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Multiple asynchronous drought facets drive Mediterranean natural and cultivated ecosystems
No full textInternational audienceDrought is a keystone constraint with far-reaching implications for agroenvironmental threats. Yet, drought indices are mostly hydro-meteorological or agricultural, obscuring evidence of the key role agro-ecosystem diversity plays in buffering the consequences of regional climatic variability. We then question how contrasted drought facets could differentially drive the functioning of agro-ecosystems, and whether the interannual asynchrony of these facets might prevent multi-crisis events. Here, we examine how a multifaceted characterization of yearly drought events differentially relates to key agro-environmental sectors and test how these drought facets synchronize over Lebanon, a Middle Eastern drought-prone country grappling with socio-economic and political crises. Using parsimonious multiple linear regression (MLR) models, we captured the combined functional roles of six yearly drought facets (duration, onset, offset, drying rate, peak drought day, and mean intensity of episodic rainfall pulses) on major agro-environmental sectors, including winter wheat yield, tree-ring radial growth, and area burned by wildfires. Delayed drought offset and faster spring soil moisture drying rates appeared more closely associated to increased burned areas (R 2 = 0.25), while drought onset and autumn rainfall pulses from the previous year were negatively linked to winter wheat yield (R 2 = 0.12), and tree radial growth switched from a control by drought onset and to duration with increasing altitude (R 2 = 0.33). The observed asynchrony in agro-environmental response to climate variability over the 1960-2020 period appears to buffer the occurrence of concomitant extremes, a pattern that we could relate to the asynchrony in their controlling drought facets. By demonstrating the functional role of each drought facet, we conclude on the efficiency of a compound functionally-sound drought facets index for synchronous agro-environmental climate crisis warning
The politics of the menu. Dynamics of participation around agroecology in contemporary China
No full textInternational audienceBased on the experience of a family farm in southwestern China, this article analyzes the forms of politicization related to the emergence of healthy food supply chains. By analyzing the role of farmers within an association that sells peasant food, this study shows how territorialized practices influence the demand for short food chains. The Association promotes social and environmental activity through the co-construction of a food system by the actors concerned, from production to consumption. It thus opposes the conventionalization of short supply chains promoted by educated elites for affluent consumers. The article examines what remains essentially political in the commercial interaction of short supply chains, despite an authoritarian context that restricts spaces for deliberation and capitalist transformations at the expense of village economies. The article is based on ethnographic fieldwork and participatory research in Guangxi with producers, market intermediaries, researchers, and NGO members. It develops the hypothesis that the collective activity built into the market interactions of short supply chains allows for the maintenance of a space for politicization and localized action, which is gradually being restricted by the demand for healthy food and the digitization of trade
Variation in albumin glycation rates in birds suggests resistance to relative hyperglycaemia rather than conformity to the pace of life syndrome hypothesis
No full textVersion of Record, May 19, 2025 : https://doi.org/10.7554/eLife.103205.4International audienceThe pace of life syndrome hypothesis (POLS) suggests that organisms’ life history, physiological and behavioural traits should co-evolve. In this framework, how glycaemia (i.e., blood glucose levels) and its reaction with proteins and other compounds (i.e. glycation) covary with life history traits remain relatively under-investigated, despite the well documented consequences of glucose and glycation on ageing, and therefore potentially on life history evolution. Birds are particularly relevant in this context given that they have the highest blood glucose levels within vertebrates and still higher mass-adjusted longevity when compared to organisms with similar physiology as mammals. We thus performed a comparative analysis on glucose and albumin glycation rates of 88 bird species from 22 orders, in relation to life history traits (body mass, clutch mass, maximum lifespan and developmental time) and diet. Glucose levels correlated positively with albumin glycation rates in a non-linear fashion, suggesting resistance to glycation in species with higher glucose levels. Plasma glucose levels decreased with increasing body mass but, contrary to what is predicted to the POLS hypothesis, glucose levels increased with maximum lifespan before reaching a plateau. Finally, terrestrial carnivores showed higher albumin glycation compared to omnivores despite not showing higher glucose, which we discuss may be related to additional factors as differential antioxidant levels or dietary composition in terms of fibres or polyunsaturated fatty acids. These results increase our knowledge about the diversity of glycaemia and glycation patterns across birds, pointing towards the existence of glycation resistance mechanisms within comparatively high glycaemic birds
OntoPFAS : Ontologie des PFAS et de leur exposition
No full textMISTEA - Axe informatiqueInternational audienceLa construction d'ontologies est une des premières tâches dans le domaine de la représentation des connaissances. Elle reste très pertinente aujourd'hui, grâce à l'expressivité des langages formels, qui permettent encore d'explorer et de découvrir des connaissances. Pendant des décennies, la communauté a développé des méthodologies pour la construction manuelle d'ontologies, et plusieurs classifications de celles-ci ont été proposées. Dans cet article, nous présentons une méthodologie de construction d'ontologie basée sur des méthodes existantes, et nous l'appliquons à la représentation du domaine des PFAS (Per-et poly-fluoroalkyle substances) et de leur exposition. Les PFAS sont des substances dont la structure chimique particulière les rend très résistantes et efficaces dans de nombreuses applications industrielles. Ils suscitent un intérêt croissant en raison de leur impact négatif sur la santé et l'environnement. Ce travail s'inscrit dans le cadre du projet interdisciplinaire DAE (Détection d'Anomalies Environnementales)
Temporal dynamics and climatic indices related to long-term historical annual pressures of key grapevine diseases: case study of Black Rot and Downy Mildew in Bordeaux vineyards
