Open AccessBeyond pathways: genetic dissection of tocopherol content in maize kernels by combining linkage and association analyses
Author(s) -
Wang Hong,
Xu Shutu,
Fan Yaming,
Liu Nannan,
Zhan Wei,
Liu Haijun,
Xiao Yingjie,
Li Kun,
Pan Qingchun,
Li Wenqiang,
Deng Min,
Liu Jie,
Jin Min,
Yang Xiaohong,
Li Jiansheng,
Li Qing,
Yan Jianbing
Publication year - 2018
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.12889
Subject(s) - quantitative trait locus , biology , association mapping , genetics , candidate gene , genome wide association study , family based qtl mapping , genetic linkage , genetic architecture , genetic association , gene , allele , gene mapping , single nucleotide polymorphism , genotype , chromosome
Summary Although tocopherols play an important role in plants and animals, the genetic architecture of tocopherol content in maize kernels has remained largely unknown. In this study, linkage and association analyses were conducted to examine the genetic architecture of tocopherol content in maize kernels. Forty‐one unique quantitative trait loci ( QTL s) were identified by linkage mapping in six populations of recombinant inbred lines ( RIL s). In addition, 32 significant loci were detected via genome‐wide association study ( GWAS ), 18 of which colocalized with the QTL s identified by linkage mapping. Fine mapping of a major QTL validated the accuracy of GWAS and QTL mapping results and suggested a role for nontocopherol pathway genes in the modulation of natural tocopherol variation. We provided genome‐wide evidence that genes involved in fatty acid metabolism, chlorophyll metabolism and chloroplast function may affect natural variation in tocopherols. These findings were confirmed through mutant analysis of a particular gene from the fatty acid pathway. In addition, the favourable alleles for many of the significant SNP s/ QTL s represented rare alleles in natural populations. Together, our results revealed many novel genes that are potentially involved in the variation of tocopherol content in maize kernels. Pyramiding of the favourable alleles of the newly elucidated genes and the well‐known tocopherol pathway genes would greatly improve tocopherol content in maize.