PRODUCTION POTENTIAL AND ENERGY-USE EFFICIENCY OF RICE (ORYZA SATIVA)-BASED CROPPING SYSTEMS

A field experiment was conducted during 1986-88 at Madurai with 5 diff erent rice (Oryza sativa L.)-based cropping systems, 2 fertilizer leve ls and 2 irrigation regimes. The production potential in terms of rice -yield equivalent was more in groundnut (Arachis hypogaea L.) + blackg ram (Phaseolus mungo L.) - rice - sesame (Sesamum indicum L.) sequence . Irrigating the rice crop to 5 cm depth on the day of disappearance o f ponded water and irrigating the rainy-season and summer crops at 0.7 5 and 0.60 irrigation water depth cumulative pan evaporation (IW : CPE ) ratios respectively gave highest rice-grain yield equivalence. Recom mended level of irrigation and fertilizer NPK based on soil test enabl ed higher utilization of solar energy.