Air Permeation with Gossyplure: Feasibility Studies on Chemical Confusion for Control of the Pink Bollworm123

Abstract

In laboratory experiments, adult Pectinophora gossypiella (Saunders) mated as frequently in gossyplure permeated atmospheres as in untreated atmospheres. Male moths with antennae ablated at the basal segment did not mate. Males with 2–5 antennal segments remaining and females with antennae ablated at the basal segment were able to mate but did so less frequently than unaltered moths. Males with only antennal tips removed mated as frequently as untreated males. We concluded that males require olfactory stimulation to mate and that close range chemical communication takes place even in an atmosphere permeated with gossyplure. Moths from preadapted pupae mated as frequently in continuous total darkness as did those held in continuous light, suggesting that visual cues are not essential for mating in this species. Flight activities recorded from field experiments and laboratory observations indicate that male moths fly at random in untreated and pheromone permeated atmospheres. This behavior presumably functions to bring males within some critical distance of calling females where pheromone diffusion gradients provide short range orientational cues. We estimate a large number of random male-female encounters that could result in many matings in normal postdiapause field populations of the pink bollworm. Male random movement may be an effective mate acquisition strategy within a host patch and this behavior may thwart attempts to control the pink bollworm by chemical confusion with gossyplure in fields previously planted to cotton.