全基因组关联分析定位水稻芽期中胚轴长度性状QTL  

Genome-wide Association Dissection for QTLs Controlling Mesocotyl Length Trait in Rice Bud Stage

作　　者：瞿媛 姚威 刘雄伦[1] 刘金灵[1] Qu Yuan;Yao Wei;Liu Xionglun;Liu Jinling(Hunan Provincial Key Laboratory of Crop Gene Engineering,Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China,College of Agronomy,Hunan Agricultural University,Changsha,410128)

机构地区：[1]湖南农业大学农学院,国家南方粮油作物协同创新中心,作物基因工程湖南省重点实验室,长沙410128

出　　处：《分子植物育种》2023年第3期858-865,共8页Molecular Plant Breeding

基　　金：作物种质创新与资源利用湖南省重点实验室科学基金项目(18KFXM01);国家自然科学基金项目(31972256)共同资助。

摘　　要：直播稻出苗难的问题是制约直播稻发展的重要因素之一,中胚轴的长度与直播稻大田出苗率和出苗质量密切相关。利用控制中胚轴伸长的基因培育长中胚轴品种是提高水稻直播稻出苗率和出苗质量的重要策略。为了挖掘长中胚轴水稻品种资源和鉴定控制中胚轴长度的基因,本研究以来源广泛的203份水稻核心种质为研究材料,评价了不同类型品种芽期中胚轴长度表型变异,利用全基因组关联分析(genome wide association analysis,GWAS)定位了控制中胚轴长度的QTL,并预测相关候选基因。结果表明,不同亚群材料中胚轴长度表型变异丰富,6个亚群平均长度为AUS稻(AUS)>温带粳稻(TEJ)>中间型(ADMIX)>籼稻(IND)>热带粳稻(TRJ)>香稻(AROMATIC)。GWAS分析定位了21个中胚轴长度相关QTL,共48个显著关联的SNP(P<0.001),分别位于第1、2、3、4、5、6和10染色体上。预测获得其中5个QTL区间的6个候选基因,编码松弛细胞壁、细胞伸长因子、生长素诱导等蛋白。研究结果为进一步克隆水稻中胚轴长度调控基因和利用分子标记辅助选择培育适宜长度中胚轴直播稻品种提供科学依据。The problem of rice seedling emergence is one of the important factors restricting the development of direct seeding rice.The length of mesocotyl is closely related to the seedling emergence rate and seedling quality of direct seeding rice.Breeding long mesocotyl varieties with genes that control mesocotyl elongation is an important strategy to improve the emergence rate and quality of direct-seeding rice.In order to mining the rice germplasms with long mesocotyl length from different ecotypes of rice cultivars,and identify the genes responsible for controlling the length of mesocotyl,203 rice cultivars from a core germplasm collection in the worldwide were used for evaluating the phenotypic variations of mesocotyl length,and mapping the QTLs controlling the length of mesocotyl with genome-wide association analysis(GWAS)method.The results revealed that the phenotype of mesocotyl length expresses a significantly abundant variation in six subpopulations.The average length of mesocot yl length in AUS rice was the largest,then the mesocotyl length of the other 5 subgroups was temperate japonica(TEJ)>intermediate(ADMIX)>indica(IND)>tropical japonica(TRJ)>AROMATIC.21 QTLs with 48 significantly associated SNPs(P<0.001)responsible for mesocotyl length were identified using GWAS analysis,which located on chromosomes 1,2,3,4,5,6 and 10,respectively.Six candidate genes in 5 QTLs intervals were predicted with the putative encoding proteins associated with the relaxed cell wall,cell elongation factor,and auxin induction.The results provided a scientific basis for further cloning of rice mesocotyl length regulation genes and breeding suitable mesocotyl length direct seeding rice varieties with molecular marker-assisted selection.

关 键 词：水稻 中胚轴长度 全基因组关联分析 数量性状位点 

分 类 号：S511[农业科学—作物学]