title: Heterosis is prevalent for multiple traits in diverse maize germplasm.
abstract: BACKGROUND
  Heterosis describes the superior phenotypes observed in hybrids relative to their inbred parents. Maize is a model system for studying heterosis due to the high levels of yield heterosis and commercial use of hybrids.
  
  
  METHODS
  The inbred lines from an association mapping panel were crossed to a common inbred line, B73, to generate nearly 300 hybrid genotypes. Heterosis was evaluated for seventeen phenotypic traits in multiple environments. The majority of hybrids exhibit better-parent heterosis in most of the hybrids measured. Correlations between the levels of heterosis for different traits were generally weak, suggesting that the genetic basis of heterosis is trait-dependent.
  
  
  CONCLUSIONS
  The ability to predict heterosis levels using inbred phenotype or genetic distance between the parents varied for the different traits. For some traits it is possible to explain a significant proportion of the heterosis variation using linear modeling while other traits are more difficult to predict.
authors.affiliation: USDA-ARS, Plant Genetics Research Unit, and Division of Plant Sciences, University of Missouri, Columbia, Missouri, United States of America. sherry.flint-garcia@ars.usda.gov
authors.forename: Sherry A
authors.initials: SA
authors.lastname: Flint-Garcia
authors.forename: Edward S
authors.initials: ES
authors.lastname: Buckler
authors.forename: Peter
authors.initials: P
authors.lastname: Tiffin
authors.forename: Elhan
authors.initials: E
authors.lastname: Ersoz
authors.forename: Nathan M
authors.initials: NM
authors.lastname: Springer
mesh_terms: D003433:Crosses, Genetic; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D005838:Genotype; D006823:Hybrid Vigor / Q000235:genetics*; D006824:Hybridization, Genetic; D016014:Linear Models; D015233:Models, Statistical; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D003313:Zea mays / Q000235:genetics* / Q000502:physiology*