The impact of a number of insecticides on Empoasca vitis populationsin north-eastern Italy

Abstract: The green leafhopper Empoasca vitis Goethe (Homoptera: Cicadellidae) is an importantpest of grapes in Europe. Its feeding activity may cause a reduction in photosynthesis, mesophyllconductance and transpiration rate with implication for yields. For these reasons insecticides arewidely used to control this pest with potential effects on beneficial arthropods. Field experimentswere conducted to evaluate the impact of a number of insecticides (chlorpyriphos, flufenoxuron,thiamethoxam, and indoxacarb) on E. vitis populations. Pesticide side-effects on the predatory miteTyphlodromus pyri were assessed. Thiamethoxam was the most effective towards E. vitis. Pestpopulation levels were slightly reduced by chlorpyriphos, suggesting that this strain was resistant toorganophosphates. Indoxacarb and flufenoxuron were associated to intermediate effects. Thepredatory mite populations were affected especially by thiamethoxam.