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First and disturbing records of the bivalve molluscs Potamocorbula amurensis (Schrenck, 1861) and Mulinia lateralis (Say, 1822) in the Bay of Biscay (France)
No full textInternational audienceThe bivalve mollusc Potamocorbula amurensis, a Corbulidae from the Asian coasts, was recorded for the first time in France in September 2023 in the Gironde estuary, and subsequently in September 2024 in Aiguillon Cove and Aytré Bay. In Aytré Bay, it was accompanied by another non-native bivalve not previously reported from French coasts, Mulinia lateralis, a Mactridae from the western Atlantic coasts. These two species were first recorded in Europe in 2018 in the Westerschelde (Netherlands, Belgium) and are known to be potentially highly invasive. Particular attention should be paid to monitor the spread and the establishment of these two euryoecious species along European coasts.</div
BIOSCAN-FR : Surveillance moléculaire de la biodiversité terrestre en France hexagonale et outre mer
No full textNational audienc
Solid-State Stability of Pentobarbital in Fast-Dissolving Suppositories: Implications for Dissolution Behavior and Pediatric Formulation Performance
No full textInternational audienceBackgroundSafe and well-tolerated sedative formulations are essential in pediatric procedural care. Pentobarbital, a short-acting barbiturate, remains widely used for pediatric sedation. However, its oral administration is limited by poor palatability. Rectal administration therefore represents a relevant alternative, provided that formulation stability is ensured. This study evaluated the physicochemical and microbiological stability of fast-dissolving pentobarbital suppositories developed for pediatric use.MethodsSuppositories containing 30 or 60 mg of pentobarbital sodium were formulated with two sodium hydroxide (NaOH) concentrations and stored under refrigerated (5 degrees C) or frozen (-20 degrees C) conditions for up to 180 days. Stability was assessed by macroscopic examination, pH measurement, dissolution testing, mechanical strength, softening time, and microbiological quality. Solid-state changes were analyzed using Raman spectroscopy and X-ray diffraction, and precipitation kinetics were modeled.ResultsRefrigerated storage led to progressive precipitation from day 90, associated with pH decrease and conversion of pentobarbital sodium to its free acid, resulting in incomplete dissolution. In contrast, frozen storage preserved pH, physical integrity, and complete dissolution, even after 30 days at 5 degrees C following thawing. Spectroscopic and diffraction analyses confirmed recrystallization under refrigeration, whereas frozen formulations retained an amorphous structure. Increased NaOH content delayed, but did not prevent, instability at 5 degrees C. All formulations complied with pharmacopeial mechanical and microbiological requirements.ConclusionStorage temperature was the main determinant of stability, with freezing ensuring long-term preservation. NaOH buffering mitigated gelatin acidity and delayed drug conversion, thereby extending shelf life. These findings support further biopharmaceutical and clinical evaluation of pentobarbital suppositories for pediatric sedation
Nutritional adaptation in the marine to freshwater establishment process - how do diet and genotype shape phenotype?
