Susceptibility of the European earwig <i>Forficula auricularia</i> to insecticide residues on apple leaves

Abstract

The European earwig (Forficula auricularia) is potentially a predator of a number of insect pests in apple orchards However its effectiveness as a natural enemy in apple orchards may be compromised by insecticide sprays A laboratory bioassay of eight insecticides currently used in Integrated Fruit Production (IFP) apple orchards and one asyet unregistered product was undertaken to determine their effects on earwigs Adult earwigs were placed in ventilated containers where they were exposed to insecticide residues on apple leaves and monitored on four occasions over 10 days Indoxacarb thiacloprid spinosad and diazinon caused the greatest mortality to earwigs while carbaryl appeared to be less harmful Chlorantraniliprole spirotetramat emamectin benzoate and methoxyfenozide caused no increased mortality of earwigs compared with the control Identification and avoidance of harmful insecticides may help to enhance the potential of earwigs as natural enemies in apple orchards