POSTEMBRYONIC GROWTH AND DEVELOPMENT OF F1 AND F2 TOBACCO BUDWORMS (LEPIDOPTERA: NOCTUIDAE) FROM PARTIALLY STERILE MALES

Abstract

AbstractTobacco budworms, Heliothis virescens (F.), with inherited sterility caused by irradiation of the male parent were smaller than progeny from normal parents and developed more slowly throughout the larval and pupal periods. In the second generation the population segregated into two groups, those with normal and those with delayed development. Also, when the P1 male received 15.0 krad, 8% of the F1 larvae had more than the normal five instars. Moreover, when those F1 progeny that had only five larval instars were outcrossed to normal moths, this tendency for supernumerary molts increased nearly 3-fold. The slower development of progeny of treated moths would have to be considered in field tests made to evaluate the effect of inherited sterility on the tobacco budworm. However, with continuous release of irradiated males, the delayed development or smaller size of the progeny should not lessen the possibility that this method could successfully suppress field populations.