DERIVATIVES OF ACETIC ACID FOR INCREASING ABIOTIC STRESS TOLERANCE OF CULTIVATED PLANTS

The present invention relates to the use of the compounds of the following general formula (I) and their agriculturally acceptable salts, wherein R is a phenyl group or a five- or six-membered unsaturated heterocyclic ring containing nitrogen as heteroatom; R is a hydrogen atom or a lower alkyl group; X is an amino group optionally substituted with one or two lower alkyl groups; or a halogen atom, preferably chlorine or bromine; Y is a hydroxyl group, a lower alkoxy group, an amino group optionally substituted with a five- or six-membered saturated heterocyclic ring containing two identical or different heteroatoms selected from nitrogen and oxygen atoms or with a lower carboxyalkyl group, or an amino group the substituents of which are replacing both of its hydrogen atoms and are forming with the enclosed nitrogen atom a five- or six-membered heterocyclic group containing two nitrogen atoms, where the other nitrogen atom is optionally substituted by a lower alkyl group; as well as to the use of compositions containing these compounds or their agriculturally acceptable salts and methods for increasing abiotic stress tolerance of cultivated plants, inhibiting the senescence of seeds and enhancing their vigour under stress conditions. The invention also relates to a narrower group of the compounds of the above general formula which are new; in these compounds the meaning of the substituents are as defined above with the proviso that if R is a hydrogen atom or a lower alkyl group, X is a halogen atom and Y is a lower alkoxyl group, then R can only be a five- or six-membered unsaturated heterocyclic ring containing nitrogen as a heteroatom. L'invention concerne l'utilisation de composés représentés par la formule générale (I) ainsi que leurs sels acceptables sur le plan agricole. Dans cette formule, R représente un groupe phényle ou un anneau hétérocyclique non saturé à cinq ou six chaînons contenant un hétéro-atome de nitrogène, R représente un atome d'hydrogène ou un groupe alkyle inférieur, X représente un groupe aminé éventuellement substitué avec un ou deux groupes alkyle inférieurs, ou un atome d'halogène, de préférence de chlore ou de brome, Y représente un groupe hydroxyle, un groupe alcoxy inférieur, un groupe aminé éventuellement substitué avec un anneau hétérocyclique saturé à cinq ou six chaînons contenant deux hétéro-atomes identiques ou différents choisis dans le groupe comprenant des atomes de nitrogène et d'oxygène, ou avec un groupe carboxyalk