Résumé
Ranunculus glacialis leaves were tested for their plastid terminal oxidase (PTOX) content and electron flow to photorespiration and to alternative acceptors. In shade-leaves, the PTOX and NAD(P)H dehydrogenase (NDH) content were markedly lower than in sun-leaves. Carbon assimilation/ light and Ci response curves were not different in sun- and shade-leaves, but photosynthetic capacity was the highest in sun-leaves. Based on calculation of the apparent specificity factor of ribulose 1·5-bisphosphate carboxylase/oxygenase (Rubisco), the magnitude of alternative electron flow unrelated to carboxylation and oxygenation of Rubisco correlated to the PTOX content in sun-, shade- and growth chamberleaves. Similarly, fluorescence induction kinetics indicated more complete and more rapid reoxidation of the plastoquinone (PQ) pool in sun- than in shade-leaves. Blocking electron flow to assimilation, photorespiration and the Mehler reaction with appropriate inhibitors showed that sun-leaves were able to maintain higher electron flow and PQ oxidation. The results suggest that PTOX can act as a safety valve in R. glacialis leaves under conditions where incident photon flux density (PFD) exceeds the growth PFD and under conditions where the plastoquinone pool is highly reduced. Such conditions can occur frequently in alpine climates due to rapid light and temperature changes.
Auteurs, date et publication :
Auteurs Constance Laureau , Rosine De Paepe , Gwendal Latouche , Maria Moreno-Chacón , Giovanni Finazzi , Marcel Kuntz , Gabriel Cornic , Peter Streb
Publication : Plant, Cell & Environment
Date : 2025
Volume : 36
Issue : 7
Pages : 1296-1310
Catégorie(s)
#CNRS #Lautaret #UGAAuteurs, date et publication :
Auteurs Andrius Pašukonis , Ian Warrington , Max Ringler , Walter Hödl
Publication : Biology letters
Date : 2025
Volume : 10
Issue : 11
Pages : 20140642
Catégorie(s)
#ANR-Citation #CNRS #FORET NouraguesRésumé
Artisanal and small-scale gold mining (ASGM) has become a major threat for Neotropical forests. This technique for obtaining gold is a substantial driver of small-scale deforestation and the largest contributor of Hg emissions to both the atmosphere and freshwater systems globally. Previous studies have demonstrated the impacts of Hg accumulation on various aquatic ecosystems and organisms. However, its consequences in other, more discrete systems such as phytotelmata (water -holding plant structures), and the organisms therein, have so far gone unnoticed. Here, we show high concentrations of Hg (mean +/- SD: 1.43 +/- 2.19 ppm) in phytotelmata and other small pools, the aquatic microenvironments used by the Neotropical poison frog Dendrobates tinctorius as tadpolerearing sites. In 17 % of the cases, we detected Hg concentrations above the severe effect level (SEL = 2 ppm) for freshwater sediments. Hg concentrations varied depending on pool characteristics and tended to increase in proximity to known ASGM sites. We did not find an effect of Hg concentration on the number of D. tinctorius tadpoles in a given pool. Tadpoles were found in pools with concentrations of up to 8.68 ppm, suggesting that D. tinctorius fathers do not avoid pools with high Hg levels for tadpole deposition. While further research is needed to determine the potential effects of Hg on tadpole development, we found an intriguing tendency for tadpoles in later developmental stages to have lower body condition when occurring in pools with higher Hg concentrations. Our findings provide evidence of relevant Hg concentrations in the terrestrial water systems used by phytotelm-breeding anurans, and highlight the need of further field and experimental studies investigating the implications of Hg contamination for tadpole development and behaviour and the overall conservation of Amazonian biodiversity.