No full textInternational audienceNutrients, including vital organic compounds, vary in availability across ecosystems, with the potential to act as a strong source of selection for traits that increase nutrient acquisition and biosynthesis. Compared to freshwaters, marine ecosystems are much richer in the omega-3 long-chain polyunsaturated fatty acid docosahexaenoic acid (DHA) and thus marine animals establishing new freshwater populations are faced with the challenge of acquiring DHA. However, the relative roles of DHA synthesis capacity and diet in the freshwater establishment process remain unresolved. We used common garden experiments to explore phenotypic responses to dietary nutrient content in threespine sticklebacks (Gasterosteus aculeatus) that Journal of Experimental Biology • Accepted manuscript varied in their genetic capacity for DHA synthesis. We found that diet as well as presumed metabolicbased adaptation to freshwater nutritional environments (population identity) had strong effects on stickleback phenotypes and performance. Sticklebacks enriched with marine-derived fatty acids including DHA grew more and were in better condition compared to controls. Those fed diets with more DHA also accumulated more DHA in muscle tissue. Freshwater sticklebacks accumulated more DHA compared to those from a marine population. However, populations with greater fads2 copy numbers did not consistently have higher performance or DHA accumulation. Together, these results suggest that DHA availability during development can strongly influence phenotypes and performance, with the potential to act as a source of selection. Our findings also suggest that mechanisms beyond the accumulation of fads2 copies, such as plasticity in expression or variation in other DHA synthesis pathway genes, could be important adaptations to the nutritional constraints of freshwater
Bisexual releases are as effective as male‐only releases to control <i>Drosophila suzukii</i> with the sterile insect technique
No full textInternational audienceBACKGROUND: The sterile insect technique (SIT) suppresses insect reproduction by repeatedly releasing sterile insects and allowing them to mate with insects of the same species in the wild. While the classical SIT relies on sterile males mating with wild females, there is a debate regarding the risks and benefits of releasing sterile females along with the sterile males (i.e. bisexual releases). In a replicated cage experiment, we compared the effect of unisexual and bisexual sterile releases of Drosophila suzukii on induced sterility. To ensure field-realism, fertile females -wild-F0 freshly emerged from field-collected sweetcherries -were placed in cages with artificial vegetation and plastic berries.RESULTS: The proportion of fertile females that produced offspring was not significantly different in unisexual and bisexual treatment (45% and 46%, respectively). Excluding females that had not mated (i.e. no sperm in the spermathecae) from the analysis had no influence.CONCLUSION: These results suggest the release of sterile females does not always affect the efficacy of the SIT. Even though additional phenomena may arise when scaling up from cages to the field, we conclude that sorting females with genetic constructs or robotic systems is probably dispensable in D. suzukii SIT, at least when deployed in confined farming systems.</div
La Planète Revisitée des îles de GuadeloupeProgramme d’exploration de la faune et de la flore terrestre et marine sur les îles des Saintes, Marie Galante et La DésiradeRapport intermédiaire 2025
No full textMinimisation de l'utilisation des pesticides en systèmes de grandes cultures et cultures légumières en Hauts-de-France
No full textCe numéro fait suite au carrefour de l'innovation agronomique dédié au résultats des projets DEPHY EXPE 2 - Des systèmes utilisant les pesticides en ultime recours : résultats et enseignements de 6 ans d’expérimentations le 13 mars 2025 co-organisé par Inrae, Agreenium, la cellule d'Animation Nationale du réseau DEPHY Ecophyto et le lycée agricole du Valentin. Sont présenté les résultats des projets DEPHY EXPE 2 arrivant à leur terme en décembre 2024 pour diffuser les connaissances des principaux enseignements de ces essais « systèmes » qui ont éprouvé pendant 6 ans des combinaisons de leviers alternatifs à la lutte chimique pour maîtriser les bioagresseurs des cultures : diversification de l’agroécosystème, méthodes de contrôle biologique, choix de matériel végétal, stratégie d’évitement, prophylaxie… Les modalités de mises en œuvre des alternatives testées, leurs conditions de réussite et de diffusion et leurs impacts sur les performances techniques, économiques et environnementales de systèmes ont été discutées.National audienceMinipest project, conducted over six years, aims at combining several agroecological levers in order to reduce as far as possible the dependence of two cropping systems in the Hauts-de-France region (field crops and vegetable crops) on conventional plant protection products. After five years of experimentation, most of the decision rules have been successfully applied, and the feasibility of the levers has been analyzed. Overall, the technical and agronomic performance of