Evaluation of bio-efficacy of spinetoram 25% WG against cotton thrips Thrips tabaci

Abstract

Thrips Thrips tabaci is one of the important insect pests of cotton crop, causing severe damage in the early stage of the crop and is developed resistance to most of insecticides. In the present study, novel insecticides and formulation was evaluated against T.tabaci. The results indicated that, the significantly lowest thrips population was noticed in the treatment Spinetoram 25% WG @ 45 g a.i./ha (4.53 thrips/leaf) fourteen days after the first spray, which was on par with the treatment Spinetoram 25% WG @ 36 g a.i./ha (4.58 thrips/leaf). Percent reduction over control was significantly highest in the treatment Spinetoram 25% WG @ 45 g a.i./ha with 72.71. Similarly, the lowest thrips populations were recorded in the treatment Spinetoram 25% WG @ 45 g a.i./ha with 0.88 thrips/leaf fourteen days after the second spray. Significant maximum percent reduction over control was exhibited in the treatments with Spinetoram 25% WG @ 45 g a.i./ha with 92.16 percent. The maximum yield was recorded in the treatment of Spinetoram 25% WG @ 45 g a.i./ha (22.50 q/ha), which was on par with the treatment Spinetoram 25% WG @ 36 g a.i./ha (21.75q/ha). The Spinetoram 25% WG did not affect natural enemies in cotton and did not cause phytotoxicity symptoms even when sprayed @ 72 g a.i./ha