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Self production of bioinputs or biofactories: A taste of future for smallholders?
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/614899/)International audienceThe aim of a biofactory is to empower the local development of agriculture. To get an overview of such infrastructures, a non-exhaustive inventory has been drawn up in Latin America, sub-Saharan Africa, and Asia, using literature, websites, and contacts. They vary widely in size, from individual production of bioinputs to village communities trained by Paysans Relais (in Madagascar), University structure, and crop-protection firm-type entities. The bioinputs produced, given or marketed to smallholders, are mainly organic fertilizers (compost-based biofertilizers such as 'Bokashi'), substitutes for synthetic pesticides such as plant-based preparations, and microbial solutions (e.g., biostimulants). Beneficiaries often practice organic or agroecological farming. To help set up a biofactory, guides and videos are available. Diverse factors influence the adoption or rejection of the produced bioinputs. Among the constraints to be overcome before a biofactory can be truly deployed are the availability of technical and plant materials, the time required to prepare and store bioinputs, their effectiveness in relation to their application frequency (for botanical extracts), and the product cost when marketed. A main important factor for their implementation is their promotion by institutions, governments (as in Colombia), and organizations (e.g., ESSOR, Ethiquable) some being non-profit. Research is called upon at every stage to validate the bioinput value chain
De l'annotation intégrale à l'analyse des réseaux de personnages : un modèle pour la REN dans les textes littéraires en français
No full textInternational audienceLes corpus textuels sont au coeur des Humanités Numériques, mais leur exploitation à grande échelle reste limitée par l'absence d'outils adaptés, notamment pour la Reconnaissance d'Entités Nommées. Pour y remédier, nous présentons un corpus de sept romans français du XIX e siècle, annotés intégralement. Cette ressource permet d'entraîner et d'évaluer des outils robustes aux spécificités littéraires. Nous proposons un modèle de REN basé sur CamemBERT, performant sur ce type de textes, et montrons son intérêt via l'extraction de réseaux de personnages, ouvrant de nouvelles perspectives sur les dynamiques narratives. Les ressources sont librement accessibles en ligne
Comprehensive annotation of olfactory and gustatory receptor genes and transposable elements revealed their evolutionary dynamics in aphids
No full textInternational audienceGene duplication and transposable elements (TEs) are major drivers of genomic innovation that can fuel adaptation. While the roles of duplication and TE-driven diversification are documented in plant pathogens, they remain insufficiently explored in insect pests such as aphids, where olfactory (OR) and gustatory receptor (GR) genes are key to host recognition. We analyzed 521 OR and 399 GR genes, alongside TEs, across 12 aphid genomes with varying host ranges. Aphid lineages with broader host ranges exhibited higher evolutionary rates, driven by gene family expansions linked to host interaction, including lipid metabolism, immune function, and transposase activity. OR and GR genes evolved through proximal and tandem duplications and were shaped by diversifying selection, with bursts of positive selection followed by prolonged purifying selection, consistent with adaptation to novel hosts. Younger TEs were significantly enriched near OR genes compared to GRs and other genomic regions, suggesting a catalytic role of TEs in their diversification. However, OR proteins encoded by TE-associated ORs exhibited reduced functional potential. In contrast, GR proteins encoded by TE-associated GRs retained signatures of adaptation, as inferred from deep learning models predicting functionally important protein regions. These findings suggest that TE activity may facilitate functional innovation in GRs while alleviating constraints or pseudogenization in ORs. This study reveals how duplication, selection, and TE dynamics shape gene evolution in insect pests. It also provides the first chromosome-scale genome assembly of Dysaphis plantaginea, with comprehensive annotations and functional predictions of OR/GR genes, bridging adaptive evolution with mechanistic insights
A Bradyrhizobium isolate from a marine diatom induces nitrogen-fixing nodules in a terrestrial legume
No full textInternational audienceBiological nitrogen fixation converts atmospheric nitrogen into ammonia, essential to the global nitrogen cycle. While cyanobacterial diazotrophs are well characterized, recent studies have revealed a broad distribution of non-cyanobacterial diazotrophs (NCDs) in marine environments, although their study is limited by poor cultivability. Here we report a previously uncharacterized Bradyrhizobium isolated from the marine diatom Phaeodactylum tricornutum. Phylogenomic analysis places the strain within photosynthetic Bradyrhizobium, suggesting evolutionary adaptations to marine and terrestrial niches. Average nucleotide identity supports its classification as a previously undescribed species. Remarkably, inoculation experiments showed that the isolate induced nitrogen-fixing nodules in the Aeschynomene indica legume, pointing to symbiotic capabilities across ecological boundaries. Pangenome analysis and metabolic predictions indicate that this isolate shares more features with terrestrial photosynthetic Bradyrhizobium than with marine NCDs. Overall, these findings suggest that symbiotic interactions could evolve across different ecological niches, and raise questions about the evolution of nitrogen fixation and microbe–host interactions
