PROBLEM TO BE SOLVED: To provide a DNA encoding a neoxantin-cleaving enzyme used to enhance a stress tolerance of a plant, a method for enhancing the stress tolerance of a plant by transferring the DNA into the plant, a transgenic plant into which a neoxantin-cleaving enzyme gene was transferred, a DNA molecule to be used to reduce the stress tolerance of a plant, a method for reducing the stress tolerance of a plant by transferring the DNA, and a transgenic plant into which the DNA was transferred. SOLUTION: A transgenic plant was prepared into which a sense or antisense neoxantin-cleaving enzyme gene was transferred. A transgenic plant into which the sense gene was transferred had a significantly enhanced stress tolerance while a transgenic plant into which an antisense gene was transferred had significantly reduced one.
