不同类型甘薯品种遗传多样性的ISSR分析

为了丰富甘薯育成品种的遗传背景，筛选优良亲本，对来自全国各地的37份不同类型（鲜食型，淀粉型和兼用型等）的甘薯品种进行遗传多样性分析，选取的品种在薯皮、薯肉颜色方面有较大差异，采用ISSR分子标记对其多样性及亲缘关系进行分析。结果表明：100条引物中共筛选出19条ISSR多态性引物，共扩增出118条带，其中多态性条带115条，多态性位点频率为97.50%，供试甘薯品种的遗传距离介于0.04~0.36之间。台薯66和红东的遗传距离最近（0.04），观赏型甘薯紫罗兰与花青素加工型徐紫薯8号聚为一类。花青素加工型与菜用型和水果型的遗传距离较远，分别为0.43和0.40，与观赏型遗传关系最近（0.08）；水果型与其他8种类型遗传距离较远，均大于0.30，而鲜食型与其他类型的遗传距离均较近。分析了不同类型甘薯品种的遗传关系，相对于形态学标记，ISSR能较好地区分37份甘薯种质资源，其聚类分析结果能更客观地反映不同甘薯类型之间的遗传关系，可为不同用途品种选育的亲本选配提供参考。

Genetic Diversity Analysis of Different Characteristics of Sweetpotato Varieties by ISSR Molecular Marker

To broaden the genetic background and screen the excellent parents of sweetpotato cultivars， the genetic diversity of 37 sweetpotato from China were assessed by ISSR markers in this study. The results indicated that 19 highly efficient amplification primers were selected from 100 primers， and 118 of the total 115 bands amplified showed polymorphisms. The mean frequency of polymorphism was 97.50%. The genetic distance among the 37 varieties floated from 0.04 to 0.36. The genetic distance between Taishu 66 and Hongdong was the smallest （0.04）. Ziluolan （ornamental type） and Xuzishu 8 （anthocyanin process type） were clustered in the same group. Anthocyanin process type had the largest genetic distance to vegetable and fruit type （0.43 and 0.40， respectively）， which was the smallest nearest （0.08） to ornamental type. The fruit type was far from other types （>0.30）， however， the genetic distance between edible type and other types showed the opposite trend. The genetic relationships of different sweetpotato varieties were analyzed in this study. Related to these morphological markers，these 37 germplasm accessions could be clarified by ISSR. The molecular markers showed advantage in analysis of the genetic relationship among sweetpotato germplasm resources of different types. These results could provide reference for parents’ selection of varieties for different purposes.