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A dataset mapping the geographical distribution of past and present collective farmers’ stores in France
No full textInternational audienceCollective farmers' stores (CFS) represent in France a unique model within alternative food networks, characterized by a collective governance exclusively managed by a group of farmers. These stores saw substantial growth in the country during the 2010-2020 decade. However, the post-COVID period, affected by inflation, appears to have sparked a wave of closures. To our knowledge, no systematic tracking of CFS openings and closures has been conducted in recent years in France, nor has any related data been made available for research purposes. Our objective was to identify all stores that have recently opened or closed, in order to analyze the expansion dynamics of this unique food retail model. By cross-referencing these data with other spatial factors — such as demographic, economic, and public policy information — it becomes possible to explore research questions that shed light on the determinants influencing the establishment or disappearance of these stores across different territories. We identified collective farmers’ stores and their location throughout France using three complementary methods: analyzing local daily newspapers, gathering participatory data through an interactive map, and sharing data via established partnerships with agricultural development organizations. We aimed to associate each store with its SIRET number (French business identification number) to enrich the data with opening and closure dates, as well as relevant administrative and economic details. Our final dataset includes 543 active stores in 2024, along with 105 that have closed over the past 15 year
Thinning enhances hydraulic safety but not growth resistance to drought in Atlas cedar on the long-term
No full textInternational audienceReducing forest stand density through thinning has the potential to improve tree vigor and mitigate hydraulic risk as it reduces competition for water, thereby improving soil water availability at the tree level. However, these positive effects might be compensated over time by the growth of the remaining trees and understory, an aspect that remains understudied. We investigated the long-term effects of thinning on vegetation regrowth, growth resistance to drought and hydraulic risk in a 1968 Cedrus atlantica plantation in southeastern France where contrasting thinning intensities were applied in 1992, resulting in stand densities of 1200 (unthinned control), 800, 600 and 400 trees.ha-1. Field measurements were conducted in 2017, 25 years after thinning, during the most severe drought since the trial's establishment. To explore underlying mechanisms, they were complemented by a modeling test using SurEau within the cohort-based model MEDFATE. Our results show that 25 years after thinning, despite similar stand leaf area index across all thinning treatments, trees in thinned stands exhibited significantly higher growth and reduced hydraulic risk (i.e., higher water potential, wider hydraulic safety margins, lower native embolism) than in the unthinned control. Model simulations suggest that this long-term reduction of hydraulic risk by thinning may result from niche partitioning between the overstory and the understory, either spatially (due to differences in rooting depth) or temporally (due to differences in ecophysiological properties). Interestingly, growth resistance to drought did not differ significantly among thinning treatments. Our results emphasize the potential long-lasting role of thinning in reducing hydraulic risk despite vegetation regrowth. Moreover, this study shows that ecophysiological indicators provide a more accurate understanding of tree drought responses during a specific drought event than the commonly used growth-based indicators
Advancing mycorrhizal research for sustainable ecosystem and agricultural practices. Editorial
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616544/)International audienc
OsKAT1 is a short Shaker potassium channel involved in root to shoot potassium translocation and contributes to rice grain yield
