INFLUENCE OF GENETIC CHANGES AND OTHER VARIABLES ON THE ENCAPSULATION OF PARASITES BY HYPHANTRIA CUNEA

Abstract

AbstractThe percentage encapsulation of its common insect parasites by Hyphantria cunea Drury was measured in natural populations in New Brunswick and Nova Scotia over a period of 17 years, and the variables affecting encapsulation were studied in laboratory experiments. Percentage encapsulation varied with the species, stage, and activity of the parasite, and the stage and genetic strain of the host. Differences in encapsulation from area to area and particularly from year to year were closely related to short-term changes in the genetic constitution of the host population resulting from natural selection pressures. The application of these results to biological control and to population modeling is discussed briefly.