INUNDATIVE RELEASE OF TRICHOGRAMMA BRASSICAE BEZDENKO (HYMENOPTERA: TRICHOGRAMMATIDAE) FOR CONTROL OF EUROPEAN CORN BORER IN SWEET CORN

Abstract

AbstractInundative release of Trichogramma brassicae Bezdenko for control of European corn borer was tested in experimental plots in 1991 and 1992 in southern Alberta, Canada, to determine its effectiveness as a potential method of control in sweet corn. The tests were conducted in 1-ha plots, in three different fields of irrigated sweet corn each year, at a release level of about 196 000 wasps per ha. The reduction in European corn borer damage in the release plots ranged from 85 to 87% in 1991 and from 45 to 95% in 1992. The reduction in damage was not significantly different in fields with 25 and 49 release points. General area degree-day accumulation for postdiapause development was not adequate to determine the timing of release for individual fields because European corn borer phenology varied among fields. Total moth catch in pheromone traps, however, was directly related to the number of plants damaged by European corn borer, and releases near the time of peak trap catch produced the greatest reduction in damage.