Physiological and molecular response under salinity stress in bread wheat (Triticum aestivum L.)

Wheat is among major cereals cultivated and consumed all over the world. However, production of wheat worldwide is affected by salinity stress. With reference to salt stress tolerance, though genetic variability exists in wheat gene pool, in depth understanding of molecular and physiological processes underlying salinity tolerance is lacking. Kharchia Local (KL), an Indian landrace of bread wheat (Triticum aestivum L.) is well known for its tolerance to salinity stress. Analysis of the expression pattern of an important vacuolar TaNHX1 (Na+(K+)/H+) antiporter gene in response to salt stress was carried out in two bread wheat genotypes viz. KL (tolerant) and HD 3086 (susceptible). This gene is associated with vacuolar Na+ sequestration. Changes in various physiological parameters in response to salt stress were also assayed in these genotypes. Physiological parameters such as RWC, MSI, CHL, Na+ and K+ contents in leaf and root tissues were estimated under both control and salt stress conditions. Higher transcript level of TaNHX1 gene in KL suggests early up regulation of this gene expression under salt stress. This study helps in understanding how various cellular response, differ in bread wheat in response to salt stress.