EFFECT OF SALT STRESS ON SOME PHYSIOLOGICAL PARAMETERS OF YOUNG PLANTS OF Atriplex halimus AND Atriplex canescens

Various hydric parameters were carried out during this work related to tolerance to saline stress at various levels, namely, turgor, sweating in young plants of Atriplex halimus and Atriplex canescens. We determined relative water content or turgor (RWC) and water loss through perspiration (RWL).

We tested the action of seawater at 50% and 100 as well as that of combined salts NaCl + CaCl2 at 400 and 600 meq. The results obtained after a week of stress show that salinity has a highly significant effect on both species, characterized by a reduction in turgor and sweating. However, this reduction is more marked in Atriplex halimus than Atriplex canescens. Moreover, these results also showed that whatever the parameter studied (turgor or transpiration, leaf area and stomatal density), the values increased in the presence of the nutrient solution alone. But as soon as the salt concentration exceeds 50% diluted seawater and 400 meq (combined salt) in Atriplex halimus and Atriplex canescens these parameters decrease and the salt becomes harmful. These parameters decrease and the salt becomes harmful. These results also further showed that there is a close relationship between these parameters. Thus, when the relative water content (RWC) decreases, there is a progressive reduction in the water loss (RWL) by transpiration.