A research on side effects of some pesticides to nesidiocoris tenuis reuter (Hemiptera: Miridae) in field conditions

The side effects of pesticides to the beneficial insects are predominantly determined by laboratory trials as in Nesidiocoris tenuis. However, laboratory and field tests are not always produced parallel results with each other. For this reason, it is important to perform side effects trials under field conditions. In this study, five active ingredients, spinetoram, chlorantraniliprole+abamectin, chlorantraniliprole+thiamethoxam, emamectin benzoate and dimethoate (standard toxic) were tested for contact toxicity to N. tenuis used in protected tomato cultivation. After pesticide applications, predators were counted on days 1, 4, 7, 14, 21 and 28. As a result of contact effects test, spinetoram was classified as harmless or less harmful (N) with 32.27% mean mortality rates. Chlorantraniliprole+ abamectin produced 57.84% mean mortality and classified, moderately harmful (M). Chlorantraniliprole+ thiamethoxam increased its effect dramatically from the seventh day after application and was caused by an average mortality rate of 55.21% from this day. Emamectin benzoate and dimethoate caused the highest mortality with 79.06% and was 97.15% and found to be harmful (T). The residual effects of 3 different pesticides, which are classified as moderately harmful and harmful in contact tests, were examined. No adverse effects were seen in the 14-day residue of chlorantraniliprole+abamectin, while the 7-day residue had 37.50% mortality and both residues were classified as harmless or less harmful (N). The residues of chlorantraniliprole+thiamethoxam in both 7 and 14 days were classified as harmful (T) with a 100% negative effect. In the case of emamectin benzoate, the mortality rate was 31.3% in 7-day residues, whereas it was higher in the 14-day residue with a 75.0% mortality rate and was classified as harmful.