摘要
矮秆资源是农作物矮化育种的物质基础,发掘矮秆基因资源对培育矮秆新品种具有重要作用。为了明确^(252)CF裂变快中子辐射诱变玉米自交系KWS49筛选得到的矮秆突变体20F421的遗传特性和矮化机理,以20F421为材料分别与玉米自交系PH6WC、B73、Mo17及KWS49杂交构建F_(1)和F_(2)分离群体,分析矮秆性状的遗传模式,并以(20F421/B73)F_(2)为定位群体,采用混池转录组测序(bulked segregant RNA-seq,BSR-seq)方法初步定位突变基因。结果表明,与KWS49相比,20F421的植株高度为95.2 cm,降低47.89%;穗位高度为23.9 cm,降低64.54%;茎秆节间长度显著缩短、叶片较直立密生,自交结实良好。遗传分析表明,F2分离群体野生型(高秆)与突变型(矮秆)植株性状分离比例符合3∶1,表明该突变体受单个核隐性基因控制;BSR-seq结果将突变基因定位在1号染色体177~255 Mb之间。通过与B73参考基因组进行比对发现,该区间内含有矮秆基因Br2,将20F421与br2突变体杂交进行等位性检测,F_(1)和F_(2)的株高均没有发生性状分离,表现为突变体20F421和br2表型,推测20F421的矮秆突变基因为矮秆基因Br2的等位突变。研究结果为进一步精细定位、克隆突变基因奠定基础,也为解析玉米矮化机理和培育矮秆玉米新品种提供重要基因资源和理论支撑。
Dwarf stem resources are the material basis for crop dwarf breeding,exploring dwarf stem gene resources is of great significance in breeding for dwarf crop cultivars.With the aim to clarifing the genetic characteristics and dwarf mechanism of a dwarf mutant 20F421 which was identified from radiation mutagenesis mutations using ^(252)CF fission fast neutrons using an elite maize inbred line KWS49,the dwarf stalk mutant 20F421 was as material to construct F_(1) and F_(2) isolated populations by hybridizing with maize inbred lines PH6WC,B73,Mo17 and KWS49,respectively,and analyzed the inheritance pattern of dwarf stalk traits,and used(20F421/B73)F_(2) as the localization population,and transcriptome sequencing combined with bulked segregant RNA-seq(BSR-seq)methods were used for initial mapping of mutant genes.The results showed that compared with KWS49,the plant height of 20F421 was 95.2 cm which reduced by 47.89%,the ear height was 23.9 cm which reduced by 64.54%,the internodes were significantly shortened,the leaves were more erect and dense,and the self-inbreeding was good.Genetic analysis showed that the separation rate of wild type(high stem)and mutant(dwarf stem)plant traits in the F2 isolated population conformed to the 3∶1,indicating that the mutant was controlled by a single nuclear recessive gene.The BSR-seq results map the mutant gene between chromosome 177~255 Mb.By comparing with the B73 reference genome,it was found that the interval contained the dwarf stalk gene Br2,so the allele detection of 20F421 and br2 mutant hybridization were detected,and the plant height of F_(1) and F_(2) did not have trait separation,showing the phenotypes of 20F421 and br2 mutant,and it was speculated that the dwarf stalk mutant gene in 20F421 was an allele mutation of the dwarf stalk gene Br2.The results of this study would lay a foundation for further fine localization and cloning of mutant genes,and also provide important genetic resources and theoretical support for the analysis of maize dwarf mechanism and the breed
作者
刘忠祥
周文期
李永生
王晓娟
杨彦忠
连晓荣
何海军
周玉乾
LIU Zhongxiang;ZHOU Wenqi;LI Yongsheng;WANG Xiaojuan;YANG Yanzhong;LIAN Xiaorong;HE Haijun;ZHOU Yuqian(Crops Research Institute,Gansu Academy of Agricultural Sciences,Lanzhou 730070,China)
出处
《中国农业科技导报》
CAS
CSCD
北大核心
2024年第6期22-29,共8页
Journal of Agricultural Science and Technology
基金
国家自然科学基金项目(32260473,31960406,32160490)
甘肃省重大专项(21ZD11NA005,21ZD10NF003)
甘肃省自然科学基金项目(20JR5RA110)
甘肃省农业科学院生物育种专项(2022GAAS04)。
关键词
玉米
矮杆
突变体
表型鉴定
遗传分析
maize
dwarf
mutants
phenotypic identification
genetic analysis
