Using reliable salt tolerance markers is a key component in barley breeding programs. In this study, physiological and antioxidative markers of two Tunisian barley salinity tolerance contrasting genotypes Boulifa (B) and Manzel Habib (MH) were assessed at 0, 3, 6 and 9 days of 200 mM salt treatment. Salinity caused decrease in growth, degraded photosynthetic activity and reduced water-holding capacity in both genotypes with more pronounced negative effects in the salt-sensitive (MH) compared to the salt-tolerant (B) genotype. On the other hand, the lower oxidative damage in B compared to MH under salt stress could be explained by higher activities of antioxidant enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione peroxidase (GPX) and glutathione reductase (GR). Additionally, a genotype-specific pattern of enzyme activity and corresponding gene expression was revealed in the two barleys under salt stress. In this context, a positive correlation was noted for the SOD. On the other hand, multivariate analysis marked SOD and APX as the most discriminating factors between both stressed genotypes. Our findings could be considered for selection in breeding programs for salt stress tolerance in barley.

使用可靠的耐盐性标记是大麦育种计划的关键组成部分。在这项研究中，在 200 mM 盐处理的第 0、3、6 和 9 天评估了两种突尼斯大麦耐盐性对比基因型 Boulifa (B) 和 Manzel Habib (MH) 的生理和抗氧化标志物。与耐盐（B）基因型相比，盐分导致两种基因型的生长减少、光合活性降低和持水能力降低，对盐敏感（MH）的负面影响更明显。另一方面，在盐胁迫下，与 MH 相比，B 中较低的氧化损伤可以解释为抗氧化酶活性较高，例如超氧化物歧化酶 (SOD)、抗坏血酸过氧化物酶 (APX)、谷胱甘肽过氧化物酶 (GPX) 和谷胱甘肽还原酶 (GR ）。此外，在盐胁迫下的两种大麦中揭示了酶活性和相应基因表达的基因型特异性模式。在这种情况下，SOD 呈正相关。另一方面，多变量分析将 SOD 和 APX 标记为两种压力基因型之间最具区分性的因素。我们的研究结果可以考虑在大麦耐盐胁迫的育种计划中进行选择。