title: Fostered and left behind alleles in peanut: interspecific QTL mapping reveals footprints of domestication and useful natural variation for breeding.
abstract: BACKGROUND
  Polyploidy can result in genetic bottlenecks, especially for species of monophyletic origin. Cultivated peanut is an allotetraploid harbouring limited genetic diversity, likely resulting from the combined effects of its single origin and domestication. Peanut wild relatives represent an important source of novel alleles that could be used to broaden the genetic basis of the cultigen. Using an advanced backcross population developed with a synthetic amphidiploid as donor of wild alleles, under two water regimes, we conducted a detailed QTL study for several traits involved in peanut productivity and adaptation as well as domestication.
  
  
  RESULTS
  A total of 95 QTLs were mapped in the two water treatments. About half of the QTL positive effects were associated with alleles of the wild parent and several QTLs involved in yield components were specific to the water-limited treatment. QTLs detected for the same trait mapped to non-homeologous genomic regions, suggesting differential control in subgenomes as a consequence of polyploidization. The noteworthy clustering of QTLs for traits involved in seed and pod size and in plant and pod morphology suggests, as in many crops, that a small number of loci have contributed to peanut domestication.
  
  
  CONCLUSIONS
  In our study, we have identified QTLs that differentiated cultivated peanut from its wild relatives as well as wild alleles that contributed positive variation to several traits involved in peanut productivity and adaptation. These findings offer novel opportunities for peanut improvement using wild relatives.
authors.affiliation: Cirad, UMR AGAP, TA A108/3, Avenue Agropolis, Montpellier, France.
authors.forename: Daniel
authors.initials: D
authors.lastname: Fonceka
authors.forename: Hodo-Abalo
authors.initials: HA
authors.lastname: Tossim
authors.forename: Ronan
authors.initials: R
authors.lastname: Rivallan
authors.forename: Hélène
authors.initials: H
authors.lastname: Vignes
authors.forename: Issa
authors.initials: I
authors.lastname: Faye
authors.forename: Ousmane
authors.initials: O
authors.lastname: Ndoye
authors.forename: Márcio C
authors.initials: MC
authors.lastname: Moretzsohn
authors.forename: David J
authors.initials: DJ
authors.lastname: Bertioli
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Glaszmann
authors.forename: Brigitte
authors.initials: B
authors.lastname: Courtois
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Rami
mesh_terms: D000483:Alleles; D010367:Arachis / Q000235:genetics*; D002874:Chromosome Mapping / Q000379:methods*; D003433:Crosses, Genetic; D011123:Polyploidy; D040641:Quantitative Trait Loci / Q000235:genetics*