Evaluating the Growth, Physiological and Biochemical Responses to Salinity Stress in Wheat (Triticum aestivum L.)
摘要
Crops’ optimal potential is realized in a stress-free environment, but they suffer many stresses; among them, salinity is the most critical stress, threatening crop yield and sustainability. Therefore, understanding these responses is crucial for developing salt-tolerant genotypes. In this study, four wheat genotypes, viz., C‑306, HD-2967, HD-2968, and WH-711, were grown under field conditions with RCBD (Randomized complete block design) and subjected to 0.25 d S m−1 NaCl salinity treatments for 30 days. Various growth, physiological, and biochemical parameters, including fresh weight (FW) and dry weight (DW), leaf-relative water content (RWC), proline content, chlorophyll (Chl) and carotenoid content (car), lipid peroxidase activity (LPO), total phenolic content (TPC) and total soluble carbohydrate (TSC) were measured. Results showed that the highest biomass was observed in HD-2968 (FW = 0.64 g, DW = 0.29 g) and lowest in HD-2967 (FW = 0.56 g, DW = 0.32 g) in control condition; however, in stress condition, WH-711 had highest values (FW = 0.22 g, DW = 0.08 g). This stimulation of growth parameters is associated with enhanced levels of different biochemical parameters such as chlorophyll, carotenoid, proline content, LPO, TSC, TPC, and RWC. Interestingly, all the genotypes showed reduced growth and alterations in physiological parameters under salinity stress compared to the control condition, but the magnitude of responses varied among the genotypes. The correlation matrix showed highly positive corrections for FW with proline (0.95), LPO (0.83), TSC (0.81), car (0.77) and Chl a (0.67); DW with SL (0.93), RWC (0.85), Chl b (0.83) Chl a (0.72), TPC (0.65) and car (0.60); SL with RWC (0.93), TPC (0.86), Chl a (0.73), Chl b (0.69), car (0.67), TSC (0.62) and LPO (0.50); Chl a with car (0.98), TSC (0.97), LPO (0.96), RWC (0.92), TSC (0.81); car with TSC (1.00), LPO (0.96) RWC (0.89) and proline (0.84); while RL was negatively associated with Chl b (0.42), proline (0.32) and LPO (0.24) under salinity. Based on their superior maintenance of RWC, chlorophyll, carotenoids, and increased proline, LPO, TSC, and TPC under salinity stress, genotypes C‑306 and WH-711 demonstrated higher salt tolerance and show promise for breeding salt-tolerant wheat genotypes.