Screening of lentil germplasm and evaluation of insecticides against aphis craccivora (Koch)

A field experiment was conducted in Rabi on lentil (var. NDL-1) during 2014–15 to screen germplasm and evaluation of insecticides. The results revealed that the minimum (mean) aphid population of 2.7 aphid/plant on genotype IPL-316 and maximum (mean) population 13.5 aphid/plant on genotype KLB-09-02 at 50% flowering stage were recorded. Based on overall mean out of 50 germplasm screened against aphid 16 germplasm were graded as resistant and 34 moderately resistant. Imidacloprid 17.8 EC + Dhanubit (0.004%+0.1%) was found most effective; however, it was at par with Imidacloprid 17.8 EC 0.004% alone. As regards cost benefit ratio application of Imidacloprid 17.8EC 0.004% was found most economic with cost benefit of 1: 22.08.

Aphis Craccivora, lentil aphid is the most serious pest feeding on young lentil plants caused reduction in the growth rate and efficiency of production of new tissues at average plant infection level of about 17.5 per cent (Tahhan and Hariri, 1982). Black aphid damage by sucking sap from tender leaves and shoots which retard the plant growth, reduces production and severe attack results in stunted growth or mortality of the plants. Other symptoms include smaller number of deformed and stunted pods. During spring and severe cold, the black aphid prefers tender leaves and cluster in great numbers around the soft succulent stems and terminal buds. During hotter and drier weather of summers, aphids are likely to be scattered and many were found on the underside of the leaves. The lentil aphid occurs regularly and causes considerable damage to the crop and plays an important role in reducing the yield.