Chemical control of the European tarnished plant bug, Lygus rugulipennis, on strawberry in the UK

European tarnished plant bug, Lygus rugulipennis, is a serious pest on late season strawberries in the UK. Feeding by the pest on the developing fruits causes severe malformation, and over 50% of fruit may be downgraded as a result of capsid feeding in unsprayed crops. A range of compounds was tested against the pest over two years at East Malling Research. In 2008 experiments were conducted on weed plots with high L. rugulipennis populations, and in 2009 were conducted on an everbearer strawberry planting. The 2008 experiments showed that etoxazole had no effect on L. rugulipennis and that although flonicamid and indoxacarb significantly reduced populations they were not as effective as thiacloprid, either with or without a surfactant, or acetamiprid. In the 2009 experiment on strawberry thiacloprid + surfactant, applied twice, was more effective than this treatment applied once, which in turn was more effective than thiacloprid alone. In both years the most effective treatment was the pyrethroid bifenthrin. There was no suggestion that different developmental stages of the pest were more susceptible to the tested insecticides. Thus there was no evidence to suggest that timing applications against specific life stages would significantly improve pest control.

► Flonicamid and indoxacarb were not as effective as thiacloprid or acetamiprid.
► Two applications of thiacloprid + surfactant were more effective than one.
► All stages of Lygus rugulipennis showed similar responses to pesticides.
► These insecticides do not need to be targeted at specific life stages of the pest.