Characterization of a New Stripe Rust Resistance Gene on Chromosome 2StS from in Wheat.

Stripe rust, caused by f. sp. , is a highly destructive disease prevalent across most wheat-growing regions globally. The most effective strategy for combating this disease is through the exploitation of durable and robust resistance genes from the relatives of wheat. (Host) Barkworth and D.R. Dewey has been widely hybridized with common wheat and has been shown to be a valuable source of genes, conferring resistance and tolerance against both the biotic and abiotic stresses affecting wheat. In this study, a novel wheat- 2StS.2JL addition line, named Th93-1-6, which originated from wheat- partial amphidiploid line, Th24-19-5, was comprehensively characterized using nondenaturing-fluorescence hybridization (ND-FISH) and Oligo-FISH painting techniques. To detect plants with the transfer of resistance genes from Th93-1-6 to wheat chromosomes, 2384 M-M plants from the cross between Th93-1-6 and the susceptible wheat cultivar MY11 were studied by ND-FISH using multiple probes. A total of 37 types of 2StS.2JL chromosomal aberrations were identified. Subsequently, 12 homozygous lines were developed to construct a cytological bin map. Ten chromosomal bins on the 2StS.2JL chromosome were constructed based on 84 specific molecular markers. Among them, eight alien chromosome aberration lines, which all contained the bin 2StS-3, showed enhanced stripe rust resistance. Consequently, the gene(s) for stripe rust resistance was physically mapped to the 92.88-155.32 Mb region of 2StS in reference genome sequences v2.1. Moreover, these newly developed wheat- 2StS.2JL translocation lines are expected to serve as valuable genetic resources in the breeding of rust-resistant wheat cultivars.