French Agricultural Research Centre for International Development

The resistance and resilience of soil microbial communities to an environmental disturbance are poorly documented, due to the lack on onfield diachronic experiments, limiting our ability to design adapted agroecological practices. This is especially true in rubber plantations, one of the most planted tree in tropical areas. We aimed to understand (1) how soil disturbances occurring during the rubber replanting phase affect the soil microbiome, (2) how agricultural practices combining legumes cover crops and tree logging residues shape community resilience and (3) how microbial responses vary across different edaphic contexts. In two plantations with distinct soil properties in Ivory Coast, soil microbial communities were surveyed every 6 months for 24 months after soil perturbation. Community structure, functioning and networks were described based on a 16S/18S rRNA gene investigation. Prokaryotes were generally more resistant to soil perturbation than microeukaryote communities. Prokaryotic resilience dynamics were faster than those of microeukaryotes, the latter being deeply modulated by cover treatments. These specific dynamics were exacerbated in the sandy site. Co-occurrence network modelling provided useful insights into microbial resilience trajectories. We argue that this tool should be more widely used to describe microbial community dynamics. Practices involving a combination of logging residues and legume cover crops have shown beneficial effects on the community resilience in the sandy site and appears as promising agroecological practices. However, the major influence of soil texture warns of the need to consider pedological context when designing pertinent agroecological practices.

The Black and Nhue-Day River sub-basins near Hanoi, Vietnam, are crucial aquatic ecosystems that are suffering from severe pollution stemming from industrial, domestic, and agricultural sources, which pose risks to environmental and public health. We assessed water genotoxicity at four locations along a gradient of urbanization in Hanoi and its peripheral regions: a fish farm at Hoa Binh reservoir (HB), a peri-urban fish farm in Phu Xuyen district (PX), and urban lakes Truc Bach (TB) and Thien Quang (TQ). Using the comet assay on Nile tilapia erythrocytes, DNA damage (% tail DNA), reflecting fragmented DNA that migrates out of the nucleus during electrophoresis, demonstrated significant differences between sites (p < 0.001). Urban lakes exhibited lower damage (TB: 16 ± 10%, TQ: 33 ± 17%), while the highest damage levels were observed in the hydropower reservoir (HB: 70 ± 15%). Trace elements (i.e., As, Cd, Cr, Ni, and Pb) analyzed in water did not exhibit a significant correlation with DNA damage, suggesting the presence of other unexamined contaminants, such as pesticides, that may explain these findings. These genotoxicity results emphasize the need for further research to identify the specific origins of the observed DNA damage, such as potential contributions from agricultural runoff, untreated wastewater, or other unexamined contaminants. Understanding these sources is essential for developing targeted water management practices to mitigate environmental risks and ensure the safety of aquaculture products, particularly in areas like the HB reservoir, where fish farming supports food security.

The creation of new materials based on metal-free catalysts represents a sustainable alternative in the treatment of water contaminated with dyes. In this context, the use of agro-industrial wastes for the creation of hydrochars with applications in environmental water remediation is an attractive and green option for metal-free catalysts for visible heterogeneous photocatalysis. In this study, hydrochars derived from agro-industrial waste of Prunus persica (peach pit) and their application in visible photodegradation of dyes were performed. The evaluation of the temperature and reaction time of hydrochars showed that 180 °C and 3 h yielded the highest photocatalytic activity and lower energy requirements in their preparation. The electron paramagnetic resonance (EPR) characterization evidenced the presence of persistent free radicals of the oxygen-centered radical type and, together with the oxygenated groups present in the carbonaceous structure of the hydrochar, promoted the generation of radical species such as superoxide and hydroxyl radicals. The visible photodegradation experiments of methylene blue (MB) demonstrated a high degradation efficiency of 92.9% using the following conditions: Ci = 10 mg/L, pH 7.0, hydrochar dosage: 50 mg, V: 50 mL, 120 min of irradiation time, and white-LED irradiation source. In addition, the generation of radicals •OH, O2−•, and ¹O2, was demonstrated, as well as the potential use of the hydrochars for photodegradation in tap water and effluent of wastewater treatment plant matrices. Finally, the valorization of Prunus persica biomass through hydrochar production offers a promising avenue for water treatment and a route for the revalorization of agro-industrial waste. Graphical abstract

