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 possess 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 clustured 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.
Page(s):
261-278
DOI:
DOI not available
Published:
Journal: Pakistan Journal of Botany, Volume: 35, Issue: 3, Year: 2003