MATING FREQUENCY OF THE FEMALE EUROPEAN CORN BORER, OSTRINIA NUBILALIS (LEPIDOPTERA: PYRALIDAE), IN SOUTHWESTERN ONTARIO

Abstract

AbstractEuropean corn borer moths were caught in an ultraviolet light trap from early June to late October at Harrow, Ont. Two conspicuous peaks of light trap catches occurred each year, corresponding to two generations, but a third generation was deduced from three peaks of occurrence of virgin females. The number of moths which could be caught with nets in the day time correlated with the light trap catch of the previous night (r = 0.7). Most of the moths caught in the light trap or in nets were females but males predominated in the early June, September, and October catches. The shortage of males in the second generation was shown to influence the proportion of females mating, but not the number of spermatophores per female. Most females mated once and the number of matings per female did not differ enough between years to account for differences in adult populations.