Flower visitation and oviposition behaviour of Frankliniella occidentalis (Thysan., Thripidae) on cucumber plants

Oviposition behaviour of western flower thrips, Frankliniella occidentalis (Pergande) on greenhouse cucumber, Cucumis satifus (L.) was investigated. M ost eggs were laid in the leaves, along veins and under leaf hairs, with on ly 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 i ncreased rapidly after sunrise with the highest densities occurring around noon and thereafter the number of thrips in flowers decreased during the af ternoon. No differences were found in the number of larvae (first and secon d 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 Bowers for thrips.