Origin

Abstract

Rice belongs to a group of extremely ancient grasses and shows more genetic and morphological diversity than almost any other cultivated crop. Rice is basically a terrestrial plant adapted to an aquatic habitat. In general, it is less tolerant of drought stress than other cereals and when stressed it suffers more rapidly than other cereals (Moormann and Veldkamp, 1978). It is tropical and highly self-pollinated, and is regarded as a short-day plant, since in all wild forms and most traditional cultivars shorter days induce panicle initiation and thus largely determine the growth duration. Rice is a C3 plant. The genus name Oryza is derived from the Greek, meaning ‘of oriental region’. There are two major cultigens: sativa, Latin for ‘sown’, and glaberrima, Latin for ‘smooth’ and free of hairs.