Effect of NaCl-induced salinity stress was studied on three wheat (Triticum aestivum L.) genotypes (Platinum Lok 1, Eagle 135 and Kisan farmer). Seedling growth characteristics, chlorophyll contents, lipid peroxidation (MDA contents), proline, glycine betaine (GB) and the activities of catalase and peroxidase enzymes were evaluated at the seedling stage. The magnitude of reduction in growth parameters and chlorophyll contents was less in Platinum Lok 1 as compared to Kisan Farmer and Eagle 135. Platinum Lok 1 exhibited the highest increase in free proline and GB contents under NaCl stress as compared to the other two genotypes. Compared to Platinum Lok 1 and Eagle 135, Kisan Farmer accumulated more MDA contents under salinity stress. The enzyme activities were significantly higher in Platinum Lok 1 when compared to the other two genotypes. Therefore, these parameters could provide useful markers for the identification of salinity stress tolerant wheat genotypes at the seedling stage.
Keywords: Antioxidant enzymes; Glycine betaine; Proline; Reactive oxygen species; Salinity.