海岛棉部分引进和自选品种遗传多样性的SRAP分析

Genetic diversity analysis of introduced and self-bred sea-island cotton (Gossypium barbadense L.) varieties based on SRAP markers

【目的】探讨海岛棉种质遗传多样性,为海岛棉种质资源的利用和优良品种的选育提供参考。【方法】利用相关序列扩增多态性(SRAP)分子标记技术对168份海岛棉材料进行遗传多态性分析,从224对引物组合中筛选出16对扩增条带清晰、多态性高的组合分析供试材料。【结果】共检测到129个多态性位点,每个引物组合扩增的位点数为3～12个,平均扩增位点8.06个。聚类分析结果表明,不同材料间的相似系数为0.27～0.89;在相似系数0.49水平上可将供试海岛棉材料分为4种类型,第1大类大部分是早期引进的国外品种,包括了埃及和中亚品种;第2大类包含了大部分新库系列和部分中亚品种,美国比马棉也聚在此类;第3大类主要包含了新海系列和部分中亚、苏联品种;第4大类仅有49(吉扎85)一个材料。【结论】海岛棉的相似系数变化幅度较大,材料差异较大,遗传多样性比较丰富。

[Objective]The present experiment was conducted to investigate the genetic diversity of sea-island cotton germplasm accessions and provide references for application of sea-island cotton germplasm accessions and breeding elite varieties. [Method]Sequence related amplified polymorphism （SRAP） marker technology was used to analyze genetic diversity of 168 sea-island cotton cultivars. Sixteen pairs of primer combinations with clear band and high polymorphism were selected from 224 pairs of primer combinations. [Result]In total, 129 polymorphic loci were detected by sixteen pairs of SRAP primers, and each primer combination amplified 3 to 12 loci with an average of 8.06 loci. UPGMA cluster analysis results showed that the genetic similarity coefficient of sea-island cotton accessions ranged from 0.27 to 0.89, and the 168 sea-island cotton germplasm accessions were divided into four groups at coefficient threshold of 0.49： the 1st group mainly involved introduced foreign varieties at early stage, which contained Egyptian and Central Asian varieties, the 2nd group mainly included a series of Xinku varieties, part of Central Asian varieties and American Pima varieties, the 3rd group mainly contained a series of Xinhai varieties, part of Central Asian varieties and Soviet Union varieties, the 4th group just only has Giza 85 in it. [Conclusion]The genetic similarity coefficient of sea-island cotton cultivars ranged widely, which showed great difference and rich genetic diversity among the 168 accessions.