Pectinophora Gossypiella (Lepidoptera: Gelechiidae) and Heliothis Virescens (Lepidoptera: Noctuidae): Moth Emergence from Hot and Cold Temperature Treated Larvae and Pupae

We conducted studies to determine the effects on adult emergence following hot and cold temperature exposures of larvae and pupae of pink bollworm, Pectinophora gossypiella (Saunders) (PBW) and tobacco budworm, Heliothis virescens (F.) (TBW). PBW moth emergence was not affected by exposure of larvae or pupae to temperatures as high as 46oC for 4 h. TBW moth emergence was reduced following exposure of larvae or pupae to 44oC for 4 h. TBW pupae were more tolerant than PBW pupae to cold temperatures as low as 2oC for 120 h. These results suggest high temperature tolerance for PBW compared with TBW and may partially explain the higher numbers of pheromone-baited trap catches of PBW from 1981 to 1988 and its long term economic pest status of cotton in Imperial Valley, California. TBW larvae and pupae were more susceptible to high temperature but more tolerant to colder temperatures.