MANAGEMENT OF WESTERN FLOWER THRIPS, FRANKLINJELLA OCCIDENTALS (PERGANDE) (THYSANOPTERA: THRIPTDAE) ON STRAWBERRIES

摘要

Pesticides are required to maintain effective resistance management strategies for control of western flower thrips, Frankliniella occidentalis (Pergande) on strawberries. Novel chemicals that may be suitable for F. occidentalis control in strawberries include acetamiprid, chlorfenapyr and thiamethoxam. New chemicals are required to augment the only chemical currently registered, spinosad. Rates trialled in the field included 0.5 and 1.0 g ai L~(-1) acetamiprid, 0.025 and 0.05 g ai L~(-1) chlorfenapyr, 0.3 and 0.6 g ai L~(-1) thiamethoxam and 0.01 g ai L~(-1) spinosad and were loosely based on the LC99.99 level response of an insecticide susceptible laboratory reference strain. Insecticides were applied every three days giving a total of three successive applications as per the three spray strategy. Insecticides were applied with a Stihl~c backpack mist blower, producing a total spray volume of 800 L ha~(-1.0 Only acetamiprid (1.0 g ai L~(-1)) adequately controlled both adult and larval F. occidentalis. Application of spinosad at the lower than registered rate of 0.1 g ai L~(-1) controlled F. occidentalis larvae and may have a role in integrated pest management strategies that include inundative release of predatory mites.