Auteurs, date et publication :
Auteurs Lia Schlippe-Justicia , Jeremy Lemaire , Carolin Dittrich , Martin Mayer , Paco Bustamante , Bibiana Rojas
Publication : SCIENCE OF THE TOTAL ENVIRONMENT
Date : 2024
Volume : 912
Catégorie(s)
#ANR-Citation #CNRS #FORET NouraguesRésumé
Ce document définit la politique d’accès à l'infrastructure nationale AnaEE France. Il s’appuie notamment sur les chartes d’accès aux services de l’infrastructure et identifie les outils, modalités et règles permettant l’accès aux services de l’infrastructure nationale AnaEE France.
Auteurs, date et publication :
Auteurs Alyssa Clavreul , Marion Bousquet , André Chanzy , Jean-François Le Galliard , Christian Pichot , Florent Massol , Christine Schrive
Date : 2022
Catégorie(s)
#CNRS #Coordination AnaEE #INRAERésumé
Ce document définit la politique des données acquises à partir des services de l'infrastructure nationale AnaEE-France et leur modalité de diffusion. Nous rappelons que ces services couvrent l’accès aux plateformes expérimentales, la production d’analyses pour caractériser les écosystèmes, la mise à disposition d’instruments et l’accès aux plateformes de modélisation. Ce document ne traite pas des données générées par des modèles utilisant les plateformes de modélisation qui font l'objet d'un document spécifique.
Auteurs, date et publication :
Auteurs André Chanzy , Christian Pichot , Jean-François Le Galliard , Marion Bousquet , Christine Schrive
Date : 2021
Catégorie(s)
#CNRS #Coordination AnaEE #INRAERésumé
Le présent document constitue un cadre définissant les principes généraux d'utilisation, de stockage, de diffusion et de réutilisation des données. Il pourra évoluer pour permettre un alignement avec la politique institutionnelle du CNRS ou celle proposée plus largement aux niveaux national et européen. Il s'adresse principalement aux producteurs et utilisateurs des données issues des dispositifs et infrastructures de l'Institut Écologie et Environnement (INEE) du CNRS. Les personnels des structures opérationnelles de recherche multi-tutelles peuvent être amenés à appliquer d'autres recommandations, en fonction de leur implantation. Les principes énoncés suivent ceux de la politique de Science Ouverte : "aussi ouvert que possible, fermé autant que nécessaire". Lorsque les conditions d'ouverture des données ne peuvent être remplies pour des motifs d'ordre juridique ou de confidentialité (par exemple en cas de présence de données sensibles ou personnelles), ces conditions doivent être clairement établies.
Auteurs, date et publication :
Auteurs Cécile Callou , Isabelle Charpentier , Alyssa Clavreul , Hénon Amandine , Dominique Joly , Emilie Lerigoleur , Mathieu Massaviol , Corinne Pardo
Date : 2022
Catégorie(s)
#BBEES #CNRS #ISIARésumé
Understanding the assembly rules of mycorrhizal fungi is crucial, given their tremendous importance in plant nutrition and health. Differentiation in plant-associated arbuscular mycorrhizal fungi (AMF) is likely driven by a host-preference effect. Coexisting plant species may then affect a focal plant microbiota through fungal dispersal among plants, and plant preferential recruitment of AMF. Both mechanisms are likely shaped by the plant's phylogenetic and functional strategies. We expected that (a) the structure of AMF assemblages associated with a focal plant depends on the identity of the neighbouring plant species; (b) this effect would be predicted by the phylogenetic and functional similarity between the focal and neighbouring plant species. These predictions were tested during the first stages of growth, by simulating the early development of plants within a community Using an experimental matrix-focal plant species design testing 15 neighbouring plants from five taxonomic families, we demonstrated that the neighbouring plants provided different species pools for the focal plant, Medicago truncatula, and influenced AMF communities associated with focal plant, especially in terms of richness but not relative evenness. Medicago truncatula grown with Brassicaceae or other Poaceae species displayed respectively no or low AMF richness compared to those grown with Rosaceae and Asteraceae species. These effects were weakly dependent on the phylogenetic distance from the neighbouring plant but were predicted by the functional proximity. AMF assemblages were enriched and bore more resemblance to the neighbouring plants when the neighbouring plants were functionally dissimilar from the focal one. Functional dissimilarity was only a significant predictor when based on traits characterizing the nutrient use and uptake strategy rather than on a more integrated growing strategy of the plant. Microbiota composition was shown to be dependent on the identity of the neighbouring plant, particularly on its functional below-ground niche. At the colonization stage, when the plant arrives in a community, plant mycobiota might be influenced by the spatial distribution of plants already present in the community. This work suggests a new view of the concept of niche partitioning in space for plants based on microorganism–plant interactions. A free Plain Language Summary can be found within the Supporting Information of this article.
