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Potential shortfalls of using entomopathogenic fungi for boosting the sterile insect technique to control the oriental fruit fly, Bactrocera dorsalis
No full textInternational audienceEntomovectoring relies on the dissemination of biocides by insects to control plant pests and diseases. Current research aims at coupling entomovectoring with the Sterile Insect Technique (SIT). Such boosted-SIT is a promising technique to control the Oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera, Tephritidae), an invasive pest that dooms African and Asian fruit-producers and is invading Europe. Here, we investigated empirically the potential of boosting the SIT using spores of the entomopathogenic fungus, Metarhizium anisopliae. Laboratory bioassay confirmed the transmission potential of the fungus from inoculated males to males and females, with subsequent reductions in survival and fecundity. Inoculation, like sterility, nonetheless reduced male mating success. Semi-field tests (i.e., large outdoor cages) revealed greater costs of fungal inoculation on male competitivity than observed in the laboratory. Combined with effects of inoculation on male survival, these costs led to a lower reduction in female reproduction in the presence of inoculated sterile males compared to plain sterile males. As tested here, boosting the SIT with M. anisoplae spores to control B. dorsalis could reduce its efficacy. The encouraging transmission patterns, however, suggest that technical improvements may render the boosted-SIT effective in some, if not all, ecological contexts
The Chalcidoidea bush of life: evolutionary history of a massive radiation of minute wasps
No full textRaw paired reads were uploaded as NCBI Sequence Read Archives (PRJNA884376 for AHE and PRJNA1017994 for UCEs).We dedicate this work to the memory of our dear friend and colleague John LaSalle, specialist of Eulophidae, who was an enthusiastic member of this project.International audienceChalcidoidea are mostly parasitoid wasps that include as many as 500 000 estimated species. Capturing phylogenetic signal from such a massive radiation can be daunting. Chalcidoidea is an excellent example of a hyperdiverse group that has remained recalcitrant to phylogenetic resolution. We combined 1007 exons obtained with Anchored Hybrid Enrichment with 1048 ultra-conserved elements (UCEs) for 433 taxa including all extant families, >95% of all subfamilies, and 356 genera chosen to represent the vast diversity of the superfamily. Going back and forth between the molecular results and our collective knowledge of morphology and biology, we detected bias in the analyses that was driven by the saturation of nucleotide data. Our final results are based on a concatenated analysis of the least saturated exons and UCE datasets (2054 loci, 284 106 sites). Our analyses support an expected sister relationship with Mymarommatoidea. Seven previously recognized families were not monophyletic, so support for a new classification is discussed. Natural history in some cases would appear to be more informative than morphology, as illustrated by the elucidation of a clade of plant gall associates and a clade of taxa with planidial first-instar larvae. The phylogeny suggests a transition from smaller soft-bodied wasps to larger and more heavily sclerotized wasps, with egg parasitism as potentially ancestral for the entire superfamily. Deep divergences in Chalcidoidea coincide with an increase in insect families in the fossil record, and an early shift to phytophagy corresponds with the beginning of the “Angiosperm Terrestrial Revolution”. Our dating analyses suggest a middle Jurassic origin of 174 Ma (167.3–180.5 Ma) and a crown age of 162.2 Ma (153.9–169.8 Ma) for Chalcidoidea. During the Cretaceous, Chalcidoidea may have undergone a rapid radiation in southern Gondwana with subsequent dispersals to the Northern Hemisphere. This scenario is discussed with regard to knowledge about the host taxa of chalcid wasps, their fossil record and Earth's palaeogeographic history
Achieving healthy and profitable production through collective action? The case of vegetable farmers in the French West Indies
No full textInternational audienceGiven the multiple challenges that agriculture faces, collective action is a potential pathway towards more sustainable agriculture. This article aims to contribute to the literature by assessing the extent to which collective action can meet the objective of both healthy and profitable production in the French West Indies. To do so, we call on the theory of collective action and emphasise the role of formal and informal collectives in achieving the objectives of improving income and implementing agroecological practices. We use original data collected in 2022 from 409 vegetable farmers in Martinique and Guadeloupe. We consider the interdependence between farmers’ economic and environmental objectives through a simultaneous equations model. We characterise the diversity of collectives according to their degree of formalisation and to the adequacy between the objectives pursued by these collectives and the individual objectives of their members. Our results show that the achievement of an individual objective is fostered by its adequacy with the objective set by the collective and also, to a certain extent, by the degree of formalisation of this collective. It appears that achieving individual objectives is based on sharing common objectives as well as having collective rules. More particularly, we find that producer organisations – collectives considered to be the most formal – best meet the objectives of improving income and adopting agroecological practices. However, in the French West Indies, the instability of such collectives and the organisational deficiencies of the sector call into question their real long-term impact. These findings contribute to a better understanding of farmers’ decision-making and provide relevant policy implications for supporting agricultural collectives in managing and federating producers towards achieving a more healthy and profitable production
