大豆蛋白含量新位点qPRO-19-1的定位

大豆是重要的粮食作物和经济作物,其籽粒蛋白约为40%,是植物蛋白的重要来源之一。国产大豆主要用于食用,提高大豆蛋白含量是主要的育种目标。因此,发掘大豆蛋白含量相关基因,对开发分子标记并培育高蛋白食用大豆具有重要意义。本研究以低蛋白大豆品种中黄35为母本,以源自日本的高蛋白大豆十胜长叶为父本,构建了重组自交系(RIL,recombination inbred lines)群体。利用集群分离分析法(BSA,bulked segregant analysis)在3条染色体筛选出9个与蛋白含量相关的SSR标记,其中位于19号染色体的QTL尚未见报道。进一步利用完备区间作图法(ICIM-ADD)分析RIL群体F_2:15和F_2:16,在19号染色体重复定位了1个蛋白质含量相关QTL qPRO-19-1,位于分子标记SSR_19_38和SSR_19_59之间,LOD值分别为3.43和3.98,贡献率分别为7.81%和14.87%,高蛋白等位基因来自于高蛋白亲本十胜长叶。qPRO-19-1的定位区间长度为385 kb,共有注释基因36个。本研究定位了蛋白质含量相关的新位点qPRO-19-1,为大豆高蛋白基因的图位克隆及分子标记育种奠定了基础。

Mapping of a New Quantitative Locus qPRO-19-1 Associated with Seed Crude Protein Content in Soybean(Glycine max L.)

Soybean is an economically-important food crop that contains about 40%of grain protein.The soybeans harvested from China are mainly used for food,and breeding for higher protein content is one of the main targets in soybean.Exploration of the genes related to soybean protein content and development of molecular markers are thus of great significance.In this study,a recombinant inbred line population was used by crossing a low protein soybean variety‘ZH35’(female parent)with the high protein accession‘Tokachi nagaha’(male parent)that was introduced from Japan.With the Bulked Segregant Analysis(BSA)analysis,nine SSR markers that associated to protein content were identified on three chromosomes,including chromosome 19 where no QTL was previously reported.This QTL qPRO-19-1 was allocated using an inclusive complete interval mapping method(ICIM-ADD)to the genetic interval of the molecular markers SSR1938 and SSR1959.This elite allele,which was derived from‘Tokachi Nagaha’,could explain 7.81%and 14.87%of phenotypic variations in F2:15 and F2:16 with the LOD values of 3.43 and 3.98,respectively.The physical interval of qPRO-19-1 expanded 385 kb that harbored 36 annotated genes.Collectively,the genetic mapping of the new QTL qPRO-19-1 laid the foundation for map-based cloning gene and molecular marker assisted breeding for high protein soybean varieties.