Mating Ability of Irradiated Male Boll Weevils Treated with Diflubenzuron or Penfluron

Treatment of young males of Anthonomus grandis grandis Boheman with acetone solutions of diflubenzuron (Dimilin®, TH-6040), or penfluron impaired mating ability. Mating success was often reduced by as much as 40–50%. Affected males usually tried to copulate with virgin females but their movements were often poorly coordinated. They sometimes achieved a partial penetration of the aedeagus without transferring sperm. The males were unable to recover from this deficiency. This problem was largely eliminated when the males were allowed to age for at least 3 days before treatment. Diflubenzuron applied as a 0.1 % acetone dip by itself failed to completely suppress the production of progeny by females. However, when combined with 8000 rad of gamma irradiation, progeny suppression was complete.