Cambodian rice field soils infested by Meloidogyne spp. unveil a potential source of natural pest biocontrol agents
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/615302/)International audienceRice is a key staple crop and economic resource in Cambodia. Yet national yields are below regional averages due to the prevalence of persistent biotic stressors, including the rice root-knot nematode Meloidogyne graminicola. This pathogen is highly prevalent in Cambodian rice cropping systems, where current control measures primarily rely on water management and chemical nematicide treatment approaches that are often environmentally detrimental and unsustainable. Microbial biocontrol agents could offer a promising alternative for long-term nematode suppression. This study focused on soils from 13 rice fields in three Cambodian provinces to assess their suppressiveness against M. graminicola. An in vitro bioassay assessing second-stage juvenile (J2) mobility responses to soil suspensions revealed 30–95 % antagonistic activity. Nematofaunal communities were characterized alongside microbial community profiled using 16S and 18S metabarcoding. Threshold Indicator Taxa ANalysis (TITAN) was conducted to identify taxa associated with suppressive activity. Suppressive soils were found to be enriched with 105 bacterial and fungal taxa overall, along with several site-specific indicator taxa associated with localized antagonistic activity. These included known nematode antagonist taxa such as Saccharopolyspora, Kitasatospora, Lysinibacillus and Mortierella, as well as potential keystone taxa like Ohtaekwangia. Several previously unreported taxa were also associated with nematode inhibition. These findings revealed diverse microbial candidates with potential biocontrol activity against M. graminicola, thereby offering a stepping stone for the development of sustainable microbe-based rice nematode management strategies
Tomato yellow leaf curl Reunion virus: A novel tomato-infecting monopartite begomovirus from Reunion Island
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/615294/) * Autres projets (id;sigle;titre): ;;(REU) Dispositif de partenariat en santé et biodiversité//International audienceThis is the first description of the complete genome sequence of a new monopartite begomovirus isolated from tomato leaves with symptoms of tomato (yellow) leaf curl disease collected on Reunion Island, for which we propose the name "tomato yellow leaf curl Reunion virus" (TYLCREV). Phylogenetic analysis showed that TYLCREV belongs to the Old World monopartite begomoviruses and is most closely related to tomato yellow leaf curl virus (TYLCV). The genome of TYLCREV displays evidence of interspecies recombination and is composed of a portion (52%) that is closely related to TYLCV (>97.6% sequence identity) and a portion (48%) that is closely related to begomoviruses that have been found in tomato plants in Madagascar (> 91.6% sequence identity). The discovery of TYLCREV in diseased tomato plants in Reunion calls for epidemiological surveillance and further investigations to assess the prevalence and risks associated to this new virus in Reunion and beyond
Multidimensional plasticity of phenology: assessing the effects of population density on plastic responses of breeding time to temperature
No full textInternational audiencePhenotypic plasticity is the key adaptive mechanism behind annual adjustment of breeding time in response to temperature. In nature, organisms are not only subjected to variation in temperature but encounter multiple fluctuating environmental factors that affect phenotypic expression, including conspecific density, which affects individual performances through resource competition. We examined the interactive effects of temperature and conspecific density at two spatial scales (territory and patch level) on breeding time and success utilizing data obtained from long‐term monitoring of a wild great tit Parus major population in a fragmented woodland. As expected, we detected earlier breeding in response to warmer spring temperatures. We report earlier laying at low territory level density (i.e. a larger available area per breeding pair), but no evidence of density effects at patch level (breeding pairs per hectare). Birds experiencing low territory level density throughout their life bred on average earlier, and this response was also seen at the within‐individual level (earlier laying in years when individuals experienced a lower density than average). We found no context‐dependence of plastic responses to warmer springs as we detected no interactive effects between density and temperature. In terms of breeding success, earlier laying decreased the risk of brood failure and increased the number of fledglings. The number of fledglings was higher at low territory level density, while higher patch level density increased the probability of brood failure. Altogether, these results indicate that density‐related responses were likely mediated by food competition rather than by increased numbers of low‐quality birds or increased occupation of poorer territories at higher densities. This study highlights the importance of examining parameters at different spatial scales, along with the study of individual responses to multivariate cues for a comprehensive understanding of the variations in phenological plasticity
