D.M. MAJEED, E.N. ISMAIL, F.R. AL-BURKI, A.S. ABED , and A.M.J. AL-JIBOURI
SUMMARY
Salinity is an abiotic stress factor and a major challenge that has significant negative effects on wheat production. It is also a source of concern for plant breeders leading them to reach reliable screening criteria for salt tolerance in wheat genotypes. The physiological analysis showed that the three salt-tolerant wheat genotypes viz., Dijla, 2H, and 3H showed the highest rate for the physiological traits i.e., chlorophyll content (38.9, 39.5, and 42.1, respectively),carbohydrates (600.14, 590.6, 560.8: 2H, 3H, and Dijla, respectively), proline acid (24.30, 23.14, and 21.87: Dijla, 3H, and 2H, respectively) under salt stress conditions, except protein percentage (3.8% and 3.3%: Rabia and Ibaa99, respectively) and K+/Na+ ratio (6.3 and 5.9: 2H and Dijla, respectively). The salt-tolerant wheat genotypes 2H, Dijla, and 3H enunciated an increased rate of expression of salt-related genes (TaOPR1 gene and β-actin gene) with values of 6.498, 4.0, and 3.768, respectively compared to two other salinity-sensitive cultivars i.e., Ibaa99 and Rabia under salt stress conditions. The salinity-sensitive cultivars i.e., Ibaa99 and Rabia showed no gene expression and significant difference with the control treatment after being treated with salinity stress conditions.
Keywords: wheat (Triticum aestivum L.), gene expression, TaOPR1 salt tolerance gene, salt-tolerant genotypes, chlorophyll, protein, carbohydrates, proline acid, K+/ Na+
Key findings: Under saline stress conditions, the genotypes of Dijla, 2H, and 3H showed the highest content of chlorophyll, protein (%), carbohydrate, and proline acid, except for K+/Na+ ratio, and excelled other wheat genotypes in gene expression (6.498, 4.0, and 3.768), respectively at the salt level of 16 dS/m. However, the salinity-sensitive wheat genotypes Ibaa99 and Rabia provided relatively low values for the expression of TaOPR1 gene expression associated with salt tolerance.
Date published: October 2022
DOI: http://doi.org/10.54910/sabrao2022.54.4.9