Sublethal effects of selected insecticides on Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)

In this study, sublethal effects of two insecticides, imidacloprid and spinosad, which are used against western flower thrips Frankliniella occidentalis (Pergande) and other pests in greenhouses of Antalya was investigated. Sublethal effects included effect on fecundity (number of larvae per female), duration of development of eggs, larvae and pseudopupae, and total development, longevity and sex ratio. Second star larvae of F. occidentalis were exposed for 24 h to LC30 doses of insecticides on bean leaf discs dipped into insecticide solutions. After exposure surviving larvae were transferred over to clean bean leaf discs and were reared to adulthood. The number of larvae per female was determined from the larvae emerged from the eggs laid into tissue of bean pod pieces by these adults. The length of egg, larval, pseudopupal and total development, longevity and sex ratio was determined over these larvae, and peudupupae and adults emerged from them. Both insecticides, imidacloprid and spinosad significantly reduced the number of larvae per female and lead to signifcantly longer durations of egg, larval, pseudopupal and total development, but shorter longevity. No effects were detected on sex ratio.