Stink bug Agonoscelis spp. (Heteroptera: Pentatomidae) – An emerging threat for seed production in alfalfa crop (Medicago sativa L.) and their successful management

Fodder crops play an important role in sustainable agriculture as they provide feed for animals, which is ultimately converted to human food. Alfalfa is one of the most important fodder crops having high nutritive value for livestock. However, seed production of alfalfa crop is seriously affected by several factors and the highest reduction in seed yield is caused by stink bug infestation. The current study evaluated different insecticides to control stink bugs during 2016–17. The efficacy of ten insecticides, i.e., acephate, dimethoate, malathion, chlorpyriphos, bifenthrin, lambdacyhalothrin, deltamethrin, acetamiprid, imidacloprid and carbosulfan was tested on Agonoscelis spp. (Heteroptera Pentatomidae). The mortality of stink bug was recorded at one, three, five, seven, ten and fifteen days after insecticide application. Similarly, the population of pollinators was recorded before and one, three and five days after the application of insecticides. It was observed that acetamiprid (81.14%) and acephate (80.65%) caused the highest mortality of stink bug and proved most effective. Insecticides application decreased the pollinators’ population one day after spray; however, it was rehabilitated three days after insecticide application. Insecticide application increased seed yield from 28.05 kg/acre (during last four year without chemical control) to 116 kg/acre in 2016–17 (with chemical control). It is concluded that acetamiprid and acephate can be successfully used in integrated management program of increasing alfalfa seed production.