Diversification of rice (Oryza sativa L.)-based cropping systems for higher productivity, resource-use efficiency and economic returns in south Gujarat, India

The continuous growing of rice has led to a deterioration in soil quality, resulting in a serious threat to agricultural sustainability in the high rainfall zone of south Gujarat, India. Therefore, crop diversification with a wider choice in the production of crop varieties is being promoted to restore the soil quality. A field experiment was conducted in Navsari, India during 2003-2007 on a Vertisol to evaluate the productivity, sustainability, resource-use efficiency and economics of 10 rice-based cropping systems. The results showed that system productivity for rice-fenugreek (Trigonella foenum-graecum)-okra (Abelmoschus esculentus) was highest (25.73 t ha(-1)), followed by rice onion (Allium cepa) cowpea (Vigna sinensis L.) (24.15 t ha(-1)); and the lowest system productivity was observed with the rice-wheat (Triticum aestivum)-fallow system (7.85 t ha(-1)). The sustainable yield index (0.97), production efficiency (102.94 kg ha(-1) day(-1)) and field water use efficiency (15.98 kg ha(-1) mm(-1)) were maximum with the rice-fenugreek-okra system. Similarly, net return (96,286 Rs ha(-1)), net return per rupee invested (2.83 Rs), monetary production efficiency (385.14 Rs ha(-1) day(-1)) and water use efficiency (59.80 Rs ha(-1) mm(-1)) were maximum with the rice-fenugreek-okra cropping sequence. There were significant effects of various cropping sequences on available nitrogen, phosphorus, potassium and organic carbon content in the soil. Overall, the rice-fenugreek-okra system was found to be the most productive, sustainable, resource-use efficient and remunerative cropping system, followed by the rice-onion-cowpea system.