Cosmopolitique de l'agroécologie: Enquête au nord du Minas Gerais (Brésil)
No full textInternational audienceLe Brésil est connu comme géant de l’agronégoce, mais il est aussi un pays exemplaire pour l’agroécologie qui est là-bas un mouvement social large et pluriel. A partir d’une enquête de terrain de deux ans – entre 2017 et 2019 – l’ouvrage propose une plongée dans l’agroécologie brésilienne en suivant le quotidien de trois collectifs liés au principal centre agroécologique du pays, situé au nord du Minas Gerais. Accompagnant successivement des agronomes qui promeuvent ce modèle agricole alternatif et des agriculteurs familiaux qui cherchent à le mettre en œuvre, l’auteur s’intéresse à la fois aux savoirs, aux institutions et aux représentations qui circulent entre ces groupes, en prenant en compte tous les acteurs, humains et non-humains. L’étude révèle ainsi que l’agroécologie, bien plus qu’un schéma productif, est un véritable projet politique permettant l’alliance entre des manières diverses de composer le monde
Límites hidrográficos versus límites autonómicos. Disfunciones y retos de la gestión del agua en Cataluña
No full textInternational audienc
Additions to the list of arthropods of Reunion Island
No full textSpecimens collected after 2019 have been subject to a declaration for access to genetic resources and the sharing of benefits arising from their utilization, within the framework of the Convention on Biological Diversity and the Nagoya Protocol (reference ABSCH-IRCC-FR-248772-1).This work is a synthesis of new taxa for the Reunion Island identified between 1963 and 2022 and not published to date. The collections were carried out mainly by researchers and technicians from CIRAD or FDGDON. Sampling mainly targeted at crop pests and their natural enemies. The list includes 101 taxa new for Reunion. The Hymenoptera and Hemiptera are the most represented orders
Rapport du groupe thématique « surfaces continentales » du Tosca pour le séminaire de prospective scientifique du CNES
No full textAtténuer et s’adapter au changement climatique, préserver les écosystèmes tout en garantissant lasécurité alimentaire et le bien-être de la population mondiale sont des défis majeurs qui nousimposent de mieux comprendre le fonctionnement des surfaces continentales afin de participer à lamise en place et à l’évaluation de nouvelles stratégies de gestion durable et de partage desressources.Les surfaces continentales occupent une place particulière au sein du système Terre en raison deleur grande diversité. Par rapport à l’océan ou l’atmosphère, on connaît très mal les propriétésphysiques élémentaires de ce compartiment situé entre la roche mère et l’atmosphère aussi appelé« zone critique ». Cette fine pellicule à la surface des continents est le siège d’une multitude deprocessus biogéochimiques complexes qui sont de surcroît largement influencés par l’activitéhumaine. Cette influence anthropique met à mal les approches basées uniquement sur les lois dela physique et renforce le besoin d’observations satellitaires pour mieux contraindre les modèles defonctionnement de la surface continentale. Hétérogénéité et discontinuités spatiales sont descaractéristiques fondamentales de la surface continentale qui imposent des observations trèsdiversifiées et à haute résolution spatiale (voire temporelle).Depuis 2019, notre capacité d’observation des surfaces continentales a nettement progressé grâceà l’allongement des séries de mesures de missions emblématiques (e.g. SMOS, Sentinel-1 (S1),Sentinel-2 (S2), SPOT, Landsat, MODIS, Pléiades, GRACE), la mise à disposition des donnéesde nouvelles missions (Venμs 2017, ICESat-2 et GEDI 2019, Pléiades-Néo 2021, SWOT fin 2022)et la montée en charge de la constellation Planet. La communauté scientifique française s’estactivement préparée à l’arrivée des données des futures missions BIOMASS, CO3D et FLEX en2025, et TRISHNA en 2026. L’observation de la Terre (OT) étant loin de répondre à tous les besoins,de nombreuses avancées scientifiques s’appuient sur l’intégration des données spatiales avec desdonnées in situ et des outils de modélisation de plus en plus sophistiqués. Ce triptyqueOT/modèle/donnée est maintenant renforcé par l’émergence de nouvelles sources, comme lesdonnées textuelles des médias numériques ou le crowd sourcing, et des outils issus de l’IntelligenceArtificielle (IA).Grâce à ces données et outils en plein essor, la connaissance des surfaces continentales aprogressé sur de multiples fronts de recherche en sciences de la Terre, science du vivant, sciencesdes données et sciences humaines, en partie grâce à des approches pluridisciplinairesprometteuses et à la mise en place de passerelles entre la recherche et des partenaires publics etprivés. Ce partenariat cherche encore son mode de fonctionnement malgré une attente très forte dela société et des réussites notables durant ce quinquennat
