三年桐EST-SSR标记的开发与种质遗传多样性分析  

Development of EST-SSR Markers and Their Use for Genetic Diversity Analysis in Tung Tree( Vernicia fordii( Hemsl. ) Airy Shaw)

作　　者：贾宝光[1] 林青[1] 谭晓风[1] 李泽[1] 龙洪旭[1] 向晖[1] 张琳[1] 

机构地区：[1]中南林业科技大学/经济林培育与保护省部共建教育部重点实验室/经济林育种与栽培国家林业局重点实验室/经济林培育与利用湖南省2011协同创新中心,湖南长沙410004

出　　处：《植物遗传资源学报》2016年第4期625-636,共12页Journal of Plant Genetic Resources

基　　金：国家林业公益性行业科研专项重点项目(201204403);国家"948"项目(2012-4-42)

摘　　要：以三年桐品种对年桐发育中的种子为材料,构建c DNA文库,获得3202个原始EST序列,经过去除冗余和低质量序列后,获得1047条非冗余单一序列,利用MISA软件从其中的173个非冗余EST序列中搜索得到212个SSR位点。其中,二核苷酸重复类型为主导（68.39%）,其次是三核苷酸重复类型（25.94%）,其优势基元为AG/CT（43.87%）、AT/AT（19.34%）和AGC/GCT（5.66%）。针对可设计引物的68个序列进行EST-SSR引物设计,结合PCR扩增和数据分析,鉴定出14对多态性标记,用该14对引物对169份三年桐种质资源进行遗传多样性检测,共得到41个等位基因（Na）,平均每对引物扩增出2.93个等位基因,期望杂合度（He）变幅为0.08~0.63,平均值为0.33,多态性信息含量（PIC）变幅为0.08~0.56,平均值为0.3,表明14对EST-SSR标记多态性较高,能较好地反映三年桐种质的遗传多样性。三年桐种质资源按群体进行非加权配对算术平均法（UPGMA）聚类分析,群体间的相似度变幅为0.9604~0.9986,遗传距离变幅为0.0022~0.0404,表明三年桐群体间的遗传多样性相对较低,亲缘关系较近。对169份三年桐种质资源个体进行聚类分析,结果显示不同地理种源的遗传关系缺乏明显的地理结构。The developing seeds of Tung tree（ Vernicia fordii（ Hemsl.） Airy Shaw） cultivar ‘Duiniantong＇ were used to construct the c DNA library and a total of 3202 original EST sequences were generated. After removing redundant and poor quality sequences,1047 non-redundant ESTs were detected to contain 212 SSRs by MISA. The dinucleotide and trinucleotide repeats were the most abundant SSRs,accounting for 68. 39% and 25. 94%,respectively. Furthermore,AG / CT was the most abundant repeat motif（ 43. 87%）,followed by AT / TA（ 19. 34%） and AGC /GCT（ 5. 66%）. A total of 68 EST-SSR primer pairs corresponding to 68 ESTs were designed,of which 14 were identified as polymorphic SSR markers by PCR and data analysis. Application of the 14 SSRs in genetics analysis of169 V. fordii accessions revealed that a total of 41 putative alleles were generated with a mean of 2. 93 alleles per locus. The expected heterozygosity（ He） and the polymorphism information content（ PIC） values ranged from 0. 08 to0. 63 and 0. 08 to 0. 56,with a mean of 0. 33 and 0. 3,respectively. The 14 EST-SSR markers exhibited a moderate level of polymorphism in V. fordii accessions. The genetic similarity coefficients and the genetic distances varied from0. 9604 to 0. 9986 and 0. 0022 to 0. 0404,respectively,indicating close genetic relationships among V. fordii populations. The genetic similarity-based dendrogram revealed that there was not a significant geographic pattern of genotypes across the collection areas of 169 V. fordii resouces.

关 键 词：三年桐 EST-SSR标记 多态性信息含量 遗传多样性 

分 类 号：S794.3[农业科学—林木遗传育种]