Testing for non-target effects of some fungicides and insecticideson western flower thrips and their predator Amblyseius swirskiiunder plastic tunnel conditions
Abstract: The compatibility of four pesticides (Chlorantraniliprole, Pymetrozine, Trifloxystrobinand Myclobutanil) used with the predatory mite, Amblyseius swirskii (Acari: Phytoseiidae), tocontrol western flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae), wasinvestigated on peppers in plastic tunnels. One preventative release of predatory mites, at the rateof 50 adults per m2, was made from the stock culture when the peppers started to flower. Thewestern flower thrips populations were sampled on a weekly basis and the tested pesticides weresprayed when needed. Our results indicated that applying the tested pesticides had no effect onthe ability of the predator to reduce the thrips population. The thrips populations in the nopredatortreatment continued to expand throughout the experiment, while those in the predatorrelease treatment declined. We concluded that A. swirskii can be used in conjunction with thetested pesticides in pepper greenhouses without causing any obvious detrimental effects to thispredator or reducing the effectiveness of the biological control.