| Abstract |
Yellow rust, caused by Puccinia striiformis f. sp. tritici, poses a severe threat to wheat (Triticum aestivum L.) production, necessitating the development of high-yielding, disease-resistant genotypes. This study aimed to enhance yellow rust resistance through hybridization and molecular techniques across three consecutive growing seasons (from2019/2020 to 2021/2022) at the Sakha Agricultural Research Station. The resistance genes Yr8, Yr15, Yr27, and Yr57 were introgressed from CIMMYT-derived monogenic lines into Egyptian cultivars Misr 2 and Gemmeiza 11. SSR markers confirmed successful gene introgression in BC₂ hybrids. Quantitative real-time PCR (qRT-PCR) analysis revealed elevated expression of defense-related genes (PAL, POX, Wheatwin1, Chitinase, and CYP), particularly in BC₂ generation, correlating with enhanced resistance. High-performance liquid chromatography (HPLC) identified key biochemical markers, including phosphatidylserine, oleic acid, β-carotene, and vitamin C, associated with disease resistance. Statistical analysis demonstrated a significant heterosis for yield-related traits, influenced by additive and non-additive genetic effects. Bioinformatics analysis predicted metal ion binding sites in resistance-associated proteins, highlighting their structural and functional importance. This integrated approach of molecular genetics, biochemical profiling, and bioinformatics provides a robust framework for breeding genetically stable, high-yielding wheat cultivars with enhanced yellow rust resistance, supporting sustainable wheat production in disease-prone regions. |
