PERFORMANCE OF CASTOR (RICINUS-COMMUNIS) CULTIVARS AND THEIR RESPONSETO FERTILIZER AND PLANT-PROTECTION

An experiment was conducted during 1989-90 and 1990-91 to study perfor mance of castor (Ricinus communis L.) varieties and their response to fertilizer and plant-protection chemicals at Mandor. Castor hybrid 'GC H 4' showed superiority to 'Aruna' for 1 000-seed weight, oil content, and seed and oil productivity and less incidence of jassid (Empoasca flavescens Fabr.). The former gave additional oil yield (723 kg/ha) an d net return (Rs 6 609/ha) compared with the latter. Hybrid 'GCH 4' si gnificantly responded to fertilizer application in terms of seed and o il yields. However, the yield of 'Aruna' was at par under fertilized a nd unfertilized conditions. The 2 cultivars responded significantly to plant-protection sprays, recording higher seed and oil productivity a nd net return than their unprotected crop. Despite low jassid infestat ion in 'GCH 4' compared with 'Aruna'. both suffered similar loss in yi eld in unprotected plots.