The effect of immigration on genetic control : A laboratory study with wild and compound chromosome stocks of Drosophila melanogaster.

Immigration by wild type flies into an established compound chromosome control zone was studied in the laboratory using discrete generation population cages. Immigration rates of less than 10 % per generation by virgin migrants were unlikely to disrupt the zone. However, the zone could be disrupted by immigration rates of 0.5 % if the migrants had mated. The curvilinear relationship between the number of generations to fixation of the migrant genotype and the immigration rate suggested a possible equilibrium between immigration rate and the maintenance of a control zone. -The importance of the results to the strategy of a particular control program is emphasized, as is the need for an integrated multi-disciplinary approach to insect pest management.