Characterization of salt tolerant wheat genotypes by using morpho-physiological, biochemical, and molecular analysis

Abstract

Food security is facing a major threat from salinity and there is a need to develop salt tolerant crop varieties to ensure that the demand for food from the world’s increasing population is met. Salinity mostly occurs in arid and semi-arid regions. It may cause many adverse physiological effects on plants, i.e., toxic ion accumulation, disturbed osmotic potential, and decreased crop yield. The present study aimed to investigate the morphological, physiological, biochemical, and genetic parameters of wheat genotypes under salt stress. Six wheat genotypes were screened for salt tolerance at the seedling and maturity stage. Seeds were sown at 0 and 150 mM of salinity level. Biochemical traits, i.e., shoot/root fresh and dry weight, chlorophyll a/b and total chlorophyll contents, shoot nitrogen, shoot phosphorus, proline, and carbohydrates were measured. Wheat genotypes showed a significant increase in free amino acids, shoot nitrogen, and total soluble proteins under saline conditions. Higher Na+/K+ ratio and free amino acids were estimated under 150 mM NaCl treatment in Pasban-90 and found to be the most salt-tolerant genotype. By contrast, reduced proline, total chlorophyll, and Na+/K+ ratio were found in Kohistan-97 marking it to be sensitive to stress. Expression analysis of HKTs genes was performed to validate the results of two contrasting genotypes. The differential expression of HKT2; 1 and HKT2; 3 explained the tissue and genotype specific epigenetic variations. Our findings indicated that these selected genotypes can be further used for molecular studies to find out QTLs/genes related to salinity. This suggests that, in contrasting wheat genotypes, there is a differentially induced defense response to salt stress, indicating a functional correlation between salt stress tolerance and differential expression pattern in wheat.

Silicon Induces Heat and Salinity Tolerance in Wheat by Increasing Antioxidant Activities, Photosynthetic Activity, Nutrient Homeostasis, and Osmo-Protectant Synthesis

“…The cultivar Akbar-2019 was heat tolerant, and it displayed better antioxidant activities, osmolyte accumulation, and nutrient uptake (Ca, Mg, and K), which resulted in better yields and yield traits in this cultivar. Our results are same as the findings of different authors, who also found that salt-tolerant cultivars displayed a better performance when compared to salt-sensitive cultivars [62,63].…”

Optimized leaf storage and photosynthetic nitrogen trade‐off promote synergistic increases in photosynthetic rate and photosynthetic nitrogen use efficiency

“…Amino acids are precursors or donors for many fundamental compounds and are also major organic N forms for N allocation and reuse. The storage of amino acids promotes rapid plant recovery from adversity (Irshad et al, 2022; Tavernier et al, 2007), but there is also energy consumption for turnover and N resource costs. Enhancing the source‐to‐sink transport of free amino acids in leaves accelerates N utilization and seed yield (Liu et al, 2020).…”

Integrating Agro-Morpho-Physiological Traits and SSR Markers for Detecting the Salt Tolerance of Advanced Spring Wheat Lines under Field Conditions

“…This approach is particularly useful in cases where candidate genes are unavailable. Among these markers, SSR markers serve as a potential tool for assessing the degree of genetic variation in salt tolerance in several crops [15,[31][32][33]46]. This approach offers numerous advantages that have already been mentioned in the Introduction section.…”

“…Additionally, they provide objective data that can be analyzed. Among the various molecular markers available for genetic characterization, simple sequence repeat (SSR) or microsatellite markers are extensively used for cultivar identification, germplasm characterization, genetic diversity, and molecular mapping due to their numerous advantages, including cost-effectiveness, the presence of multi-alleles, high levels of polymorphism, high-throughput capabilities, abundance, co-dominant, locus-specificity, informative, lack of bias, and repeatability [15,[31][32][33]. Therefore, SSR markers can play a vital role with phenotypic traits in evaluating the salt tolerance of wheat genotypes and identifying the most salt-tolerant ones.…”