Susceptibility of eight apple varieties to damage by Forficula auricularia L. (Dermaptera: forficulidae), an effective predator of Eriosoma lanigerum Hausmann (Hemiptera: aphididae)

Overseas Forficula auricularia L. is recorded as a pest of apple. In Australia however it has been shown capable of providing biological control of Eriosoma lanigerum Hausmann in apple orchards. Laboratory, field cage and crop assessments at harvest were used to identify and determine the extent of damage caused by F. auricularia to varieties of apple grown commercially in Australia. In the laboratory, in the absence of alternative food sources, the varieties Golden Delicious and Sundowner were susceptible to F. auricularia damage and most damage occurred on or close to the calyx. No damage was recorded on Granny Smith, Jonathan, Red Delicious, Red Fuji and Smoothe. In field cages Red Delicious and Granny Smith were not damaged, and the variety Jonathan was damaged in December but not in January or February. At harvest, F. auricularia damage was difficult to distinguish from that caused by the Light Brown Apple moth Epiphyas postvittana (Walker). Damage attributed to F. auricularia in Jonathan was 2.48%, Red Delicious 1.77% and Granny Smith 0.39%.