Attraction of pest thrips (Thysanoptera: Thripidae) infesting French beans to coloured sticky traps with Lurem-TR and its utility for monitoring thrips populations

In the present study, experiments were carried out in French bean fields over two planting periods to evaluate the potential use of sticky traps for monitoring the populations of pest thrips. To this end, blue, yellow and clear sticky traps (with and without a thrips lure, i.e. Lurem-TR) were tested. Field observations on thrips catches were made at weekly intervals from the sticky traps, and absolute estimates of thrips populations and their natural enemies were made by destructive (picking leaves and flowers) and non-destructive sampling (plant tapping) of plants until crop senescence during the two planting periods. Blue traps caught two and three times more thrips compared with yellow traps over the first and second planting periods, respectively. Blue traps were more attractive to Megalurothrips sjostedti (Trybom), Frankliniella schultzei (Trybom) and Frankliniella occidentalis (Pergande), while yellow traps were only attractive to Hydatothrips adolfifriderici (Karny) and the natural enemies of thrips. The addition of Lurem-TR to the sticky traps significantly increased the capture of all thrips species, but not their natural enemies. The estimates of thrips populations from blue sticky traps with Lurem-TR were found to be highly correlated (r= 0.95; P< 0.001) with the absolute estimates of thrips using the destructive sampling method. The results demonstrate that blue sticky traps and Lurem-TR can be an efficient tool for the monitoring of thrips populations on French beans with least influence on their natural enemies. © ICIPE 2014.