蒺藜苜蓿耐酸铝性状的全基因组关联分析

摘要

Aluminum (Al) toxicity is a major limiting factor of crop production in acidic soils,which make reduction of crop production every year.Medicago truncatula,a close relative of alfalfa,which is distributing in the world,is used as a source of genes to improve cultivated alfalfa (Medicago sativa).We screened 62 diverse M.truncatula accessions,conducted a genome-wide association (GWA) study using Al tolerance based on relative root growth.Fifty-eight SNPs associated with Al tolerance were identified by GWA analysis.These genes containing or neighboring to SNPs were annotated and analyzed.The results showed that they participated in cell wall,lipids metabolism,stress response process,redox regulation and small molecular transport.Using Al tolerance relative SNPs by genomic selection for predicting RRG (relative root growth) in M.truncatula accessions,and the predictive ability was estimated as 0.80.The results indicated that SNPs identified by GWA in this study could be used for improvement of Al tolerance in M.truncatula and M.sativa.%铝毒害是酸性土壤耕种的主要限制因素,每年造成大量作物减产.蒺藜苜蓿是紫花苜蓿的一年生近缘种,广泛分布于世界各地,是紫花苜蓿遗传改良的重要基因资源.本研究利用蒺藜苜蓿群体的耐酸铝性状差异,进行全基因组关联分析,筛选蒺藜苜蓿耐酸铝性状相关的遗传位点,共得到58个与蒺藜苜蓿耐酸铝性状相关的SNP标记.对其周围基因进行功能注释分析,发现这些SNP位点主要参与苜蓿的细胞壁、脂质代谢、环境胁迫响应过程、氧化还原反应过程以及小分子转运等过程.最后,通过基因组选择方法将发掘SNP标记应用到蒺藜苜蓿耐酸铝性状的预测,预测准确性达到0.80,这说明本研究发掘的SNP标记可以用于蒺藜苜蓿及其近缘物种紫花苜蓿耐酸铝性状的遗传改良.