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The international protection of geographical indications: A complex bowl of spaghetti lacking the flavour of a collectively defined and controlled product specification? [Editorial]
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616097/)International audienc
Host and microbial defenses against fungal invaders in a fungus‐farming termite
No full textInternational audienceFungus farming in termites is vulnerable to invasions by opportunistic and specialized fungi that may compromise the Termitomyces fungal crop that these termites rely on for food. Both termite and symbiont defenses contribute to suppressing such fungal infections, and here we build on past efforts to help understand these defenses. We demonstrate that gardens without Macrotermes annandalei termites are rapidly colonized by weedy fungi, initially dominated by opportunistic Aspergillus and Trichoderma molds and later by co‐evolved Xylaria that outcompete these molds. In some cases, termite presence suppresses molds but not Xylaria infections. We then demonstrate that termite burying behavior, a defense response to weeds, increases in the presence of Termitomyces , suggesting that the perception of weeds as threats is most pronounced when there is a risk of garden exposure. The burying response was strongest toward Aspergillus and Trichoderma , suggesting that coevolved Xylaria may to some extent evade this defense. Lastly, we document antifungal properties of Bacillus and Burkholderia bacteria, and 21 fungi isolated from the symbiotic environment, in support that both hosts and fungistatic microbes contribute to keeping fungal gardens free from unwanted fungi. Although our findings suggest a multi‐partnered defense, further work is needed to determine the compounds responsible and their ecological significance in protecting termite gardens
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No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616046/)International audienc
Canopy Carbon‐ and Water‐Use Efficiencies in Response to Temperature and Water Deficit for Wheat
No full textInternational audienceThe frequency and intensity of extreme climatic events increase the complexity in assessing climate change impacts on (agro) ecosystem functions and crop production. A better understanding of carbon and water fluxes for crop plants under climate change requires research based on direct canopy-scale measurements. By analysing a canopy gas exchange data set synthesised from 8 years' experimentation under semi-field conditions for the post-anthesis period of five wheat genotypes, we examined canopy carbon and water fluxes as well as carbon use efficiency (CUE) and water use efficiency (WUE) under varying environmental conditions. CUE was variable, and was negatively affected by high temperatures. Moreover, CUE responded differently to daily, daytime, and nighttime temperatures, and was most sensitive to nighttime temperatures. The response of WUE to increasing temperatures was dominated by the response of carbon fluxes, while the relative contribution of water fluxes to WUE responses increased under water deficit. WUE based on gross and net photosynthesis responded differently to environmental variables, primarily due to the differences in CUE. The findings increase our understanding of canopy carbon and water fluxes under various environmental conditions and highlight the necessity for future efforts to improve crop CUE and WUE under climate change.</div
Diversity of Sordariales Fungi: Identification of Seven New Species of Naviculisporaceae Through Morphological Analyses and Genome Sequencing
No full textInternational audienceThanks to next-generation sequencing (NGS) technologies, the diversity of fungi can now be investigated through the analysis of their genome sequences. Naviculisporaceae is a family within the Sordariales, whose diversity is not well-known, with only one genome sequence published for this family. Here, we report on the isolation and cultivation of 20 new strains of Naviculisporaceae. Their genome sequences, as well as those of the five commercially available strains, were determined, thus providing complete genome sequences for 25 new Naviculisporaceae strains. Species delimitation was conducted using a combination of (1) ITS + LSU phylogenetic analysis of the new isolates along with other known species of the family, (2) comparisons between DNA barcode sequences of the new strains with those of the known species, and (3) average genome-wide nucleotide identity calculation. We built a phylogenomic tree and studied the organization of the mating-type locus. In vitro fruiting was obtained for 16 strains, enabling the definition of seven new species, namely Pseudorhypophila gallica, Pseudorhypophila guyanensis Rhypophila alpibus, Rhypophila brasiliensis, Rhypophila camarguensis, Rhypophila reunionensis and Rhypophila thailandica, as well as two new combinations, namely Pseudorhypophila latipes and Pseudorhypophila oryzae. Eight strains for which in vitro fruiting was not obtained may belong to additional new species. These results expand the known diversity of the Naviculisporaceae and greatly enlarge the genomic data available for the family
Mise à jour des estimations démographiques et des effectifs de la population de loups en France lors de l'hiver 2024/25
No full textLa population de loups (Canis lupus) en France fait l'objet d'un suivi annuel réalisé par le Réseau Loup-Lynx, piloté par l'Office Français de la Biodiversité. Ce rapport actualise les paramètres démographiques et les estimations d'effectifs à la suite de la campagne de terrain de l'hiver 2024/25. Comme déjà appliqué depuis l'hiver 2023/24, la collecte des données s'appuie sur un plan d'échantillonnage définissant, pour des mailles de 10*10km, des objectifs de récolte d'indices biologiques afin d'homogénéiser la prospection dans les zones de présence historiques. Le génotypage de l'ADN issu des indices biologiques collectés sur tout le territoire français (fèces, poils, urines, sang et dépouilles des loups morts) permet d'obtenir l'identité génétique des individus. Cette identité constitue la donnée de base pour l'estimation des paramètres démographiques et des effectifs. Comme les années précédentes, les méthodes de capture-recapture ont été utilisées pour prendre en compte la détection partielle et hétérogène des individus de la population. Les estimations d'effectifs montrent que le nombre de loups en France lors de l'hiver 2024/25 se situe vraisemblablement entre 989 et 1187 individus. Ces deux