title: Genetic basis of maize kernel starch content revealed by high-density single nucleotide polymorphism markers in a recombinant inbred line population.
abstract: BACKGROUND
  Starch from maize kernels has diverse applications in human and animal diets and in industry and manufacturing. To meet the demands of these applications, starch quantity and quality need improvement, which requires a clear understanding of the functional mechanisms involved in starch biosynthesis and accumulation. In this study, a recombinant inbred line (RIL) population was developed from a cross between inbred lines CI7 and K22. The RIL population, along with both parents, was grown in three environments, and then genotyped using the MaizeSNP50 BeadChip and phenotyped to dissect the genetic architecture of starch content in maize kernels.
  
  
  RESULTS
  Based on the genetic linkage map constructed using 2,386 bins as markers, six quantitative trait loci (QTLs) for starch content in maize kernels were detected in the CI7/K22 RIL population. Each QTL accounted for 4.7% (qSTA9-1) to 10.6% (qSTA4-1) of the starch variation. The QTL interval was further reduced using the bin-map method, with the physical distance of a single bin at the QTL peak ranging from 81.7 kb to 2.2 Mb. Based on the functional annotations and prior knowledge of the genes in the top bin, seven genes were considered as potential candidate genes for the identified QTLs. Three of the genes encode enzymes in non-starch metabolism but may indirectly affect starch biosynthesis, and four genes may act as regulators of starch biosynthesis.
  
  
  CONCLUSIONS
  A few large-effect QTLs, together with a certain number of minor-effect QTLs, mainly contribute to the genetic architecture of kernel starch content in our maize biparental linkage population. All of the identified QTLs, especially the large-effect QTL, qSTA4-1, with a small QTL interval, will be useful for improving the maize kernel starch content through molecular breeding.
authors.affiliation: National Maize Improvement Center of China, Beijing Key Laboratory of Crop Genomics and Genetic Improvement, China Agricultural University, 100193, Beijing, China. wangtt0615@cau.edu.cn.
authors.forename: Tingting
authors.initials: T
authors.lastname: Wang
authors.affiliation: National Maize Improvement Center of China, Beijing Key Laboratory of Crop Genomics and Genetic Improvement, China Agricultural University, 100193, Beijing, China. kumine@163.com.|College of Agronomy, Northwest A&F University, Yangling, Shaanxi, 712100, China. kumine@163.com.
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.affiliation: National Maize Improvement Center of China, Beijing Key Laboratory of Crop Genomics and Genetic Improvement, China Agricultural University, 100193, Beijing, China. hushutingcau@163.com.
authors.forename: Shuting
authors.initials: S
authors.lastname: Hu
authors.affiliation: National Maize Improvement Center of China, Beijing Key Laboratory of Crop Genomics and Genetic Improvement, China Agricultural University, 100193, Beijing, China. xyn_xyn@126.com.
authors.forename: Yingni
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: National Key Laboratory of Crop Improvement, Huazhong Agricultural University, Wuhan, 430070, Hubei, China. tonghao0605@gmail.com.
authors.forename: Hao
authors.initials: H
authors.lastname: Tong
authors.affiliation: National Key Laboratory of Crop Improvement, Huazhong Agricultural University, Wuhan, 430070, Hubei, China. panqingchunmice@163.com.
authors.forename: Qingchun
authors.initials: Q
authors.lastname: Pan
authors.affiliation: College of Agronomy, Northwest A&F University, Yangling, Shaanxi, 712100, China. xjq2934@163.com.
authors.forename: Jiquan
authors.initials: J
authors.lastname: Xue
authors.affiliation: National Key Laboratory of Crop Improvement, Huazhong Agricultural University, Wuhan, 430070, Hubei, China. yjianbing@mail.hzau.edu.cn.
authors.forename: Jianbing
authors.initials: J
authors.lastname: Yan
authors.affiliation: National Maize Improvement Center of China, Beijing Key Laboratory of Crop Genomics and Genetic Improvement, China Agricultural University, 100193, Beijing, China. lijiansheng@cau.edu.cn.
authors.forename: Jiansheng
authors.initials: J
authors.lastname: Li
authors.affiliation: National Maize Improvement Center of China, Beijing Key Laboratory of Crop Genomics and Genetic Improvement, China Agricultural University, 100193, Beijing, China. yxiaohong@cau.edu.cn.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Yang
mesh_terms: D002874:Chromosome Mapping; D032461:Chromosomes, Plant / Q000235:genetics; D008040:Genetic Linkage; D007178:Inbreeding; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci; D012639:Seeds / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013213:Starch / Q000032:analysis / Q000378:metabolism*; D003313:Zea mays / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D013213:Starch