Benzoxazoles, benzothiazoles and benzimidazoles having substituents on the azole and benzene nuclei were synthesized evaluated for antifungal, insecticidal and herbicidal activities. It was found that benzimidazoles tended to exhibit antifungal activity while benzothiazoles tended to show herbicidal activity. Chloro, trifluoromethyl, methoxy and ethoxy groups at the 5 position were potent substituents, and the 2-pyridyl group at the 2 position is a common structural unit. Among several active derivatives, 7-chloro-2-(2-pyridyl) benzimidazole and 2-(2-pyridyl)-5-trifluoromethylbenzothiazole exhibited significant activity against Panonycus citri.