陆地棉耐盐性状与SSR分子标记的关联分析

本研究以134份陆地棉栽培种为试验材料,测定其在0.3%盐浓度(质量分数)下的出苗率,并使用74对SSR引物对这些材料进行基因组变异扫描。利用Structure2.3.4软件分析该自然群体的遗传结构,在此基础上采用Tassel2.1软件对耐盐性状与SSR分子标记进行关联分析,寻找与棉花耐盐性状相关的分子标记。研究结果表明:(1)134份陆地棉栽培种的出苗率呈极显著差异,并筛选出27个盐敏感材料和10个耐盐材料。(2)74个SSR分子标记共检测出148个多态性位点,涉及246个等位变异,变异范围为2~7,平均每个标记3.32个;基因多样性指数变异范围为0.0295~0.4959,平均值为0.2897;SSR分子标记多态性信息含量(PIC)变幅为0.0290~0.3729,平均值为0.2381。(3)通过群体结构分析,将该自然群体划分2个亚群体,分别包含89份和45份材料。(4)关联分析共发现8个与棉花耐盐性状相关的SSR分子标记位点,表型变异解释率变幅为2.91%~7.82%,平均值为4.32%。此研究结果可以为棉花耐盐性状分子标记辅助选择育种提供参考。

Association Analysis of Salt Tolerance with SSR Markers in Gossypium hirsutum L.

In this study, 134 samples of upland cotton cultivars were selected. The seedling emergence rates were tested under NaCl stress at a concentration of 0.3%(mass fraction). SSR markers(74) were used to scan the genome of these materials. To find the SSR markers associated with salt tolerance, an association analysis between salt tolerance and SSR markers was performed using TASSEL 2.1, based on the analysis of genetic structure by Structure 2.3.4. The results showed the following. (1) The seedling emergence rates of 134 cultivars were significantly different, with 27 salt sensitive and 10 salt tolerant varieties identified. (2) One hundred forty-eight loci were found in 74 SSR markers involving 246 allelic variations, ranging from 2 to 7 with an average of 3.32 variations per SSR marker. The gene diversity ranged from 0.0295 to 0.4959 with a mean of 0.2897. The polymorphic information content ranged from 0.0290 to 0.3729 with a mean of 0.2381. (3) This natural population was classified into two subgroups by Structure 2.3.4. These two subgroups contained 89 and 45 samples, respectively. (4) Eight SSR sites associated with salt tolerance were found through association analysis, with the rate of explanation ranging from 2.91 to 7.82%, with a mean of 4.32%. The results could provide a reference for molecular marker assisted breeding of salt tolerance in cotton.