TEMPERATURE EFFECTS ON INFECTION AND MORTALITY OF PECTINOPHORA-GOSSYPIELLA (LEPIDOPTERA, GELECHIIDAE) LARVAE BY 2 ENTOMOPATHOGENIC NEMATODESPECIES

Steinernema riobravis Cabanillas, Poinar & Raulston infected pink boll worm, Pectinophora gossypiella (Saunders), larvae over a temperature r ange of 15.6-38.0 degrees C. At temperatures >21.0 degrees C, mortalit y occurred in 24-72 h, but substantial mortality at 15.6 degrees C did not occur until 2-6 d later. In some cases, temperatures of 35.6 and 38.0 degrees C pink bollworm larval mortality by S. riobravis and S. c arpocapsae (Weiser) was lower than temperatures ranging from 21.0 to 3 2.2 degrees C. The adverse effects on efficacy were greater for S. car pocapsae than for S. riobravis. Temperatures of 32.2 degrees C and hig her and exposure for 48 h or more often resulted in decreased numbers of nematode killed larvae with living nematodes and increased numbers of dead larvae with dead or no nematodes.