Making profit from energy transition. Political struggles and accumulation strategies in Guadeloupe
No full textInternational audienceThe electricity industry in Guadeloupe has undergone a rapid transition. In this paper we analyse how this energy transition concretely occurred and what are the implications for industrial players and their accumulation strategies? Energy transition policies are configured by political struggles involving power producers (both incumbents and challengers) to ensure their profitability. We focus specifically on financial relationships and circuits underlying the Guadeloupean electricity industry, arguing that the political (de)construction of these circuits by (public and private) actors is key to better understand the transition process and/or its path-dependence. We identify three different and successive sequences of energy transition, from 2000 to 2023, characterized by different financial circuit architectures and distributive outcomes
Agrivoltaics in France: The multi-level and uncertain regulation of an energy decarbonisation policy
No full textInternational audienceThis article examines the political dynamics of regulating decarbonised energy such as agrivoltaics and questions the intersectoral logics inherent in this energy. It examines the political dynamics of multi-level and multi-sector regulation of decarbonised energy such as agrivoltaics between the local and national levels and between the agricultural and energy sectors. It hypothesises that the political dynamics of agrivoltaics regulation are first and foremost multi-level: The national framework for agrivoltaics regulation is based on incentive instruments, in which the state attempts to develop a market to achieve its decarbonisation policy objectives via guaranteed feed-in tariffs, and also on an imprecise regulatory framework. At the same time, the regulation of agrivoltaic projects is a prerogative of the local level, paving the way for the development of diversified projects. Agrivoltaics also raises the question of the encounter between two historically well-established areas of public policy: energy decarbonisation policies and agrivoltaics. These strongly mobilise agriculture and farmers and call into question the traditional balances, institutions and sectoral divisions between the energy and agriculture sectors and their players
Un atelier collaboratif réflexif sur les narratifs en agroécologie et les postures de recherche
No full textVersion "manuscrit auteur accepté". À paraître dans Natures Sciences Sociétés (2024, 32, 4) sous licence CC-BY - En attente de la préparation de copie avant publicationInternational audienceAgroecology has multiple interpretations and goals, driven by social movements, political contexts, and scientific needs. In this paper, we analyse a reflexive workshop that explored how agroecology narratives challenge researchers in supporting its implementation. While diverse interpretations and goals enrich the field, they can also lead to conflict. Researchers must navigate the tension between social activism and evidence-based policy solutions. The study findings highlight the need for creating new researcher profiles, including facilitators in long-term partnerships, establishing clear expectations, and developing "third spaces" for collaboration. Qualitative research assessment and new epistemological approaches are crucial for sustainable science that bridges the gap between knowledge and local realities in agroecological transitions.L’agroécologie est un terme polysémique qui peut être porté par des courants parfois contradictoires. Les processus de transition agroécologique induisent des tensions entre les initiatives enracinées dans les mouvements sociaux et les processus d'institutionnalisation. Les chercheurs sont ainsi tiraillés entre deux tâches potentiellement contradictoires : (i) conseiller les décideurs politiques et (ii) soutenir les agriculteurs et les parties prenantes dans leurs trajectoires endogènes. Cet article aborde cette tension en se concentrant sur le rôle des scientifiques dans les collaborations transdisciplinaires à long terme. L'étude passe en revue un atelier transdisciplinaire de deux jours organisés par la communauté de savoirs "Terres et Sols" (CoSav Terresol) qui est portée par l'Institut national français de recherche pour le développement durable (IRD). Les 40 participants, comprenant principalement des chercheuses et chercheurs, mais aussi des agricultrices, des représentantes d’ONG et des représentants des décideurs politiques, se sont engagés dans des activités réflexives et des ateliers collaboratifs afin de partager leurs expériences et d'explorer les différents narratifs de l'agroécologie et les postures de recherche impliquées dans des transitions agroécologiques. Les résultats soulignent le besoin de compétences transversales et de facilitateurs pour aider les scientifiques à dialoguer avec les différentes parties prenantes. Cela inclut la nécessité de questionner les narratifs et de considérer les implications éthiques des partenariats à long terme dans la production de connaissances agroécologiques