Inherance For Wheat Stripe Rust Resistance Gene(S) Derived From Psathyrosthchys Huashanica Keng

Wheat stripe rust, caused by Puccinia striiformis f. sp. Tritici (Pst), is one of the mostdevastating diseases of wheat across the world, which could result in tremendous damage towheat productivity. Growing resistant cultivars is considered to be the most economic,effective and environmentally friendly method to control the disease. However, due to theunicity of resistance genes and high frequency of virulence variation, resistance of cultivarscould be easily overcome by the new races of stripe rust. Therefore, it is urgent to exploit andapply novel resistance genes in wheat productivity. As resistance genes in cultivated varietieswere restricted, many researchers turned to focus on wild relatives of wheat.Wheat-P. huashanica translocation line H9020-1-6-8-3was developed from thehybridization between donor parent P. huashanica accession0503383and receptor parent7182. Inheritance of resistance to stripe rust of H9020-1-6-8-3was systemically studied, andSSR markers of a resistance gene to CYR32were identified in the translocation line.Seedling test showed that H9020-1-6-8-3was resistant to eight races including CYR25,CYR29, CYR30, CYR31, CYR32, CYR33, Su11-4and Su11-11. To identify the resistancegene in H9020-1-6-8-3, F1, F2, F3and BC1of the cross Mingxian169/H9020-1-6-8-3wereinfected by CYR32during seedling stage. It indicated that the resistance to CYR32wasconferred by a single dominant gene, temporarily designated YrH9020a.The resistance gene was mapped by the F2population from Mingxian169/H9020-1-6-8-3.It was linked to six microsatellite markers, including Xbarc196, Xbarc202, Xbarc96,Xgpw4372, Xbarc21and Xgdm141, flanked by Xbarc96and Xbarc202with at4.5and8.3cM,respectively. Based on the chromosomal locations of these markers and the moleculardetection of Chinese Spring nullitetrasomic and ditelosomic lines, the gene was assigned tochromosome6DL.According to the origin, the molecular detection and the chromosomal location,YrH9020a might be a new resistance gene to stripe rust. The flanking markers linked toYrH9020a could be useful for marker-assisted selection in breeding programs.