IPM strategies for western flower thrips, Frankliniella occidentalis, on greenhouse grown chrysanthemums

Western flower thrips, Frankliniella occidentalis, is a major pest of greenhouse ornamental plant production. This thrips species has developed resistance to most classes of insecticides making management difficult. The objective of this study was to develop components of an integrated pest management program for thrips which will aid in overall greenhouse management programs.; Neoseiulus cucumeris and Orius insidiosus were evaluated individually and in combination against F. occidentalis . The combination treatment resulted in significantly lower thrips population than did the control in all of the trials. The combination treatment was not significantly different from the N. cucumeris only treatments. Additional experiments showed O. insidiosus established and distributed evenly, while N. cucumeris only established in one of three trials.; Media drenches with biological agents, insect growth regulators, and contact insecticides were evaluated for reduction of adult F. occidentalis emergence. Diflubenzuron, pyriproxyfen, methiocarb, chlorpyrifos and Metarhizium anisopliae resulted in the greatest reduction of thrips emergence.; A series of experiments were conducted evaluating the combination of control techniques. Fenoxycarb medium drenches and O. insidious releases were evaluated when used in combination to manage F. occidentalis . Under both high and low populations thrips control was not achieved. In two trials, conflicting results were obtained when evaluating Orius establishment when Orius were exposed to applications of the insecticide spinosad. There was no benefit to combining insect attractants with Beauveria bassiana to increase efficacy in controlling F. occidentalis.; The compatibility of insecticides was evaluated against natural enemies. Orius insidiosus, Phytoseiulus persimilis, Encarsia formosa, Aphidius colemani , and Ipheseius degenerans when exposed to Beauveria bassiana were highly susceptible to infection under laboratory conditions while lower infection rates were observed in greenhouse trials. Water and soap resulted in significantly lower Ipheseius degenerans mortalities than neem oil and azadirachtin. Ipheseius degenerans was least susceptible to Metarhizium followed by Verticillium and Beauveria. These data indicate with proper timing applications of mycoinsecticides, azadirachtin, neem oil, and soap can be used together with selective natural enemies.