the levers applied and the results in termsof yield and gross margin are satisfactory and promising. However, some of the problems identified are not totally solved with the available technicity, such as onion weed control and the modulation of pest nuisance thresholds according to beneficiary population levels. The encouraging agroeconomic indicators found will allow the transfer of knowledge to producers and trainees.Le projet Minipest, conduit sur une durée de six ans, vise à combiner plusieurs leviers agroécologiques afin de réduire au maximum la dépendance de deux systèmes de culture de la Région Hauts-de-France (grandes cultures et cultures légumières) aux produits phytosanitaires conventionnels. Après cinq années d'expérimentation, la majorité des règles de décision ont été appliquées avec succès et la faisabilité des leviers a été analysée. Dans l'ensemble, la performance technique et agronomique des leviers actionnés et les résultats relatifs aux rendements et à la marge brute sont satisfaisants et prometteurs. Toutefois, certains problèmes constatés ne sont totalement pas solutionnés avec la technicité disponible, comme le désherbage de l'oignon et la modulation des seuils de nuisibilité des insectes ravageurs selon les niveaux de populations des auxiliaires. Les indicateurs technico-économiques encourageants obtenus permettront le transfert des connaissances vers les producteurs et les apprenants
Marine protected areas as living labs ? Lessons learned & future perspectives
No full textInternational audienc
A safari across France: soil fauna insights from a nationwide soil quality monitoring program
No full textInternational audienceSoil biodiversity is fundamental to ecosystem functioning but remains underrepresented in conservation policies and large-scale monitoring. Here, we present RMQS-Biodiversity, a nationwide soil biodiversity survey integrated into the French Soil Quality Monitoring Network (RMQS), and illustrate its potential for soil ecology research. In this pioneer study, we examine three major ecological aspects: (i) how systematic grid-based sampling captures micro-food web patterns using nematode communities, (ii) the spatial turnover of detritivore communities (Collembola, Isopoda, Diplopoda) in response to environmental and geographic gradients, and (iii) the influence of macroecological drivers on predator (Carabidae) morphological traits. Across 69 sites, we identified a few widespread species coexisting with numerous rare taxa, underscoring the value of large-scale surveys for detecting cryptic biodiversity. Nematode indicators revealed high variability in food web structure across land uses, with increased facultative phytophagous nematodes in forests. Isopods and diplopods were strongly structured by dispersal constraints, while springtails exhibited weaker environmental responses, likely due to their higher dispersal capacity. Additionally, sexual size dimorphism in Carabidae varied by habitat, with female-biased dimorphism in closed habitats but no dimorphism in open environments, highlighting habitat stability's role in shaping morphological traits. This study demonstrates the value of multi-taxon, multi-trophic biodiversity assessments in long-term soil monitoring. RMQS-Biodiversity provides a robust framework for soil biodiversity monitoring and conservation, refining bioindicators of soil quality and informing policies such as the EU Soil Monitoring Law
Plastic pollution in Leeward, Moorea and Cook islands (South Pacific): A baseline study
No full textInternational audiencePlastic pollution is increasingly affecting the South Pacific, including remote islands and coastal regions of Small Island Developing States (SIDS), yet data remain sparse in many areas. This baseline study presents original data on beach macrolitter and microplastics in surface waters and sediments across six islands of French Polynesia (Moorea, Bora Bora, Tahaa) and the Cook Islands (Aitutaki, Rarotonga), collected during a cruise in 2024. Beach surveys revealed high plastic contamination on most sites, with macroplastics (size >2.5 cm) densities ranging from 18 to 58 items/100 m, exceeding European threshold values (e.g. 22 items/100 m) on majority of sampled beaches. Single-use plastics and plastic fragments dominated litter, with local sources such as tourism and coastal activities clearly identifiable. Surface microplastics (315 μm–5 mm) were found at low densities, ranging from 0 to 4668 particles/km2, confirming relatively low contamination in surface waters. Only 17 particles were detected from 8 manta net tows. Sediment and beach microplastic analysis yielded very limited results, with microplastics found at only two sites (Huahine and Rarotonga), dominated by fragments and colored fibers. These results suggest localized contamination linked to urbanization and tourism rather than widespread oceanic inputs. Despite methodological limitations due to the cruise format, this study contributes rare data from undersampled regions, supporting long-term monitoring efforts and informing future policy and mitigation actions. The results underline the need to improve regional waste management, which will be beneficial for local societies largely based on touris