First author: Biotechnology and Nuclear Technology Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan 610061, China; first, second, third, and sixth authors: Department of Plant Pathology, Washington State University, Pullman 99164-6430; first and fifth authors: Triticeae Research Institute, Sichuan Agricultural University, Northeast Road No. 555, Wenjiang, Chengdu, Sichuan 611130, China; third and sixth authors: U.S. Department of Agriculture, Agricultural Research Service, Wheat Health, Genetics, and Quality Research Unit, Pullman, WA 99164-6430; and fourth author: U.S. Department of Agriculture, Agricultural Research Service, Cereal Crops Research, Fargo, ND 58102-2775.
Phytopathology. 2018 Jun;108(6):737-747. doi: 10.1094/PHYTO-11-17-0375-R. Epub 2018 Apr 25.
Stripe rust, caused by Puccinia striiformis f. sp. tritici, is an important disease of wheat worldwide. Exploring new resistance genes is essential for breeding resistant wheat cultivars. PI 182103, a spring wheat landrace originally from Pakistan, has shown a high level of resistance to stripe rust in fields for many years, but genes for resistance to stripe rust in the variety have not been studied. To map the resistance gene(s) in PI 182103, 185 recombinant inbred lines (RILs) were developed from a cross with Avocet Susceptible (AvS). The RIL population was genotyped with simple sequence repeat (SSR) and single nucleotide polymorphism markers and tested with races PST-100 and PST-114 at the seedling stage under controlled greenhouse conditions and at the adult-plant stage in fields at Pullman and Mt. Vernon, Washington under natural infection by the stripe rust pathogen in 2011, 2012, and 2013. A total of five quantitative trait loci (QTL) were detected. QyrPI182103.wgp-2AS and QyrPI182103.wgp-3AL were detected at the seedling stage, QyrPI182103.wgp-4DL was detected only in Mt. Vernon field tests, and QyrPI182103.wgp-5BS was detected in both seedling and field tests. QyrPI182103.wgp-7BL was identified as a high-temperature adult-plant resistance gene and detected in all field tests. Interactions among the QTL were mostly additive, but some negative interactions were detected. The 7BL QTL was mapped in chromosomal bin 7BL 0.40 to 0.45 and identified as a new gene, permanently designated as Yr79. SSR markers Xbarc72 and Xwmc335 flanking the Yr79 locus were highly polymorphic in various wheat genotypes, indicating that the molecular markers are useful for incorporating the new gene for potentially durable stripe rust resistance into new wheat cultivars.
条锈病由条形柄锈菌小麦专化型引起，是全球范围内小麦的重要病害。探索新的抗性基因对于培育抗条锈病小麦品种至关重要。PI 182103 是一种源自巴基斯坦的春小麦地方品种，多年来在田间表现出对条锈病的高度抗性，但该品种中抗条锈病的基因尚未得到研究。为了定位 PI 182103 中的抗性基因，我们利用 Avocet 感病（AvS）与 PI 182103 杂交，培育了 185 个重组自交系（RIL）。利用简单重复序列（SSR）和单核苷酸多态性标记对 RIL 群体进行基因型分析，并在温室条件下幼苗期和 2011 年、2012 年和 2013 年在华盛顿州 Pullman 和 Mt. Vernon 田间成株期利用 PST-100 和 PST-114 对其进行接种鉴定。共检测到 5 个数量性状位点（QTL）。QyrPI182103.wgp-2AS 和 QyrPI182103.wgp-3AL 在幼苗期被检测到，QyrPI182103.wgp-4DL 仅在 Mt. Vernon 田间试验中被检测到，QyrPI182103.wgp-5BS 在幼苗期和田间试验中均被检测到。QyrPI182103.wgp-7BL 被鉴定为高温成株期抗性基因，在所有田间试验中均被检测到。QTL 之间的相互作用主要为加性，但也检测到一些负相互作用。7BL QTL 被定位在 7BL 染色体 bin 0.40 到 0.45 之间，并被命名为一个新基因，永久命名为 Yr79。Xbarc72 和 Xwmc335 等 SSR 标记在各种小麦基因型中高度多态性，表明这些分子标记可用于将新的抗条锈病基因 Yr79 导入新的小麦品种中，从而获得潜在持久的抗条锈病能力。
