摘要 : Studies were carried out in Bhubaneswar, Orissa, India, during summer 2002-03 and kharif 2003 to assess the effect of rice cultivars and plant nutrients on the efficacy of an insecticide against white backed planthopper (WBPH, <i>... 展开 Studies were carried out in Bhubaneswar, Orissa, India, during summer 2002-03 and kharif 2003 to assess the effect of rice cultivars and plant nutrients on the efficacy of an insecticide against white backed planthopper (WBPH, <i>S. furcifera</i>). There were 16 treatments involving 2 rice cultivars (susceptible 'Jaya' and moderately resistant 'Surendra'), 4 nutrient levels (60:30:30 and 120:60:60 kg NPK/ha with and without ZnSO₄ at 25 kg/ha) and insecticide triazophos with untreated control. The insecticide was applied thrice at 30, 45 and 60 days after transplanting. The foliar application of triazophos was more effective in moderately resistant cultivar 'Surendra' than susceptible 'Jaya' in suppressing the hopper population during both summer and <i>kharif</i> seasons. The hopper population increased significantly with the increase in the application of NPK doses and decreased markedly with basal supplementation of ZnSO₄ to the NPK nutrients compared to the application of the corresponding NPK fertilizers alone in both the test cultivars. The effectiveness of the insecticide was pronounced at 60:30:30 kg NPK/ha with ZnSO₄ during summer in minimizing the hopper population (5.35/hill) to the lowest level. 收起