日本落叶松EST-SSR标记开发及二代优树遗传多样性分析  

Development of EST-SSR Markers and Genetic Diversity Analysis of the Second Cycle Elite Population in Larix kaempferi

作　　者：杨秀艳[1] 孙晓梅[1] 张守攻[1] 谢允慧[1] 韩华[1] 

机构地区：[1]中国林业科学研究院林业研究所国家林业局林木培育重点实验室,北京100091

出　　处：《林业科学》2011年第11期52-58,共7页Scientia Silvae Sinicae

基　　金：国家"973"计划课题"速生优质林木的聚合育种与分子改良"(2009CB119107);中央级公益性科研院所基本科研业务费专项资金项目(RIF2010-08)

摘　　要：利用SSR标记研究选自第1代育种试验林、拟纳入二代育种群体的264株日本落叶松二代优树的遗传变异情况。利用1620条落叶松EST序列进行EST-SSR标记的开发,共发现58条序列中含有67个SSR位点,占全部EST序列的3.58%。获得7个多态性EST-SSR标记,其中5个在朝鲜落叶松、长白落叶松、兴安落叶松和华北落叶松中均可扩增出预期目标片段,且具有多态性,表明这些标记在落叶松属内的通用性良好。利用6个EST-SSR标记和4个gSSR标记对日本落叶松二代优树群体开展遗传多样性分析,每个位点的平均等位基因数为4.6个,有效等位基因平均数为3.1个。群体观察和期望杂合度均值分别为0.5902和0.5702;Nei's基因多样度和Shannon多样性指数分别为0.5691和1.0966;全部单株间遗传相似系数0.1725～0.9667。说明该二代优树群体的遗传多样性较高,具有构建二代育种群体的潜力。SSR markers were used to characterize the genetic variance and relationships among 264 elite genotypes of Japanese Larch （Larix kaempferi）, selected from the first-generation trials, which will be used as materials for second- generation breeding. A total 1 620 expressed sequence tags （ESTs） from larch were collected to develop simple sequence repeats （SSRs） by data mining. Totally 58 contigs with 67 SSRs were identified from all these contigs, and accounted for 3.58% of the total number of ESTs. Seven polymorphic simple sequence repeat （SSR） markers were developed and characterized; five of the loci had the advantage of high cross-species transferability to other larch species that naturally occur in China. These polymorphic and cross-taxon markers should be valuable for genetic studies on Larix. Six of these EST-SSR markers and four gSSR markers were used to detect genetic diversity of the elite population selected from the northern subtropical region. The average number of alleles and effective alleles per locus was 4.6 and 3.1, respectively. The means of expected and observed heterozygosities were 0. 590 2 and 0. 570 2, respectively. The genetic similarity coefficients between all elite tree individuals ranged from 0. 172 5 to 0. 966 7; Nei＇s gene diversity and Shannon＇s information index for this population were 0. 569 1 and 1. 096 6, respectively. The researeh suggests that these elite trees have good potential to establish second-generation breeding population with high genetic diversity.

关 键 词：日本落叶松 SSR EST-SSR 二代优树 遗传多样性 

分 类 号：S718.46[农业科学—林学] S718.54