SUSCEPTIBILITY OF PINK-BOLLWORM (LEPIDOPTERA, GELECHIIDAE) SOIL ASSOCIATED STAGES TO THE ENTOMOPATHOGENIC NEMATODE STEINERNEMA-CARPOCAPSAE (RHABDITIDA, STEINERNEMATIDAE)

Soil associated stages, pupae, and last-instar larvae of the pink boll worm, Pectinophora gossypiella (Saunders) (PBW), were evaluated for su sceptibility to the entomopathogenic nematode, Steinernema carpocapsae (Weiser) (Mexican strain, Kapow selection). Mean mortality responses of PBW larvae entering the soil naturally compared to larvae buried ar tificially (2.5 cm deep) are 99.5 and 73.4%, respectively, at 15 infec tive juveniles/larva. The time required for nematode infection of larv ae (38.0/cm2 soil surface) was 24 h or less. Larval mortality was sign ificantly reduced at 15.6-degrees-C compared with 21.1, 26.7, and 32.2 -degrees-C. Live nematodes were found in PBW larvae at all temperature s tested except 32.2-degrees-C. Reproduction of juveniles was evident 3 days after exposure at 26.7-degrees-C. At 26.7-degrees-C, mortality of nondiapause larvae was not significantly different than diapause la rvae. Pupae were not susceptible unless injured. Entomopathogenic nema todes have potential as a biological control agent for PBW when larvae enter the soil.