Metabolic changes and protein patterns associated with adaptation to salinity in Sesamum indicum cultivars.

Sesamum indicum is an important oil seed crop of semi-arid regions. Recently released cultivars of S. indicum were evaluated for their relative tolerance to sodium chloride (NaCl) salt. Salinity induced alterations in electrophoretic patterns of proteins and other metabolites were recorded in seeds germinated and grown in presence of different concentrations of sodium chloride (0.30, 50 and 70mM). Seedling growth was retarded in cv. RT-125 in presence of NaCl more than 30mM concentration. Control seedlings of cv. RT-46, RT-54 and RT-127 showed higher levels of total soluble sugars and sucrose as compared to cv. RT-125. Proline contents of control seedlings of cv. RT-127 was low as compared to other cultivars. Levels of soluble proteins were higher in RT-I25 and RT-127 than in RT-46 and RT-54 under all experimental conditions. However levels of sugars were higher in salt-treated cvs.RT-127. RT-46 and RT-54 as compared lo RT-125. Salt sensitive cultivar (RT-125), accumulated higher contents of malondialdehyde (MDA) and proline as compared to the others. On the other hand salt tolerant cultivars RT-54, RT-46 and RT-127 showed higher activity of superoxide-dismutase (SOD) and low MDA content as compared to RT-125. [ABSTRACT FROM AUTHOR]