The Mode of Overwintering of Trichogramma nubilale Ertle and Davis

Laboratory experiments were conducted using a variety of photoperiod and temperature conditions to determine the mode of overwintering exhibited by Trichogramma nubilale Ertle and Davis. The results of these tests show that T. nubilale probably overwinters by hibernation in host eggs. In addition, it was determined that overwintering success is optimal for those parasites which developed to the pupal stage In eggs of the European corn borer, Ostrinia nubilalis (Hubner).