Bio-efficacy of diffrent insecticides against Lucerne aphid

Investigations on bioefficacy of different insecticides against lucerne aphid were carried out under field condition during 2018-19 at Instructional Farm, Junagadh Agricultural University, Junagadh. Based on the spray of insecticides aphid can be effectively managed by acetamiprid 20 SP @ 0.008 percent followed by thiamethoxam 25 WG @ 0.01 percent and imidacloprid 17.8 SL @ 0.005 percent. While carbosulfan 25 EC @ 0.01 percent found least effective in controlling lucerne aphid. The highest yield of lucerne 37.20 q /ha was obtained from the treatment of acetamiprid 20 SP @ 0.008 percent followed by thiamethoxam 25 WG @ 0.01 percent (36 q /ha). While the lowest yield of lucerne was recorded in carbosulfan 25 EC @ 0.01 percent with 26.07 q/ha yield of lucerne. The highest incremental cost benefit ratio (1:56.97) was obtained from the treatment of acetamiprid 20 SP @ 0.008 percent. It was followed by imidacloprid 17.8 @ 0.005 percent (1:49.42), clothianidin 50 WDG @ 0.025 percent (1: 49.29). The other treatments such as carbosulfan 25 EC @ 0.01 percent (1:30.89), triazophos 40 EC @ 0.08 percent (1:28.89) registered low cost benefit ratio.