Résumé
Clonostachys (Bionectriaceae, Hypocreales) species are common soil-borne fungi, endophytes, epiphytes, and saprotrophs. Sexual morphs of Clonostachys spp. were placed in the genus Bionectria, which was further segregated into the six subgenera Astromata, Bionectria, Epiphloea, Myronectria, Uniparietina, and Zebrinella. However, with the end of dual nomenclature, Clonostachys became the single depository for sexual and asexual morphtypified species. Species of Clonostachys are typically characterised by penicillate, sporodochial, and, in many cases, dimorphic conidiophores (primary and secondary conidiophores). Primary conidiophores are mononematous, either verticillium-like or narrowly penicillate. The secondary conidiophores generally form imbricate conidial chains that can collapse to slimy masses, particularly on sporodochia. In the present study, we investigated the species diversity within a collection of 420 strains of Clonostachys from the culture collection of, and personal collections at, the Westerdijk Fungal Biodiversity Institute in Utrecht, the Netherlands. Strains were analysed based on their morphological characters and molecular phylogeny. The latter used DNA sequence data of the nuclear ribosomal internal transcribed spacer regions and intervening 5.8S nrDNA (ITS) and partial 28S large subunit (LSU) nrDNA and partial protein encoding genes including the RNA polymerase II second largest subunit (RPB2), translation elongation factor 1-alpha (TEF1) and β-tubulin (TUB2). Based on these results, the subgenera Astromata, Bionectria, Myronectria and Zebrinella are supported within Clonostachys. Furthermore, the genus Sesquicillium is resurrected to accommodate the former subgenera Epiphloea and Uniparietina. The close relationship of Clonostachys and Sesquicillium is strongly supported as both are inferred phylogenetically as sister-genera. New taxa include 24 new species and 10 new combinations. Recognition of Sesquicillium distinguishes species typically forming a reduced perithecial stroma superficially on plant tissue from species in Clonostachys often forming well-developed, through bark erumpent stromata. The patterns of observed perithecial wall anatomies, perithecial wall and stroma interfaces, and asexual morph diversifications described in a previously compiled monograph are used for interpreting ancestral state reconstructions. It is inferred that the common ancestor of Clonostachys and Sesquicillium may have formed perithecia superficially on leaves, possessed a perithecial wall consisting of a single region, and formed intercalary phialides in penicilli of conidiophores. Character interpretation may also allow hypothesising that diversification of morphs occurred then in the two genera independently and that the frequently stroma-linked Clonostachys morphs evolved together with the occupation of woody host niches and mycoparasitism.
Auteurs, date et publication :
Auteurs L. Zhao , J.Z. Groenewald , M. Hernández-Restrepo , H.-J. Schroers , P.W. Crous
Publication : Studies in Mycology
Date : 2023
Volume : 105
Issue : 1
Pages : 204-265
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Microalgae remain an exciting target for biotechnology as they offer a largely unexploited reservoir of novel and valuable bioactive compounds. Strain improvement programs are an expanding research field aiming to multiply microalgal potential. This study evaluates the genetic diversity created in populations of the diatom Phaeodactylum tricornutum subjected to random mutagenesis. We explored the genetic diversity using genotyping-by-sequencing (GBS) to estimate and compare the impact of the most common chemical mutagen (ethyl methanesulfonate, EMS). Five microalga populations obtained following EMS treatment had survival rates between 1 and 98 %. High genetic diversity was obtained for only one of these P. tricornutum populations, with a survival rate close to 30 %.
Auteurs, date et publication :
Auteurs Judith Rumin , Grégory Carrier , Catherine Rouxel , Aurélie Charrier , Virginie Raimbault , Jean-Paul Cadoret , Gaël Bougaran , Bruno Saint-Jean
Publication : Algal Research
Date : 2023
Volume : 74
Pages : 103148
Catégorie(s)
#CNRS #EcoGenO #Université de RennesRésumé
To study soil with a view to ecosystems, researchers iterate between experiments in the lab, the field and controlled environments.
Auteurs, date et publication :
Auteurs Vivien Marx
Publication : Nature Methods
Date : 2023
Volume : 20
Issue : 8
Pages : 1131-1134
Catégorie(s)
#CNRS #Ecotron de MontpellierRésumé
Dans le cadre du programme Investissements d’avenir « Infrastructures nationales de biologie et santé» relatif à l’action « Santé et Biotechnologies » lancé en 2011 par le Commissariat Général à l’Investissement (CGI), le Ministère de l’Enseignement Supérieur et de la Recherche et I ’Agence Nationale de la Recherche (ANR), le CNRS, l’INRA et l’UJF se sont associés pour déposer un projet intitulé « Analyse et Expérimentation sur les Ecosystèmes – Service (AnaEE-S) » devenu par la suite AnaEE France. La présente charte a pour objet de définir les modalités d’accès au service qui est proposé par l’Infrastructure AnaEE France et fixer les droits et obligations des utilisateurs.
