the
question
(the petals
difference in
slight
continuously)
grow
or
the
ments
themselves remained unanswered up till
tion
first contribution is related
a
change
a
of Malvaviscus arboreus
provisional
MATERIAL
Flowers of
var.
AND
phenomenon
how
flowerbirds
sharply
varieties of Malvaviscus arboreus
two
a
dilution
pig-
of flower-colour
anthesis and the author has
during
question
is
intensity
modification of the
In the present communica-
now.
the
concerning
a
tried
give
to
discriminate.
can
METHODS
cultivated in Sao
plants
from
penduliflorus
arboreus
the
answer to
colour
result of
obtained from
the
Botanical
studied; dried flowers of
were
and fresh flowers of
Paulo,
Gardens
Haren,
at
Netherlands,
var.
and
Mainz, Germany.
The absorbance of
light
fresh Malvaviscus arboreus
Lomb
Spectrophotometer,
attachment. Four
with
nectar
pieces
The
of the
petals
stage (called
weighed
of
bud)
was
mm
of
during
a
pigments
chromatography
attempted.
and
flower 3
obtained
nectar
Flower
starting
by always
several hours
several times
var.
model
of the
nm
of
Bausch &
1
just starting
wither,
to
and
measuring petal
550
were
of
nectar
yet
(called
producing
flower)
containing
were
0.01
%
sufficient extraction. The
bath.
diluted and the absorbance
nm was
measured with
a
Bausch
505.
of both varieties
analysis
extracts
give
were
Spectronic
petals
subsequent
The concentrated
to
on a water
to
not
ones
with methanol
penduliflorus
range of 250
a
producing
and concentrated
wavelength
600
a
20 with colour analyzer reflectance
anthesis;
were
to
measured with
investigated:
were
of both varieties in
renewed
of flowers of
was
diam.)
already
Spectrophotometer,
The different
results
flowers
centrifuged
extracts
of light within
382
and
and extracted
extracts were
& Lomb
(8
young
HCI. The solvent
The
size
same
petals
Spectronic
stages
flower 2in full
Comparable
range from 380
wavelength
a
arboreus
model
subsequent
production;
flower 4 wilted.
within
var.
the
applied
were
separated by
separated
as
small spots
Acta Bot. Neerl.
paper
compounds
to
was
sheets
20(4), August
of
1971
COLOUR
CHANGE
Graph
1:
OF
MALVAVISCUS ARBOREUS
Malvaviscus arboreus
600 nm of four
carefully
var.
arboreus.
subsequent stages
Absorbance
of living
washed Whatman No 3MM paper
Schweppe
1959:112),
of
means
separation
ascending
and
according
cut
in the alcoholic
quently developed
by
IN
PETALS
of
phase
absence of the determined
draw
to
us
Tsherwood and Hanes,
and subse-
(1959:14, fig. 13)
method gave
conclusions
at
range of 380 to
n-butanol/acetic acid/water (4:1:5)
This
some
petal pigments
wavelength
a
(method by
Linskens
to
chromatography.
enabled
within
petals.
sufficiently good
about the
presence
or
the different stages of anthesis.
RESULTS
The
light
reus
var.
young
absorbance of
flowers have
a
younger stages
a
slight
at
about 440
shift of the
is
higher wavelengths
and
a
light
maximum
the colour
at
nm.
intensity changes,
but that the
processes
observed in flowers of
ence
anthesis.
results
and
petals
be-
nm.
do
a
minimum
470
at
not
nm
only
of pigments themselves is
necessarily
not
where
of absorbance of different flower
stages may be
In older
of absorbance towards
be concluded that
can
penduliflorus
var.
about 520
has
already
composition
The
that
nm
reflect the
(presumably)
even more
a
differ-
than in
striking
arboreus.
var.
Graph
nectar
the
during
at
maximum
From these results it
modified
diminishes. The
and the maximum
minimum and
probably
instructively
of about 520
wavelength
The minimum of absorbance lies in
The oldest stage
seen.
540
nm
a
gradually
anthesis.
of Malvaviscus arbo-
stages
I. It demonstrates
at
absorbance
progressively lighter during
stages
subsequent
graph
strong absorbance
that in older flowers the
come
of the 4
petals
arboreus flowers is shown in
2 shows
producing
nectar
the absorbance of
states
petal
extracts
production starts)
and of
a nectar
position
tracts
absorption
Acta
of the
contain
a
spectra
Bot. Neerl.
maxima and
mixture
in
20(4), August
1971
penduliflorus,
of
just
at
about the
same wave
non-
before
Both
lengths.
minima of absorbance indicates that the
of flavonoid
general
var.
