title: Yield QTLome distribution correlates with gene density in maize.
abstract: The genetic control of yield and related traits in maize has been addressed by many quantitative trait locus (QTL) studies, which have produced a wealth of QTL information, also known as QTLome. In this study, we assembled a yield QTLome database and carried out QTL meta-analysis based on 44 published studies, representing 32 independent mapping populations and 49 parental lines. A total of 808 unique QTLs were condensed to 84 meta-QTLs and were projected on the 10 maize chromosomes. Seventy-four percent of QTLs showed a proportion of phenotypic variance explained (PVE) smaller than 10% confirming the high genetic complexity of grain yield. Yield QTLome projection on the genetic map suggested pericentromeric enrichment of QTLs. Conversely, pericentromeric depletion of QTLs was observed when the physical map was considered, suggesting gene density as the main driver of yield QTL distribution on chromosomes. Dominant and overdominant yield QTLs did not distribute differently from additive effect QTLs.
authors.affiliation: Department of Agricultural Sciences, University of Bologna, Viale Fanin 44, 40127 Bologna, Italy.
authors.forename: Ana Karine
authors.initials: AK
authors.lastname: Martinez
authors.affiliation: Department of Agricultural Sciences, University of Bologna, Viale Fanin 44, 40127 Bologna, Italy; Field Crops Programme, IRTA (Institute for Food and Agricultural Research and Technology), 25198 Lleida, Spain.
authors.forename: Jose Miguel
authors.initials: JM
authors.lastname: Soriano
authors.affiliation: Department of Agricultural Sciences, University of Bologna, Viale Fanin 44, 40127 Bologna, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Tuberosa
authors.affiliation: Semillas Fitó, Selva de Mar 111, 08019 Barcelona, Spain.
authors.forename: Rachil
authors.initials: R
authors.lastname: Koumproglou
authors.affiliation: Semillas Fitó, Selva de Mar 111, 08019 Barcelona, Spain.
authors.forename: Torben
authors.initials: T
authors.lastname: Jahrmann
authors.affiliation: Department of Agricultural Sciences, University of Bologna, Viale Fanin 44, 40127 Bologna, Italy. Electronic address: silvio.salvi@unibo.it.
authors.forename: Silvio
authors.initials: S
authors.lastname: Salvi
mesh_terms: D002874:Chromosome Mapping / Q000379:methods; D032461:Chromosomes, Plant / Q000235:genetics*; D030541:Databases, Genetic; D017343:Genes, Plant / Q000235:genetics*; D018745:Genome, Plant / Q000235:genetics; D000069600:Plant Breeding / Q000379:methods; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci / Q000235:genetics*; D003313:Zea mays / Q000235:genetics* / Q000254:growth & development
keywords: Heterosis; Meta-analysis; QTL; QTLome; Yield; Zea mays