Performance of intervarietal intercropping on rice (Oryza sativa) in summer

An experiment was conducted during 1996 and 1997 at Kalyani to study on gro wth, production potential, competition functions and economics of intervart ietal intercropping systems in transplanted summer rice (Oryza sativa L.). An intercropping of 'Jaya' + 'IR 36' rice at 4:2 planting ratio gave the ma ximum dry matter, highest number of tillers/m(2), matured panicles/m(2), fi lled grains/panicle and minium percentage of unfilled spikelets/panicle and resulted in the highest grain yield (6.24 tonnes/ha) per unit area and tim e which was 28.4 and 30.82% higher than sole 'Jaya' and 'IR 36' respectivel y. This system was also found to be advantageous compared with monocropping of respective component varieties, with the highest land-equivalent ratio (1.29), area-time equivalent ratio (1.23) and relative crowding coefficient (5.58) values. 'Jaya' + 'IR 36' at 4.2 row ratio proved to be the most rem unerative system with maximum net return (Rs 24,211), net production value (1.48), relative value total (1.28), relative net return (1.27) and monetar y advantage (7715.3) among the intercropping systems. Net returns accrued w ith sole 'Jaya', 'IR 36' and 'Pant 4' were increased significantly by Rs 8, 687, 8,964 and 7,979/ha owing to intercropping of 'Jaya and 'IR 36' at 4:2 row ratio respectively.