Integrated assessment of diversification of rice-wheat cropping system in Indo-Gangetic plain

Diversification of rice-wheat cropping system may improve the productivity and sustainability of agricultural production in the Indo-Gangetic plane region (IGPR), but the choice of alternative sequences to be used requires integrated assessment of various crop sequences. A long-term field experiment was initiated during 2000-01 on sandy loam soil at Banaras Hindu University, Varanasi, India to assess 10 rice-based cropping sequences -rice-wheat, rice-chickpea, ricewheat- green gram, rice-wheat-Sesbania (green manure), rice-mustard-green gram, rice-lentil-cowpea (fodder), rice-pea, rice-lentil + mustard (3: 1)-cowpea (fodder), rice-maize (cob) _ vegetable pea (1: 1)-cowpea (fodder) and rice-potato-green gram in randomized block design with four replications. The data contained in this paper are for the year 2002-03 and 2003-04. Substitution of rice-wheat with 300% intensity cropping sequences particularly with rice-potato-green gram resulted in maximum production cost but gave the highest system productivity, net return, benefit: cost ratio, production efficiency, profitability and energy productivity. Inclusion of summer grain/ fodder legume or Sesbania for green manuring improved the content of soil organic matter. The soil P status was positively affected in all the sequences and particularly those with summer crops. Decline in soil available K in all the sequences indicated inadequacy of present recommended rate of fertilizer K to all the component crops in different sequences.