A method of finding a compound which increases the tolerance to abiotic stress factors in plants, where the increase in the transcription or expression of individual plant-endogenous genes is regarded as proof for the induction. Independent claims are: (1) a method of increasing the yield in crops of useful plants comprises treating the useful plants by seed dressing, by foliar sprays or by soil application, with the compound which increases the tolerance to abiotic stress factors in plants or compounds which are already known as safeners in crop protection； (2) a method of extending the vegetation period in crops of useful plants, which comprises treating the useful plants by seed dressing, by foliar sprays or by soil application, with the compound which increases the tolerance to abiotic stress factors in plants or compounds which are already known as safeners in crop protection； (3) a method of making possible an earlier sowing date in crops of useful plants, which comprises treating the useful plants by seed dressing, by foliar sprays or by soil application, with the compound which increases the tolerance to abiotic stress factors in plants or compounds which are already known as safeners in crop protection； and (4) a method of increasing the quality in crops of useful plants, which comprises treating the useful plants by seed dressing, by foliar sprays or by soil application, with the compound which increases the tolerance to abiotic stress factors in plants or compounds which are already known as safeners in crop protection. ACTIVITY : Plant Protectant. MECHANISM OF ACTION : None given.