valeurs correspondent aux bornes basse et haute de l'intervalle de confiance à 95%. Bien que l'effectif moyen montre une légère hausse -passant de 1013 lors de l'hiver 2023/24 à 1082 lors de l'hiver 2024/25 -il n'est pas possible de conclure à une augmentation des effectifs entre ces deux années puisque les intervalles de confiance (IC) associés se chevauchent (2023/24 : 920-1125 ; 2024/25 : 989-1187). Les conclusions sur la tendance démographique de la population doivent se faire sur des séries pluriannuelles pour identifier les trajectoires démographiques des populations, particulièrement au vu du degré d'incertitude associé à ces estimations. La connaissance des paramètres démographiques éclaire aussi ces tendances. La mise à jour des estimations de survie annuelle confirme la dynamique observée précédemment : le taux de survie passe de 71 % (IC à 95 % : 67-76 %) sur la période 2014-2018 à 66 % (IC 95 % : 59-73 %) sur la période 2019-2025. Cette dernière période correspond au changement de régime de prélèvement dérogatoire qui est passé d'environ 10% de la population sur la période 2014-18 à 19% en 2019-25. Avec de tels niveaux de survie, une stabilisation de la population est attendue, ce que semble refléter les estimations d'effectifs des quatre dernières années
Expérimentation de biostimulants fermentés auto-produits sur la vigueur de porte-greffes et la fertilité du sol : impacts agronomiques, faisabilité et durabilité à la ferme de la Noria
No full textPlant-based extracts are biostimulants rich in active compounds and nutrients. Their aim is to stimulate crop growth, enhance tolerance to stress, and promote soil microbial communities. The effects of fermented extracts and Fermented Forest Litter (LiFoFer) on crops remain poorly studied and not fully characterized, although some trends have emerged in the literature. In the current context of reducing external inputs and enhancing agricultural sustainability, this study aimed to evaluate the effects of fermented biostimulants—nettle and comfrey fermented extracts, and LiFoFer—on the vigor of 40 young fruit tree rootstocks compared with 40 untreated controls, as well as their impacts on soil fertility at the base of the trees. Several growth variables were measured: main stem growth, trunk diameter increase over one year, secondary shoot biomass, leaf chlorophyll content, and root development. Soil variables included organic matter decomposition, microbial respiration, aggregate stability, residual nitrogen, and soil moisture. Results showed no significant effect of the biostimulants on either trees or soil, except for a single trend toward improved aggregate stability (+6%) in the 2–10 cm horizon. The experiment was limited by low statistical power and high variability among rootstock types. Multi-year observations would be necessary to detect potential effects on plant growth and soil properties, which evolve slowly. Nevertheless, these fermented preparations represent a valuable tool for enhancing farm autonomy and a major lever for improving system resilience.Les extraits à base de plantes sont des biostimulants riches en composés actifs et en nutriments. Ils visent à la fois à stimuler la croissance des cultures, à les protéger des stress et à stimuler les communautés microbiennes du sol. La Litière de Forêt Fermentée (aussi appelée LiFoFer) n’est pas légalement considérée comme un biostimulant mais est utilisée en tant que tel. Encore peu étudiés, les effets des extraits fermentés et de la LiFoFer sur les cultures ne sont pas totalement caractérisés, mais des tendances apparaissent dans les études. Dans un contexte de recherche d’autonomie en intrants et de durabilité agricole, la présente étude cherche à montrer l’effet de biostimulants fermentés - extraits fermentés d’ortie et de consoude, et LiFoFer - sur la vigueur de 40 jeunes porte-greffes de fruitiers en comparaison à 40 autre non-traités avec ces produits, ainsi que les impacts sur la fertilité du sol au pieds de ces arbres fruitiers. Ainsi, plusieurs variables de croissances sont mesurées : croissance de la tige principale, croissance du diamètre du tronc sur une année, biomasse des rameaux secondaires, teneur en chlorophylle des feuilles et développement racinaire. Les variables de sol étudiées sont : la décomposition de la matière organique, la respiration microbienne, la stabilité des agrégats de sol, le reliquat azoté, l’humidité. Les résultats ne montrent aucun effet significatif des biostimulants sur les arbres et sur le sol. Une seule tendance ressort : une meilleure stabilité des agrégats de l’horizon 2-10 cm de 6%. L’expérimentation manque de puissance statistique : on constate une grande variabilité entre les types de porte-greffes. Des observations pluriannuelles seraient nécessaires pour détecter des effets sur la croissance et le sol, qui évoluent lentement. Néanmoins, ces préparations fermentées représentent un réel outil d’autonomie pour les exploitations agricoles et un levier majeur dans la résilience des systèmes
Temporal transcriptional response of maize roots to heterogeneous water availability reveals a crucial role of Jasmonic Acid in local and systemic signaling
No full textInternational audienc
Establishment, maintenance and consequences of inter-individual transcriptional variability in plants
No full textInternational audienceSurprisingly, differences in phenotypes and gene expression are observed between genetically identical individuals grown in the same environment. While we now have a good knowledge of the source and consequences of transcriptional differences observed between cells, in particular for unicellular organisms, it is still very scarce when it comes to variability between multicellular organisms. Using plants as a model we analysed the establishment, maintenance and consequences of inter-individual transcriptional variability. We showed, for a gene of interest, that differences in expression between plants are established in young seedlings, maintained over several days but not transmitted to the next generation. Our results also indicate that these differences in expression can explain phenotypic variability between plants such as for the root growth. Finally, using a genome-wide approach, we found a co-expression in seedlings for our gene of interest, involved in nitrate nutrition, and genes involved in photosynthesis. All in all, our study suggests that a global coordination of the genes involved in the carbon/nitrate balance in plants is established in young seedlings, with differences of this state between plants, and then maintained over time