Effect of dual cropping of green manure

Rice is one of the most important food grains produced and consumed all over the world. It is the major staple food for more than two billion people in Asia and one third of the calorific intake of nearly one billion people of Africa and Latin America. Hence rice can be rightly called as ''The stuff of life''. Worldwide rice is cultivated in an area of 153.8 m ha which is more than 10 per cent of the arable land.Rice is adapted to various edaphic and climatic conditions. Rice is being cultivated from below sea level in Kuttanad of Kerala to higher altitudes as in Jammu and Kashmir revealing the heterogeneity of its environment and its different modes of cultivation. The semidry rice cultivation is prevalent in twenty per cent of rice area of our country with low productivity of one t ha-1 when compared with the normal productivity of transplanted rice of about 5 t ha-1 (TNAU Annual report 2000). In Tamil Nadu semidry rice system is practiced in about one lakh hectares with a mean productivity of one t ha-1. Thus there is an imminent need to raise the level of productivity to narrow down the wide disparity.