title: Detecting QTLs and putative candidate genes involved in budbreak and flowering time in an apple multiparental population.
abstract: In temperate trees, growth resumption in spring time results from chilling and heat requirements, and is an adaptive trait under global warming. Here, the genetic determinism of budbreak and flowering time was deciphered using five related full-sib apple families. Both traits were observed over 3 years and two sites and expressed in calendar and degree-days. Best linear unbiased predictors of genotypic effect or interaction with climatic year were extracted from mixed linear models and used for quantitative trait locus (QTL) mapping, performed with an integrated genetic map containing 6849 single nucleotide polymorphisms (SNPs), grouped into haplotypes, and with a Bayesian pedigree-based analysis. Four major regions, on linkage group (LG) 7, LG10, LG12, and LG9, the latter being the most stable across families, sites, and years, explained 5.6-21.3% of trait variance. Co-localizations for traits in calendar days or growing degree hours (GDH) suggested common genetic determinism for chilling and heating requirements. Homologs of two major flowering genes, AGL24 and FT, were predicted close to LG9 and LG12 QTLs, respectively, whereas Dormancy Associated MADs-box (DAM) genes were near additional QTLs on LG8 and LG15. This suggests that chilling perception mechanisms could be common among perennial and annual plants. Progenitors with favorable alleles depending on trait and LG were identified and could benefit new breeding strategies for apple adaptation to temperature increase.
authors.affiliation: Institut National de la Recherche Agronomique (INRA), UMR 1334, AGAP CIRAD-INRA-Montpellier SupAgro, F-34398 Montpellier, France Montpellier SupAgro, UMR 1334, AGAP CIRAD-INRA-Montpellier SupAgro, F-34398 Montpellier, France.
authors.forename: Alix
authors.initials: A
authors.lastname: Allard
authors.affiliation: Biometris, Wageningen University and Research centre, Droevendaalsesteeg 1, PO Box 16, 6700AA, Wageningen, The Netherlands.
authors.forename: Marco C A M
authors.initials: MC
authors.lastname: Bink
authors.affiliation: Institut National de la Recherche Agronomique (INRA), UMR 1334, AGAP CIRAD-INRA-Montpellier SupAgro, F-34398 Montpellier, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Martinez
authors.affiliation: Montpellier SupAgro, UMR 1334, AGAP CIRAD-INRA-Montpellier SupAgro, F-34398 Montpellier, France.
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Kelner
authors.affiliation: Institut National de la Recherche Agronomique (INRA), UMR 1334, AGAP CIRAD-INRA-Montpellier SupAgro, F-34398 Montpellier, France.
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Legave
authors.affiliation: Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige, Trento, Italy Wageningen UR Plant Breeding, Wageningen University and Research Centre, Droevendaalsesteeg 1, PO Box 16, 6700AA, Wageningen, The Netherlands.
authors.forename: Mario
authors.initials: M
authors.lastname: di Guardo
authors.affiliation: Department of Biosciences, University of Milan, Via Celoria 26, 20133 Milan, Italy.
authors.forename: Erica A
authors.initials: EA
authors.lastname: Di Pierro
authors.affiliation: INRA, UMR1345, Institut de Recherche en Horticulture et Semences IRHS, INRA, Agrocampus-Ouest, Université d'Angers, SFR 4207 QUASAV, F-49071 Beaucouzé, France.
authors.forename: François
authors.initials: F
authors.lastname: Laurens
authors.affiliation: Wageningen UR Plant Breeding, Wageningen University and Research Centre, Droevendaalsesteeg 1, PO Box 16, 6700AA, Wageningen, The Netherlands.
authors.forename: Eric W
authors.initials: EW
authors.lastname: van de Weg
authors.affiliation: Institut National de la Recherche Agronomique (INRA), UMR 1334, AGAP CIRAD-INRA-Montpellier SupAgro, F-34398 Montpellier, France costes@supagro.inra.fr.
authors.forename: Evelyne
authors.initials: E
authors.lastname: Costes
mesh_terms: D035264:Flowers / Q000235:genetics / Q000254:growth & development*; D017343:Genes, Plant / Q000235:genetics* / Q000502:physiology; D006239:Haplotypes / Q000235:genetics; D027845:Malus / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D010375:Pedigree; D000069600:Plant Breeding; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D040641:Quantitative Trait Loci
keywords: Climate change; DAM genes; Malus×domestica (Borkh); QTL.; dormancy; flowering genes; pedigree-based analysis; phenology