No full textInternational audienceBased on a textual analysis of agricultural warning service reports and bulletins from 1941 onwards, we designed a new integrative semi-quantitative score for characterizing the annual disease occurrence and overall damage in French winegrowing regions (Fermaud et al, 2024, IOBC-WPRS Bulletin 171). In the Bordeaux region, our aim was to reconstruct, analyze and compare the grapevine past exposure to two major harmful diseases, i.e. Black rot “BR” (Guignardia bidwellii) and downy mildew “DM” (Plasmopara viticola). For the first one, we designed original overall annual climatic indices, calculated specifically, for testing that the BR pathological scores over a long-term period may be explainable - at least partly - by specific seasonal weather features. For the latter, in the past 84 years, the historical time distribution data were finely analyzed on a per-decade basis (decennial-risk period). As a clear and marked trend, we found that Bordeaux vineyards were exposed to an increasing pattern of the DM overall-intensity. Lastly, occurrence of potential inter-relationships have also been tested between the time-series distributions of the two pathogens.By reconstructing the disease annual occurrences and overall severities that affected grapevines over time, we will able to discuss more in deep the epidemiological status of the different past vintages and analyze long-term trends versus more isolated pathological phenomena. As a current prospect, in addition to the development of bio-climatic indices for the different diseases - other than BR presented here - the improved knowledge of the decennial-risk levels is of prime importance from an insurance point of view for contributing to a decrease in pesticide use (UMT-SEVEN project under way). Finally, a collaboration is also in progress with historian scientists of Montaigne Univ. Bordeaux, in order to gain a better understanding of how diseases expressed over a long-term period in relation to the socio-economic and technical contexts (e.g. advances in viticultural and/or phytosanitary techniques…)
Décrire la parcelle et étudier l'arbre en forêt Le Fil Rouge, un projet pédagogique interdisciplinaire au master
No full textInternational audienceOuvert en 2021, le master Sciences du Bois aborde le bois depuis sa fabrication dans l'arbre jusque dans ses usages,matériaux ou molécules. Il est construit autour de 3 piliers : le choix de pédagogies actives, l'interdisciplinarité et lesouhait de construire des ponts entre la recherche académique et les entreprises de la filière forêt-bois
A roadmap for the adoption of pangenomics in agronomy
No full textPangenomics is transforming the way genomics is done. By using assemblies of multiple complete genomes for the same species, it is possible to depart from a biased, reference-centric, point of view. Represented as graphs, these pangenomes open new paths for genome understanding and improvement of species of agricultural interest. However, transitioning to a graph-based approach is not straightforward, and many tools are still needed for this shift. While numerous papers present both methodological and applied approaches on pangenomics, and many reviews present advantages of these methods, very few resources outline what remains to be done. In this paper, we would like to list methods that are still required to fully exploit pangenomes, and favor the widespread adoption of this approach
Brettanomyces bruxellensis Strains Display Variable Resistance to Cycloheximide: Consequences on the Monitoring of Wine
No full textInternational audienceBrettanomyces bruxellensis is a yeast that causes spoilage in red wines due to its ability to produce volatile phenols, compounds associated with major sensory defects. Specific monitoring of low populations of this species in complex ecosystems such as wine during fermentation or aging often relies on plating onto selective media supplemented with cycloheximide. However, the variability of B. bruxellensis sensitivity to this antibiotic needs to be better characterized. A collection of 175 B. bruxellensis strains was, thus, grown on YPD medium supplemented with increasing concentrations of cycloheximide (0 to 0.5 g.L -1 ), and yeast development was monitored for 20 days by image analysis. This study revealed significant inter-strain variability, with some strains showing very late or even no growth at high cycloheximide concentrations. The cycloheximide inhibitory effect was also doseand population-dependent. In addition, colony size was frequently reduced at high doses. Additional tests were conducted on a subset of strains grown in wines with either low pH or high alcohol content or containing sulfur dioxide and then plated in the presence of increasing concentrations of cycloheximide. This revealed a cumulative effect of wine and cycloheximide stresses that resulted in an even higher delay in yeast detection. The results confirm the huge phenotypic diversity of the species and highlight the need to adapt the plates' incubation time, particularly when the selectivity and the doses of cycloheximide needed are high (samples taken in pre-fermentation phases or during fermentation) or in case of stressful wine analysis, to minimize the risk of false negatives.</div
Integrating genetic and ecophysiology frameworks for crop adaptation
No full textInternational audienceGenetic diversity, environmental plasticity, and the evolution of crops by plant breeding are three pillars to crop adaptation. A convergence between these domains began to take shape at the turn of the 21 st century, when the genetic dissection of quantitative traits was combined with ecophysiological modeling, offering biologically-grounded representations for the multiscalar formation of phenotypic variation. Over the past quarter century, multiple approaches to this integration have developed around an expanding research capacity in genomics, phenomics, and modeling. This has shed light on the astounding complexity and context-dependency of genotype-environment interactions that determine crop adaptation. Even knowing that high-level complexity can arise from simple interactions, the full scope of interactions are known not to be simple ones. Use of the genetic-ecophysiology interface for predictive modeling and explanatory analysis has provided an experimentally tractable approach to investigate this. Key insights have been gained into what lies behind decades-long genetic progress in crop yields, while exposing the potential to mitigate negative impacts of climate change or open new paths for future breeding. We expect this convergent area of research will continue to provide useful insights for biology and breeding, and serve as the foundation for navigating complexity and modeling crop adaptation in the digital age.</div