Bioefficacy of plant based insecticides against thrips, Pseudodendrothrips mori (Niwa) and leaf webber, Diaphania pulverulentalis (Hampson) in mulberry ecosystem and their bio safety to natural enemies

Morus spp. is the sole food for mulberry silkworms, Bombyx mori L. However, this crop is infested by two major pests, the leaf webber, Diaphania pulverulentalis (Hampson) and thrips, Pseudodendrothrips mori (Niwa). To address this, two field trials were conducted in two different locations to assess the efficacy of botanicals against thrips and leaf webber in mulberry ecosystem. Results indicated that TNAU Bio 3G extract @ 5% showed the highest per cent population reduction of thrips (56.24 and 47.24 % in first and second trial, respectively) over untreated control after neem oil @ 3% and neem seed kernel extract @ 5% used as standard check, whereas for leaf webber Eupatorium adenophorum extract @ 3 % showed the highest effectiveness with 61.22 and 61.86 % reduction over control in first and second trial, respectively. The different botanicals applied against mulberry thrips and leaf webber were tested for their effect on mortality of silkworm. It was found that when treated leaves were fed one day after treatment highest larval mortality (25.00%) was recorded in Neem oil @ 3% but it was very low in case of TNAU Bio 3G extract @ 5% (4.99%). Larval death steadily decreased in all the treatments except Neem oil @3 %, when fed two days later, whereas, no mortality was noticed in case of TNAU Bio 3G extract @ 5% and E.adenophorum at 2 DAT. To conclude, TNAU Bio 3G extract @ 5% and E. adenophorum extract @ 3% can be recommended for an eco-friendly and sustainable management of thrips and leaf webber in mulberry ecosystem.