Co-translational mRNA decay in plants: recent advances and future directions
No full textInternational audienceTight regulation of mRNA stability is essential to ensure accurate gene expression in response to developmental and environmental cues. mRNA stability is controlled by mRNA decay pathways, which have traditionally been proposed to occur independently of translation. However, the recent discovery of a pathway for co-translational mRNA decay (also known as CTRD) reveals that mRNA translation and decay can be coupled. While being translated, an mRNA can be targeted for degradation. This pathway was first described in yeast and rapidly identified in several plant species. This review explores recent advances in our understanding of CTRD in plants, emphasizing its regulation and its importance for development and stress response. The different metrics used to assess CTRD activity are also presented. Furthermore, this review outlines future directions to explore the importance of mRNA decay in maintaining mRNA homeostasis in plants
Déploiement de réseaux denses de suivi de la pression lumineuse pour des actions territoriales: les cas de l'île de La Réunion et de la Brière, France
No full textInternational audienceDense networks of photometric sensors offer high-frequency, high-resolution data at unprecedented spatial scales. Such arrays detect lighting variations across minutes to years, enabling both short- and long-term assessments, while also enhancing skyglow and radiative transfer modeling. Critically, they support fine-scale evaluation of lighting policies — such as LED transitions or dimming regulations — by tracking their effects on sky brightness. These systems also enable near-continuous monitoring of Artificial Light At Night (ALAN) changes with atmospheric conditions including aerosols and cloud cover, and help validate satellite-derived products while informing ecological and health impact assessments. In this contribution, we present high-resolution datasets from two dense TESS-W sensor networks deployed for long-term ALAN monitoring in: (1) Réunion Island, a French territory in the Indian Ocean with volcanic terrain, high biodiversity, and a rapidly urbanizing coast; and (2) the Brière region, a wetland near France’s Atlantic coast, home to a regional nature park and sensitive nocturnal ecosystems. These networks provide continuous, multi-year measurements of night-sky brightness at fine spatial (~km) and temporal (~minute) scales. We describe the network architecture, calibration procedures, data processing pipeline, and access details. By making these high-resolution ALAN datasets openly available, this work enhances our ability to monitor light pollution and evaluate the effectiveness of mitigation strategies. Designed as part of the Observatoire de l’Environnement Nocturne of the French National Centre for Scientific Research (CNRS), these datasets offer a robust empirical foundation for investigating the multifaceted dynamics of light pollution across ecological, atmospheric, sociocultural, and territorial contexts. They also contribute to publicengagement and educational initiatives, fostering broader awareness and collective action toward preserving the nocturnal environment
The ANTARES detector: two decades of neutrino searches in the Mediterranean Sea
No full textInternational audienceInterest for studying cosmic neutrinos using deep-sea detectors has increase after the discovery of a diffuse flux of cosmic neutrinos by the IceCube collaboration and the possibility of wider multi-messenger studies with the observations of gravitational waves. The ANTARES detector was the first neutrino telescope in seawater, operating successfully in the Mediterranean Sea for more than a decade and a half. All challenges related to the operation in the deep sea were accurately addressed by the collaboration. Deployment and connection operations became smoother over time; data taking and constant re-calibration of the detector due to the variable environmental conditions were fully automated. A wealth of results on the subject of astroparticle physics, particle physics and multi-messenger astronomy have been obtained, despite the relative modest size of the detector, paving the way to a new generation of larger undersea detectors. This review summarizes the efforts by the ANTARES collaboration that made the possibility to operate neutrino telescopes in seawater a reality and the results obtained in this endeavor