Environment-dependent microevolution in a Mediterranean pine (Pinus pinaster Aiton).

Détails

Ressource 1Télécharger: BIB_22F075A6F503.P001.pdf (431.53 [Ko])
Etat: Serval
Version: de l'auteur
ID Serval
serval:BIB_22F075A6F503
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Environment-dependent microevolution in a Mediterranean pine (Pinus pinaster Aiton).
Périodique
BMC Evolutionary Biology
Auteur(s)
Alía R., Chambel R., Notivol E., Climent J., González-Martínez S.C.
ISSN
1471-2148 (Electronic)
ISSN-L
1471-2148
Statut éditorial
Publié
Date de publication
2014
Peer-reviewed
Oui
Volume
14
Pages
200
Langue
anglais
Résumé
BACKGROUND: A central question for understanding the evolutionary responses of plant species to rapidly changing environments is the assessment of their potential for short-term (in one or a few generations) genetic change. In our study, we consider the case of Pinus pinaster Aiton (maritime pine), a widespread Mediterranean tree, and (i) test, under different experimental conditions (growth chamber and semi-natural), whether higher recruitment in the wild from the most successful mothers is due to better performance of their offspring; and (ii) evaluate genetic change in quantitative traits across generations at two different life stages (mature trees and seedlings) that are known to be under strong selection pressure in forest trees.
RESULTS: Genetic control was high for most traits (h2 = 0.137-0.876) under the milder conditions of the growth chamber, but only for ontogenetic change (0.276), total height (0.415) and survival (0.719) under the more stressful semi-natural conditions. Significant phenotypic selection gradients were found in mature trees for traits related to seed quality (germination rate and number of empty seeds). Moreover, female relative reproductive success was significantly correlated with offspring performance for specific leaf area (SLA) in the growth chamber experiment, and stem mass fraction (SMF) in the experiment under semi-natural conditions, two adaptive traits related to abiotic stress-response in pines. Selection gradients based on genetic covariance of seedling traits and responses to selection at this stage involved traits related to biomass allocation (SMF) and growth (as decomposed by a Gompertz model) or delayed ontogenetic change, depending also on the testing environment.
CONCLUSIONS: Despite the evidence of microevolutionary change in adaptive traits in maritime pine, directional or disruptive changes are difficult to predict due to variable selection at different life stages and environments. At mature-tree stages, higher female effective reproductive success can be explained by differences in their production of offspring (due to seed quality) and, to a lesser extent, by seemingly better adapted seedlings. Selection gradients and responses to selection for seedlings also differed across experimental conditions. The distinct processes involved at the two life stages (mature trees or seedlings) together with environment-specific responses advice caution when predicting likely evolutionary responses to environmental change in Mediterranean forest trees.
Mots-clé
Biological Evolution, Gene-Environment Interaction, Phenotype, Pinus/classification, Pinus/genetics, Reproduction, Seeds/physiology, Trees/genetics, Trees/physiology, Water/metabolism
Pubmed
Web of science
Création de la notice
16/02/2015 21:40
Dernière modification de la notice
03/03/2018 14:52
Données d'usage