The role of nitrogen availability for the salt-tolerance of two different varieties of durum wheat.

Salt stress tolerance of durum wheat was assessed in control and 200 and 300 mM NaCl-exposed seed of two cultivars (BidiAP4 and Azizi). These salt treatments were accompanied by different levels of nitrate (Ca(NO3)2) added to the media (0.1, 3, 10 mM). The data showed that NaCl stress increased Na(+) and Cl(-) contents and lowered K(+) and NO3 (-) levels in seeds of BidiAP4 cultivar. In Azizi seeds exposed to NaCl, Na(+) and K(+) were highly accumulated while low levels of NO3 (-) and Cl(-) were detected. Those findings highlight the difference in the salt stress tolerance of these two durum wheat cultivars also depending on nitrogen (N) availability, Azizi cultivar being less sensitive to NaCl treatment than BidiAP4. These data also suggested a relationship between salt tolerance capacity and enhancement or maintenance of nitrogen and carbon metabolisms enzyme activity.