Auteurs, date et publication :
Auteurs Marion Bousquet , Christine Schrive , André Chanzy , Jean-François Le Galliard , Christian Pichot , Jacques Roy , Thierry Caquet , Serge Aubert , Laurent Saint-André , Franck Delbart , Didier Azam , Cécile Callou , Berndt Zeller , Jean Clobert
Date : 2023
Catégorie(s)
#CNRS #Coordination AnaEE #INRAERésumé
Abstract. Saharan dust outbreaks have profound effects on ecosystems, climate, human health, and the cryosphere in Europe. However, the spatial deposition pattern of Saharan dust is poorly known due to a sparse network of ground measurements. Following the extreme dust deposition event of February 2021 across Europe, a citizen science campaign was launched to sample dust on snow over the Pyrenees and the European Alps. This somewhat improvised campaign triggered wide interest since 152 samples were collected from the snow in the Pyrenees, the French Alps, and the Swiss Alps in less than 4 weeks. Among the 152 samples, 113 in total could be analysed, corresponding to 70 different locations. The analysis of the samples showed a large variability in the dust properties and amount. We found a decrease in the deposited mass and particle sizes with distance from the source along the transport path. This spatial trend was also evident in the elemental composition of the dust as the iron mass fraction decreased from 11 % in the Pyrenees to 2 % in the Swiss Alps. At the local scale, we found a higher dust mass on south-facing slopes, in agreement with estimates from high-resolution remote sensing data. This unique dataset, which resulted from the collaboration of several research laboratories and citizens, is provided as an open dataset to benefit a large community and to enable further scientific investigations. Data presented in this study are available at https://doi.org/10.5281/zenodo.7969515 (Dumont et al., 2022a).
Auteurs, date et publication :
Auteurs Marie Dumont , Simon Gascoin , Marion Réveillet , Didier Voisin , François Tuzet , Laurent Arnaud , Mylène Bonnefoy , Montse Bacardit Peñarroya , Carlo Carmagnola , Alexandre Deguine , Aurélie Diacre , Lukas Dürr , Olivier Evrard , Firmin Fontaine , Amaury Frankl , Mathieu Fructus , Laure Gandois , Isabelle Gouttevin , Abdelfateh Gherab , Pascal Hagenmuller
Publication : Earth System Science Data
Date : 2023
Volume : 15
Issue : 7
Pages : 3075-3094
Catégorie(s)
#CNRS #Lautaret #UGARésumé
An R package to compute DO correction factors for HOBO sensors calibrations, and append new files to old files. Specifically written for PLANAQUA mesocosm lakes, at the CEREEP-Ecotron (France).
Auteurs, date et publication :
Auteurs Rosalie Bruel
Date : 2023
Catégorie(s)
#CNRS #ENS #PLANAQUARésumé
Weaning is a critical period for pigs. Some plant extracts showing antioxidant, anti-inflammatory or anti-bacterial properties, provided to piglets and/or their dam, may improve piglets' robustness at weaning, thus reducing the need for antobiotics. This study investigated the effects of a maternal and/or a direct supplementation of piglets with a combination of plant extracts on sow and piglet performance and their metabolic, immune, inflammatory and oxidative status during lactation and around weaning. Sixty-four sows were assigned to the control or treated group. Treated sows were supplemented with a powdered plant extracts supplement daily top-dressed on feed from day of gestation (DG) 106 to day of lactation (DL) 28 and a liquid solution top-dressed on feed on DG109. Within each sow group, litters were divided into two groups: a control piglet group and a treated piglet group. A single dose of a liquid solution was orally given to piglets in the treated piglet group. Piglets were weaned on DL28. Blood samples were collected from sows on DG94, DG112 and DL26 and from 2 piglets per litter on DL3, DL14, DL25 and 5 d post-weaning to analyze indicators of metabolic, immune, inflammatory and oxidative status. Colostrum and milk samples were collected at farrowing, DL6 and 26. Maternal supplementation had no effect on sow metabolic, immune, inflammatory and oxidative status except for fewer lymphocytes on DG112 (P < 0.05) and a lower plasma concentration of non-esterified fatty acids on DL26 (P < 0.05). Maternal supplementation tended to decrease dry matter and gross energy (P < 0.10) and reduced fat and haptoglobin concentrations (P < 0.01) in milk on DL26. Maternal supplementation had no effect on piglets' growth performance and blood indicators during lactation and around weaning. On DL25, the direct supplementation of piglets decreased their neutrophils proportion (P < 0.05), increased the expression of genes encoding pro- and anti-inflammatory cytokines in whole blood culture in response to LPS (P < 0.05) and tended to decrease the oxidative stress index (P = 0.06). After weaning, these beneficial effects were no longer observed but the supplementation improved piglets' growth performance during the post-weaning period (P < 0.05). Plant extract supplementation could thus modify the composition of mammary secretions and improve post-weaning performance of piglets potentially related to the modification of their immune and oxidative status before weaning.