Bo=older bud,
producing stage (F=flower).
and F) show their maxima and minima
stages (B
The
of
(B=bud, By=young bud,
show
a
pigments.
We
maximum
at
know
that
270-280
nm
ex-
anthocyanin
and another
383
G.
Absorbance
within
of 250 to
and
at
one
of
about
at
one
the
ducing
suggested
latively
flowers
nm
one
flavones
region
according
in
of red
comparison
the
whereas the
nectar
at
producing
to
the
515
amount
(1955:
nm
flower
full
have
shows
than the
(F).
regions
two
and another
nm
However,
have
of
nectar
with the
pro-
flowers,
The results
decreased
nectar
This
only
bud stage
young
strong decrease
re-
drop
production.
shows
(Bo)
non-
nectar
older
dilution effect.
beginning
a
range
stages (B)
anthesis
yellow compounds.
compared
(F)
of bud
var.
petal-
wavelength
486-488).
compounds
of
of
demonstrates that the
nearly produces
nm
flower in
flavonols
slight
coincide with the
seems to
a
nm
have also diminished in older
anthocyanin
with the
flower which
decreased maximum
515
at
550
about 240-260
anthocyanins
due
probably
amount
pigments
is notable that
more
and
at
Geissman
to
yellow compounds
which is
less,
that the
more
contain
(B)
The
(F).
in red flower
slightly
yellow
of B and the “shoulder” of F
ones
but much
the
nm;
absorption,
about 330-375
“peak”
producing
It
520
high-intensity
a
arboreus
Malvaviscus
Graph 2:
pendulifloris.
extracts
GOTTSBERGER
at
a
(By)
this maxi-
mum.
The colour
compounds
Chromatograms
ones
main
(F)
of
separated by
producing
of Malvaviscus arboreus
compounds
flowers.
values 0.40 and
0.44)
In
have
The young flowers
clearly
var.
(B)
nectar
means
flowers
of paper
and
(B)
penduliflorus
distinguishable (some
are
non-producing
nine
were
non-nectar
producing
shown
are
under U.V.
flowers
chromatography.
nectar
in
light)
two
red
in
pletely absent,
of Malvaviscus arboreus
pigment
384
contain even fewer
the red
No 7we find
compound
a
Six
of the
compounds
(Up-
completely disappeared.
distinguishable compounds
(F3)
3.
extracts
arboreus
var.
{table 2).
In
later,
{graph 4)
nectar
stages (FI and F2), the lilac compound No 5 has nearly disappeared.
ered flowers
producing
graph
bluish
one
compounds: Compound
No 3 is also
with
a
lacking
slightly
No 5 is
Old,
with-
now
com-
and instead of the
lower R
show
producing
yellow
value.
F
Acta Bot.
Neerl.
20(4), August
1971
COLOUR
CHANGE
OF
Malvaviscus
Graph 3:
bud
at
thus
same
the
subject
1.
are
a
var.
at
petal
extracts
of
%
HC1.
nm
it
two
failed. The
off from the
By measuring
was
the absorbance
found that the
pigments
with the
and identificationof the
bands of
chromatogram
compounds
same or
pigments
nearly
may be
future study.
arboreus
var.
colour and R F values in
order of appearance in flower
extracts
of
penduliflorus.
Pigment
Pigment
1
violet
Pigment
2
red
Pigment
3
red
Pigment
4
bluish
Pigment
5
yellow
Pigment
6
light
Bot. Neerl.
cut
were
least
separation
Pigments
Acta
0.01
of
(F).
separated pigments
arboreus
still mixtures of
Pigments, pigment
Malvaviscus
anthesis
between 250 and 550
RF value. A further
of
pendulifloras. Paper chromatograms
methanol containing
separated
ARBOREUS
identification of the
wavelengths
the
Table
var.
and flowers in full
No 2 and No 4 of
and diluted in
the
MALVAVISCUS
arboreus
stages (B)
An attempt
pigment
at
PETALS IN
20(4), August
1971
colour
(UV)
R
f
value
0.23
0.40
0.44
(UV)
blue
0.51
0.88
(UV)
0.98
385
G.
Graph 4:
Malvaviscus
stages (B),
Table
2.
arboreus
flowers in
Pigments, pigment
var.
full
arboreus.
anthesis
R
colour and
Malvaviscus arboreus
var.
