杨梅基因组SSR引物的开发与应用

基于杨梅(Myrica rubar Sieb. et Zucc.)基因组序列信息,研究了1 431条scaffold中SSR位点的分布特点。共发掘到二至六核苷酸SSR位点43842个,分布在623条scaffold中,共有194种重复单元。二核苷酸SSR位点有36 383个,占总SSR的82.99%;AG/CT的出现频率最高,为55.70%,占总SSR位点的46.23%。三核苷酸SSR位点有6 115个,占总SSR的13.95%。四核苷酸SSR位点有827个,占1.89%。五核苷酸SSR位点为245个,占0.56%。六核苷酸SSR位点为272个,占0.62%。设计合成了59对基因组SSR引物,多态性分析显示,高度多态性引物26对,中度多态性引物为33对;将其应用于杨梅优株早鲜856及其他13个主栽品种的聚类分析,结果表明,上述引物在相似系数0.56处将14份杨梅材料分为两个群体,早鲜856与其他13个主栽品种在DNA水平上均存在差异,且与对照品种‘早色’的相似系数为0.86。

Development of Genomic SSR and Application in Chinese Bayberry

The distribution of simple sequence repeat（SSR）was studied in 1 431 scaffolds of Chinese bayberry（Myrica rubar Sieb. et Zucc.）genome. There were 43 842 SSR loci identified totally. And 194 kinds of repeating motifs that distributed in 623 scaffolds were discovered. The number and frequency of dinucleotide SSR loci were 36 383 and 82.99%. The frequency of AG/CT in dinucleotide was 55.70%，and in all SSR loci was 46.23%. It was indicated that AG/CT was the most common repeat motifs in Chinese bayberry genome. The number of trinucleotide SSR loci was 6 115，accounting for 13.95%. The number of tetranucleotide，pentanucleotide and hexanucleotide were 827，245 and 272 with the frequency 1.89%，0.56% and 0.62%，respectively. Meanwhile，59 pairs of Genomic SSR markers（gSSRs）were developed. After polymorphism analysis，26 gSSRs were highly polymorphic markers and 33 gSSRs were moderately polymorphic markers. In this study，the clustering analysis among the advanced selection Zaoxian 856 and the other 13 main cultivars were identified by all 59 gSSRs. According to the result，14 Chinese bayberry materials were clustered into two groups at the similarity coefficient of 0.56. It was illustrated that Zaoxian 856 was different from the other 13 varieties at the DNA level，and the similarity coefficient between Zaoxian 856 and control‘Zaose’was 0.86.