Dissecting tocopherols content in maize (Zea mays L.), using two segregating populations and high-density single nucleotide polymorphism markers

BMC Plant Biology

Research Article

Trushar Shah¹  Yan Jianbing²  Farhan Ali³  Wang Weidong⁴  Zhang Dalong⁴  Cai Ye⁴  Li Qing⁴  Xu Shutu⁴  Li Zhigang⁴  Li Jiansheng⁴  Zhou Yi⁴  Yang Xiaohong⁴ 

[1] Department of Bioinformatics, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, India;National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, 430070, Wuhan, Hubei, China;National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, 430070, Wuhan, Hubei, China;Cereal Crops Research Institute, Nowshera, Khyber Pukhtoonkhwa, Pakistan;National Maize Improvement Center of China, China Agricultural University, 100193, Beijing, China;

关键词: Maize;    Tocopherols;    QTL mapping;   

DOI  :  10.1186/1471-2229-12-201

 received in 2012-02-13, accepted in 2012-10-30,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundTocopherols, which are vitamin E compounds, play an important role in maintaining human health. Compared with other staple foods, maize grains contain high level of tocopherols.ResultsTwo F2 populations (K22/CI7 and K22/Dan340, referred to as POP-1 and POP-2, respectively), which share a common parent (K22), were developed and genotyped using a GoldenGate assay containing 1,536 single nucleotide polymorphism (SNP) markers. An integrated genetic linkage map was constructed using 619 SNP markers, spanning a total of 1649.03 cM of the maize genome with an average interval of 2.67 cM. Seventeen quantitative trait loci (QTLs) for all the traits were detected in the first map and 13 in the second. In these two maps, QTLs for different traits were localized to the same genomic regions and some were co-located with candidate genes in the tocopherol biosynthesis pathway. Single QTL was responsible for 3.03% to 52.75% of the phenotypic variation and the QTLs in sum explained23.4% to 66.52% of the total phenotypic variation. A major QTL (qc5-1/qd5-1) affecting α-tocopherol (αT) was identified on chromosome 5 between the PZA03161.1 and PZA02068.1 in the POP-2. The QTL region was narrowed down from 18.7 Mb to 5.4 Mb by estimating the recombination using high-density markers of the QTL region. This allowed the identification of the candidate gene VTE4 which encodes γ-tocopherol methyltransferase, an enzyme that transforms γ-tocopherol (γT)to αT.ConclusionsThese results demonstrate that a few QTLs with major effects and several QTLs with medium to minor effects might contribute to the natural variation of tocopherols in maize grain. The high-density markers will help to fine map and identify the QTLs with major effects even in the preliminary segregating populations. Furthermore, this study provides a simple guide line for the breeders to improve traits that minimize the risk of malnutrition, especially in developing countries.

【 授权许可】

Unknown   
© Shutu et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.