利用SSR分子标记分析三峡库区玉米地方品种的遗传关系  

Analysis of Genetic Diversity of Maize (Zea mays L.) Landraces in Three Gorges Reservoir Region Based on SSR Markers

作　　者：姚启伦[1] 姚成强[1] 

机构地区：[1]长江师范学院生命科学系,重庆涪陵408003

出　　处：《西南大学学报（自然科学版）》2007年第10期119-123,共5页Journal of Southwest University(Natural Science Edition)

基　　金：国家科技攻关计划资助项目(2004BA525B04);教育部"长江学者创新团队发展计划资助项目(IRT0453)

摘　　要：利用微卫星（SSR）标记技术和DNA混合取样方法，检测了来自三峡库区15个玉米地方品种的遗传多样性．42对SSR引物在15个玉米地方品种群体中共检测到248个多态性条带，每个位点的等位基因数为2～14个，平均5．9个；多态信息量0．28～0，81，平均为0．73；根据遗传相似系数矩阵做出的树状图，将15个玉米地方品种划分成3类，所有玉米地方品种间的遗传相似系数均在0．42以上．从15个玉米地方品种中选出5个，每个品种选取15个单株，共75个DNA单株样品，分析玉米地方品种群体的遗传结构．42对相同的SSR引物在5个玉米地方品种中检测到有效等位基因数Ae=3．40，平均期望杂合度He＝0．67．遗传结构分析结果表明，玉米地方品种群体间及群体内的遗传结构均偏离了Hardy-Weinberg平衡；品种群体内和群体间的遗传变异分别占总变异的92％和8％．The genetic diversity of 15 maize landraces from their geographic distribution area in the Sanxia dam area was tested, using 42 microsatellite （SSR） loci. A high genetic diversity was found among the landraces. At each locus, the number of alleles varied from 2 to 14, with an average of 5.9. The average polymorphism information content （PIC） was 0.73, ranging from 0.28 to 0.81. In addition, Clustering analysis divided them into 3 groups, and the genetic similarity coefficients between them were all over 0.42. Five landraces, each containing 15 individuals, were used to analyze the genetic structure on the basis of the same 42 SSR loci. Estimates of the effective allelic number （Ae） and expected heterozygosity （He） were 3.40 and 0.67, repectively. An obvious genetic differentiation from Hardy-Weinberg expectation was observed both within and among landraces. Intra-population genetic variation and inter-population genetic variation accounted for 92% and 98% of the total genetic variation of the landraces, respectively. The genetic diversity based on SSRs provides a guide for maize breeders to conserve and utilize the exclusive germplasm.

关 键 词：玉米地方品种 遗传多样性 SSR标记 三峡库区 

分 类 号：Q943[生物学—植物学]