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The control of pests and diseases is one of the main challenges of sustainable agriculture. Plantains, with an annual production of nearly 12 million tons, are a significant staple food crop in West and Central Africa, as well as in Central America. Cosmopolites sordidus is the major pests for plantains and is present in all production areas. This study assessed how the traits and associated agricultural practices of 12 crops, usually associated with plantains in Cameroun, affected the arthropods trophic network and C. sordidus abundance. The abundance and the diversity of arthropods in experimental plots associating plantains with each of the 12 tested crops were measured. Each associated crop was described by a unique profile of traits and agricultural practices. This 'trait' approach allowed linking the plant characteristics to the abundance of arthropods from different trophic groups. Structural equation modelling was used to analyse the interactions between associated crops traits, their associated agricultural practices and the abundance of main trophic groups. The highest abundance of C. sordidus was observed in plots with Ananas comosus and Xanthosoma sagittifolium as associated crops. These plots also had the lowest abundance of omnivores and predators. In contrast, plots with the lowest abundance of C. sordidus were those with weeds and Vigna unguiculata, where more omnivores and predators were observed. Grouping associated crops by their traits and agricultural practices allowed for drawing conclusions on a wider range than the set of plants tested. For instance, this study showed that plants from the higher strata tend to decrease ground-dwelling predators. The ideal crop traits and agricultural practices to maximize the regulation of C. sordidus should not be obtained by a single species of crop but rather by a community of associated crops.

Weeds are a major threat in tropical regions where climate conditions favor their growth and development. This is particularly true in low-input rice-based cropping systems in the Malagasy highlands, where weed management is mainly done by manual removal. Crop rotation is often promoted as an efficient way to control weed infestations, while the role of fertilization is more controversial. In this study, we compared rice monoculture to three rainfed rice-based two-year rotations: rice followed by groundnut, rice followed by sorghum-cowpea mixture, and rice followed by a velvet-bean crotalaria mixture. Each rotation was tested with two levels of fertilization (5 t DM ha−1 organic manure, sole or in combination with mineral fertilizer - 400 kg ha−1 NPK + 200 kg ha−1 urea). We assessed the effect of rotation and fertilization on weed composition, diversity, biomass and rice yield. Additionally, the farmers' perception of weed harmfulness and the relation between their assessment of weed harmfulness and rice production was tested. Our results showed that weed biomass significantly decreased rice yield but only under the low fertilization level. The rotation of rice with the velvet bean-crotalaria mixture was efficient in reducing weed biomass, modified weed community composition and allowed to achieve the highest rice yield. A significant negative relationship was found between weed community harmfulness index and weed species richness. Yet, the lowest rice yield was observed under rice monoculture despite a higher species richness over years and under high fertilization level. The lack of significant correlation between the harmfulness index and the actual rice yield is probably because our index is partly based on farmer's perception, and only on major weeds. More studies on tropical weed harmfulness are needed to support the design of ecologically intensified cropping systems.

Oasis agriculture has been a critical means of sustenance for humans in arid regions in North Africa and West Asia. The date palm (Phoenix dactylifera L.) holds immense significance as one of the most vital species in these agroecosystems. It was domesticated in the Gulf region over 6000 years ago and later spread to other regions. In the Sahara, the origins of the germplasm and the diffusion history in terms of dating and routes remain largely unknown. To explore these questions, we employed traditional and geometric morphometric methods to analyse 312 well-preserved Phoenix seeds from three Libyan sites, dating from the 1st millennium BCE to the modern period. We compared them with a large modern reference collection and Egyptian archaeological seeds from a previous study. The identification of domesticated morphotypes in the oldest site, Zinkekra, confirms that the date palm was already cultivated in the Central Sahara during the 1st millennium BCE, probably through an introduction from Egypt. The large proportion of wild morphotypes however indicates that they represent early domesticates. By comparing seeds at sites in Libya and Egypt dating from different periods, evidence was found of a decrease in unclassified seeds and wild morphotypes over time, along with a simultaneous increase in seed elongation. These results likely reflect the intensification of date palm cultivation, coinciding with the growing prevalence of human selection and vegetative propagation. Our study highlights the potential of seed morphometric analyses in uncovering the domestication and diffusion history of crops, shedding light on how humans have adapted to challenging environments.

