基于遗传多样性构建金针菇的核心种质群体及分子身份证

金针菇Flammulina filiformis是我国产量最高的工厂化栽培食用菌。为提高优良工厂化栽培金针菇种质的育种效率,本研究以国内外收集的105份金针菇种质为材料,开展体细胞不亲和评价,并采用SSR分子标记的方法对所有种质进行遗传多样性分析和聚类分析。20对SSR引物在105份种质中共扩增得到209个等位基因位点,所有种质间的遗传相似系数为0.71-1.00,在遗传距离0.76处可分为5个大类群。105份金针菇种质共包含67种不同的遗传背景,野生金针菇种质比栽培种质具有更丰富的遗传多样性。基于SSR的聚类分析结果和体细胞不亲和评价结果既相互印证,又可互为借鉴。本研究构建了包含44份金针菇种质的核心种质群体,占所有供试材料的41.90%,保留了100%等位基因。核心种质群体覆盖区域广泛,最大限度地保留了原始群体的遗传多样性和表型变异,可为育种的亲本选择提供参考。进一步构建了能同时反映每份金针菇种质SSR分子标记指纹图谱、收集地区、子实体颜色和栽培性状的分子身份证编码,并转换成可视二维码,为金针菇种质的高效标识和快速溯源提供了科学依据。

Construction of core collection and DNA fingerprinting of Flammulina filiformis based on genetic diversity analysis

Flammulina filiformis is the high yield industry-cultivated edible mushroom in China．In order to improve the breeding efficiency of industry-cultivated F. filiformis germplasm, a total of 105 F. filiformis cultivated strains collected from China and oversea was used to analyse the genetic diversity using somatic incompatibility evaluation and SSR molecular markers. A total of 209 loci was amplified from 105 germplasms using 20 pairs of SSR primers. The genetic similarity coefficient of the all germplasms was ranged from 0.71 to 1.00, and the germplasms was divided into five groups with genetic distance of 0.76. All the 105 germplasms represented 67 sets of different genetic patterns and the genetic diversity of wild-type germplasm was more divergent than that of cultivated germplasm. The results of SSR cluster analysis and somatic incompatibility evaluation were correlated. In this study, the core collection of 44 germplasms (41.90% of the total germplasms) was constructed and the alleles were retained at 100%. The core collection revealed the genetic diversity and phenotypic variation of the 105 germplasms, and could provide a reference for parent selection in future breeding programme. The information of SSR fingerprinting, collection site, fruiting body colour and cultivation traits for each germplasm were constructed in form of QR code for easy identification and traceability purposes.