Résumé
[ES] Las poblaciones de plantas reaccionan al cambio climático de muy diversas maneras, y para evaluarlas es crucial comprender cómo se comportan los individuos en las distintas condiciones. El rendimiento fenotípico podría tener una base genética o estar influenciado únicamente por el medio ambiente (Plasticidad). Conocer el potencial del acervo genético de los diferentes grupos genéticos repartidos por los gradientes climáticos es significativo para determinar la adaptación o la plasticidad. El manzano cultivado (Malus domestica Borkh.) tiene cruces de hibridación natural con el manzano cangrejo europeo Malus sylvestris y parientes silvestres Malus orientalis, y M. sylvestris todos conservados en el huerto de manzanas silvestres de Saclay instalado en noviembre de 2020 en Francia. Se plantaron poblaciones de dos especies de parientes silvestres del manzano (M. orientalis, M. sylvestris) y de manzana comercial domesticada (M. domestica) procedentes de 4 lugares (Rumanía, Francia, Armenia, Dinamarca), en la estación biológica francesa ECOTRON, celdas de simulación climática de la temperatura y la humedad. Se recogieron muestras de hojas para extraer ARN
El objetivo principal de este estudio era determinar las diferencias en la expresión génica y los rasgos ecofisiológicos entre las poblaciones de manzanas silvestres M. sylvestris, M. orientalis y la manzana comercial M. domestica debido a la variación climática en la estación biológica ECOTRON. Se comprobó la coexpresión diferencial de genes que influyen en la mayoría de los rasgos fenotípicos para detectar la adaptación entre poblaciones o la plasticidad fenotípica. Se midieron los rasgos ecofisiológicos superficie foliar, fotosíntesis, flavonoides, e índice de balance de nitrógeno (NBI), tasa de crecimiento (absoluta y relativa) y, absorción de carbono/nitrógeno, para determinar el rendimiento fenotípico. Se determinaron los patrones de adaptación local para la supervivencia de las poblaciones de manzanas silvestres francesas y danesas, mientras que la mala adaptación de la manzana silvestre rumana. La manzana cultivada y la manzana silvestre del Cáucaso presentaron altas tasas de supervivencia independientemente del clima, lo que sugiere una gran plasticidad. También demostramos que las manzanas silvestres presentan un alto nivel de plasticidad al clima en las primeras etapas de crecimiento, y que existían compensaciones entre la altura y el número de hojas. Todas las variaciones en el fenotipo entre ambientes y la expresión genética de las plantas de manzana serán una posible fuente de información que puede utilizarse en los programas de mejora de cultivos
Auteurs, date et publication :
Auteurs Luis Jorge Sandoval Aguirre
Date : 2022
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
Analysis of 65 grasslands worldwide from the Nutrient Network experiment reveals that plant communities with higher α- and β-diversity have higher levels of ecosystem multifunctionality, and that this effect is amplified across scales.