Agroecology is highly promoted in research and development discourse as a holistic and effective response to climate change. The objective of this study is to contribute to the analysis of the existing evidence that agroecology enables climate change (CC) adaptation and mitigation in the agricultural systems of Latin America, a region known for pioneering the development of this science, praxis, and movement. We applied the PRISMA method to analyze the existing literature providing such evidence. Stakeholder interviews were used to obtain in-depth perceptions of agroecology's contributions to CC adaptation and mitigation from a wide range of actors and development practitioners based in Colombia, Ecuador, and Peru: farmers, NGO representatives, researchers, university program leaders, and public officials. From a total of 1821 initially identified articles, 62 were screened, and 24 case studies analyzed for methods and evidence provided. Twenty-six stakeholders were interviewed. Combining quantitative and qualitative assessment methods, the scientific literature shows that agroecological systems are appreciated for addressing resilience in a systemic way hence not just climate change per se. Mitigation was generally assess by quantitative approaches. Integrating stakeholders' discourse to our analysis highlighted their knowledge of underlying processes contributing to farm CC resilience, where crop and animal diversification and integration of trees into farming systems are central. Stakeholders attributed agroforestry and less use of synthetic fertilizers as important roles for mitigation. Our study highlights the pertinence of combining systematic analyses of the evidence and perceptions drawn from a plurality of stakeholders to recognize the positive contribution of agroecology to climate change adaptation and resilience. However, it also pointed to future research that further assesses the specific trade-offs and synergies between agroecological practices, mitig

Background and aims: Cover crops can efficiently increase nitrogen (N) recycling in agroecosystems. By providing a green-manure effect for the next crop, they allow reduced mineral fertilisation. We developed a decision-support tool, called MERCI, to predict N available from cover crop residues over time, from a single measurement of fresh shoot biomass. Methods: We coupled a large experimental database from France with a simulation experiment using the soil-crop model STICS. More than 25 000 measurements of 74 species of cover crops as a sole crop or bispecific mixtures were collected. Linear regression models, at the species, family or entire-database level depending on the data available, were built to predict dry biomass, N amount and C:N ratio. Dynamics of N mineralized and leaching from cover crop residues were predicted at 24 contrasting sites as a function of the biomass, carbon (C):N ratio and termination date. Results: Correlations between fresh biomass, dry biomass and N amounts in experimental data were strong (r = 0.80-0.96), and predicted N amounts in fresh shoot biomass were relatively accurate. Percentages of N mineralized and leached simulated by STICS were explained mainly by the C:N ratio, site and number of months after termination, but to different degrees. Conclusion: MERCI is an easy and robust decision-support tool for predicting N release in the field, and could thus be adopted by advisors and farmers to improve management of nutrient recycling in temperate arable cropping systems.

Sugarcane crops typically have a high fertiliser nitrogen (N) input, with low N recovery efficiencies. Nitrogen is essential to crop productivity, but excess application can have negative environmental consequences. Despite the importance of coordinating N fertiliser input with crop N requirements, certain components of the sugarcane plant are typically not considered when evaluating N nutrition. The objective of this study was to establish which sugarcane crop components should be included in these evaluations given their impact on N mass accumulation and on fertiliser N recovery efficiencies. The respective biomass, N mass, and fertiliser N recovery efficiency were evaluated for sugarcane shoots, tillers, strawfall, root, and stool components over two experimental years, for fertilised (urea) and unfertilised treatments. The root component comprised, respectively, 57–65% of the aboveground N mass of fertilised sugarcane, and 74–104% of the unfertilised sugarcane. The sugarcane N requirements and uptake were shown to be more progressive over the growth-cycle when considering the strawfall and tiller components. This study emphasises the importance of evaluating belowground biomass in sugarcane N studies, and suggests that the tiller and strawfall components should also be considered when evaluating the evolution of N mass and fertiliser N recovery efficiency.

Shade trees in agroforestry systems confer ecosystem services, such as enhanced soil fertility from diverse litter inputs, microclimate regulation via shade, and disease mitigation through trophic and abiotic interactions. With this thriving role of agroforestry in sustainable agriculture, particularly for tree crops, systematic and reliable methods to select shade trees for specific agroecosystem outcomes are crucial. Plant functional traits offer a framework to describe, select and manage shade trees. Over the last decade, shade tree leaf functional traits and whole plant traits have been assessed in agroforestry systems. Yet, we lack amalgamated information on (i) what we know about shade tree trait relationships with functions to achieve desired agroecosystem outcomes, (ii) how decades of shade tree selection by farmers impacts agroforests inter- and intraspecific trait diversity, and (iii) which shade tree traits should be considered for achieving farmer priorities. We consolidate literature on Coffea arabica (coffee) and Theobroma cacao (cocoa) agroforestry systems to summarize the role of shade tree functional traits in three key ecosystem functions: soil fertility, microclimate modification and crop productivity. We compile global and regional datasets on tree functional trait diversity to show the functional space of agroforestry tree species compared with the overall functional space observed in plants. Despite, or maybe because of, high shade tree diversity, shade tree trait characterization remains coarse and commonly measured at the community scale in the literature. Based on published trait data, we show that farmers adjust the functional composition of shade trees to increase the recycling of soil nutrients (high leaf nitrogen), the production of wood (skewing towards lower wood densities) and the production of fruits (tendency towards high seed size). Common shade trees in coffee and cocoa systems fall in the mid-range of leaf acquisitive to conserva

