EFFET DU STRESS SALIN SUR DEUX PARAMÈTRES HYDRIQUES (TURGESCENCE ET TRANSPIRATION) DE JEUNES PLANTS D’ATRIPLEX HALIMUS ET ATRIPLEX CANESCENS.

Abstract

Two water parameters were studied in this work, in conjunction with tolerance to salt stress, ie the turgor and transpiration in young plants of Atriplex halimus and Atriplex canescens. We determined the relative water content (RWC or TRE) or turgor and water loss through transpiration (RWL). For this, we tested the action of salts combined NaCl + CaCl 2 at 400 and 600 meq. The results after a week of stress, show that: the salinity has a highly significant effect on both species, characterized by a reduction in turgor and transpiration. However, this reduction is more pronounced as A.halimus than A. canescens. Moreover, whatever the parameter studied (turgor, transpiration, leaf area, stomatal density) values are increased in the presence of the nutrient solution alone. If the salt concentration exceeds 400 meq salts combined, either for A. halimus or A. canescens, these parameters decrease and the salt becomes harmful. The results also showed the existence of a close relationship between these parameters. Thus, when the relative water content (RWC) decreases, there is a gradual decrease in water loss (RWL) transpiration, characterized by closure of stomata.