Auteurs, date et publication :
Auteurs Yann Hautier , Forest Isbell , Elizabeth T. Borer , Eric W. Seabloom , W. Stanley Harpole , Eric M. Lind , Andrew S. MacDougall , Carly J. Stevens , Peter B. Adler , Juan Alberti , Jonathan D. Bakker , Lars A. Brudvig , Yvonne M. Buckley , Marc Cadotte , Maria C. Caldeira , Enrique J. Chaneton , Chengjin Chu , Pedro Daleo , Christopher R. Dickman , John M. Dwyer
Publication : Nature Ecology & Evolution
Date : 2018
Volume : 2
Issue : 1
Pages : 50
Catégorie(s)
#CEREEP #CNRS #ENSRésumé
In fragmented landscapes, the reduced connectivity among patches drives the evolution of movement strategies through an increase of transience costs. Reduced movements may further alter heterogeneity in biotic and abiotic conditions experienced by individuals. The joint action of local conditions and matrix permeability may shape emigration decisions. Here, we tested the interactive effects of predation risk and matrix permeability on movement propensity, movement costs and movers’ phenotype in the common toad Bufo bufo. In a full-crossed experimental design, we assessed the movement propensity of juveniles in three connectivity treatments (from poorly to highly permeable matrix), with or without predation risk in their living patch. We also assessed the relationships between movement propensity and morphological traits (i.e. body and leg length) and how it affected the movement cost (i.e. mass loss). Movement propensity increased in presence of predation risk, while matrix permeability had no effect. However, matrix permeability interacted with predation risk to influence movers’ phenotype and the physiological cost they endured while moving. In particular, a wellknown movement syndrome in toads (i.e. movement propensity positively related to longer legs) depended on the interaction between matrix permeability and predation risk and resulted in differences in mass loss among matrix types. Movers lost more mass on average than residents except when they also displayed longer legs or when they crossed the most permeable matrix in the presence of predation risk. Our results show that matrix permeability shapes the physiological cost of dispersal by changing the identity of individuals moving away from local conditions. As the movers’ phenotype can importantly alter (meta)population dynamics, context-dependency of dispersal syndromes should be considered in studies predicting the functioning of human-altered natural systems.
Auteurs, date et publication :
Auteurs Laurane Winandy , Julien Cote , Lucie Di Gesu , Félix Pellerin , Audrey Trochet , Delphine Legrand
Publication : Oikos
Date : 2025
Volume : 128
Issue : 10
Pages : 1402-1412
Catégorie(s)
#CNRS #Metatron terrestreRésumé
Methods: We studied the functional relationships between plants and grasshoppers in sub-alpine grasslands under different management regimes in the Central French Alps. We applied the theoretical multitrophic response–effect framework described by (Journal of Vegetation Science, 24, this issue) to identify key traits linking plants and grasshoppers to biomass production. The linkages between selected plant and grasshopper traits were analysed using community-weighted mean traits (CWM) and functional diversity (FD; Rao’s quadratic diversity).
Results: Uni- and multivariate models provided evidence about the relative importance of trait linkages within and across trophic levels. We showed that management affected both plant and grasshopper traits and that the interaction between them was linked to biomass production. While a number of CWM traits and FD were involved in the interaction, CWM of leaf dry matter content (LDMC) and grasshopper dry body mass (GMass) chiefly mediated the impact of management change on biomass production.
Conclusions: Our study suggests that both trait values of the most abundant species and functional trait variation within and across trophic levels in combination may best explain the impact of land-use changes on ecosystem function. To improve our mechanistic understanding across trophic levels, a better knowledge of response and effect traits remains a major goal, especially for animal ecologists, while a strong collaboration among disciplines is needed to bridge the existing gaps.
Auteurs, date et publication :
Auteurs Marco Moretti , Francesco de Bello , Sébastien Ibanez , Simone Fontana , Gianni B. Pezzatti , Frank Dziock , Christian Rixen , Sandra Lavorel , Robin Pakeman
Publication : Journal of Vegetation Science
Date : 2025
Volume : 24
Issue : 5
Pages : 949-962
Catégorie(s)
#CNRS #Lautaret #UGAAuteurs, date et publication :
Auteurs Anne Hélène Fostier , José Javier Melendez-Perez , Larissa Richter
Publication : Environmental pollution
Date : 2025
Volume : 206
Pages : 605-610
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Leaf litter, at the interface between the soil and the atmosphere, releases Biogenic Volatile Organic Compounds (BVOC) which play an important role both in global atmospheric chemistry and plant ecology. Litter is especially important in the Mediterranean region, where it is produced in high amounts and decomposes slowly. Only leaf litter emissions of two dominant species (Pinus halepensis and Eucalyptus spp.) present in the Mediterranean region have been studied so far. The aim of this study is to characterize (quantitatively and qualitatively) the BVOC emissions (C10–C15) from litter (freshly fallen and non-decomposed leaves) under laboratory conditions. Sixteen species frequently found in the Mediterranean region were considered, nine of which possess terpene storage structures. Results show a large diversity of BVOC (87 compounds detected, terpenes, alkanes, alkenes, aldehydes, ketones, benzenoids), with terpene emission being higher than non-terpenic emission in most of the cases. Species were classified within 3 categories: negligible emitters (e.g. Acer monspessulanum and Quercus ilex, < 0.10 μg.gDM − 1.h− 1), low emitters (Pinus pinea, Quercus pubescens, 0.1–1.0 μg.gDM − 1.h− 1) and moderate emitters (Thymus vulgaris, Cotinus coggygria and Pinus halepensis between 1.5 and 4.7 μg.gDM − 1.h− 1). Litter that possessed terpene storage structures and known to store high terpene concentration did not always release the highest terpene emission rates (e.g. Eucalyptus globulus, Rosmarinus officinalis). Species that do not possess such structures release only non terpenic emissions (e.g. alkanes, aldehydes). Estimation of the potential contribution of P. halepensis and Q. pubescens litter to O3 and secondary organic aerosol (SOA) formation in the atmosphere showed that P. halepensis has a larger potential impact on the global air quality than Q. pubescens. This study will contribute to build future BVOC emissions inventories on leaf litter for their further integration in atmospheric chemistry models.
