摘要
玉米出苗率不仅受温度、水分等外部环境因素的影响,同时也受到内部遗传因素的控制,直接影响玉米产量,是玉米育种重要的目标性状之一。本研究利用一套以玉米野生近缘种大刍草(Zea mays ssp.Parviglumis Iltis&Doebley)为供体亲本,现代玉米自交系W22为受体亲本构建的包含866个家系的渗入系群体,结合均匀覆盖玉米全基因组的19838个SNP分子标记,采用R/qtl的多QTL模型对玉米出苗率进行高精度的QTL定位分析。结果共检测到3个控制玉米出苗率的QTL:qFGR4-1、qFGR5-1和qFGR8-1,分别位于第4、5和8染色体,两侧的分子标记分别为m20780与m21277、m29418与m29680、m44383与m44706。3个QTL共解释11.2%的表型变异,单个QTL表型贡献率的变幅为2.8%~4.8%,加性效应的变幅为4.5%~7.4%,表明玉米出苗率属于典型的数量性状,由微效多基因控制。3个QTL均来自W22的等位基因增加出苗率,表明玉米出苗率在玉米长期驯化和改良过程中可能受到定向选择。本研究为进一步解析玉米出苗率的遗传基础,克隆相关基因和通过分子标记辅助选择改良玉米出苗率提供了重要的参考价值。
The field germination rate of maize seeds,which is controlled by the genetic factors that interact with environmental factors(i.e.temperature,water),directly affects yield production and severs as one of the important targets in maize breeding.In this study,we performed a high-resolution QTL mapping for field germination rate using the multiple QTL model implemented in R/qtl.The introgression line population including 866 lines was derived from a cross between a maize inbred line W22 and a typical accession of teosinte,the wild progenitor of maize,followed by genotyping with 19,838 SNP markers.Three QTL were detected including qFGR4-1,qFGR5-1 and qFGR8-1,which were flanked by the markers m20780 and m21277 on chromosome 4,m29418 and m29680 on chromesome 5,as well as m44383 and m44706 on chromosome 8,respectively.Three loci attributed to 11.2%of the phenotypic variation,with the phenotypic contribution rate and additive effect of each QTL ranged from 2.8%to 4.8%and from 4.5%to 7.4%,respectively.These results indicated that the field germination rate is a typical quantitative trait,which is controlled by multiple micro-effect genes.In addition,the W22 alleles at three loci showed positive additive effects,suggesting that field germination rate might have experienced a directional selection during maize domestication and improvement.Collectively,this study might provide important reference for future elucidating the genetic basis of field germination rate,cloning key genes and improving field germination rate using molecular marker-assisted selection in maize.
作者
胡锦祥
肖仁杰
柳志华
朱雪晴
李芳
徐莹
罗红兵
黄成
HU Jin-xiang;XIAO Ren-jie;LIU Zhi-hua;ZHU Xue-qing;LI Fang;XU Ying;LUO Hong-bing;HUANG Cheng(College of Agronomy,Hunan Agricultural University,Changsha 410128;Maize Engineering Technology Research Center of Hunan Province,Changsha 410128;Hunan Provincial Key Laboratory for Germplasm Innovation and Utilization of Crop,Changsha 410128)
出处
《植物遗传资源学报》
CAS
CSCD
北大核心
2020年第6期1561-1567,共7页
Journal of Plant Genetic Resources
基金
湖南省教育厅优秀青年项目(18B117)
作物种质创新与资源利用重点实验室开放研究项目(19KFXM10)
湖南农业大学“双一流”学科建设项目(SYL2019004)。
关键词
玉米
大刍草
渗入系群体
出苗率
QTL定位
maize
teosinte
introgression line population
field germination rate
QTL mapping
