EFFET DU STRESS SALIN SUR LA VARIATION D’ISOENZYMES D'ESTERASES DE DEUX GENOTYPES CONTRASTES DE MEDICAGO

Abstract

The activity of the esterases wich is related to the physiological and metabolic stage of the plant cell, can be affected by the environmental factors such as the salt stress. Our study was carried on the native electrophoresis of the esterases isoenzymes, on two ecotypes from two different species of Medicago, the tolerant from M. truncatula Gaertn and the sensitive one from M. polymorpha L. The study of the synthesis of esterases isozymes during germination of seeds under different salt concentration of salinity 0, 68, 102 and 137 mM, showed a specific quantitative and qualitative variations of isoenymes synthesis, between the two contrasting. This biochemical polymorphism of esterases isoenzymes, can be explained by the genetic polymorphism of genes involved in salt stress tolerance in Medicago.