利用ISSR分析技术鉴定贵州枇杷新种质的研究

为探索枇杷新种质的鉴定方法，利用ISSR标记，构建了贵州18个枇杷栽培品种及课题组选育的7个优良新种质的DNA指纹图谱，并分析其相互间的亲缘关系。结果表明:以筛选出的15条引物进行PCR扩增，获得清晰、重复性好的谱带172条，其中多态性谱带157条，多态性比例为91.3%；应用3个引物825、834和848的组合，构建了25份枇杷品种（系）的ISSR指纹图谱，可以有效区分所有供试材料；聚类分析显示，在相似性系数为0.60时，可将供试种质分成2大类:一类主要为原产于浙江的品种（系），另一类主要为原产于四川的品种及选育的新种质；因此，ISSR标记能有效地用于枇杷栽培种及新种质的分子鉴定及其亲缘关系的解析。 

Identification of new germplasms of Guizhou loquat using ISSR markers

The fingerprinting and genetic relationship of 18 loquat(Eriobotrya japonica) cultivars,as well as the newly-bred lines were characterized by ISSR markers to explore the appraisal method of loquat germplasms.Fifteen selected ISSR primers were used for PCR amplification.The results showed that,a total of 172 bands with distinct and good repeatability were scored,among which 157 were polymorphic,and polymorphic rate was up to 91.3%.All of the tested cultivars (lines) might be highly distinguished by ISSR markers generated by combinations of primers 825,834 and 848.The genetic relationships of the tested genotypes were unraveled using UPGMA method based on the coefficient computed with ISSR markers,and two groups were obtained from dendrogram taking 0.60 as a threshold.Therefore,ISSR markers may be effectively employed to genotype the loquat germplasms,as well as to elucidate their genetic relationships.