F
Paper chromatograms
(FI, F2)
values in
of
and withered flowers
petal
OOTTSBERGER
extracts
order of appearance in
flower-extracts
Pigment colour
R
f
value
Pigment
1
violet
Pigment
2
red
0.36
Pigment
3
red
0.40
Pigment
4
red
0.43
Pigment
5
lilac
Pigment
6
blue
0.23
(UV)
0.53
(UV)
0.74
yellow (UV)
0.84
0.90
Pigment
8
blue
Pigment
9
light
386
of
arboreus.
Pigments
Pigment 7
of bud
(F3).
(UV)
blue
0.97
(UV)
Acta Bot.
Neerl.
20(4), August
1971
COLOUR
CHANGE
OF
PETALS IN
MALVAVISCUS
ARBOREUS
DISCUSSION
A colour
soluble
in flowers,
change
is
pigments,
marized
our
in 1954. The colour
knowledge
(1950)
colour differences
1960
and his
etc.)
quite
(1941a,
the
still
are
thought
be similar
extra-tropical
& Grant
(Grant
signals
the
to
few
that their eyes
and much
van
colour
investigated
in
change
them flowers
look
at
quite
the
petals
compounds
beginning
of
be
nectar
vision
violet,
which
(1915,
not
are
about
as
yet
important
quickly
easily recognizable
brief
as
in
a
time
as
indicate
general
sensitive
should be
yellow,
to
Faegri
too, which has
able
detect
to
a
than the human eye. For
readily
in the
which is
birds,
(Knoll 1956:139,
with
very
attracted
migrate
in
nectar
others)
even
are
more
only
of birds
they
starting
are
even
for flowerbirds
true
more
disappearing
are
vision of
general
then
much
of Malvaviscus arboreus
distinct from others
anthocyanin
that flowerbirds
flowerbirds
blue and
yet in this respect,
the red of
subtle
even
Frisch
discriminate
There red flowers
Should this
1966:110).
Pul
der
been
the
to
about the
to
von
Winkel 1969, and
to
red than the human eye
to
locate
to
the younger and
and others.
locate flowers rich in
sensitive
sensitive
sum-
1952, etc.)
insects
distinguish
Red flowers may be
1967b).
investigations
less
are
more
to
and
the work of
by
1941b),
which
through
bird
see
(1936,
neglect
can
water-
has
purely physio-
a
enables
(Poley 1968,
due
man.
1966,1967a,
migrating
The
possible.
that of
regions,
they
to
open. We know
bright colours, probably
&
Seybold
probably
change
of flowerbirds
ability
by showy,
not
is
of
change
to a
plants.
(1947, 1950, 1951a, 1951b, 1966, 1970),
Kugler
for flowerbirds
are rare
to
ability
well informed
school,
questions regarding
to
that
so
their
Schremmer
small colour differences
in
in
change
colour
a
immediately,
we are
(1921-1926),
Similar studies
and
such
About insects and
ones.
Knoll
that
proved
flowers in full anthesis
1953,
due
leaves,
phenomenon
effect and reflects the actual stage of the cells. Kugler
logical
and Vogel
older
and
fruits, seeds,
well-known
a
nectar
production
In
producing.
of the
petals
var.
fact,
should
two
red
penduliflorus
production.
ACKNOWLEDGEMENTS
This
investigation
Nijmegen
Linskens
M.
in the
out
carried
who
Prof. Dr.
corrected
St.
Vogel,
during
hospitality
my
at the Botanical
stay
a
I would like
and his staff for their
Barendse
Haren,
was
Netherlands.
to thank
and
English.
My
Mainz and my
Prof.
Dr.
Laboratory
L.
van
helpful discussions,
thanks
wife
Use
also
to
and in
Dr.
Gottsberger,
der
J.
of the
Fiji,
University
Prof.
particular
van
for the
Borssum
supply
Dr.
H. F.
Dr. G. W.
Waalkes,
of flowers
of
Malvaviscus.
REFERENCES
Faegri,
K.
London
Frisch,
& L.
van
der
Pul
(1966):
The
principles ofpollination ecology. Pergamon Press,
1966.
K. von
(1915):
Der Farbensinn
und Formensinn
der Biene.
Zool. Jahrb.
physiol.
Abt.
35:1-182.
—
—
(1953) :
Aus dem Leben
(1960): Ober
Press,
Acta
der Bienen.
den Farbensinn
Springer-Verlag, Berlin.
der Insekten.
Mechanism
of
colour
discrimination.
Pergamon
London.
Bot. Neerl.
20(4), August
1971
387
G.
T. A.
Geissman,
(1955): Anthocyanins, chalcones,
In:
plant pigments.
