PALYNOLOGICAL EVIDENCE SUPPORTING THE IDENTITY OF TWO TAXA OF BERBERIS (BERBERIDACEAE) FROM TIBET

4 Pages·1997·2.3 MB·English

by  Arti Garg

PALYNOLOGICAL EVIDENCE SUPPORTING
TWO
THE TAXA
IDENTITY OF OF BERBERIS
FROM
(BERBERIDACEAE) TIBET
RAO
ARTI GARG, TARIQ HUSAIN,
and R.R.
and
Taxonomy
Division
Biodiversity
National Botanical Research
Institute
Rana 226001
Pratap Marg, Lucknoiv
-
INDIA
U.R,
dentity oi Berber:s replicata var. dispar
of pollen morphology. Phylogeneci
s
an advanced
taxa.
iriffithiana
var. pallta
riffithiana
INTRODUCTION
In continuity of Husain et al. (1994) paper on The identity of two taxa of
W.W.
Sm.
Berberts Berberidaceae) from Tibet, the identity oiBerberts replicata
(
&
var. dispar Ahrendt and B. griffithiana Schneid. var. pallida (Hk.f. Th.)
—
& Hu
Chamberlain discussed the Hght of pollen morphological char-
in
is
acters using light and scanning electron microscope.
PolliniferoLis material for the present study was obtained in the form of
70%
dried flower buds from Herbarium sheets. The material was soaked in
alcohol for 48 hours and pollen was subsequently acetolysed according to
One
method Erdtman was
the of (1952). part of the acetolysed pollen
compound
mounted on glycerine and observed under micro-
slides in jelly
mounted
scope while the other part was on brass stub, gold coated, ob-
and photographed under scanning microscope.
served electron
AND
R ESULTS DISCUSSION
morphologic^d char acters of the three taxa (distribute
le
and Chin
ilaya lely B. replicata var. dispar (Indi
&
LWG),
Rana
Pradesh: Party 210335,
T. S. B. gnffithiana var. gnffithiana
& LWG)
(India: Arunachal Pradesh: Rana Party 210330, and B.
T. S.
&
BM)
gnffithiana v^t. pallida (China: Ludlow, Sheriff Taylor 5691, are tabu-
lated and a key for the seggregation of B. replicata and B. thiana are
griff
provided Husain communication. The morphology
in et pollen of
al. c.)
(/.
these taxa given in Table and explained as follows:
is 1
Berberis replicata dispar
var. (Figs. 2)
1,
2-3
Grains inaperturate, colpoid streaks occur in association with
ir-
pm
regular fissures on the exine surface. Exine 1.7 thick; ectoexine equal to
endoexine, columella with
indistinct; surface psilate, ill-defined irregular
pm
Grains spheroidal; diam 45 (44-47 pm); tectum
folds. ill-defined.
Berberis
griffithiana 3-6)
(Figs.
Grains spiraperturate, spiral twines irregulary dileneating the surface
into elongated and rounded aperture narrow, margin smooth. Exine
areas;
pm
thick, ectoexine thicker than the endoexine, columella
3 indistinct;
surface coarse, organised into irregular raised lumps of piloid elements or
pm
warted. Grains spheroidal, diam 34/40 (32-42 pm). Tectum
irregular.
Grains spheroidal; diam 34 pm; surface with closely packed, homogenous
1.
elements
piloid griffithiana
var.
Grains sub-spheroidal; 37 x 40 pm; surface warted pallida
1. var.
The
pollen grains of B. griffithiana var. griffithiana and B. griffithiana var.
pallida were found to be similar to each other but revealed considerable
differences with those of B. replicata var. dispar in primary (apertural), sec-
ondary (exine ornamentation) and tertiary (exine strata, shape and size)
characters (see Table This supports the view of Husain et that
1). al.
c.)
(/.
B. replicata var. dispar a distinct taxonomic entity and being closer to B.
is
replicata in macro-morphological characters, should be kept as a variety
under B. replicata and not be merged under B. griffithiana var. pallida.
Walker and Doyle
(1975) phylogenetically classified pollen with respect
number
to the of apertures Inaperturate mono-aperturate
as di-
(i) (ii) (iii)
aperturate (iv) tri-aperturate or (v) poly-aperturate with 4,5,6 apertures
and
aperture shape as elongate, furrow like round, pore like
(i) (ii) (iii)
band The
encircling ring or like. pollen grains of B. replicata var. dispar are
basically inaperturate, the primitive type whereas those of
B.
griffithiana
are spiraperturate (encircling the grain), the advanced type. Hence, B.
replicata is considered primitive and B. gnffithiana advanced. The two taxa
ng
elect
^BeZ
'^^^^
-2
replna
ts
rged
fold
6. Berber sgnffitf tana spiral. 5) surface with piloid elements
6)va poUe nwit
.palUda,
4)
giosperms. Almqvist and
two
of caxa of Berheris
/
phylogeny: Palynology.
1