Antgonistic and synergistic activities of precocene 2 on the toxicity of permethrin and carbofuran to rice brown planthopper, Nilaparvata lugens (Stal) (Homoptera: Delphacidae)
ABSTRACT: Precocene 2, (2 – 2 – dimethyl, 6, 7 – dimethoxy chromene) an antijuvenile hormone
compound, was tested for its antagonistic and synergistic effects on the toxicity of permethrin and carbofuran to adults of Japanese and Philippine strains of the rice brown planthopper, Nilaparvata lugens (Stal). Precocene 2 synergised permethrin; carbofuran was synergised and antagonised by precocene 2 depending on the mixture ratio of the compounds. The greatest synergistic action was achieved with a 1:10 combination. Possible mechanisms of antagonism and synergism of precocene 2 are discussed.