Lethal and Sublethal Effects of Some Chemical and Biological Insecticides on Tuta absoluta (Lepidoptera: Gelechiidae) Eggs and Neonates.

Abstract

Tuta absoluta (Meyrick) is one of the serious pests of tomatoes. This study was conducted to evaluate the effects of some chemical and biological insecticides on T. absoluta. The insecticides tested were diazinon, dichlorvos, chlorantraniliprole, deltamethrin, acetamiprid, imidacloprid, spinosad, abamectin, indoxacarb, Bacillus thuringiensis Berliner, Beauveria bassiana (Balsamo) Vuillemin, and Metarhizium anisopliae (Metschnikoff) Sorokin. Sublethal effects for the most effective insecticides tested, namely, abamectin, spinosad, chlorantraniliprole, and indoxacarb were assessed, and life table parameters were calculated. Chlorantraniliprole had the highest lethal effect on T. absoluta followed by spinosad, abamectin, and indoxacarb. On the other hand, imidacloprid was not considerably effective on T. absoluta eggs. Metarhizium anisopliae was 11 and 518 times more effective on the eggs and newly hatched larvae than B. bassiana and B. thuringiensis, respectively. Chlorantraniliprole, spinosad, abamectin, and indoxacarb affected life table parameters of T. absoluta significantly (α = 0.05). Spinosad had the highest sublethal effect on T. absoluta followed by abamectin, chlorantraniliprole, and indoxacarb. The results revealed that chlorantraniliprole, spinosad, abamectin, and indoxacarb had considerable lethal and sublethal effects on T. absoluta, and if they perform similarly in commercial greenhouses and fields, they would be suitable candidates to be considered in IPM programs for this pest.