The expectations of digital technologies in sustainable agricultural development are considerable. However, applying these technologies in agri-food value chains can have downsides, which are still barely studied. The main objectives of this systematic literature review were to discover the state of the art of the research in the use of digital technologies in business models contributing to sustainability in the agri-food sector, and to make recommendations for future research and management practice. In order to bring concepts together and develop a theoretical framework and advance knowledge, performing a literature review is conducive. Here, the commonly-used PRISMA-method was used to develop a systematic literature review. From this review, an overview of business model innovations, and drivers, benefits and drawbacks of digitalisation in agri-food value chains were distinguished. Key themes found in the literature were the effects of COVID-19 on digitalisation and business resilience, the economic sustainability of business models, and the importance of communication technologies in agri-food value chains. This article recommends for future research and management practice to use a framework that looks through a value co-creation and open innovation perspective to the individual business model level and the interaction between (sustainable) business models in local and global food systems.

Sequence Demarcation Tool (SDT) is a free user-friendly computer program that has been adopted by many geminivirologists as a means of robustly and reproducibly using pairwise genetic identity calculations to classify geminivirus whole genome sequences. As input SDT takes unaligned sequences and it outputs publication quality pairwise identity plots and color-coded distance matrices. Whereas the distance plots are useful for guiding the establishment of strain, species or genus demarcation thresholds that will yield minimal classification conflicts, the distance matrices aid the classification of sequences according to the taxonomic demarcation criteria of the International Committee on Taxonomy of Viruses. Accordingly, over the past 10 years, SDT has been extensively used for the establishment of new genera in the family Geminiviridae and for the classification of hundreds of new species within individual geminivirus genera.

Despite a growing literature highlighting the benefits of agroecology in Africa, policy makers, donors, and scientists are still debating the “viability” of agroecological practices. However, assessing the viability of agroecological practices poses challenges, and so far, no studies have clearly documented them and options for addressing them. The aim of this paper is to describe the main methodological challenges we faced in assessing the viability of agroecology in 11 case studies in Africa so that others planning assessments can benefit from what we learned. Seven methodological challenges discussed are (i) defining an object of study through a list of practices or agroecological principles, (ii) having a practice-based assessment versus a systemic assessment at field or farm scales, (iii) having a subjective assessment of the viability of agroecological practices based on farmers’ perspective or an “objective” assessment, (iv) having a qualitative or quantitative assessment, (v) having a diachronic versus synchronic assessment, (vi) having a multisite approach versus a single-site study, and (vii) having a context-specific assessment method or a unitary assessment method. We conclude that the assessment of the viability of agroecological practices needs to be multicriteria, systemic, and based on farmers’ perspectives and not practice-based using a single simple metric. This is a change from the conventional way such systems are evaluated based on quantitative metrics. We recommend using a mixture of quantitative and qualitative assessments that highlight farmers’ perceptions of practices embedded into their farming systems, using transversal and context-specific data.

Wood density is a critical control on tree biomass, so poor understanding of its spatial variation can lead to large and systematic errors in forest biomass estimates and carbon maps. The need to understand how and why wood density varies is especially critical in tropical America where forests have exceptional species diversity and spatial turnover in composition. As tree identity and forest composition are challenging to estimate remotely, ground surveys are essential to know the wood density of trees, whether measured directly or inferred from their identity. Here, we assemble an extensive dataset of variation in wood density across the most forested and tree-diverse continent, examine how it relates to spatial and environmental variables, and use these relationships to predict spatial variation in wood density over tropical and sub-tropical South America. Our analysis refines previously identified east-west Amazon gradients in wood density, improves them by revealing fine-scale variation, and extends predictions into Andean, dry, and Atlantic forests. The results halve biomass prediction errors compared to a naïve scenario with no knowledge of spatial variation in wood density. Our findings will help improve remote sensing-based estimates of aboveground biomass carbon stocks across tropical South America.

