24个菊芋品种(系)遗传多样性的ISSR标记分析

ISSR marker analysis on genetic diversity of twenty-four cultivars( lines) of Helianthus tuberosus

利用ISSR分子标记技术研究了来源于国内外不同区域的24个菊芋（Helianthus tuberosus Linn．）品种（系）的遗传多样性，并结合块茎特征采用聚类分析法探讨了它们的遗传关系。结果表明：用16条ISSR引物从24个品种（系）的基因组DNA共扩增出242条带，包含228条多态性条带，多态性条带百分率达94．2％，其中7条引物的多态性条带百分率达100．0％。各品种（系）间的遗传距离为0．19～1．01，遗传距离平均值为0．45。聚类分析结果显示：在遗传相似系数0．68处可将24个品种（系）划分为5类，第1类仅包含‘青芋1号’（‘Qingyu No．1’），第Ⅱ类仅包含W12，第Ⅲ类包含W30、W42、‘青芋2号’（‘Qingyu No．2’）、W09、W18、W26和WSl，第Ⅳ类包含W06和W84，第V类包含‘青芋3号’（‘Qingyu No．3’）、w23、W36、W43、W54、W75、WS0、W62、W64、W79、S150、S138和W66；多数块茎特征相似的品种（系）被聚在一起，但也有部分块茎特征不同的品种（系）被聚在同一类中；部分品种（系）的聚类分析结果与其形态分类结果及地理分布不一致。研究结果表明：供试的菊芋品种（系）具有较高的遗传多样性，存在着较为频繁的基因交流；基于ISSR标记分析能较准确地揭示出菊芋品种（系）间的遗传多样性。

Genetic diversity of twenty-four cultivars （lines） of Helianthus tuberosus Linn. from different regions at home and abroad was researched by ISSR molecular marker, and genetic relationship among these cultivars （lines） was discussed by cluster analysis method combined with tuber characteristics. The results show that 242 bands are amplified from genomic DNA of twenty-four cultivars （lines） by sixteen ISSR primers, and there are 228 polymorphic bands with percentage of polymorphic band of 94.2% , in which, the percentage of polymorphic band of seven primers reaches to 100.0%. The genetic distance among all cultivars （lines） is 0.19-1.01 with an average of 0.45. The cluster analysis result shows that twenty-four cuhivars （lines） can be divided into five groups at genetic similarity coefficient 0.68. I group only contains ＇ Qingyu No. Ⅰ, Ⅱ group only contains W12, m group contains W30, W42, ＇ Qingyu No. 2＇ , W09, W18, W26 and W51, group contains W06 and W84, and V group contains ＇Qingyu No. 3＇ , W23, W36, W43, W54, W75, W50, W62, W64, W79, S150, S138 and W66. Most cultivars （lines） with similar tuber characteristics are clustered together, but also some cuhivars （lines） with different tuber characteristics are clustered into the same groups. And cluster analysis result of a part of cultivars （lines） is inconsistent with morphological classification result and geographical distribution. It is suggested that cultivars （lines） of H. tuberosus tested possess higher genetic diversity, and there are frequent gene exchange. The genetic diversity of cuhivars （lines） of H. tuberosus can beaccurately revealed by means of ISSR marker analysis.