Study on the efficacy of Cruiser and Gaucho insecticides as seed treatments of oilseed rape to control flea beetles

Flea beetles (Chrysomelidae: Alticinae) are the pests of vegetative phase of oilseed rape (Brassica napus). Adult flea beetles feed on cotyledons and young leaves of the crop causing damage. In order to investigate the efficacy of Cruiser and Gaucho insecticides as seed treatments to reduce the pest damage, this project was conducted in a randomized complete block design with 5 treatments and 4 replications at Sari during 2009-10 and 2011-12. The treatments were control (untreated seeds), treated seeds with imidacloprid (Gaucho WS70%) 12 g/kg and 14 g/kg, treated seeds with thiamethoxam (Cruiser FS350) 7 ml/kg and 10 ml/kg. The coefficient of infestation (the number of healthy, slightly and seriously damage plants over 1 m2) was determined. The number of flea beetle larvae in the plant tissue, the yield as well as 1000 kernel weight was calculated. The results showed that both Gaucho and Cruiser with the applied doses for seed treatments had good efficacy in control of the flea beetles compare with control. Among those, thiamethoxam (Cruiser FS350) 10 ml/kg and imidacloprid (Gaucho WS70%) 14 g/kg were found to be more beneficial.