A STRAIN DIFFERENCE AND ABLATION EXPERIMENTS INVOLVING A DISPERSAL PHEROMONE IN THE GERMAN COCKROACH, BLATTELLA GERMANICA (DICTYOPTERA: BLATTELLIDAE)

The results of bioassays involving a dispersal pheromone that is secreted by adult female German cockroaches are described. Males with excised antennae were unable to sense the dispersant. Repellency to males with excised maxillary palps did not differ significantly from that in the controls. Males of an insecticide - resistant field strain responded more strongly to the dispersant than males of a susceptible laboratory strain. Filter papers conditioned by crowded field strain females were more repellent than papers conditioned similarly by laboratory strain females.