498.
Österr.
Grant,
G.
bot. Z.
&
V.
American
Modern methods
Tracey,
3: 450-
ofplant analysis
Fr.
Aliso
6:
Grant
Biologie
(1967b)
und
—
(1947):
Hummeln
—
(1950):
Der
brasilianischen
Malvaceen.
of
hummingbird pollination
Effects of
in
the
western
6: 51-66.
the western
American flora. II. Additional
hummingbird migration
und
Blumen.
I.-VI. Abhandl.
der
plant spéciation
zool. bol. Ges.
Saftmalsumfarbung
Ber. deutsch. bot.
und die UV-Reflexion
der
on
in
Wien
12.
Springer-Verlag, Berlin.
Ausnutzung
Hummeln.
Bliitenbesuch
Aliso
plant species.
21 :457-465.
Insekten
der Bliite.
Die
(1936):
an
103-105.
flora. Evolution
(1921-1926):
durch Bienen
Records
(1966):
of hummingbird pollinationin
& V.
Die
H.
Kugler,
Bliitenbiologische Beobachtungen
349-378.
Grant
records.
K. A.
(1956):
A.
K.
the California
—
& M. V.
flora. I. Some California
California
Grant,
(1967):
114:
Records
(1967a):
Knoll,
K.
Springer-Verlag, Berlin.
Gottsberger,
—
Paech,
GOTTSBERGER
aurones, flavones and related water-soluble
an
bei
den
Rosskastanienbliiten
Ges. 54: 394-400.
Kronblattern.
Naturwiss.
Schlammfliege(Eristalomyxa tenax).
34: 315
Zeitschr.
vergl. Physiol.
32:328-347.
—
(1951a): Blütenfârbung
und
Insektenbeslaubung.
Ber.
physikal.-med.
Ges.
Wiirzburg
66:
28-41.
—
(1951b): Blütenökologische Untersuchungen
mit
Ber.
Goldfliegen (Lucilien).
deutsch.bot.
Ges. 64: 327-341.
—
Die
(1952):
spontane
sekten. Festschr.
—
—
UV-Male
(1966):
2.
H. F.
Ed.:
D,
Poley,
me
(1959);
12-24.
O.
Bonner zool.
Das
(1939):
F.
Schremmer,
(1941):
H.
Botanik.
57-70.
In: H. F.
Linskens, Papierchromatographiein
der Botanik.
Berlin.
Beilr.
zur
Nahrungssuche
und
Nahrungsaufnah-
19: 111-156.
Bestâubungsleben
der
Kakteenbliite.
Blumenbesuch
System. Ökologie, Geogr.
zum
Nachweis
(1959): Organische
2. Ed.:
A.
In-
Verlag, Stuttgart.
(1941): Sinnesphysiologie und
Versuche
Schweppe,
bliitensuchende
1-10.
In:
Caclaceae,
Jahrb.
deutsch.
1-142.
Zool. Jahrb. Abt.
und
Techniken.
Fischer
durch
Farbqualitaten
(1968): ExperimentelleUntersuchungen
Kakteen-Ges.:
Seybold,
bestimmter
Nalurf. Schweinfurt:
Ber. deutsch. hot. Ges. 79:
Ed. 2. G.
Springer-Verlag,
der Kolibris.
Porsch,
Akad.
auf Bliiten.
(1970): BHitenökologie.
Linskens,
—
Bevorzugung
Griindung
110-134.
der Rotblindheit
Sàuren.
von
Plusia
gamma L.
In:
H.
von
F.
Vespa
rufa
L. Z.
vergl. Physiol.
28.
der
Linskens, Papierchromatographie in
Springer-Verlag, Berlin.
(1954): Untersuchungen
Samenschalen.
des Falters
74.
Sitzungsber.
iiber den Farbwechsel
Heidelb.
Akad.
Wiss.
von
Blumenblâttern,
Mathem.-naturw.
Friichten
Klasse
Abh.
2:
,
31-96.
Vogel,
St.
Winkel,
(1950): Farbwechsel
W.
(1969);
Funktionskreis
der
konzentrationen.
388
und
Zeichnungsmuster
Experimentelle
Nahrungssuche: Über
Z.
TierpsychoL
bei
Untersuchungen
die
Bliiten.
an
Bedeutung
Österr.
bot. Z. 97:44-100.
Zuckervögeln
von
Farben,
(Coerebidae)
Formen und
im
Zucker-
26: 573-608.
Acta Bot.
Neerl.
20(4J, August
1971