Auteurs, date et publication :
Auteurs Cendrine Mony , Valentin Gaudu , Claire Ricono , Olivier Jambon , Philippe Vandenkoornhuyse
Publication : Functional Ecology
Date : 2025
Volume : 35
Issue : 8
Pages : 1768-1782
Catégorie(s)
#CNRS #EcoGenO #Université de RennesRésumé
Plant species influence soil microbial communities, mainly through their functional traits. However, mechanisms underlying these effects are not well understood, and in particular how plant/ microorganism interactions are affected by plant identities and/or environmental conditions. Here, we performed a greenhouse experiment to assess the effects of three plant species on arbuscular mycorrhizal fungal (AMF) colonization, bacterial potential nitrification (PNA) and denitrification activities (PDA) through their functional traits related to nitrogen acquisition and turnover. Three species with contrasting functional traits and strategies (from exploitative to conservative), Dactylis glomerata (L.), Bromus erectus (Hudson) and Festuca paniculata (Schinz and Tellung), were cultivated in monocultures on soil grassland with or without N fertilization. Fertilization impacted some plant traits related to nutrient cycling (leaf and root N concentration, root C:N) but did not affect directly microbial parameters. The highest PDA and PNA were observed in D. glomerata and F. paniculata monocultures, respectively. The highest AMF colonization was obtained for F. paniculata, while B. erectus exhibited both the lowest AMF colonization and bacterial activities. Bacterial activities were influenced by specific above-ground plant traits across fertilization treatments: above-ground biomass for PDA, shoot:root ratio and leaf C:N ratio for PNA. Mycorrhizal colonization was influenced by below-ground traits either root dry matter content or root C:N. Hence, AMF colonization and bacterial activities were impacted differently by species-specific plant biomass allocation, root traits and nutrient requirement. We suggest that such effects may be linked to distinct root exudation patterns and plant abilities for nutrient acquisition and/or nutrient competition.
Auteurs, date et publication :
Auteurs N. Legay , F. Grassein , M.N. Binet , C. Arnoldi , E. Personeni , S. Perigon , F. Poly , T. Pommier , J. Puissant , J.C. Clément , S. Lavorel , B. Mouhamadou
Publication : Applied Soil Ecology
Date : 2025
Volume : 98
Pages : 132-139
Catégorie(s)
#CNRS #Lautaret #UGAAuteurs, date et publication :
Auteurs P. Lamarque , S. Lavorel , M. Mouchet , F. Quetier
Publication : Proceedings of the National Academy of Sciences
Date : 2014
Volume : 111
Issue : 38
Pages : 13751-13756
Catégorie(s)
#CNRS #Lautaret #UGAAuteurs, date et publication :
Auteurs Antoine Gardarin , Éric Garnier , Pascal Carrère , Pablo Cruz , Donato Andueza , Anne Bonis , Marie-Pascale Colace , Bertrand Dumont , Michel Duru , Anne Farruggia , Stéphanie Gaucherand , Karl Grigulis , Éric Kernéïs , Sandra Lavorel , Frédérique Louault , Grégory Loucougaray , François Mesléard , Nicole Yavercovski , Elena Kazakou , Jennifer Firn
Publication : Journal of Applied Ecology
Date : 2025
Volume : 51
Issue : 5
Pages : 1207-1217