title: Genetic determinism of anatomical and hydraulic traits within an apple progeny.
abstract: The apple tree is known to have an isohydric behaviour, maintaining rather constant leaf water potential in soil with low water status and/or under high evaporative demand. However, little is known on the xylem water transport from roots to leaves from the two perspectives of efficiency and safety, and on its genetic variability. We analysed 16 traits related to hydraulic efficiency and safety, and anatomical traits in apple stems, and the relationships between them. Most variables were found heritable, and we investigated the determinism underlying their genetic control through a quantitative trait loci (QTL) analysis on 90 genotypes from the same progeny. Principal component analysis (PCA) revealed that all traits related to efficiency, whether hydraulic conductivity, vessel number and area or wood area, were included in the first PC, whereas the second PC included the safety variables, thus confirming the absence of trade-off between these two sets of traits. Our results demonstrated that clustered variables were characterized by common genomic regions. Together with previous results on the same progeny, our study substantiated that hydraulic efficiency traits co-localized with traits identified for tree growth and fruit production.
authors.affiliation: INRA, UMR 1334 AGAP, F-34398 Montpellier Cedex 5, France. lauri@supagro.inra.fr
authors.forename: Pierre-Éric
authors.initials: PÉ
authors.lastname: Lauri
authors.forename: Olivier
authors.initials: O
authors.lastname: Gorza
authors.forename: Hervé
authors.initials: H
authors.lastname: Cochard
authors.forename: Sébastien
authors.initials: S
authors.lastname: Martinez
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Celton
authors.forename: Véronique
authors.initials: V
authors.lastname: Ripetti
authors.forename: Marc
authors.initials: M
authors.lastname: Lartaud
authors.forename: Xavier
authors.initials: X
authors.lastname: Bry
authors.forename: Catherine
authors.initials: C
authors.lastname: Trottier
authors.forename: Evelyne
authors.initials: E
authors.lastname: Costes
mesh_terms: D001692:Biological Transport; D055592:Biophysical Phenomena; D018745:Genome, Plant; D005838:Genotype; D027845:Malus / Q000033:anatomy & histology / Q000235:genetics*; D018547:Plant Stems / Q000033:anatomy & histology / Q000235:genetics; D025341:Principal Component Analysis; D040641:Quantitative Trait Loci; D019655:Quantitative Trait, Heritable; D014197:Trees / Q000033:anatomy & histology / Q000235:genetics; D014867:Water; D052584:Xylem
chemical_list: D014867:Water