马铃薯高世代选系疮痂病抗性评价及SSR辅助筛选

利用国外种质资源创造的20 份高世代马铃薯无性系为试材，以尤金为感病对照，克新18 号为抗病对照，采用自然 病圃和人工接种的鉴定方式进行疮痂病抗性评价，利用SSR 分子标记分析试材之间的亲缘关系，并对比SSR 遗传相似性系 数聚类结果和试材抗病性分类结果，探究利用SSR 分子标记辅助筛选疮痂病抗病资源的可行性。从试验地土壤和感病块茎 共分离纯化具有链霉菌特征的菌株278 份，其中240 份来自于块茎，38 份来自于土壤。具有致病力的菌株127 株，经鉴定 全部属于Streptomyces scabies 菌种。试材间的抗病性存在明显差异，可分为高抗、中抗、中感和高感4 个类型。人工接种与 自然病圃抗性鉴定结果存在极显著相关（R²=0.946 7）。抗病类型与感病类型通过SSR 遗传相似性系数聚类大致可以区分。

Scab Resistance Evaluation of Potato Advanced Generation and SSR-assisted Screening

Taking 20 potato advanced generation clones created by foreign germplasm resources as test material，‘Youjin’as susceptible contrast and‘Kexin No.18’ as resistant contrast，this paper evaluated the scab resistance of test material by natural infested field and artificial inoculation methods；analyzed the genetic relationship between test materials using SSR molecular markers；and compared the clustering results of SSR genetic similarity coefficient and classification results of disease resistance of the tested materials， so as to explore the feasibility of using SSR molecular marker for screening resources with scab resistance． Two hundred and seventy-eight bacterial strains with Streptomyces characteristics were separated and purified from soil and tuber，of which 240 from tuber and 38 from soil．One hundred and twenty-seven bacterial strains with pathogenicity were all identified as Streptomyces scabies．There were significant differences in disease resistance among the tested materials，which could be divided into 4 types：high resistant，moderate resistant，moderate susceptible and high susceptible．Correlation between artificial inoculation and resistance identification in natural disease nurseries was highly significant（R²=0.946 7）．The resistant type and susceptible type could be roughly distinguished by SSR genetic similarity coefficient clustering，indicating that scab resistance was related to the genetic relationship．