Influence of diversification on productivity, profitability and efficiency of rice (Oryza sativa)-based cropping systems under irrigated condition

A long-term field experiment was conducted during 2006–07 to 2012–13 at Bhubaneswar, Odisha under irri-gated medium land condition, to evaluate the production potential and economics of 10 rice (Oryza sativa L.)based cropping systems. Rice-tomato (Solanum lycopersicum L.)-cowpea [Vigna unguiculata (L.) Walp.] and rice-maize (Zea mays L.)-okra [Abelmoschus esculentus (L.) Moench] cropping systems recorded significantly higher rice-equivalent yield (24.24 and 22.75 t/ha respectively) than other systems evaluated, the relative production efficiency being 140 and 122% over the existing rice-groundnut (Arachis hypogaea L.) system. The rice-groundnut system recorded the least rice-equivalent yield (9.75 t/ha). Land-use efficiency (LUE) of rice-tomato-cowpea system was the highest (85.8%), followed by that of rice-groundnut-cucumber (Cucumis sativus L.) (83.8%) and rice-French bean (Phaseolus vulgaris L.)-sesame (Sesamum indicum L.) (81.9%). Rice-tomato-cowpea gave the highest gross and net returns of 277, 276 and 166, 776/ha respectively, followed by rice-maize-okra system with gross and net returns of 256, 210 and 150, 210/ha respectively. These two systems also recorded higher benefit: cost ratio (2.51 and 2.42) with 257 and 222% relative economic efficiency over the rice-groundnut system. The cropping systems which included the legumes like groundnut, cowpea and French bean improved soil organic carbon content by 15.9 to 21.7% over the initial value of 0.69%. The cropping systems having cowpea as a summer crop increased the available N content by 8.5 to 13.8%; however, the available P and K content in soil decreased in all the systems after completion of 7 cropping cycles, though the depletion in K was more pronounced than that of P.