Auteurs, date et publication :
Auteurs Lucile Herve , Hélène Quesnel , Amaury Greuter , Laurent Hugonin , Elodie Merlot , Nathalie Le Floc'h
Publication : Journal of Animal Science
Date : 2023
Pages : skad282
Catégorie(s)
#CNRS #EcoGenO #Université de RennesRésumé
Electroporation is an increasingly common technique used for exogenous gene expression in live animals, but protocols are largely limited to traditional laboratory organisms. The goal of this protocol is to test
in vivo
electroporation techniques in a diverse array of tadpole species. We explore electroporation efficiency in tissue-specific cells of five species from across three families of tropical frogs: poison frogs (Dendrobatidae), cryptic forest/poison frogs (Aromobatidae), and glassfrogs (Centrolenidae). These species are well known for their diverse social behaviors and intriguing physiologies that coordinate chemical defenses, aposematism, and/or tissue transparency. Specifically, we examine the effects of electrical pulse and injection parameters on species- and tissue-specific transfection of plasmid DNA in tadpoles. After electroporation of a plasmid encoding green fluorescent protein (GFP), we found strong GFP fluorescence within brain and muscle cells that increased with the amount of DNA injected and electrical pulse number. We discuss species-related challenges, troubleshooting, and outline ideas for improvement. Extending
in vivo
electroporation to non-model amphibian species could provide new opportunities for exploring topics in genetics, behavior, and organismal biology.
Auteurs, date et publication :
Auteurs Jesse Delia , Maiah Gaines-Richardson , Sarah C. Ludington , Najva Akbari , Cooper Vasek , Daniel Shaykevich , Lauren A. O’Connell , Michael Schubert
Publication : PLOS ONE
Date : 2023
Volume : 18
Issue : 8
Pages : e0289361
Catégorie(s)
#CNRS #FORET NouraguesRésumé
The determinants of phyllosphere microbial communities are drawing much attention given their functional importance for their plant host fitness and health. Identifying these determinants remains challenging in neotropical forests, considering the diversity of the tree hosts and the strong vertical heterogeneity of abiotic conditions within the canopy and at the scale of the leaf. Here, we studied fungal and bacterial communities living in the endophytic and epiphytic phyllosphere in tree species across vertical gradients, from the top of the canopy to the ground. We used DNA metabarcoding to characterize microbial communities and measured abiotic variables and foliar traits to characterize environmental heterogeneity. The assembly of fungal communities was more driven by deterministic processes compared with bacteria, with endo- and epiphytic communities being similarly shaped by the host identity and unmeasured parameters. In contrast, in bacterial communities, the relative importance of deterministic processes decreased from endophytic to epiphytic communities. Bacterial epi- and endophytic communities were partly and differently determined by the position within the canopy, the host identity, and leaf traits, suggesting an effect of the vertical gradient and a stronger selection in the inner tissues of the leaf than on its surface. The tree host exerts a selective pressure on microbial communities but the leaf as microhabitat also contributes significantly to the assembly of microbial communities. Discrepancies exist between fungi and bacteria that probably reflect different life-history traits and ecological strategies, emphasizing the need to study these communities jointly if we are to fully understand plant–phyllosphere interactions.
Auteurs, date et publication :
Auteurs Heidy Schimann , Corinne Vacher , Sabrina Coste , Eliane Louisanna , Tania Fort , Lucie Zinger
Publication : Phytobiomes Journal
Date : 2023
Pages : PBIOMES-02-23-0013-R
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Earthworms are known to stimulate soil greenhouse gas (GHG) emissions, but
the majority of previous studies have used simplified model systems or
lacked continuous high-frequency measurements. To address this, we
conducted a two-year study using large lysimeters (5 m2 area and 1.5 m
soil depth) in an ecotron facility, continuously measuring ecosystem-level
CO2, N2O, and H2O fluxes. We investigated the impact of endogeic and
anecic earthworms on GHG emissions and ecosystem water use efficiency
(WUE) in a simulated agricultural setting. Although we observed transient
stimulations of carbon fluxes in the presence of earthworms, cumulative
fluxes over the study indicated no significant increase in CO2 emissions.
Endogeic earthworms reduced N2O emissions during the wheat culture
(-44.6%), but this effect was not sustained throughout the experiment. No
consistent effects on ecosystem evapotranspiration or WUE were found. Our
study suggests that earthworms do not significantly contribute to GHG
emissions over a two-year period in experimental conditions that mimic an
agricultural setting. These findings highlight the need for realistic
experiments and continuous GHG measurements.
Auteurs, date et publication :
Auteurs Oswaldo Forey , Alexandru Milcu , Damien Landais , Joana Sauze , European Ecotron Of Montpellier*
Date : 2023