Key message We developed a set of GATEWAY vectors to accelerate gene function analysis in soybean composite plants to rapidly screen transgenic roots and investigate subcellular localization, protein–protein interactions, and root-pathogen interactions. Abstract The generation of transgenic plants is essential for plant biology research to investigate plant physiology, pathogen interactions, and gene function. However, producing stable transgenic plants for plants such as soybean is a laborious and time-consuming process, which can impede research progress. Composite plants consisting of wild-type shoots and transgenic roots are an alternative method for generating transgenic plant tissues that can facilitate functional analysis of genes-of-interest involved in root development or root-microbe interactions. In this report, we introduce a novel set of GATEWAY-compatible vectors that enable a wide range of molecular biology uses in roots of soybean composite plants. These vectors incorporate in-frame epitope fusions of green fluorescent protein, 3x-HA, or miniTurbo-ID, which can be easily fused to a gene-of-interest using the GATEWAY cloning system. Moreover, these vectors allow for the identification of transgenic roots using either mCherry fluorescence or the RUBY marker. We demonstrate the functionality of these vectors by expressing subcellular markers in soybean, providing evidence of their effectiveness in generating protein fusions in composite soybean plants. Furthermore, we show how these vectors can be used for gene function analysis by expressing the bacterial effector, AvrPphB in composite roots, enabling the identification of soybean targets via immunoprecipitation followed by mass spectrometry. Additionally, we demonstrate the successful expression of stable miniTurbo-ID fusion proteins in composite roots. Overall, this new set of vectors is a powerful tool that can be used to assess subcellular localization and perform gene function analyses in soybean roots without the need to generate stable transgenic plants.

Understanding the capacity of forests to adapt to climate change is of pivotal importance for conservation science, yet this is still widely unknown. This knowledge gap is particularly acute in high-biodiversity tropical forests. Here, we examined how tropical forests of the Americas have shifted community trait composition in recent decades as a response to changes in climate. Based on historical trait-climate relationships, we found that, overall, the studied functional traits show shifts of less than 8% of what would be expected given the observed changes in climate. However, the recruit assemblage shows shifts of 21% relative to climate change expectation. The most diverse forests on Earth are changing in functional trait composition but at a rate that is fundamentally insufficient to track climate change.

In tropical regions, subject to significant fluctuations in feedstuffs, the body condition score (BCS) is a relevant indicator for monitoring body reserves status of farm animals. However, the most used BCS grids comes from temperate conditions and still not adapted for tropical species, which limits adoption and usefulness. The current work presents for the first time an original, low-cost, standardized BCS assessment system, suited to a large spectrum of tropical farm animals (zebu and/or crossbred cattle, buffaloes, camel, sheep, goats, horses and donkeys). Based on a rigorous set of uniform criteria for practical, easy-to-use on field conditions, the animal model used to calibrate and validate each grid is the adult female (except the male for horses and donkeys). A six-point BCS grid system is proposed (i.e., from very emaciated -0- to overweighed -5- body conditions), based on visual interpretation of the back and right-lateral sides of each animal. The overall BCS assessment criteria is built on three major anatomical regions (hindquarters; thorax and abdomen; shoulder and neck), and ten related anatomical landmarks, which provide a unique consensual global interpretation of the back and right views. On-field tests of the proposed BCS grids for each animal species revealed acceptable reproducibility with regard to the most conventional, established gold-standards BCS methods (r² = 0.67–0.99). The proposed harmonized BCS is relatively simple and must facilitate the adoption of regular, accurate BCS assessment by adequately trained operators linked to tropical animal production environments.

Understanding the carbon sequestration potential of undisturbed and rehabilitated mangrove ecosystems is crucial for mitigating the effects of climate change. In this study, the above-ground biomass (AGB) and structural complexity of natural, rehabilitated and regenerated mangrove forest stands were investigated. Using 32 years of Landsat time series-based normalized difference infrared index data and transect field inventory methods, we examined species and structural diversity as well as AGB distribution across 24 plots spanning a gradient from sea to land. A common allometric model and linear regression analysis were used to evaluate the influence of species diversity, structural complexity, and tree density on AGB. The results revealed that natural mangrove stands exhibited higher AGB, structural complexity, and species diversity than the rehabilitated and regenerated stands. The Shannon diversity index had a negligible effect on AGB, whereas structural complexity significantly influenced AGB in natural stands. This may be attributed to the predominance of rehabilitated monoculture and less diverse scrub mangroves in natural stands. Total AGB ranged from 45.05 to 536.48 tons/ha in natural stands and from 61.57 to 98.99 tons/ha in rehabilitated stands. Our findings illustrate the challenges (e.g., high-density plantation practices, lack of species diversity, and unsuitable site conditions for planted species) associated with current rehabilitation efforts and provide insights for optimizing future rehabilitation strategies.

