Reproductive performance and longevity of female European corn borer, Ostrinia nubilalis: effects of multiple mating, delay in mating, and adult feeding

In a recent study on the pheromone-mating disruption of the European corn b orer, Ostrinia nubilalis (Lepidoptera: Crambidae), we recorded a significan t reduction in mating frequency, as well as a marked delay in mating in fer al females captured in disruptant-treated fields. In order to be able to ac curately interpret the results in terms of effective population control, th e current study was undertaken on the effects of multiple matings and a del ay in mating on reproductive performance. Female O. nubilalis that mated at least twice had significantly higher fecundity and fertility, compared wit h once-mated females. In addition, multiple-mated females deposited a signi ficantly larger portion of their egg complement, relative to single-mated o r unmated females. Females that experienced a 3-day delay in mating showed a significant reduction in fecundity compared with females that mated soon after emergence. A 1-week delay in mating resulted in a further reduction i n fecundity and a near zero fertility. The effect of sugar feeding on repro duction was not significant. In general, unmated females lived longer than mated females, and sugar-fed mated females had a higher longevity than wate r-fed mated females. (C) 1999 Elsevier Science Ltd. All rights reserved.