Genetic diversity in wheat landraces for agronomic traits and yellow rust resistance

This study examined 74 wheat landraces collected from diverse regions, including Pakistan, Azerbaijan, Iran, Turkmenistan, Uzbekistan, and Kyrgyzstan, to assess morphological, yield, and disease resistance traits at Hazara University Mansehra. Significant variation was observed across traits such as days to heading, plant height, and grain yield. Principal Component Analysis (PCA) revealed that the first two principal components (PC1 and PC2) accounted for 48.59% of the variance, with PC1 strongly associated with grain yield and PC2 capturing variation related to productive tillers, plant height, and disease resistance. Cluster analysis categorized the landraces into distinct groups based on PCA scores, demonstrating substantial genetic diversity. Disease assessment for yellow or stripe rust identified a spectrum of resistance levels, from high resistance (0-TR) to susceptibility (CI = 60-80). PCR markers analysis of landraces with a 0-TR response uncovered the presence of resistance genes Yr-05, Yr-10, and Yr-15, enhancing our understanding of genetic resistance mechanisms. The study highlights the importance of utilizing diverse germplasm from different regions to capture a wide range of genetic variability which is crucial for breeding programs aimed at developing wheat cultivars with improved grain yield and disease resistance. By incorporating landraces with high resistance and diverse genetic backgrounds, particularly those carrying key resistance genes, the study supports the development of high-yielding and rust-resistant wheat cultivars, thus addressing future food security challenges and enhancing overall wheat production.