Alternate system to rice (Oryza sativa) under Cauvery Command area of Karnataka

Abstract

A field experiment was conducted at the research farm of College of Agriculture, V.C. Farm, Mandya, Karnataka from 2017–18 to 2019–20 to study the efficient cropping system alternate to Rice (Oryza sativa L.) under Cauvery Command area of Karnataka for higher productivity and profitability. The experiment was laid out in Randomized Complete Block Design (RCBD) consisting of 12 crop sequences with 3 replications. Initial and final soil samples were collected and analyzed for soil pH (7.4), EC (0.15 dS/m), organic carbon (0.56%), N (130 kg/ha), P2O5 (17.2 kg/ha) and K2O (306.6 kg/ha). The EC and Organic carbon recorded after harvest Bhendi [Abelmoschus esculentus (L.) Moench]-Ragi [Eleusine coracana (L.) Gaertn.] and marigold (Tagetes spp.)-Blackgram [Vigna mungo (L.) Hepper] sequence was on par with Rice (Oryza sativa L.)-Rice system. However the highest organic carbon (%) was recorded in Cowpea [Vigna unguiculata (L.) Walp.]-Ragi + Cowpea. The highest available soil nitrogen (363.78 kg/ ha) and available soil P2O5 (63.66 kg/ha) was recorded in Blackgram-Groundnut (Arachis hypogaea L.) followed by Cowpea-Ragi + Cowpea and Marigold-Blackgram. Significantly higher available K2O (173.88 kg/ha) was recorded in Maize (Zea mays L.)-Greengram [Vigna radiata (L.) R. Wilczek] system. Among all the cropping sequences, Bhendi grown in rainy (kharif) season and Ragi in summer recorded appreciable Rice equivalent yield with higher B:C ratio. The highest water productivity (20.05 kg/ha-mm) was recorded in Marigold followed by Bhendi (16.75 kg/ha-mm), Ragi (11.44 kg/ha-mm) and Maize (8.11 kg/ha-mm). However, the sequence Cowpea in kharif followed by Ragi + Cowpea in summer also resulted better under rice production system.