Ji Guisu, Zhang Qingjiang, Du Ruiheng, Lv Peng, Ma Xue, Fan Shu, Li Suying, Hou Shenglin, Han Yucui, Liu Guoqing
Institute of Millet Crops, Hebei Academy of Agricultural & Forestry Sciences/Hebei Branch of China National Sorghum Improvement Center, Shijiazhuang, 050035, China.
Institute of Cereal and Oil Crops, Hebei Academy of Agricultural & Forestry Sciences, Shijiazhuang, 050035, China.
BMC Genomics. 2017 Jan 7;18(1):51. doi: 10.1186/s12864-016-3430-7.
Sorghum is mainly used as a human food and beverage source, playing an important role in the production of ethanol and other bio-industrial products. Thus it is regarded as a model crop for energy plants. Genetic map construction is the foundation for marker-assisted selection and gene cloning. So far several sorghum linkage maps have been reported using different kinds of molecular markers. However marker numbers and chromosome coverage are limited. As a result, it is difficult to get consistent results and the maps are hard to unify. In the present study, the genomes of 130 individuals consisting an F population together with their parents were surveyed using a high-throughput sequencing technique. A high-density linkage map was constructed using specific-locus amplified fragments (SLAF) markers. This map can provide information and serve as a reference for effective gene exploration, and for marker assisted-breeding program.
A high-throughput sequencing method was adopted to screen SLAF markers with 130 F individuals from a cross between a grain sorghum variety, J204, and a sweet sorghum variety, Keter. In the present study, 52,928 suitable SLAF markers out of 43,528,021 pair-end reads were chosen to conduct genetic map construction, 12.0% of which were polymorphic. Among the 6353 polymorphic SLAF markers, 5829 (91.8%) were successfully genotyped in the F mapping population. Finally 2246 SLAF markers were obtained to construct a high-density genetic linkage map. The total distance of linkage map covering all 10 chromosomes was 2158.1 cM. The largest gap on each chromosome was 10.2 cM on average. The proportion of gaps less than and/or equal to 5.0 cM was averagely 98.1%. The markers on each chromosome ranged from 123 (chromosome 9) to 315 (chromosome 4) with a mean value of 224.6, the distance between adjacent markers ranged from 0.6 (chromosome 10) to 1.3 cM (chromosome 9) with an average distance of only 0.98 cM.
A high density sorghum genetic map was constructed in this study. The total length was 2158.1 cM covering all 10 chromosomes with a total number of 2246 SLAF markers. The construction of this map can provide detailed information for accurate gene localization and cloning and application of marker-assisted breeding.
高粱主要用作人类食品和饮料来源，在乙醇及其他生物工业产品生产中发挥着重要作用。因此，它被视为能源植物的模式作物。遗传图谱构建是分子标记辅助选择和基因克隆的基础。到目前为止，已经报道了几种使用不同类型分子标记构建的高粱连锁图谱。然而，标记数量和染色体覆盖范围有限。因此，难以获得一致的结果，且这些图谱难以统一。在本研究中，利用高通量测序技术对由130个个体组成的F群体及其亲本的基因组进行了检测。使用特异性位点扩增片段（SLAF）标记构建了高密度连锁图谱。该图谱可为有效的基因探索以及分子标记辅助育种计划提供信息并作为参考。
采用高通量测序方法，从粒用高粱品种J204和甜高粱品种Keter的杂交后代中筛选出130个F个体的SLAF标记。在本研究中，从43528021对末端 reads 中选择了52928个合适的SLAF标记进行遗传图谱构建，其中12.0%为多态性标记。在6353个多态性SLAF标记中，5829个（91.8%）在F作图群体中成功进行了基因分型。最终获得2246个SLAF标记构建了高密度遗传连锁图谱。覆盖所有10条染色体的连锁图谱总长度为2158.1 cM。每条染色体上最大的间隙平均为10.2 cM。间隙小于和/或等于5.0 cM的比例平均为98.1%。每条染色体上的标记数量从123个（第9号染色体）到315个（第4号染色体）不等，平均值为224.6个，相邻标记之间的距离从0.6 cM（第10号染色体）到1.3 cM（第9号染色体）不等，平均距离仅为0.98 cM。
本研究构建了一张高密度高粱遗传图谱。其总长度为2158.1 cM，覆盖所有10条染色体，共有2246个SLAF标记。该图谱的构建可为准确的基因定位、克隆以及分子标记辅助育种的应用提供详细信息。
