Morphofunctional Diversity of Diaspores of Some Range Grasses of Punjab (India)

Grasslands occupy almost half of the terrestrial expanse of India ranging from coastal to alpine regions. Whyte (1958) defined ‘grassland as the land on which graminaceous species represent the dominance if not the exclusive vegetation’. Grasslands comprise the main source of fodder for the 500 million cattle population in the country besides providing habitat to several plant and animal species. But the grasslands are shrinking due to the pressure of intensive agriculture and urbanization not only in expanse but also in their biodiversity. In this context there is an urgent need to develop not only a policy towards a sustainable utilization of grassland resources but also to devise strategies to replenish and refurbish their productivity and biodiversity. Grasses have an unmatched ecological significance as well. They occur in nearly all the terrestrial ecosystems and habitats of the world and provide cover to nearly a fifth of the land surface. Taxonomic diversification and geographic diversification occurred during the Eocene in several phases beginning with the crown node of bambusoid grasses (53mya) and continuing with the pooid (47-38 mya), chloridoid (35-25mya) and panicoid (26mya) groups (Kellogg, 2001). With their origin in the southern land masses, grasses are believed to have spread to Eurasia via the Indian land mass