Systematic identification of genus Brachiaria on the basis of vegetative and floral morpho-palynological markers (LM & SEM)

The present study deals with the few taxonomic parameters of the 5 species of genus brachiaria carried out from pakistan as there is confusion in identification of these species particularly on the basis of morphology and palynology. in the context of morphology,characters such as spikelet differentiation,lemma and palea shape and size,spike color,shape and size,glumes length and width were found useful in the delimitation of taxa in the genus. the inflorescence morphology particularly the spikelet was examined in detail and found to be highly variable. all the available records are listed and mapped. the palynological analysis provides qualitative and quantitative systematic data. the results showed some distinct palynological features. variations in pollen characters like apertural form,exine ornamentation,pollen shape and size,polar and equatorial diameter and p/e ratio were observed. brachiaria villosa was given in the flora of pakistan and was considered to be of doubtful origin in pakistan by stewart (1990). this species is also confirmed to occur in pakistan in the present study. also there is no published data already regarding the morpho-palynological distinctions among the species of brachiaria particularly from pakistan.