Monitoring the seasonal flight activity of Cydia pomonella and Argyrotaenia velutinana (Lepidoptera: Tortricidae) in apple orchards by using pheromone-baited traps

Abstract

Codling moth, Cydia pomonella (L.), and redbanded leafroller, Argyrotaenia velutinana (Walker), are two key tortricid orchard pests in Minnesota. Field trials were conducted during 2001 and 2002 in Minnesota apple orchards to determine seasonal phenology of C. pomonella and A. velutinana and to evaluate two popular trap designs (Pherocon ICP or IC "Wing" trap versus Pherocon VI "delta" trap) for monitoring both species. Trap performance was determined by comparing the number of males captured, date of first moth capture, and the capture of nontarget beneficial insects. For C. pomonella, two distinct flight periods were recorded, suggesting two generations per year in Minnesota. Emergence and flight activity of first generation C. pomonella began at ≈110 degree-days (DD) base 10°F. This corresponded to apple bloom in southern Minnesota. The delta trap captured significantly more C. pomonella males than the wing trap (Pherocon ICP version). For A. velutinana, three flight periods were recorded at all three locations in both years of the study. The first flight began at ≈55 DD base 10°F, around the tight cluster stage of apple in southern Minnesota. Both trap types captured approximately the same numbers of A. velutinana males in both years of this study. For both species, the dates of first moth capture were generally the same for both trap types, indicating that both types of traps are capable of detecting the first flights of C. pomonella and A. velutinana males. In general, the delta trap was less selective than the wing trap (Pherocon 1C), capturing significantly more nontarget beneficial insects, in particular bees.