Physiological responses to NaCl stress in three wild species of potato in vitro

In this study, responses of wild species of potato to NaCl stress were investigated in vitro. In S. stoloniferum and S. bulbosum, length of the shoot, fresh and dry weight, photosynthetic pigments, K ? concentration, K+/Na+ ratio, ascorbate pool, anthocyanin, and phenolic and flavonoid compounds were decreased in response to salinity. In these species, salinity increased the level of Na+, lipid peroxidation, proline and ion leakage percentage. In S. acaule, the length of the shoot, and fresh and dry weight were not affected by salinity. Photosynthetic pigments, Na+ concentration, proline, flavonoid and phenolic compounds quantities were increased and K+/Na+ ratio were decreased. K+ concentration, lipid peroxidation, ascorbate pool, anthocyanin and ion leakage were not changed by NaCl stress. Superoxide dismutase, guaiacol peroxidase, ascorbate peroxidase and catalase activities were increased in all species. The results suggest that the non-enzymatic antioxidant capacity in S. acaule (salt tolerant) is more important than the enzymatic antioxidant capacity in comparison with the other species.