EFFECT OF Verticillium lecanii ON THE TWO COTTON BOLLWORMS, Earias insulana BOISD. AND Pectinophora gossypiella (SAUND.) (LEPIDOPTERA)

Document Type : Original Article

Authors

Plant Protection Research Inst., Agric. Res. Center, Dokki, Giza, Egypt

Abstract

Laboratory bioassays of the fungus, Verticillum lecanii against different stages of the two cotton bollworms, Earias insulana Boisd. and Pectinophora gossypiella (Saund.) under different concentrations of fungus were studied. The fungus proved virulent efficacy against eggs and larvae of both pests treated eggs of both insect pests caused a reduction rate in the hatchability whereas eggs hatchability was reduced for both insect pests. It was evident that eggs and larvae of both insects were susceptible to fungal infection and most of hatched larvae from treated eggs failed to develop to adults and dead in both E. insulana and P. gossypiella. LC50 values against        E. insulana eggs and larvae were  1.1X107 spores/ml and 1.8X107 spores/ml, respectively; whereas  LC50 values against P. gossypiella eggs and larvae were  1X107 spores/ml and 1.5X107 spores/ml, respectively. Data clarified that P. gossypiella was more susceptible to the fungal than E. insulana through all the tested stages.