No full textInternational audienceSignificance: K+ transport from root to shoot is a critical process for sustaining physiological functions in aerial organs. We report here a short inward channel OsKAT1, localized in the root stele of rice, which contributes to root–shoot K+ translocation. Functional comparison between OsKAT1 and its C-terminal extended chimera OsKAT1-C1 in both Xenopus oocytes and Arabidopsis roots demonstrates that the short channel OsKAT1 mediates more efficient K+ transport than the chimera carrying a canonical C terminus. Under field conditions, OsKAT1 activity shows significant contributions to K+ accumulation in shoots and grain yield of rice, highlighting its agronomic importance.Abstract: Shaker potassium channels play essential roles in K+ uptake and distribution in plants. Studies on Shaker channels in Arabidopsis have provided a paradigmatic framework, but the rice genome encodes an additional member, OsKAT1, whose function remained poorly defined. OsKAT1-type channels are characterized by an innately short cytosolic C terminus, forming a unique clade of monocot-specific short Shakers that is prevalent in Poaceae species. In rice, OsKAT1 is predominantly expressed in the root stele. Disruption of OsKAT1 (KO mutation) leads to a significant reduction in K+ secretion into the xylem sap delivered to the shoot. Patch-clamp experiments on root stele protoplasts of WT and KO plants indicate that OsKAT1 functions as an inward channel. Functional analyses in Xenopus oocytes reveal that despite activating at weakly negative voltages, OsKAT1 is intrinsically incapable of mediating substantial outward currents—a property attributed to its truncated C terminus. Together with outward K+ channel activity, this feature enables stelar cells to remain significantly permeable to K+ around the K+ equilibrium potential. When expressed in Arabidopsis, OsKAT1 contributes to K+ transport in the xylem sap, but only in wild-type plants that express SKOR, a Shaker channel specialized for this role. These results demonstrate that OsKAT1 constitutes apreviously unrecognized component of K+ translocation to shoots and shed light on the energization and regulation underlying this function. Moreover, OsKAT1 is shown to improve rice adaptation to environmental conditions and enhance grain yield under field conditions through its facilitating root-to- shoot ion translocation
Biodiversity of Aspergillus section Flavi species isolated along the peanut paste production chain in Côte d'Ivoire
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616500/) * Autres projets (id;sigle;titre): DCI-NSAPVD-2010-64;3CI;(EU) 3C Ivoire project//International audienceThe contamination of staple foods by mycotoxins is a significant issue in sub-Saharan Africa, particularly the presence of aflatoxins in raw peanuts and peanut-based products. This contamination has severe health and economic consequences. The main aflatoxin-producing fungi belong to Aspergillus section Flavi and are grouped in three main clades: A. flavus, A. tamarii and A. nomius, newly qualified as Flavi, Kitamyces and Nomiarum series respectively. The present study assessed the biodiversity of Aspergillus section Flavi species along the peanut paste production chain in the Korhogo region in northern Côte d'Ivoire. A polyphasic approach was used to identify 256 potentially aflatoxigenic strains isolated on AFPA medium. Experiments included (i) morphological characterization, (ii) aflatoxin production on PDA medium, (iii) molecular identification using a PCR-DGGE method and DNA sequencing, and (iv) phylogenetic analyses. Three species of A. flavus clade were isolated. The most prevalent was A. flavus, which comprised mainly aflatoxin-producing strains but also atoxigenic strains, followed by A. aflatoxiformans and A. korhogoensis. The latter two produced B and G aflatoxins at higher levels than A. flavus, which only produced B aflatoxins. A. aflatoxiformans, A. korhogoensis and aflatoxigenic A. flavus strains were mainly isolated after the stages of peanut pod drying and storage in villages, as well as after seed storage by wholesalers and retailers. However, AF production requires confirmation on most appropriate inducing media. The study also indicates that the PCR-DGGE method when combined with a multi-locus phylogenetic analysis is an effective strategy for discriminating and identifying Aspergillus section Flavi species, particularly those in the A. flavus clade
Bases génétiques et moléculaires de la résistance à la fusariose chez le vanillier. Approches RNA-Seq et QTL chez Vanilla planifolia
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616349/)International audienc
Intensive management negatively impacts field margin ecosystem service indicators at both field and landscape levels
No full textInternational audienceVegetated field margins generally increase plant biodiversity and connectivity in agricultural landscapes. They can deliver ecosystem services, such as providing food and shelter for insects, or maintaining biotic regulation. But they can also represent a risk, for example by hosting competitor plants or cultivated crop pests. In this work, we evaluated the effects of agricultural practices on indicators of three ecosystem services (providing floral resources for pollinators, reducing soil erosion and conserving plant biodiversity), and one ecosystem disservice (competing with the crop by hosting problematic weeds). We used a French nationwide‐scale monitoring network, composed of more than 450 fields of cereals, vineyards, and market gardening. Plant sampling and agricultural