PROBLEM TO BE SOLVED: To provide a plant activator having low soil pollution and toxicity and excellent in resistance inducing effect and growth promoting effect, and a method for producing the same. SOLUTION: A plant activator containing a fatty acid metabolite obtained by metabolizing a fatty acid having 4 to 30 carbon atoms into a proteobacteria under a dissolved oxygen concentration environment of 0.1 to 8 mg/l, and 4 to 30 carbon atoms. A method for producing a plant activator containing a fatty acid metabolite, which comprises a fatty acid metabolizing step of metabolizing the fatty acid of 1. to a proteobacteria under a dissolved oxygen concentration environment of 0.1 to 8 mg/l. [Selection diagram] None【課題】土壌汚染や毒性が低く、抵抗性誘導効果および成長促進効果に優れた植物賦活剤、およびその製造方法を提供すること目的とする。【解決手段】炭素数４～３０の脂肪酸を０．１～８ｍｇ／ｌの溶存酸素濃度環境下でプロテオバクテリアに代謝させることで得られる脂肪酸代謝物を含む植物賦活剤、および炭素数４～３０の脂肪酸を０．１～８ｍｇ／ｌの溶存酸素濃度環境下でプロテオバクテリアに代謝させる脂肪酸代謝工程を含む、脂肪酸代謝物を含む植物賦活剤の製造方法。【選択図】なし
