High Salt Induced Oxidative Damage and Antioxidant Response Differs in Nicotiana tabacum L. and Nicotiana rustica L. Cultivars

Abstract

We investigated effects of 10-day irrigation with 0.2M, 0.4M, and 0.6M NaCl on two tobacco variants cultivated in Turkey; Samsun (Nicotiana tabacum) and Hasankeyf (Nicotiana rustica). Salt treatments caused significant reduction in length, leafing, dry, and fresh weights together with a significant decline in relative water contents. Pigment levels decreased together with alterations in chlorophyll a/b and chlorophyll/carotenoid ratios. Anthocyanin levels and proline amount in roots increased. Malondialdehyde (MDA) and conductivity results indicated 0.6M NaCl induced damage in roots and leaves of Samsun. Since ascorbate peroxidase (APX) activity was higher in comparison to catalase (CAT), and increased whereas CAT activity decreased in response to salt treatment, APX seems to be more important in tobacco. Leaves and roots of cv. Samsun seems to be more effected by salt than Hasankeyf, whereas roots of Hasankeyf seems to have better adaptive responses against salt stress.