Voltinism and the induction of aestival diapause in the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

Overwintering populations of Colorado potato beetle in upstate New York and on Long Island are composed of adults from both the 1st and 2nd summer generations. The critical photoperiod for aestival diapause induction is longer, and the induction of diapause by low temperature is greater, in the population from the cooler, inland locality (upstate New York) than in the population from the warm coastal area. Under the long days of early summer, temperature appears to influence aestival diapause induction and voltinism at both localities. A large proportion of 1st-generation adults enters diapause either without ovipositing or after ovipositing for a brief period. -from Authors