EFFICACY OF DIFFERENT INSECTICIDAL TREATMENT SCHEDULES AGAINST MANGO LEAF GALL MIDGE Procontarinia matteiana, (KIEFFER & CECCONI)

India is the largest producer of mango in the world but in terms of productivity, it is the lowest among the top five countries. One of the major problems facing the mango industry is pest complexes that damage fruits, flowers, stems, and leaves. Mango is attacked by more than 400 pests in the world. Mango leaves are attacked by many species of Cecidomyiidae especially of the genera Procontarinia. The most common and widespread species is Procontarinia matteiana (Kieffer & Cecconi), a well-known pest of mango in Asia and Africa. The adult midge is a minute fly and dies within 24 hours of emergence after copulation and oviposition. On hatching maggots bore inside the leaf tissues, and feed within, resulting in the formation of small wart-like galls on leaves. Heavily galled leaves curled up and drop prematurely. As a result, it hampers the photo-synthetic efficiency and upset normal physiological activity of the tree resulting in reduced yields of mango fruits. Therefore a study was conducted at a private orchard in Chhotajagulia, North 24 Parganas, West Bengal, India on selected uniform plants (cv. Himsagar) to evaluate the bioefficacy of new insecticides mixtures along with conventional insecticides against mango leaf gall midge in two consecutive seasons (2017-18). The experiment was laid in a randomized block design with three replications of each treatment and an untreated check of water spray. The experiment comprised of eight treatments including the control. Five hundred leaves were randomly selected from a branch to observe and calculate the percentage of newly formed as well as mature galls on fresh leaves. The damage was assessed at weekly interval by counting total leaves versus the infested one. From the study it is revealed that the combination of beta-cyfluthrin 9% +imidacloprid 21% 300 OD@ 75 g a.i/ha was most effective to reduce leaf gall infestation followed by thiamethoxam 12.6% + lambda cyhalothrin 9.5% 247 ZC @ 22 g a.i/ha.