School of Agriculture Sciences, Zhengzhou University, Zhengzhou, 450000, Henan, China.
Institute of Cotton Research of Chinese Academy of Agricultural Science/State Key Laboratory of Cotton Biology, Anyang, 455000, Henan, China.
Planta. 2021 Apr 11;253(5):95. doi: 10.1007/s00425-021-03622-3.
The significant number loci and candidate genes of root color in Gossypium arboreum are identified and provide a theoretical basis of root color for cotton. A stimulating phenomenon was observed on the 4th day of sowing in the root color of some G. arboreum accessions that turned red. To disclose the genetic mechanisms of root color formation via genome and transcript levels, we identified the significant number of SNPs and candidate genes that are related to root color through genome-wide association study (GWAS) and RNAseq analysis in G. arboreum. Initially, 215 no. of G. arboreum accessions was collected, and the colors of root on the 4th, 6th and 9th day of germination were recorded. The GWAS demonstrated that 225 significant SNPs and 47 candidate genes have been identified totally. The strongest signal SNP A04_91824 could greatly distinguish the root color with most "C" allele accessions have displayed white and "T" allele accessions displayed red. RNAseq was performed on accessions having the white and red root, and results revealed that 12 and 138 DEGs were detected on 2nd and 4th day, respectively. ACD6, UFGT, and LYM2 were the most related genes of root color, later, verified by qRT-PCR. The mature zone of red and the white roots was observed by the histological section method, and results shown that cells were more closely arranged in the white root, and both average cell length and cell width were longer in the red root. This study will be helpful to cotton breeders for utilization of several elite genes and related SNPs related to root color, in addition to find linkage with economically important traits of interests.
鉴定了陆地棉根系颜色的大量数量位点和候选基因，为棉花根系颜色提供了理论基础。在播种后的第 4 天，一些陆地棉品系的根系变红，观察到一个令人兴奋的现象。为了从基因组和转录水平揭示根系颜色形成的遗传机制，我们通过全基因组关联研究（GWAS）和 RNAseq 分析鉴定了与根系颜色相关的大量 SNP 和候选基因。最初，收集了 215 份陆地棉品系，记录了第 4、6 和 9 天萌发时根系的颜色。GWAS 表明，共鉴定出 225 个显著 SNP 和 47 个候选基因。最强信号 SNP A04_91824 可显著区分根系颜色，大多数“C”等位基因品系显示白色，“T”等位基因品系显示红色。对具有白色和红色根系的品系进行 RNAseq 分析，结果表明，在第 2 天和第 4 天分别检测到 12 个和 138 个 DEGs。ACD6、UFGT 和 LYM2 是与根系颜色最相关的基因，随后通过 qRT-PCR 进行了验证。通过组织学切片方法观察红色和白色根系的成熟区，结果表明，白色根系的细胞排列更紧密，红色根系的平均细胞长度和细胞宽度更长。这项研究将有助于棉花育种家利用与根系颜色相关的几个优秀基因和相关 SNP，以及发现与经济上重要性状的连锁。
