PROBLEM TO BE SOLVED: To provide a 2-methyl-3-quinoline compound having excellent insecticidal and bactericidal activities or a salt thereof, and an insecticidal bactericide for agricultural and horticultural use containing the same.SOLUTION: The present invention provides a 2-methyl-3-quinoline compound represented by formula (I) or a salt thereof, and an insecticidal bactericide for agricultural and horticultural use containing the same. [X5-X8 independently represent H, a halogen atom or an alkyl group W is an alkyl group or alkynyl group A is an aryl group substituted with a halogen atom and the like].SELECTED DRAWING: NoneCOPYRIGHT: (C)2018,JPO&INPIT【課題】優れた殺虫活性及び優れた殺菌活性を有する2-メチル-3-キノリン化合物又はその塩並びにこれを含有する農園芸用殺虫殺菌剤の提供。【解決手段】式(I)で表される2-メチル-3-キノリン化合物又はその塩並びにこれを含有する農園芸用殺虫殺菌剤。〔X5~X8は各々独立にH、ハロゲン原子又はアルキル基;Wはアルキル基又はアルキニル基;Aはハロゲン原子等で置換されたアリール基〕【選択図】なし