پاسخ فيزيولوژيك گياه پنبه به شوري هاي مختلف خاك

Physiological response of cotton ( Gossypium hirsutum L. ) plants to soil salinity.

Effects of long term soil salinity was studied in cotton ( Gossypium hirsutum L.) cultivars , Siokra ( resistante) and Sahel (semi- resistante ) under four level of salinity [ EC=0.6 (control) EC=6.3, EC=12.3 and EC=16 dsm-1]. Salinity stress decreased stem and root length, organic material and chlorophylls (a, b, a+b) contents in both cultivars. Salinity induced increase in the content of proline, soluble sugars, and soluble proteins and also decrease in peroxidase activity were higher in siokra leaves significantly.In both cultivares Na+, Cl-, K+ concentration increased significantly in the leaves, indicating that salinity resistance was not associated with the ability of the plants restrict of ions uptake and accumulation.Na+ accumulation in Sahel was higher than Siokra.