狗牙根抗寒相关性状与分子标记的关联分析

Association Analysis on Molecular Markers and Cold Tolerance Traits for Bermudagrass

利用152份狗牙根材料在抗寒性上的差异,采用关联分析的方法鉴定与抗寒性状关联的分子标记。结果表明,采用基于数学模型的聚类方法分析狗牙根遗传结构,当群体数目k=4时模型,后验概率LnP(D)最大并有比较稳定的α值,可将供试材料分开,存在亚群结构。利用SSR、EST-SSR分子标记对狗牙根基因组LD结构进行粗略估计,159个SSR、EST-SSR标记中共检测到6554个成对位点组合存在连锁不平衡,占所有可能成对位点组合的38.8%,其中237个成对位点组合存在较高程度的连锁不平衡(D′>0.5)。通过对遗传结构分析和调整,以各个个体相应的Q值作为协变量,对SSR位点变异进行分析,结果检测到11个位点(S24、S36、S27、S51、S59、S21、S110、S118、S105、S150、S158)的变异分别与抗寒性状相关(P<0.05)。

The differences in cold tolerance of 152 bermudagrass were applied to determine the molecular makers with cold tolerance by association analysis.The results showed that the clustering method based on mathematics model were used to investigate the genetic strucutre of bermudagrass,when the poputation number was k =4,posterior probability LnP（D）reached the biggest and owned the most stable a value,which can separate tested materials from each other,which were changed into sub-structrue.The molecular makers of SSR,EST-SSR were applied to estimate bermudagrass genome structure LD.The total 6554 loci combinations were found from 159 SSR,EST-SSR makers,in which there were disequilibrium state,which reached 38.8% of all probable combined loci,among which there were 237 combined loci with high extent of disequilibrium（D′0.5）,analysis and adjusting the genetic structure were conducted,and Q value,SSR loci variances were analyzed.The results indicated that the ariances of 11 loci such as S24,S36,S27,S51,S59,S21,S110,S118,S105,S150 and S158were associated with cold tolerance.