Background: Wheat stripe rust (caused by Puccinia striiformis f. sp. Tritici), is a major disease that causes huge yield
damage. New pathogen races appeared in the last few years and caused a broke down in the resistant genotypes.
In Egypt, some of the resistant genotypes began to be susceptible to stripe rust in recent years. This situation
increases the need to produce new genotypes with durable resistance. Besides, looking for a new resistant source
from the available wheat genotypes all over the world help in enhancing the breeding programs.
Results: In the recent study, a set of 103-spring wheat genotypes from different fourteen countries were evaluated
to their field resistant to stripe rust for two years. These genotypes included 17 Egyptian genotypes from the old
and new cultivars. The 103-spring wheat genotypes were reported to be well adapted to the Egyptian
environmental conditions. Out of the tested genotypes, eight genotypes from four different countries were found
to be resistant in both years. Genotyping was carried out using genotyping-by-sequencing and a set of 26,703 SNPs
were used in the genome-wide association study. Five SNP markers, located on chromosomes 2A and 4A, were
found to be significantly associated with the resistance in both years. Three gene models associated with disease
resistance and underlying these significant SNPs were identified. One immune Iranian genotype, with the highest
number of different alleles from the most resistant Egyptian genotypes, was detected.
Conclusion: the high variation among the tested genotypes in their resistance to the Egyptian stripe rust race
confirming the possible improvement of stripe rust resistance in the Egyptian wheat genotypes. The identified five
SNP markers are stable and could be used in marker-assisted selection after validation in different genetic
backgrounds. Crossing between the immune Iranian genotype and the Egyptian genotypes will improve stripe rust
resistance in Egypt.