title: Comprehensive genetic dissection of wood properties in a widely-grown tropical tree: Eucalyptus.
abstract: BACKGROUND
  Eucalyptus is an important genus in industrial plantations throughout the world and is grown for use as timber, pulp, paper and charcoal. Several breeding programmes have been launched worldwide to concomitantly improve growth performance and wood properties (WPs). In this study, an interspecific cross between Eucalyptus urophylla and E. grandis was used to identify major genomic regions (Quantitative Trait Loci, QTL) controlling the variability of WPs.
  
  
  RESULTS
  Linkage maps were generated for both parent species. A total of 117 QTLs were detected for a series of wood and end-use related traits, including chemical, technological, physical, mechanical and anatomical properties. The QTLs were mainly clustered into five linkage groups. In terms of distribution of QTL effects, our result agrees with the typical L-shape reported in most QTL studies, i.e. most WP QTLs had limited effects and only a few (13) had major effects (phenotypic variance explained > 15%). The co-locations of QTLs for different WPs as well as QTLs and candidate genes are discussed in terms of phenotypic correlations between traits, and of the function of the candidate genes. The major wood property QTL harbours a gene encoding a Cinnamoyl CoA reductase (CCR), a structural enzyme of the monolignol-specific biosynthesis pathway.
  
  
  CONCLUSIONS
  Given the number of traits analysed, this study provides a comprehensive understanding of the genetic architecture of wood properties in this Eucalyptus full-sib pedigree. At the dawn of Eucalyptus genome sequence, it will provide a framework to identify the nature of genes underlying these important quantitative traits.
authors.affiliation: CIRAD, Department of Biological System, Research Unit "Genetic improvement and adaptation of mediterranean and tropical plants" TA A-108/C, Campus International de Baillarguet, 34398 Montpellier Cedex, France. gion@cirad.fr
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Gion
authors.forename: Audrey
authors.initials: A
authors.lastname: Carouché
authors.forename: Sylvie
authors.initials: S
authors.lastname: Deweer
authors.forename: Franck
authors.initials: F
authors.lastname: Bedon
authors.forename: Frédérique
authors.initials: F
authors.lastname: Pichavant
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Charpentier
authors.forename: Henri
authors.initials: H
authors.lastname: Baillères
authors.forename: Philippe
authors.initials: P
authors.lastname: Rozenberg
authors.forename: Victor
authors.initials: V
authors.lastname: Carocha
authors.forename: Nina
authors.initials: N
authors.lastname: Ognouabi
authors.forename: Daniel
authors.initials: D
authors.lastname: Verhaegen
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Grima-Pettenati
authors.forename: Philippe
authors.initials: P
authors.lastname: Vigneron
authors.forename: Christophe
authors.initials: C
authors.lastname: Plomion
mesh_terms: D002874:Chromosome Mapping / Q000379:methods*; D005052:Eucalyptus / Q000033:anatomy & histology / Q000737:chemistry / Q000235:genetics* / Q000254:growth & development; D017343:Genes, Plant / Q000235:genetics*; D006824:Hybridization, Genetic; D040641:Quantitative Trait Loci / Q000235:genetics; D014934:Wood / Q000033:anatomy & histology / Q000737:chemistry / Q000235:genetics* / Q000254:growth & development