52份枇杷种质资源遗传多样性分析与DNA指纹图谱构建

Genetic diversity analysis and DNA fingerprint construction of 52 loquat germplasm resources

【目的】丰富枇杷种质资源鉴定方法,为枇杷种质资源发掘和利用提供理论依据。【方法】利用277对EST⁃SSR标记和1对果肉颜色相关InDel标记,对52份国内外枇杷种质资源和国家西南特色园艺作物种质资源圃(成都)枇杷育种与栽培创新团队创制的杂交后代进行遗传多样性分析并构建DNA指纹图谱。【结果】筛选出扩增带型清晰、稳定性和重复性好的9对引物,每对引物扩增条带为2~5条,平均85条;多态性条带比率为40.00%~100.00%,平均71.55%;多态性信息含量(PIC)为0.250~0.999,平均0.685。遗传多样性分析显示,52份枇杷种质资源和创制的杂交后代的平均相似系数为0.791;果肉颜色一致或地理分布相近的枇杷种质资源被聚类到相近的分类单元,并且可以准确地将西班牙、日本枇杷种质资源与其他种质资源进行区分。此外,本研究还构建了52份枇杷种质资源的DNA指纹图谱和色块矩阵。【结论】丰富了枇杷种质资源鉴定的分子标记,为今后发掘分子标记紧密连锁的功能基因或片段提供了理论依据。

【Objective】The study aimed to enrich the identification methods of loquat germplasm resources and provide theoretical basis for excavation and utilization loquat germplasm resources.【Method】Using 277 pairs of EST⁃SSR markers and 1 pair of InDel markers related to flesh color,the genetic diversity of 52 domestic and foreign loquat germplasm resources,including the hybrid offspring created by our re⁃search team were analyzed and DNA fingerprints were constructed.【Result】Nine pairs of primers with clear amplification bands,good stabil⁃ity and repeatability were screened out.Each pair of primers amplified 2-5 bands,with an average of 85 bands.The percentage of polymor⁃phic bands ranged from 40.00%to 100.00%,with an average of 71.55%.The polymorphism information content(PIC)was 0.250-0.999,with an average of 0.685.Genetic diversity analysis showed that the average similarity coefficients of all the 52 loquat germplasm re⁃sources and hybrid offspring were 0.791.Loquat germplasm resources with the same flesh color or similar geographic distribution was clustered into similar taxonomic units,which could accurately distinguish Spanish and Japanese loquat germplasm resources from other germplasm.In addition,DNA fingerprints and color block matrices of 52 loquat germplasm resources were constructed in the study.【Conclusion】The study enriches the molecular markers for the identification of loquat germplasm resources,and provides a theoretical basis for the future discovery of functional genes or fragments closely linked by molecular markers.