Antioxidant enzymes responses to NaCl stress in calli of four potato cultivars

摘要

The internode cuttings of 4 potato cultivars viz., Agria, Diamant Kennebec and Ajax grown in callus inducing media amended with 0, 50, 100 and 150 mM NaCl showed that callus growth of all the cultivars significantly decreased under salt stress. Superoxide dismutase (SOD) activity also decreased in all the cultivars when calli were grown in the presence of NaCl. However H2O2 detoxifying enzyme activities showed different results. Whereas ascorbate peroxidase (APOX) activity had decreasing pattern, peroxidase (POD) activity increased under salt stress. In high NaCl concentration these activities declined. Catalase (CAT) activity increased in potato cv. Agria and. Diamant and declined in cv. Kennebec and Ajax. On the other hand, under salt stress, changes in SOD and POD isozyme patterns at 100 mM NaCl were found more in terms of increased or decreased in isozymes activity as compared to control. The results showed that antioxidant enzymes have an important role in plant defensive systems against oxidative stress. Presumably some of the antioxidant enzymes have more protective role than the others.