Identification and Molecular Mapping of the Rs Dm R Locus Conferring Resistance to Downy Mildew at Seedling Stage in Radish(Raphanus sativus L.)

作     者：XU Liang JIANG Qiu-wei WU Jian WANG Yan GONG Yi-qin WANG Xian-li Limera Cecilia LIU Li-wang 

作者机构：National Key Laboratory of Crop Genetics and Germplasm Enhancement/Engineering Research Center of Horticultural Crop Germplasm Enhancement and Utilization Ministry of Education/College of Horticulture Nanjing Agricultural University Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences 

出 版 物：《Journal of Integrative Agriculture》 (农业科学学报（英文版）)

年 卷 期：2014年第13卷第11期

页      面：2362-2369页

核心收录：

学科分类：09[农学] 0904[农学-植物保护] 090401[农学-植物病理学] 090402[农学-农业昆虫与害虫防治] 

基　　金：in part supported by grants from the National Key Technologies R&D Program of China (2012BAD02B01) the Key Technology R&D Program of Jiangsu Province, China (BE2013429) Jiangsu Agricultural Science and Technology Innovation Fund (JASTIF,CX(12) 2006,(13)2007],NAUNKL-ZW2009007 the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) 

主　　题：Raphanus sativus L. molecular mapping downy mildew seedling-stage resistance marker assisted selection 

摘      要：Downy mildew （DM）, caused by the fungus Peronospora parasitica, is a destructive disease of radish （Raphanus sativus L.） worldwide. Host resistance has been considered as an attractive and environmentally friendly approach to control the disease. However, the genetic mechanisms of resistance in radish to the pathogen remain unknown. To determine the inheritance of resistance to DM, F1, F2 and BC1F1 populations derived from reciprocal crosses between a resistant line NAU-dhp08 and a susceptible line NAU-qtbjq-06 were evaluated for their responses to DM at seedling stage. All F1 hybrid plants showed high resistance to DM and maternal effect was not detected. The segregation for resistant to susceptible individuals statistically iftted a 3：1 ratio in two F2 populations （F2（SR） and F2（RS））, and 1：1 ratio in two BC1F1 populations, indicating that resistance to DM at seedling stage in radish was controlled by a single dominant locus designated as RsDmR. A total of 1 972 primer pairs （1 036 SRAP, 628 RAPD, 126 RGA, 110 EST-SSR and 72 ISSR） were screened, and 36 were polymorphic between the resistant and susceptible bulks, and consequently used for genotyping individuals in the F2 population. Three markers （Em9/ga24370, NAUISSR826700 and Me7/em10400） linked to the RsDmR locus within a 10.0 cM distance were identiifed using bulked segregant analysis （BSA）. The SRAP marker Em9/ga24370 was the most tightly linked one with a distance of 2.3 cM to RsDmR. These markers tightly linked to the RsDmR locus would facilitate marker-assisted selection and resistance gene pyramiding in radish breeding programs.