1.中国农业科学院作物科学研究所/作物基因资源与育种全国重点实验室,北京 100081;2.湖南省作物研究所,长沙 410125
研究方向为玉米种质资源,E-mail: 2402482400@qq.com;
石云素,研究方向为玉米种质资源,E-mail: shiyunsu@caas.cn
李永祥,研究方向为玉米种质资源,E-mail: liyongxiang@caas.cn
国家重点研发计划(2021YFD1200705, 2020YFE0202300);中国农业科学院作物科学研究所中央级公益性科研院所基本科研业务费专项(Y2020YJ09, CAAS-ZDRW202109);中国农业科学院科技创新工程
1.Institute of Crop Sciences, Chinese Academy of Agricultural Sciences/State Key Lab of Crop Gene Resource and Breeding, Beijing 100081;2.Hunan Crop Research Institute, Changsha 410125
Foundation projects: National Key R&D Program of China (2021YFD1200705, 2020YFE0202300);Fundamental Research Funds for Central Non-Profit of Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (Y2020YJ09, CAAS-ZDRW202109);Innovation Program of CAAS
籽粒相关性状包含粒长、粒宽和百粒重,是决定玉米产量的重要因素。本研究以玉米自交系B73与CML277构建的重组自交系群体为试验材料,应用基于测序的基因分型技术构建高精度遗传图谱,利用完备区间作图法鉴定到9个QTL,其中第2染色体上的qKW2.04位点分别解释粒宽和百粒重表型变异的20.34%和15.84%。在此基础上,利用轮回亲本B73及其近等基因导入系材料NIL-1041A构建F2分离群体,将qKW2.04位点进一步分解为2个紧密连锁的粒宽QTL,qKW2.04-1和qKW2.04-2,分别位于标记区间InDel23.32~umc1555和InDel47.09~InDel57.06,表型贡献率分别为22.45%和12.22%,增效等位变异均来自CML277。其中,通过筛选目标区段重组单株将qKW2.04-1精细定位在分子标记InDel26.76和InDel27.86间1.1 Mb区间之内。本研究为阐明玉米籽粒相关性状遗传基础提供了新的线索,为玉米高产分子设计育种提供了基因资源。
Kernel-related traits, including kernel length, kernel width, and hundred kernel weight, are pivotal factors in determining maize yield. In this study, a recombinant inbred line (RIL) population derived from the maize inbred lines B73 and CML277 was utilized as the experimental material. Based on the high-precision genetic maps constructed through genotyping-by-sequencing (GBS) technology, nine kernel-related quantitative trait loci (QTL) were identified. The major locus qKW2.04 was precisely located on chromosome 2 using the inclusive composite interval mapping (ICIM) method, explaining 20.34% and 15.84% of the phenotypic variation on grain width and 100-grain weight, respectively. In addition, an F2 segregating population was developed using the recurrent parent B73 and its introgression line (NIL-1041A) to further delimit qKW2.04. This locus was found with contribution due to two tightly linked kernel width major QTL, designated as qKW2.04-1 and qKW2.04-2, which were located in the marker intervals InDel23.32~umc1555 and InDel47.09~InDel57.06, explaining 22.45% and 12.22% of the phenotypic variation, respectively. The favorable allelic variations for both QTLs were contributed by CML277. Through the selection of recombinant individuals within the target region, qKW2.04-1 was finely positioned between molecular markers InDel26.76~InDel27.86 within a 1.1 Mb interval. This study provides new clues for elucidating the genetic basis of kernel-related traits and gene resources for high-yield molecular breeding in maize.
穆志生,汤彬,陈林,等.玉米籽粒相关性状遗传解析及主效位点