Study effect of some insecticides on Thrips tabaci Lindeman (Thys. Thripidae) in West Azarbaijan.Thrips tabaci Lindeman is key pest of onion in different regions of Iran and there are several sprays to control of this pest. For this reason, the replacement of low-risk and high quality insecticides is necessary for controlling this pest. In this research, the efficacy of dichlorvos, deltamethrin, chlorpyrifos, imidacloprid, ethion, abamectin and control against Thrips tabaci in a field in the city of Miandoab, West Azarbayjan of Iran in 2016 was investigated. Experiment was conducted in a completely randomized design with 6 treatments and 3 replications. Thrips density was recorded on 10 plants per block, one day before and 24 hours, 3, 7, 10 and 15 days after spraying. The efficiency of treatments was calculated by Henderson-Tilton method. After analysis of variance, the average grouping was done by Tukey test. The results showed that the mortality rate, 15 days after spraying in chlorpyrifos + abamectin, imidacloprid + ethion and dichlorvos, deltamethrin and chlorpyrifos were 100, 97.2 ± 4.3, 10.71, 86.4 ± 48.4 ± 3.48, and 12.99 ± 0.72 percent respectively. The percentage of mortality of chlorpyrifos combination with abamectin and imidacloprid + ethion was significantly different with other studied insecticides. Chlorpyrifos showed a better effect on the destruction of these pests over time. According to the results of the present study, the combination of abamectin with chlorpyrifos and imidacloprid with ethion because of the highest percentage of mortality can be recommended for effective control of this pest.
Keywords: chemical control, abamectin, chlorpyrifos, ethion, imidacloprid