Effect of agronomic management practices on the performance of rabi summer groundnut (Arachis hypogaea) under rice (Oryza sativa)-groundnut cropping system

Land after rice cultivation is left as fallow which can be utilized for cultivation of groundnut as this can curb down the current import of vegetable oils to a significant level which falls heavy on the Indian economy. Still, proper combination of nutrient management and seed treatment practices are required to enhance the productivity of groundnut under rice - groundnut cropping system. In this regard, a field experiment was conducted during rabi summer season of 2017 to 2019 at Oilseeds Research Station, Tindivanam, Tamil Nadu, India to study the effect of agronomic management practices on rabi summer groundnut under rice - groundnut cropping system. In this experiment, two varieties viz., TMV 7 and TMV13 were tested along with various nutrient management practises viz., 75% recommended dose of fertilizer (RDF); 100% RDF; 125% RDF; 75% RDF + Rhizobium (seed treatment); 100% RDF + Rhizobium and 25% RDF + Rhizobium. The result indicated that, among the two tested groundnut varieties, TMV 13 seed treated with Rhizobium along with 100% RDF recorded higher plant height (40.3 cm), number of branches (8.8), pods/plant (21.8) and pod yield (2395 kg/ha) over other treatment combinations. It could be concluded that cultivation of groundnut var. TMV 13 under rice fallow areas is economical with higher benefit: cost ratio (3.30) when fertilized with 100% RDF (25:50:75 NPK kg/ha) and seed treated with Rhizobium @ 600g/ha to lay a foundation for effective rice - groundnut cropping system.