32份广东桑类型桑树种质资源亲缘关系的SRAP标记分析

广东桑类型是由分布在广西壮族自治区和广东省的广东桑种形成的桑树栽培类型。利用相关序列扩增多态性(SRAP)分子标记技术,对两广地区的部分广东桑类型桑树种质资源的亲缘关系进行分析,为地方桑树种质资源的遗传多样性保护和利用提供依据。选用22对SRAP引物组合在32份桑树种质材料中共扩增出144条带,其中有44条多态性带,多态性比率30.56%,平均每对引物组合扩增出2条多态性带。32份桑树种质材料间的遗传相似系数值变化范围为0.826 4～1.000 0,平均值0.894 4,说明供试广东桑类型桑树种质材料间存在较高遗传变异。采用UPGMA法进行聚类分析,将32份桑树种质材料划分成3类:第Ⅰ类包括了20份来自广西的地方品种资源,第Ⅱ类包括了3份来自广东的选育品种资源和7份来自广西的选育品种资源,第Ⅲ类的2份种质资源分别来自广西和广东。同一类群的各亚类群又多以同一地理来源的品种或亲本有相近、相同血缘的品种聚集。研究结果说明SRAP标记能很好地揭示同一桑种不同种质材料间的遗传多样性和亲缘关系,广东桑类型桑树种质资源的遗传多样性与地理来源有密切关系。

Phylogenetic Relationship of 32 Mulberry Germplasm Resources of Morus atropurpurea Revealed by SRAP Marker

Guangdong mulberry cultivars belong to mulberry species formed from Morus atropurpurea which are widely distributed in Guangxi Zhuang Autonomous Region and Guangdong Province.In order to provide reference for protection and utilization of genetic diversity of local mulberry germplasm resources,an analysis on phylogenetic relationship was conducted to some of the mulberry germplasm resources of Morus atropurpurea distributed in Guangxi and Guangdong areas by utilizing sequence-related amplified polymorphism(SRAP) technology.Using 22 primer pairs,144 bands were amplified from 32 mulberry germplasm materials,among which 44 bands were polymorphic,resulting in a polymorphic rate of 30.56%.On average,each primer combination had amplified 2 polymorphic bands.The genetic similarity coefficients of all 32 mulberry germplasm materials ranged from 0.826 4 to 1.000 0,with an average of 0.894 4,indicating that relatively higher genetic diversity exists between these mulberry germplasm materials of Morus atropur-purea.Clustering analysis by UPGMA method divided the 32 mulberry germplasm materials into 3 groups: group Ⅰ included 20 local variety resources from Guangxi,group Ⅱ included 3 and 7 variety resources which were bred in Guangdong and Guangxi respectively,and group Ⅲ included other 2 germplasm resources from Guangxi and Guangdong.Within the same group,various sub-groups were formed by clustered varieties with the same geographical origin or with close or identical blood relationship.These results indicated that SRAP markers are capable of revealing the genetic diversity and blood relationship between various germplasm materials of the same mulberry species,and that there is close relationship between genetic diversity and geographical origin in mulberry germplasm resources of Morus atropurpurea.