基于穗粒重的甜高粱耐旱性全基因组关联分析  

Genome-wide association analysis of drought tolerance of sweet sorghum based on grain weight

作　　者：高丽娜 杨斌[1] 金志琴 胡文明 徐翠莲 GAO Lina;YANG Bin;JIN Zhiqin;HU Wenming;XU Cuilian(College of Agronomy,Tarim University,Alar,Xinjiang 843300)

机构地区：[1]塔里木大学农学院,新疆阿拉尔843300

出　　处：《塔里木大学学报》2023年第1期39-44,共6页Journal of Tarim University

基　　金：国家自然科学基金地区科学基金项目“甜高粱耐旱性评价及其与SSR标记的关联分析”(31660397);国家自然科学基金地区科学基金项目“基于多性状联合分析的甜高粱抗倒伏性状相关优异等位变异挖掘”(31660300)。

摘　　要：干旱是限制作物生产潜力的主要非生物因素。为解析甜高粱耐旱的分子机制,识别与耐旱性状关联的显著SNP位点,采用田间耐旱鉴定方法在甜高粱生育中后期进行水分控制,以400份甜高粱种质在干旱胁迫和正常滴灌条件下的穗粒重得出的耐胁迫指数作为表型数据,重测序获得的7079个SNP标记作为基因型数据,利用一般线性模型(GLM)和混合线性模型(MLM)分别进行全基因组关联分析。结果表明:分布在甜高粱第9号染色体和第10号染色体上的SNP数目相对较多;对SNP基因型数据进行主成分分析,从7079个SNP标记提取到两个主成分,第一主成分可将基因型分为两组;400份甜高粱种质穗粒重耐胁迫指数呈现右偏的正态分布;利用一般线性模型和混合线性模型的检测结果表明,两种模型均检测到9个显著的SNP位点,它们分别位于甜高粱第1,3,4,7,8和9号染色体以及3条super_1122染色体片段上,且具有相同的物理位置,并且两种方法检测到的SNP位点的变异碱基也无差异。两种模型对于甜高粱穗粒重在全基因组范围内检测结果较为一致,此结果可为甜高粱耐旱候选基因的挖掘和抗旱分子机理的研究奠定基础。Drought is a major abiotic factor limiting crop productivity.In order to understand the molecular mechanism of drought tolerance of sweet sorghum and identify significant loci associated with drought tolerance traits,the field drought tolerance identification was carried out in the middle and late growth stages of sweet sorghum by water control,and stress tolerance index obtained from the grain weight per spike of 400 sweet sorghum accessions under drought and drip irrigation conditions was used as phenotypic data,and 7079 SNP markers obtained by resequencing were used as genotype data for genome-wide association studies with gen-eral linear model(GLM)and mixed linear model(MLM)respectively.The results showed that the number of SNPs on the ninth and the tenth chromosome of sweet sorghum was the largest;two principal components were extracted through principal component analysis of 7079 SNPs genotype data,and genotype were divided into two groups by the first principal component;stress tolerance index of sweet sorghum based on grain weight per spike showed right-skewed normal distribution;the test results of general linear model and mixed linear model showed that 9 significant SNP loci were detected by two models,which located on chromosome 1,3,4,7,8,9 and three fragments of super_1122 with same positions,and there was no significant difference between variant bases tested by two methods.The test results were basically consistent with two models for grain weight per spike of sweet sorghum in the whole genome,which could lay a foundation for the mining of drought tolerance candidate genes of sweet sorghum and the research of crop drought resistance molecular mechanism.

关 键 词：甜高粱 穗粒重 耐胁迫指数 全基因组关联分析 

分 类 号：S514[农业科学—作物学]