利用SRAP和ISSR标记分析广东茶树种质资源的遗传多样性

ANALYSIS OF GENETIC DIVERSITY OF Camellia sinensis GERMPLASM IN GUANGDONG PROVINCE BY SRAP AND ISSR MARKERS

利用SRAP和ISSR 2种分子标记对25份广东茶树种质资源和不同地区5份对照品种的遗传多样性进行研究。结果表明,2种标记都能揭示材料间较高的遗传多样性,其中ISSR标记多态性又略高于SRAP标记。在SRAP分析中,每对引物组合可扩增出4～9条DNA片段,平均为6.05条;21对SRAP引物组合共扩增出127条DNA片段,其中114条具有多态性,多态性比率(PPB)为88.67%;材料间遗传相似系数GS变化范围为0.449～0.855,平均值为0.684。在ISSR分析中,每个引物可获得3～13条DNA片段,平均为6.93条;15个ISSR引物共扩增出104条DNA片段,其中101条具有多态性,多态性比率(PPB)为96.89%;材料间遗传相似系数GS变幅为0.115～0.886,平均达0.498。聚类分析表明,2种标记都能将供试材料完全区分开来,聚类结果具有一定的相似性,但也存在明显差异。Pearson相关分析表明,SRAP分析与ISSR分析的相关性达到显著性水平(r=0.1577,ρ<0.05)。

Genetic diversity in twenty-five local cultivars of Camellia sinensis in Guangdong province and five contrastive cultivars from different regions were assessed using sequence related amplified polymorphism（SRAP） and inter sinple sequence repeat（ISSR） makers for the first time,and the genetic relationship among Camellia sinensis accessions was revealed by cluster analysis at various levels.These results suggested that there was a high level of genetic diversity among Camellia sinensis germplasm,and ISSR makers were superior to SRAP.In SRAP analysis,a total of 127 bands were observed in 21 markers,among which 114 bands were polymorphic and the percentage of polymorphic bands（PPB） were 84.48%.Each primer could amplify 4 to 9 polymorphic bands with an average of 6.05 bands.Among the tea plant accessions,the SRAP-based genetic similarity（SRAP-GS） ranged from 0.449 to 0.855 with a mean of 0.684.In ISSR analysis,a total of 104 bands were detected,among which 101 bands were polymorphic and the PPB were 96.89%.The number of bands from each ISSR marker ranged from 3 to 13 with an average of 6.93.The ISSR-derived genetic similarity（ISSR-GS） ranged from 0.115 to 0.886 with a mean of 0.498.The cluster analysis indicated that all Camellia sinensis accessions could be distinguished by both SRAP and ISSR markers.Pearson test indicated that SRAP and ISSR markers were significantly associated（r = 0.1577,P ﹤ 0.05）.