Guizhou Institute of Upland Crops, Guizhou Academy of Agricultural Sciences, Guiyang, 550006, China.
College of Agriculture, Guizhou University, Guiyang, 550025, China.
Theor Appl Genet. 2023 Mar 23;136(4):77. doi: 10.1007/s00122-023-04307-z.
Seventy-three QTL related to grain color and tannin content were identified in Chinese sorghum accessions, and a new recessive allelic variant of TAN2 gene was discovered. Sorghum is mainly used for brewing distilled liquors in China. Since grain tannins play an important role in liquor brewing, accurately understanding the relationship between grain color and tannin content can provide basis for selection standards of tannin sorghum. We resequenced a panel of 242 Chinese sorghum accessions and performed population structure and genome-wide association study (GWAS) to identify quantitative trait locus (QTL) affecting pericarp color, testa pigment, and tannin content. Phylogenetic analysis, principal component analysis (PCA), and admixture model were used to infer population structure. Two distinct genetic sub-populations were identified according to their corresponding northern and southern geographic origin. To investigate the genetic basis of natural variation in sorghum grain color, GWAS with 2,760,264 SNPs was conducted in four environments using multiple models (Blink, FarmCPU, GLM, and MLM). Seventy-three QTL were identified to be associated for the color of exocarp, mesocarp, testa, and tannin content on all chromosomes except chromosome 5, of which 47 might be novel QTL. Some important QTL were found to colocalize with orthologous genes in the flavonoid biosynthetic pathway from other plants, including orthologous of Arabidopsis (Arabidopsis thaliana) TT2, TT7, TT12, TT16 and AT5G41220 (GST), as well as orthologous of rice (Oryza sativa) MYB61 and OsbHLH025. Our investigation of the variation in grain color and tannin content in Chinese sorghum germplasm may help guide future sorghum breeding for liquor brewing.
在中国高粱品种中鉴定到与粒色和单宁含量相关的 73 个 QTL，并发现了 TAN2 基因的一个新的隐性等位变异。高粱在中国主要用于酿造蒸馏酒。由于籽粒单宁在酿酒中起着重要作用，准确了解粒色与单宁含量的关系可为单宁高粱的选择标准提供依据。我们对 242 份中国高粱品种进行了重测序，并进行了群体结构和全基因组关联研究（GWAS），以鉴定影响果皮颜色、种皮色素和单宁含量的数量性状位点（QTL）。系统发育分析、主成分分析（PCA）和混合模型用于推断群体结构。根据其对应的南北地理起源，确定了两个不同的遗传亚群。为了研究高粱粒色自然变异的遗传基础，我们在四个环境中使用多种模型（Blink、FarmCPU、GLM 和 MLM）对 2760264 个 SNPs 进行了 GWAS。在所有染色体上鉴定到 73 个与外果皮、中果皮、种皮和单宁含量颜色相关的 QTL，除了 5 号染色体外，其中 47 个可能是新的 QTL。在类黄酮生物合成途径的同源基因中发现了一些重要的 QTL，包括拟南芥（Arabidopsis thaliana）TT2、TT7、TT12、TT16 和 AT5G41220（GST）以及水稻（Oryza sativa）MYB61 和 OsbHLH025 的同源基因。我们对中国高粱种质中粒色和单宁含量的变异进行了研究，这可能有助于指导未来用于酿造蒸馏酒的高粱育种。