practices surveys were conducted from 2013 to 2018. We unambiguously found that pesticide use, at either field or municipality levels, or both, had detrimental effects on ecosystem service indicators. Herbicide use and fertilization quantity decreased floral resources, affecting both their quantity and diversity. Pesticide use was also associated with fewer nature‐value species and more problematic weeds. Margin management could also sometimes affect the service and disservice indicators. This work not only increases the knowledge on the unintentional negative impacts of agricultural practices on ecosystem service indicators, and then probably on their delivery, but also demonstrates that pesticide reduction is positively associated with proxies for ecosystem services. It also stresses the fact that these practices have to be implemented at both field and municipality levels
Biodiversity co-variation patterns in a range of soil organism taxa across highly contrasting ecosystems
No full textInternational audienceSoil biodiversity as a critical component of terrestrial ecosystems and their functioning varies across spatial scales and environmental conditions. However, it remains unclear whether and how biodiversity patterns co-vary among different soil taxa across ecosystems.In this study, we compared diversity patterns of plants, earthworms, nematodes, bacteria, and fungi, as five major groups of soil organisms, across six strongly contrasting ecosystems ranging from mountain peatland to crop fields, including within-ecosystem variation in soil moisture. We hypothesized co-variation in taxonomic richness (alpha diversity) and composition (beta diversity) of multiple groups of soil organisms across ecosystems, moisture conditions and spatial scales.In partial contrast to our initial hypothesis, co-variation in the taxonomic richness among these groups was limited, though significant positive associations were found among bacteria, fungi, and earthworms across all sites. Plant diversity showed distinct associations with soil organism diversity, particularly with earthworms and bacteria, highlighting above-belowground biodiversity linkages. Beta diversity showed substantial co-variation among all soil organism groups, reflecting a spatial coupling of their communities that was influenced by differences in soil moisture conditions. These patterns were more pronounced in near-natural and no-till agroecosystems compared to conventional agricultural systems. Our results highlight that ecosystem type shapes broad-scale taxonomic richness, while local soil moisture critically influences soil biodiversity and spatial community composition, emphasizing the multi-scale drivers of soil biodiversity.</div
2026 – Techno-politiques des vulnérabilités et production des catastrophes et crises
No full textCe numéro propose d’ouvrir un échange sur la notion de vulnérabilité, l’un des piliers de l’analyse et de la production de connaissances en SHS sur les catastrophes, avec la volonté de relayer un ensemble de débats internationaux dans l’espace francophone sur cette notion.Il compte avec les contributions d’A.J. Faas (San José State University), Chloé GARDIN, Sofia GUEVARA VIQUEZ (Université Gustave Eiffel), Pascale Metzger (IRD) et Julien Rebotier(CNRS), Romain Leclercq (IRD) et Jean-Louis Perrin (IRD), ainsi qu’un entretien avec Gregory Bankoff (University of Hull)
Potential of Chinese Cabbage and Oat as Companion Plants to Protect Sugar Beets Against the Green Peach Aphid, Myzus persicae
No full textInternational audienceIn an attempt to develop alternative protection methods for sugar beet (Beta vulgaris) crops against yellows viruses and their main vector, the green peach aphid Myzus persicae Sulzer (Aphididae, Macrosiphini), we evaluate the potential of companion plants to attract or repel this aphid species. Host selection experiments in the laboratory revealed a strong preference of M. persicae for Chinese cabbage (Brassica rapa, subsp. pekinensis) over sugar beet plants, whereas sugar beet plants were strongly preferred over oat (Avena strigosa). These effects were confirmed in field experiments where sugar beets associated with oat were significantly less infested by aphids than control sugar beets, and Chinese cabbage hosted higher numbers of aphids and reduced numbers of wingless aphids at short distance. However, infection of sugar beets by yellows viruses was only reduced early in the season in plots with oat. In the other types of plots, infection was not reduced, and viruses were present in a large proportion of the sugar beet plants independently of the companion plant associated with beet. Our study shows that in spite of Brassicaceae and oat being promising candidates for a push–pull strategy controlling green aphid populations in the field, limited reduction of virus infection on sugar beets calls for further studies on the origin of yellows virus epidemics