School food environments play an important role in shaping children's food‐related decisions, including where and what foods to acquire and consume on a school day. In Ghana, evidence indicates that food environments in and around schools may limit healthy food acquisition and consumption behaviour. This study aimed to understand how children's experiences and perceptions of their school food environment influence food acquisition and consumption decisions. Data from 18 focus group discussions with children (n = 157; aged 10–17 years) attending Public Basic Schools in the Greater Accra Region of Ghana were analysed, guided by the African urban food environment framework for creating healthy nutrition policies and interventions. Children's food decisions in school were found to be influenced by experiences and perceptions at multiple food environment levels: macro, physical and social levels in combination with individual‐level factors. At the macro level, exposure to food advertisements on television emerged as an influence on food‐related decisions. At the physical level, experiences and perceptions of environmental sanitation, food vendor hygiene practices, affordability, and food quality were consistently reported to influence decisions. Social‐level experiences including influence from friends/peers, family (mostly caregivers/parents) and social qualities of food vendors also shaped food‐related decisions. Caregiver/parental dietary advice was often linked to healthier acquisition and consumption decisions by children in school. The findings highlight the need for actions that work in synergy across multiple levels of the school food environment to create conditions that support children to acquire and consume healthier diets.

Soil plays a critical role in ecosystem functioning and on the provision of ecosystem services. The soil fauna, especially earthworms, contributes to these processes through their action on the physical, chemical and biological properties of the soil. Recently, however, several regions of the world have been invaded by alien land flatworms, among which some species are predators of earthworms, but also of gastropods. In particular, Obama nungara, a flatworm originating from South America, has been abundantly introduced in Western Europe. In order to test whether and how the community of soil organisms can be maintained after O. nungara is introduced, we employed the Ecological Discrete-Event Network (EDEN) modelling framework to model all the possible trajectories that the community could take in an invaded garden. For this purpose, we focused on a reduced set of variables and formal rules describing the trophic chain exposed to O. nungara under two contrasting precipitation regimes. We demonstrated that the soil community is resilient to the invasion by O. nungara, since all losses of prey populations were reversible, except if the ecosystem was durably trapped in a situation of drought. Even in this case, endogeic earthworms could be maintained thanks to their limited reliance on the soil surface. We showed in this study the potential of possibilistic and qualitative models to conduct prospective studies on the impacts of invasive species on soil ecosystems, which can be more generally applied to a whole range of alien species and ecosystem types.

Background Insect bite hypersensitivity in horses (“sweet itch”) is a common pruritic, chronic, seasonal, and recurrent dermatitis affecting approximately 10% of horses in France and is a major concern for the horse industry and private owners. This dermatitis results from an allergic reaction to the saliva of specific biting flies (Diptera: Nematocera), primarily from the Culicoides genus. Given the frequent occurrence of this health problem and the limited investigation in France, we conducted a field survey in the vicinity of a riding stable in southwestern France with a reported chronic case of recurrent horse dermatitis to (i) characterize the Culicoides species associated with horse populations and (ii) estimate the relative abundance of the different species identified based on the trapping site location. Methods For this purpose, three Onderstepoort Veterinary Institute (OVI) traps were set up for one night once a week, from mid-June to the end of July 2022, the known adult peak activity period. Traps were placed either indoors or outdoors at horse facilities. Results Culicoides obsoletus/scoticus were more abundant (58.3%), followed by C. circumscriptus (12.1%), C. nubeculosus (11.5%), C. punctatus (5.6%), C. festivipennis (3.8%), C. pulicaris (2.3%), C. riethi (2.3%), C. parroti (2.2%), and the remaining species, C. lupicaris, C. dewulfi, C. brunnicans, C. flavipulicaris, and C. picturatus, collectively representing only 1.4%. Importantly, C. obsoletus/scoticus and C. circumscriptus were found indoors in notable proportions (54% and 11.4% of captures, respectively). Conclusions The findings highlight the continuous exposure of horses to Culicoides bites during the warm season, including at night and indoors, from C. obsoletus/scoticus, but also including low-impact species like C. punctatus and C. pulicaris. This underlines the need for ongoing research and surveillance. Graphical Abstract

