Liu Demei, Yuan Chan, Singh Ravi P, Randhawa Mandeep S, Bhavani Sridhar, Kumar Uttam, Huerta-Espino Julio, Lagudah Evans, Lan Caixia
Qinghai Provincial Key Laboratory of Crop Molecular Breeding, Laboratory for Research and Utilization of Qinghai Tibet Plateau Germplasm Resources, Northwest Institute of Plateau Biology, Innovation Academy for Seed Design Chinese Academy of Sciences (CAS), Xining, China.
Hongshan Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China.
Front Plant Sci. 2022 Aug 19;13:880138. doi: 10.3389/fpls.2022.880138. eCollection 2022.
Developing wheat varieties with durable resistance is a core objective of the International Maize and Wheat Improvement Center (CIMMYT) and many other breeding programs worldwide. The CIMMYT advanced wheat line "Mucuy" displayed high levels of resistance to stripe rust (YR) and leaf rust (LR) in field evaluations in Mexico and several other countries. To determine the genetic basis of YR and LR resistance, 138 F recombinant inbred lines (RILs) derived from the cross of Apav#1× Mucuy were phenotyped for YR responses from 2015 to 2020 at field sites in India, Kenya, and Mexico, and LR in Mexico. Seedling phenotyping for YR and LR responses was conducted in the greenhouse in Mexico using the same predominant races as in field trials. Using 12,681 polymorphic molecular markers from the DArT, SNP, and SSR genotyping platforms, we constructed genetic linkage maps and QTL analyses that detected seven YR and four LR resistance loci. Among these, a co-located YR/LR resistance loci was identified as , and a seedling stripe rust resistance gene was mapped on the 2AS/2NS translocation. This fragment also conferred moderate adult plant resistance (APR) under all Mexican field environments and in one season in Kenya. Field trial phenotyping with -virulent races indicated the presence of an APR QTL accounting for 18.3-25.5% of the LR severity variation, in addition to a novel YR resistance QTL, , derived from Mucuy. We developed breeder-friendly KASP and indel molecular markers respectively for / and . The current study validated the presence of known genes and identified new resistance loci, a QTL combination effect, and flanking markers to facilitate accelerated breeding for genetically complex, durable rust resistance.
培育具有持久抗性的小麦品种是国际玉米和小麦改良中心（CIMMYT）以及全球许多其他育种项目的核心目标。CIMMYT的先进小麦品系“Mucuy”在墨西哥和其他几个国家的田间评估中表现出对条锈病（YR）和叶锈病（LR）的高抗性。为了确定对YR和LR抗性的遗传基础，对Apav#1×Mucuy杂交产生的138个F重组自交系（RIL）在2015年至2020年期间于印度、肯尼亚和墨西哥的田间地点进行了YR反应表型分析，并在墨西哥进行了LR反应表型分析。在墨西哥的温室中使用与田间试验相同的主要小种对YR和LR反应进行幼苗表型分析。利用来自DArT、SNP和SSR基因分型平台的12681个多态性分子标记，我们构建了遗传连锁图谱并进行QTL分析，检测到7个YR抗性位点和4个LR抗性位点。其中，一个共定位的YR/LR抗性位点被鉴定为[具体名称未给出]，一个幼苗条锈病抗性基因[具体名称未给出]被定位在2AS/2NS易位上。该片段在所有墨西哥田间环境和肯尼亚的一个季节中也赋予了中等水平的成株抗性（APR）。用[具体小种名称未给出]毒性小种进行的田间试验表型分析表明，除了源自Mucuy的一个新的YR抗性QTL[具体名称未给出]外，还存在一个占LR严重程度变异18.3 - 25.5%的APR QTL。我们分别为[具体名称未给出]和[具体名称未给出]开发了对育种者友好的KASP和插入/缺失分子标记。当前研究验证了已知基因的存在，鉴定了新的抗性位点、一个QTL组合效应以及侧翼标记，以促进对遗传复杂、持久锈病抗性的加速育种。