Auteurs, date et publication :
Auteurs Justine Viros , Fernandez C , Wortham H , Gavinet J , Lecareux C , Ormeño E
Publication : Atmospheric Environment
Date : 2025
Volume : 242
Pages : 117815
Catégorie(s)
#CNRS #FORET O3HPRésumé
The objective of the study was to evaluate changes in microbial communities with the predicted arrival of new species to Mediterranean forests under projected intensification of water stress conditions. For that, litter from three Mediterranean forests dominated respectively by Quercus pubescens Willd., Quercus ilex L. and Pinus halepensis Mill. were collected, and placed to their ‘home’ forest but also to the two other forests under natural and amplified drought conditions (i.e. rainfall reduction of 30%). Quantitative PCR showed that overall, actinobacteria and total bacteria were more abundant in Q. pubescens and Q. ilex than in P. halepensis litter. However, the abundance of both groups was dependent on the forest sites: placement of allochthonous litter to Q. pubescens and P. halepensis forests (i.e. P. halepensis and Q. pubescens, respectively) increased bacterial and fungal abundances, while no effect was observed in Q. ilex forest. P. halepensis litter in Q. pubescens and Q. ilex forests significantly reduced actinobacteria (A/F) and total bacteria (B/F) to fungi ratios. The reduction of rainfall did not influence actinobacteria and bacteria but caused an increase of fungi. As a result, a reduction of A/F ratio is expected with the plant community change towards the dominance of spreading P. halepensis under amplified drought conditions.
Auteurs, date et publication :
Auteurs S Pereira , A Burešová , J Kopecky , P Mádrová , A Aupic-Samain , C Fernandez , V Baldy , M Sagova-Mareckova
Publication : FEMS Microbiology Ecology
Date : 2019
Pages : fiz168
Catégorie(s)
#CNRS #FORET FontBlanche #FORET O3HP #FORET PuechabonRésumé
Important biochemical reactions in soils are catalyzed by extracellular enzymes, which are synthesized by microbes and plant roots. Although enzyme activities can significantly affect the decomposition of soil organic matter and thus influence the storage and cycling of carbon (C) and nitrogen (N), it is not clear how enzyme activities relate to changes in the C and N content of different grassland soils. Here we address whether the activity of C-acquiring (b-1,4-glucosidase, BG) and N-acquiring (L-leucine aminopeptidase (LAP) and b-1,4-N-acetyl-glucosaminidase (NAG)) enzymes is linked to changes in the C and N content of a variety of human-managed grassland soils. We selected soils which have a well-documented management history going back at least 19 years in relation to changes in land use (grazing, mowing, ploughing), nutrient fertilization and lime (CaCO3) applications. Overall we found a positive relationship between BG activity and soil C content as well as between LAP þ NAG activity and soil N. These positive relationships occurred across grasslands with very different soil pH and management history but not in intensively managed grasslands where increases in soil bulk density (i.e. high soil compaction) negatively affected enzyme activity. We also found evidence that chronic nutrient fertilization contributed to increases in soil C content and this was associated with a significant increase in BG activity when compared to unfertilized soils. Our study suggests that while the activities of C- and N-acquiring soil enzymes are positively related to soil C and N content, these activities respond significantly to changes in management (i.e. soil compaction and nutrient fertilization). In particular, the link between BG activity and the C content of long-term fertilized soils deserves further investigation if we wish to improve our understanding of the C sequestration potential of human-managed grassland soils.