Purpose To present the outcomes of the EGEA Conference on the state of knowledge regarding the contribution of diets rich in fruit and vegetables (FV) to human and planetary health, commonly included in the One Health concept. Methods The 9th edition of EGEA Conference (20–22 September 2023, Barcelona) provided a transversal and multidisciplinary perspective on the contribution of FV to One Health, in particular to the health of individuals, society and the planet. Nearly 150 international scientists and stakeholders discussed the current state of knowledge. These proceedings are based both on a literature review and the scientific studies presented by the speakers. Results Scientific evidence confirms the role of FV in preventing cardiovascular diseases and type 2 diabetes; more evidence is needed on the effects and mechanisms of FV in cancer prevention. FV production and consumption helps ensure territorial cohesion and provides a denser, nutrient-rich diet with less environmental impact (except water use) than other food groups, but use of synthetic pesticides in FV production remains a challenge that could be addressed with agro-ecological solutions. Various factors influence consumer choice and behaviour towards FV consumption across the lifespan, with specific periods being more conducive to change. New research is emerging on the role of FV consumption in regulating gut microbiota and on both mental and brain health; the potential role of FV production and supply in tackling biodiversity loss and climate change; and better monitoring of FV consumption. Conclusion Sufficient evidence confirms the contribution of diet rich in FV to One Health, with some emerging research on this topic. Concerted actions are required towards an increased consumption of FV and a more diversified and environmentally neutral FV production.

Tropical forest canopies are the biosphere’s most concentrated atmospheric interface for carbon, water and energy1,2. However, in most Earth System Models, the diverse and heterogeneous tropical forest biome is represented as a largely uniform ecosystem with either a singular or a small number of fixed canopy ecophysiological properties³. This situation arises, in part, from a lack of understanding about how and why the functional properties of tropical forest canopies vary geographically⁴. Here, by combining field-collected data from more than 1,800 vegetation plots and tree traits with satellite remote-sensing, terrain, climate and soil data, we predict variation across 13 morphological, structural and chemical functional traits of trees, and use this to compute and map the functional diversity of tropical forests. Our findings reveal that the tropical Americas, Africa and Asia tend to occupy different portions of the total functional trait space available across tropical forests. Tropical American forests are predicted to have 40% greater functional richness than tropical African and Asian forests. Meanwhile, African forests have the highest functional divergence—32% and 7% higher than that of tropical American and Asian forests, respectively. An uncertainty analysis highlights priority regions for further data collection, which would refine and improve these maps. Our predictions represent a ground-based and remotely enabled global analysis of how and why the functional traits of tropical forest canopies vary across space.

Ce travail visait à étudier les changements physiques, morphologiques et structurels des graines de pois chiches soumises à différents temps d’exposition aux micro-ondes. Les graines pré-hydratées ont été exposées aux ondes électromagnétiques, en supposant que les molécules d’eau (dipôles) absorbent l’énergie et changent d’état. Lorsque l’eau se vaporise, la pression interne augmente, et des pores, fissures et cavités peuvent se former. Les effets du traitement thermique ont été évalués par la caractérisation physique des graines et par des images microscopiques. Comparées aux graines pré-hydratées, les graines traitées avaient des dimensions moins importantes, un volume et une surface inférieurs, entraînant une diminution de la densité et du volume du lit granulaire. Les traitements ont rendu les graines plus fragiles que les graines natives, réduisant leur force de rupture. Les images ont révélé une modification de la porosité, la formation de pores, fissures et cavités, ainsi qu’un détachement du tégument des cotylédons. Selon le temps d’exposition, les graines ont été séchées et torréfiées, avec un changement de couleur et de teneur en eau finale. Ainsi, ces pré-traitements des graines peuvent faciliter les étapes de décorticage, broyage ou mouture, tout en améliorant la conservation et en développant de nouveaux arômes et goûts.