Molecular and biochemical characterization of wheat resistance to yellow rust (Puccinia striiformis f. Sp. tritici) using SSR markers and antioxidant profiles

One of the most damaging foliar diseases of wheat in Egypt and around the world is yellow rust, often known as stripe rust, which is caused by Puccinia striiformis f. sp. tritici. This study aims to identify wheat cultivars resistant to yellow rust and to detect molecular markers linked to resistance. Two Egyptian bread wheat cultivars, Yr10 and Yr18 (highly resistant), and Gemmiza 11 and Shandweel 1 (susceptible), were evaluated. Four crosses and subsequent backcrosses between resistant and susceptible bread wheat genotypes were obtained. The phenolic content and antioxidant activity of the cultivars and their crosses under disease conditions were also measured for potential use in wheat breeding programs. The results showed that Gemmiza 11 and Shandweel 1 were highly susceptible and susceptible wheat cultivars, respectively. On the other hand, the two Yr monogenic lines (Yr10 and Yr18) showed high resistance against stripe rust. In addition, the cross between the susceptible cultivars and the resistant monogenic lines exhibited immunity and high resistance to Puccinia striiformis (Pst). The highest phenolic and flavonoid contents were recorded in the immune cultivars. In addition, all immune wheat cultivars exhibited higher levels of superoxide anion radical, hydroxyl radical, and nitric oxide radical scavenging activity. Out of thirteen SSR markers tested, seven were found to be associated with resistance to yellow rust. These markers may serve as the basis for marker-assisted selection programs aimed at enhancing wheat resistance to yellow rust.