二棱大麦黄花叶病抗性种质的发掘、基因定位及育种利用研究

Barley yellow mosaic virus﹙BYMV﹚ is one of the main diseases affecting the production of barley. Recently, BYMV resistance in some two-rowed barley varieties decreased or lost in the middle and lower reaches of the Yangtze River basin due to the simplification of resistance sources and the variation of BYMV virus poison. It’s urgent to find new resistant source and breed new two–rowed barley variety with high resistance. In this study, comprehensive poisonous soil from Yangzhou and heavier infection poisonous soil form Linhai farm were used to infect the plants. Some key approaches, such as timing sowing, holding moisture by sprinkler irrigation in seeding stage, were conducted to ensure the uniformity of BYMV infection. The catalogue about the BYMV resistance in two-rowed winter barley will be scheduled by the identification of 1000 two-rowed barley. The new resistant source in two-rowed barley will be explored by genetic and pedigree analysis of resistant varieties. New resistance genes will be mapped using DH populations derived from new resistance lines × sensitive control line. Molecular markers linked to resistance genes in 180 two-rowed barley varieties were screened by GWAS using SSR and SNP markers. The technique system for breeding two-row barley with high BYMV resistance will be established, which integrates of convergent cross, molecular marker-assisted selection and resistance identification of BYMV.

大麦黄花叶病是影响大麦生产的重要病害之一。近年来，长江中下游流域因抗源单一及病毒毒系的变化，部分二棱大麦品种的黄花叶病抗性下降，甚至伤失，急需发掘新抗源，培育高抗病大麦黄花叶病的二棱品种。本研究利用毒系全的扬州毒土和病害重的临海毒土，采取适当早播、苗期喷灌保墒等技术，确保大田发病的均一，对1000份左右二棱大麦品种（系）的黄花叶病抗性进行系统鉴定，编制二棱冬大麦黄花叶病抗性目录；通过抗性材料的系谱分析和抗性遗传分析，发掘二棱大麦抗性新种质；构建抗性种质与感病对照的DH群体，定位新种质携带的抗性基因；选180个左右不同来源、不同抗性的二棱大麦组建自然群体，利用SSR和SNP分子标记构建遗传图谱，通过关联分析，筛选与不同抗性基因关联的分子标记；集成聚合杂交、分子标记辅助选择及黄花叶病抗性鉴定等技术，构建高抗大麦黄花叶病二棱大麦品种选育技术体系。

大麦是世界上第四大禾谷类作物，集啤用、食用和饲用于一体，啤用大麦多为二棱。大麦黄花叶病是一种土传性病毒病，主要危害冬大麦，可导致70-80%的减产，甚至绝收。培育抗病品种在生产上利用，是防止该病害对大麦生产有限的最经济有效的方法。本项目针对现有大麦黄花叶病抗性多来源与二棱大麦品种，开展了二棱冬大麦黄花叶病抗性种质的发掘、抗性基因的定位及育种利用研究。经多年多点鉴定，从2000多份来自国内外的大麦品种中鉴定到抗性稳定的大麦种质30份（扬农啤系列品种、扬饲麦系列品种、农科1-6、农科2-6、SY401等），对25个来源不同、抗感差异的大麦种质进行基因组重测序，对参试品种所携带的大麦黄花叶病抗性基因的等位性及单倍型进行分析，并根据单倍型进行了蕨类聚类分析，明确了不同抗性材料的抗性差异。通过对大麦重组自交系群体及DH群体的大麦黄花叶病抗性鉴定与遗传分析，初步认为抗病品种扬饲麦1号和扬农啤5号携带3个新的大麦黄花叶病抗性QTL位点，并筛选到紧密连锁的分子标记。通过遗传分析，初步确定抗病材料农科1-6携带1个新的大麦黄花叶病抗性基因。正在进行大麦黄花叶病抗性基因的精细定位及抗性形成的分子机理和调控网络研究。发表标注论文12篇，其中SCI论文5篇；制定发布农业农村部标准1个，申请发明专利2件，育成并登记2个高抗大麦黄花叶病的二棱啤酒大麦品种。