Diversification of rice (Oryza sativa)-based cropping systems for higher productivity, resource-use efficiency and economics

A field experiment was conducted at Bhubaneshwar under irrigated medium land condition from 2002 to 2005 to evaluate the production potential, resource-use efficiency and economics of 10 cropping systems based on rice (Oryza sativa L.). Rice-groundnut-greengram system resulted in maximum number of effective tillers in rice (362/m2), longest panicles (23.0 cm) and maximum number of grainslpanicle (1 12). However, system pro- ductivity of rice-maize-cowpea was the maximum (15.98 tiha) which was on a par with that of rice-maize- greengram (15.30 tiha). Rice-sunflower-greengram registered the minimum rice equivalent yield (REY) of 11.66 t/ha among the three-crop sequences and rice-toria-fallow (8.36 tiha) among the two-crop sequences. Sustain- able yield index (0.85), production efficiency (50.73 kg REYIhalday), employment generation (550 man days/ha) and net returns (Rs 40,415lha) were maximum in rice-maize-cowpea followed by rice-maize-greengram system. Inclusion of two legumes improved the sustainability and that of groundnut increased the land-use efficiency of the systems. Returns per Re invested were the highest for rice-fieldpea-sesame system (Rs 1.94), which were on a par with that of rice-maize-cowpea and rice-maize-greengram systems (Rs 1.85 and 1.83 respectively). Crop- ping systems having maize as a component crop expressed higher production efficiency (Rs 124 to 128/ha/day), water-use efficiency (Rs 203 to 21 3/ha-cm) and energy intensiveness (1 1.23 to 12.56 MJ/Re) in economic terms. Rice-maize-cowpea was the most productive, sustainable, resource-use efficient and remunerative cropping system.