Identification and Mapping of QTL for Stripe Rust Resistance in the Chinese Wheat Cultivar Shumai126.

Stripe rust, caused by f. sp. , is a damaging disease of wheat globally, and breeding resistant cultivars is the best control strategy. The Chinese winter wheat cultivar Shumai126 (SM126) exhibited strong resistance to f. sp. in the field for more than 10 years. The objective of this study was to identify and map quantitative trait loci (QTL) for resistance to stripe rust in a population of 154 recombinant inbred lines (RILs) derived from a cross between cultivars Taichang29 (TC29) and SM126. The RILs were tested in six field environments with a mixture of the Chinese prevalent races (CYR32, CYR33, CYR34, Zhong4, and HY46) of f. sp. and in growth chamber with race CYR34 and genotyped using the Wheat55K single nucleotide polymorphism (SNP) array. Six QTL were mapped on chromosomes 1BL, 2AS, 2AL, 6AS, 6BS, and 7BL, respectively. All QTL were contributed by SM126 except The and had major effects, explaining 27.00 to 39.91% and 11.89 to 17.11% of phenotypic variances, which may correspond to known resistance genes and , respectively. The , , and with minor effects are likely novel. was only detected based on growth chamber seedling data. Additive effects were detected for the combination of , , and . SNP markers linked to ( and ) and ( and -) were converted to breeder-friendly Kompetitive allele-specific PCR (KASP) markers that would facilitate the deployment of stripe rust resistance genes in wheat breeding.