Auteurs, date et publication :
Auteurs Valeria L. Cenini , Dario A. Fornara , Geoffrey McMullan , Nigel Ternan , Rachael Carolan , Michael J. Crawley , Jean-Christophe Clément , Sandra Lavorel
Publication : Soil Biology and Biochemistry
Date : 2025
Volume : 96
Pages : 198-206
Catégorie(s)
#CNRS #Lautaret #UGARésumé
This study has been performed in the framework of a research program aiming to develop a low-cost aerial sensor for the monitoring of cyanobacteria in freshwater ecosystems that could be used for early detection. Several empirical and mechanistic remote-sensing tools have been already developed and tested at large scales and have proven useful in monitoring cyanobacterial blooms. However, the effectiveness of these tools for early detection is hard to assess because such work requires the detection of low concentrations of characteristic pigments amid complex ecosystems exhibiting several confounding factors (turbidity, blooms of other species, etc.). We developed a framework for performing high-throughput measurements of the absorbance and reflectance of small volumes (∼ = 20 mL) of controlled mixtures of phytoplankton species and studied the potential of this framework to validate remote-sensing proxies of cyanobacteria concentration. The absorption and reflectance spectra of single and multiple cultures carried a specific signal that allowed for the quantitative analysis of culture mixes. This specific signal was shown to be related to known pigment absorbance spectra. The concentrations of chlorophyll-a and -b, phycocyanin and phycoerythrin could be obtained from direct absorbance measurements and were correlated with the concentration obtained after pigment extraction (R2 ≥ 0.96 for all pigments). A systematic test of every possible two-band and three-band normalized difference between optical indices was then performed, and the coincidental correlation with chlorophyll-b (absent in cyanobacteria) was used as an indicator of non-specificity. Two-band indices were shown to suffer from non-specificity issues and could not yield strong and specific relationships with phycocyanin or phycoerythrin (maximum R2 0.8).
Auteurs, date et publication :
Auteurs Gabriel Hmimina , Florence D. Hulot , Jean François Humbert , Catherine Quiblier , Kevin Tambosco , Bruno J. Lemaire , Brigitte Vinçon-Leite , Louise Audebert , Kamel Soudani
Publication : Water Research
Date : 2019
Volume : 148
Pages : 504-514
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENS #PLANAQUARésumé
Aim: Our understanding of the mechanisms that maintain forest diversity under changing climate can benefit from knowledge about traits that are closely linked to fitness. We tested whether the link between traits and seed number and seed size is consistent with two hypotheses, termed the leaf economics spectrum and the plant size syndrome, or whether reproduction represents an independent dimension related to a seed size–seed number trade-off.
Auteurs, date et publication :
Auteurs Michal Bogdziewicz , Marie‐Claire Aravena Acuña , Robert Andrus , Davide Ascoli , Yves Bergeron , Daniel Brveiller , Thomas Boivin , Raul Bonal , Thomas Caignard , Maxime Cailleret , Rafael Calama , Sergio Donoso Calderon , J. Julio Camarero , Chia‐Hao Chang‐Yang , Jerome Chave , Francesco Chianucci , Natalie L. Cleavitt , Benoit Courbaud , Andrea Cutini , Thomas Curt
Publication : Global Ecology and Biogeography
Date : 2025
Volume : 32
Issue : 5
Pages : 683-694