A test for pre-adapted phenotypic plasticity in the invasive tree Acer negundo L Lamarque L.J. , Laurent (INRA , Cestas (France). UMR 1202 Biodiversité, Gènes et Communautés); Porte , Annabel (INRA , Cestas (France). UMR 1202 Biodiversité, Gènes et Communautés); Eymeric , Camille (INRA , Cestas (France). UMR 1202 Biodiversité, Gènes et Communautés) ...
2013
Publication
Phenotypic plasticity is a key mechanism associated with the spread of exotic plants and previous studies have found that invasive species are generally more plastic than co-occurring species. ...Comparatively, the evolution of phenotypic plasticity in plant invasion has received less attention, and in particular, the genetic basis of plasticity is largely unexamined. Native from North America, Acer negundo L. is aggressively impacting the riparian forests of southern and eastern Europe thanks to higher plasticity relative to co-occurring native species. We therefore tested here whether invasive populations have evolved increased plasticity since introduction. The performance of 1152 seedlings from 8 native and 8 invasive populations was compared in response to nutrient availability. Irrespective of nutrients, invasive populations had higher growth and greater allocation to above-ground biomass relative to their native conspecifics. More importantly, invasive genotypes did not show increased plasticity in any of the 20 traits examined. This result suggests that the high magnitude of plasticity to nutrient variation of invasive seedlings might be pre-adapted in the native range. Invasiveness of A. negundo could be explained by higher mean values of traits due to genetic differentiation rather than by evolution of increased plasticity.
Biodiversité urbaine: un campus vert dans la cité Consortium de chercheurs, d'animateurs scientifiques et de gestionnaires; Institut National de Recherche Agronomique UMR 1202 Biodiversité, Gènes et Communautés; Porte, Annabel ...
Biodiversité urbaine: un campus vert dans la cité(2013),
2013
Publication
Biodiversité urbaine: un campus vert dans la cité Consortium de chercheurs, d'animateurs scientifiques et de gestionnaires; Institut National de Recherche Agronomique UMR 1202 Biodiversité, Gènes et Communautés; Porte, Annabel ...
Biodiversité urbaine: un campus vert dans la cité(2013),
2013
Publication
Les dépérissements forestiers récents, observés aux quatre coins du monde, ainsi que les pertes sévères de rendement agricole, dues à des sécheresses intenses, ont amené les scientifiques à ...rechercher les mécanismes physiologiques sous-jacents afin de mieux prédire ces évènements et repérer des espèces plus adaptées. Dans leurs laboratoires, ils ont identifié un dysfonctionnement physiologique majeur lors d’un stress hydrique intense : la cavitation, évènement qui conduit à l’embolie des vaisseaux conducteurs de sève ascendante.
Biodiversité urbaine: un campus vert dans la cité Porte , Annabel (INRA , Cestas (France). UMR 1202 Biodiversité, Gènes et Communautés); Delzon , Sylvain (INRA , Cestas (France). UMR 1202 Biodiversité, Gènes et Communautés); Guengant , Yann (INRA , Cestas (France). UMR 1202 Biodiversité, Gènes et Communautés) ...
2013
Publication
Micro-evolutionary patterns of juvenile wood density in a pine species Lamy , Jean-Baptiste (INRA , Cestas (France). UMR 1202 Biodiversité, Gènes et Communautés); Lagane , Frédéric (INRA , Cestas (France). UMR 1202 Biodiversité, Gènes et Communautés); Plomion , Christophe (INRA , Cestas (France). UMR 1202 Biodiversité, Gènes et Communautés) ...
2012
Publication
Wood density can be considered an adaptive trait, because it ensures the safe and efficient transport of water from the roots to the leaves, mechanical support for the body of the plant and the ...storage of biological chemicals. Its variability has been extensively described in narrow genetic backgrounds and in wide ranges of forest tree species, but little is known about the extent of natural genetic and phenotypic variability within species. This information is essential to our understanding of the evolutionary forces that have shaped this trait, and for the evaluation of its inclusion in breeding programs. We assessed juvenile wood density, leaf area, total aboveground biomass, and growth in six Pinus pinaster populations of different geographic origins (France, Spain, and Morocco) growing in a provenance-progeny trial. No genetic differentiation was found for wood density, whereas all other traits significantly differed between populations. Heritability of this trait was moderate, with a low additive genetic variance. For retrospective identification of the evolutionary forces acting on juvenile wood density, we compared the distribution of neutral markers (F ST) and quantitative genetic differentiation (Q ST). We found that Q ST was significantly lower than F ST, suggesting evolutionary stasis. Furthermore, we did not detect any relationship between juvenile wood density and drought tolerance (resistance to cavitation), suggesting that this trait could not be used as a proxy for drought tolerance at the intraspecific level.
Quelques curiosités Delzon, Sylvain S.; Lassègues, Anne
Jardins de France,
2013
623
Magazine Article
Wollemia nobilis, presque aussi rare qu’un dinosaure… Son histoire est très récente car cette espèce n’a été découverte qu’en 1994. En effet, quelle ne fut pas la surprise du garde chasse australien, ...David Noble, de découvrir dans un canyon des montagnes du Parc National Wollemi au nord de Sydney cet arbre inconnu jusqu’alors. Depuis, on considère que ce conifère est l'une des plus grandes découvertes botaniques du XXe siècle.
