R. K. KALYAN , O. P. AMETA , G. S. AMETA , B. S. RANA AND H. K. JAIN

Field experiments were conducted at the Agricultural Research Station-Banswara (Rajasthan) during kharif 2012 and 2013 to work out the losses in soybean caused by insect pests. The soybean variety JS-335 was sown in 26 plots of 3 × 4 m, having 6 rows. One set of plots was kept protected from insect infestation by regular application of recommended insecticides (protected) and the other set was exposed to natural infestation (unprotected). Infestation by insect pests in soybean significantly affect the plant height causing 8.58 and 11.68 per cent loss, 12.23 and 24.31 per cent loss to number of pods/ plant, 11.06 and 14.86 per cent reduction in seeds/pod, 7.28 and 8.00 per cent loss in weight of 100 seeds, during 2012 and 2013, respectively. The mean yield data recorded from protected and unprotected plots of soybean indicated that insect pests caused 23.79 and 37.16 per cent loss in seed yield, equivalent to a loss of 5.65 and 9.71 q/ha during 2012 and 2013, respectively.