TAXONOMIC RELATIONSHIP OF THE GENUS DIGITARIA
SYED SHAHINSHAH GILANI*, MIR AJAB KHAN**, ZABTA
KHAN SHINWARI***, FARRUKH HUSSAIN AND ZUBAIDA YOUSAF**
Abstract: Numerical techniques were used
to show the taxonomic relationship between the Digitaria species in Pakistan.
A correlation phenogram showed a distinct dissimilarity between the species.
Digitaria sanguinalis possesses a distinct morphological character of having
silicious spines on lateral nerves of lower lemma. New additions of subspecies
to D. sanguinalis in Pakistan are reported as D. sanguinalis ssp.
pectiniformis, D. sanguinalis ssp. aegyptiaca, D. sanguinalis
ssp. vulgaris (varieties glabra, rottleriana and pubescens)
and a new subspecies D. sanguinalis ssp. pakistanica with two new
varieties such as D. sanguinalis ssp. pakistanica Gilani, Khan and
Shinwari var. pakistanica Gilani, Khan and Shinwari and D.
sanguinalis ssp. pakistanica var. stewartii Gilani, Khan and
Shinwari, which gave same results by numerical analysis. They were clustered
together confirming the current findings. The independent status of D.
denudata Henr., from the D. stricta which was considered by most of
the taxonomists as D. stricta var. denudata was confirmed. Similarly, the
controversial taxa viz., D. ciliaris (Retz.) Koel., and D. bicornis
Roem. & Schult., have to be considered distinct species which is supported
by the minute morphological characters i.e., ciliated frill around the margins
of the lower lemma of the spikelets, shorter distance to the first lateral nerve
on the lower lemma, a longer upper glume and a shorter lower glume as compared
to D. ciliaris. D. cruciata (Nees) A. Camus was also a new
addition to the flora of Pakistan. It may have differed from all other related
species by its broad and turgid spikelet and the large ovate upper glume, with
three nerves that never reach to its apex. This character was neglected and the
species was not added to the Flora of Pakistan. Cluster analysis also confirmed
the morphological findings that it was not the variant of D. ciliaris but
a distinct species. D. stewartiana Bor, an endemic to Azad Kashmir,
was not classified at section level by any of the taxonomists. It differs from
its related species, D. ischaemum (Schreb.) Schreb. ex Muhl. and D.
violascens Link, was more closely related to the D. ischaemum than
D. violascens. It clustered with D. ischaemum. Thus it is suggested
that it may be transferred to section Clavipilae and placed with D. ischaemum.
Centre of Biotechnology,
University of Peshawar, Peshawar, Pakistan.
Department of Biological Sciences, Quaid-I-Azam University, Islamabad, Pakistan.
COMSTECH, Islamabad, Pakistan.
Corresponding Author: email@example.com