中早熟马铃薯品种(系)遗传多样性ISSR分析

【目的】采用ISSR分子标记研究中早熟马铃薯品种(系)的亲缘关系及遗传多样性,为南方冬作区中早熟马铃薯育种亲本选择提供参考。【方法】利用筛选的8条ISSR引物,对33份广西各地应用的马铃薯品种(系)进行遗传多样性分析。【结果】8条引物共扩增出46条条带,其中有29条呈多态性,平均多态性带比率为63.0%。33份马铃薯品种(系)的遗传相似系数在0.63045~1.00000,平均相似系数为0.80967。聚类分析结果表明,在相似系数0.79000附近,33份马铃薯品种(系)可分为四大类,第一大类有4个品种(系),分别是DE03-34-6、JL03-786、中薯19号和中薯18号;第二大类仅有中薯6号;第三大类包括龙脊1号和DE03-79-1两个品种(系);余下的26份品种(系)聚为第四大类。在分类中,部分亲缘关系较近的品种如中薯13号和中薯14号、中薯18号和中薯19号可聚为较近的一类,说明ISSR分子标记能够正确地按马铃薯的亲缘关系进行分类。【结论】供试马铃薯品种(系)间存在较丰富的遗传多样性,可根据聚类分析结果中的遗传距离选择亲本,为南方冬作区中早熟马铃薯育种亲本的选择和杂种优势利用提供参考。

Genetic diversity analysis of early and middle maturity potato varieties (strains) using ISSR markers

Objective] Genetic relationship and diversity of early and middle maturity potato varieties (strains) were studied using ISSR markers in order to provide references for early and middle maturity potato breeding parent selection in southern winter-cropping areas. Method]Eight screening ISSR primers were used to assess the genetic diversity among 33 potato varieties (strains) planted in different areas of Guangxi.Result]The results showed that 8 primers amplified 46 bands, out of which 29 bands were polymorphic, and the percentage of polymorphic loci was 63.0%. Genetic similarity coefficient of 33 potato varieties (strains) changed from 0.63045 to 1.00000, with an average of 0.80967. Cluster analysis results indicated that the potato varieties (strains) could be classified into four groups at 0.79000 similarity level. The first group included DE03-34-6, JL03-786, Zhongshu 19 and Zhongshu 18. Only Zhongshu 6 was in the second group. The third group contained Longji 1 and DE03-79-1. The rest varieties (strains) were clustered into the fourth subgroups. Varieties with close affinity (like Zhongshu 13&Zhongshu 14, Zhongshu 18&Zhongshu 19) could be clustered into close groups, which meant that potato va-rieties could be precisely clustered using ISSR markers. Conclusion]The tested 33 potato varieties (strains) have abundant genetic diversity. Parents can be selected by genetic distances of cluster analysis, which could provide references for early and middle maturity potato breeding parent selection and heterosis utilization in southern winter-cropping areas.