Investigation of biochemical and molecular changes in wheat genotypes under alkaline salt stress

Abstract

Wheat, a glycophyte plant that is the main staple food for the majority of the world’s population, is considerably sensitive to salinity and alkalinity stress. The goal of this study was to investigate antioxidant enzyme activity and elemental analyses to determine the response of three wheat genotypes to alkaline stress during the early development period as well as to examine DNA damage caused by alkaline stress using the inter simple sequence repeats (ISSR) molecular markers. The results demonstrated that NaHCO₃ treatments affected the amount and ratio of Na and K in all genotypes’ roots and leaves. Furthermore, NaHCO₃ treatment had a significant impact on H₂O₂ contents and malondialdehyde (MDA) levels of genotypes which exhibited varying abilities to reduce reactive oxygen species-induced damage and stress severity affected enzymatic antioxidant systems (SOD, CAT, and POD activities). The ISSR results revealed that genomic template stability rates decreased in response to alkaline stress. Overall, the data revealed significant genotype by alkaline salt exposure interaction, indicating that genetic response to alkaline salt stress may be different with respect to cultivars. In our study, cv. Çetinel 2000 had more enzymatic and non-enzymatic activity compared to cv. Aytin-98 and Tir genotypes under concentrations NaHCO₃ concentration, while latter two genotypes varied responses under the different concentrations. Our research also showed that genetic variability does exist in wheat for alkaline salt tolerant/resistant genes, further research using transcriptomic techniques is required to establish the gene expression profiles of wheat genotypes under such stress conditions to assess the genetic information about the related genes.