INSECTICIDAL ACTIVITIES OF THYMOL ON EGG PRODUCTION AND DEVELOPMENT IN THE DIAMONDBACK MOTH, PLUTELLA XYLOSTELLA (LEPIDOPTERA).

Abstract

The insecticidal activity of thymol was evaluated in the laboratory against third instar Plutella xylostella by topical application. Our previous results described mortality in P. xylostella by thymol and the present study continues investigation for its possible efficacy on egg production and development in surviving treated P. xylostella. Our results showed that thymol at a sublethal dose (0.43 µg/larvae, LD₃₀) caused pupation inhibition, adult-emergence inhibition and abnormal adults at rates of 30, 33.33 and 23.33%, respectively. Moreover, the number of eggs was also reduced by 54.33%. These results showed that thymol was active against P. xylostella larvae and can effectively control this pest.