Sex pheromones and reproductive behavior of Spodoptera litura (Fabricius) moths reared from larvae treated with four insecticides

When Spodoptera litura (Fabricius) larvae were treated with the insecticides deltamethrin, endosulfan, malathion, and carbaryl at dosages causing 30% mortality (LD30), female moths reared from survivors showed similar patterns in the frequency of calling behavior. However, females reared from larvae dosed with deltamethrin had significantly higher titers of sex pheromone than those treated with endosulfan, malathion, or carbaryl, or control individuals. The ratio of the sex pheromone blend, Z9,E12-14:OAc to Z9, E11-14:OAc in females from the deltamethrin treatment group differed significantly from that of female moths in other treatments. In a wind-tunnel bioassay, males reared from larvae treated with deltamethrin, malathion, or carbaryl were less likely to display behaviors resulting in the location of a sex pheromone source than males reared from larvae treated with endosulfan or a solvent control ( acetone). Mating success was significantly decreased in pairs containing either males or females reared from larvae that survived treatment with deltamethrin.