Flower visitation and oviposition behavior of Frankliniella occidentalis (Tysan., Thripidae) on cucumber plants

Abstract

Oviposition behaviour of western flower thrips, Frankliniella occidentalis(Pergande) on greenhouse cucumber, Cucumis satifus(L.) was investigated. Most eggs were laid in the leaves, along veins and under leaf hairs, with only a few on plant stems and flowers. Oviposition rate was higher during the day than during the night. During the day, more adult thrips were found in the flowers than during the night. The number of adult thrips per flower increased rapidly after sunrise with the highest densities occurring around noon and thereafter the number of thrips in flowers decreased during the afternoon. No differences were found in the number of larvae (first and second instars) in flowers during the same period. The number of adult thrips on male and female cucumber flowers was not different, indicating that pollen is not the only attraction in flowers for thrips.