AUTHOR=Wang Yuqi , Liang Fengying , Guan Fangnian , Yao Fangjie , Long Li , Zhao Xuyang , Duan Luyao , Wu Yu , Li Hao , Li Wei , Jiang Qiantao , Wei Yuming , Ma Jian , Qi Pengfei , Deng Mei , Zheng Youliang , Kang Houyang , Jiang Yunfeng , Chen Guoyue 

TITLE=Molecular Mapping and Analysis of an Excellent Quantitative Trait Loci Conferring Adult-Plant Resistance to Stripe Rust in Chinese Wheat Landrace Gaoxianguangtoumai

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.756557

DOI=10.3389/fpls.2021.756557

ISSN=1664-462X

ABSTRACT=<p>The Chinese wheat landrace “Gaoxianguangtoumai” (GX) has exhibited a high level of adult-plant resistance (APR) to stripe rust in the field for more than a decade. To reveal the genetic background for APR to stripe rust in GX, a set of 249 F<sub>6:8</sub> (F<sub>6</sub>, F<sub>7</sub>, and F<sub>8</sub>) recombinant inbred lines (RILs) was developed from a cross between GX and the susceptible cultivar “Taichung 29.” The parents and RILs were evaluated for disease severity at the adult-plant stage in the field by artificial inoculation with the currently predominant Chinese <italic>Puccinia striiformis</italic> f. sp. <italic>tritici</italic> races during three cropping seasons and genotyped using the Wheat 55K single-nucleotide polymorphism (SNP) array to construct a genetic map with 1,871 SNP markers finally. Two stable APR quantitative trait loci (QTL), <italic>QYr.GX-2AS</italic> and <italic>QYr.GX-7DS</italic> in GX, were detected on chromosomes 2AS and 7DS, which explained 15.5–27.0% and 11.5–13.5% of the total phenotypic variation, respectively. Compared with published <italic>Yr</italic> genes and QTL, <italic>QYr.GX-7DS</italic> and <italic>Yr18</italic> may be the same, whereas <italic>QYr.GX-2AS</italic> is likely to be novel. Haplotype analysis revealed that <italic>QYr.GX-2AS</italic> is likely to be rare which presents in 5.3% of the 325 surveyed Chinese wheat landraces. By analyzing a heterogeneous inbred family (HIF) population from a residual heterozygous plant in an F<sub>8</sub> generation of RIL, <italic>QYr.GX-2AS</italic> was further flanked by <italic>KP2A_36.85</italic> and <italic>KP2A_38.22</italic> with a physical distance of about 1.37Mb and co-segregated with the <italic>KP2A_37.09</italic>. Furthermore, three tightly linked Kompetitive allele-specific PCR (KASP) markers were highly polymorphic among 109 Chinese wheat cultivars. The results of this study can be used in wheat breeding for improving resistance to stripe rust.</p>