Differential response of two scented indica rice (Oryza sativa) cultivars under salt stress

Present report deals with the effect of varying (0 - 200 mM NaCl) salt stress on two popular scented non-basmati type indica rice cultivars, namely Indrayani and Ambemohar on germination and growth and biochemical parameters. In the present investigation the effect of increasing salt stress was seen on germination, biomass production and biochemical parameters including total protein content, proline accumulation, starch content, polyphenols levels, and reducing and non-reducing sugars. Contrasting behavior was evidenced in both the cultivars in terms of germination rate and biomass production at seedling and early vegetative growth level. Salt stress-induced proline accumulation was observed in both the cultivars, however, with much higher extent of proline accumulation in Ambemohar than Indrayani. A salinity stress of 200 mM NaCl resulted into 305% higher proline content than the control plants of Ambemohar against 222% higher proline in Indrayani at the same stress level. Similarly protein content was also higher in Ambemohar than Indrayani at the highest stress level used in this study. Contrasting results were seen in terms of starch content amongst both the cultivars, where continuous decrease with increasing salt stress was observed in Indrayani, on the other hand, an increase in starch content was evident in Ambemohar under the influence of NaCl-induced salt stress. These finding clearly indicates the comparably higher salt tolerant nature of Ambemohar than Indrayani which might be attributed to higher proline, protein and starch content than Indrayani cultivar under salt stress.