Our research occurred in the Andean region, one of the eight global centers of domestication of plant species grown for agriculture. The shores of Lake Titicaca (located between Peru and Bolivia), at 3800 meters above sea level, are recognized as the center of origin of quinoa (Chenopodium quinoa Willd.). In this region, complex societies have emerged, thanks to the development of water and soil management technologies. They have managed to overcome high mountain territories' extreme and variable climatic conditions. These societies have traditionally protected and preserved quinoa as food for present and future generations through their long-standing knowledge and cultivation practices. The fieldwork occurred in the context of Andean family farming, and our study analyzes nature-society dynamics with a chorematic approach and interviews with local communities. The interest of this work is the transformation of the landscape at the scale of the mountain agroecosystem to understand better the impacts of rural development policies. Chorematic modeling was applied to two periods, before and after 1970, a pivotal year in Peru for agriculture, to show how socio-spatial dynamics in the Andean environment are changing, particularly concerning the evolution of quinoa cultivation. The results show that wild quinoa relatives' distribution is strongly linked to the socio-spatial organization of the agroecosystem. Different species of wild quinoa relatives are maintained by villagers for their multiple foods, medicinal and cultural uses in natural areas, grazed areas, on edge, and also within cultivated fields. However, this management is changing under the pressure of global issues related to the international quinoa market, whose requirements imply reducing the presence of wild relatives in cultivated fields.

La faible productivité de l'agriculture en Afrique subsaharienne est due en grande partie à la dégradation de la fertilité des sols. Les agricultures familiales, pilier de la sécurité alimentaire de cette grande région, doivent relever le défi de la restauration et du maintien de la capacité productive des terres. Les pratiques endogènes des producteurs telles que les associations céréales-légumineuses, les jachères pâturées, les parcs arborés... ne permettent plus d'entretenir la fertilité sur des surfaces cultivées qui s'agrandissent, surtout lorsque les sols sont carencés. Durant quatre décennies, les décideurs et acteurs du secteur agricole ont privilégié la vulgarisation des engrais de synthèse. Mais l'utilisation des engrais minéraux demeure faible et bien en deçà de la moyenne de la consommation mondiale (15 kg/ha contre 135 kg/ha). Après avoir longuement promu l'utilisation de fumure organique, la recherche invite désormais à diversifier les sources de biomasse fertilisante via l'agroforesterie, les associations avec les légumineuses, l'agriculture de conservation. D'autres techniques de conservation de l'eau et du sol ont également été mises en avant. C'est bien la combinaison de différentes pratiques qui est à construire avec les agriculteurs pour chaque situation de production, en fonction des ressources disponibles localement, d'un apport raisonné d'engrais de synthèse et d'amendement, des savoirs paysans et scientifiques. Pour cela, il est nécessaire (i) de modifier les postures des chercheurs et des décideurs vis-à-vis des ruraux et (ii) de réviser les politiques publiques toujours focalisées sur l'usage des engrais minéraux, afin de fournir des services d'appui-conseil plus diversifiés, performants et intégrant les besoins de transitions agroécologiques indispensables aujourd'hui dans un contexte de changement climatique.

Phytophagous and beneficial arthropods were inventoried on three traditional aromatic plants, lemongrass (Cymbopogon citratus), basil (Ocimum basilicum), and chives (Allium fistulosum), cropped in separate plots in a field experiment in the Caribbean island of Martinique. The same inventory was made on tomato plots, as a culture of association. Arthropods were collected using D-vac suction and Pitfall traps. Our results showed that hemipterans and dipterans dominated in D-vac suction samples with a high abundance of hemipterans on basil and of dipterans on tomato. Pitfall trap sampling revealed a high abundance of ants (mainly of the genus Pheidole) on all four crops. Aromatic plants had a significant positive effect on the abundance of both phytophagous and beneficial arthropods, while arthropod composition varied almost not at all between plant species. The Shannon index of basil and lemongrass were the highest. Aromatic plants may be used to increase population of beneficials in horticultural crops.

CONTEXT: Over the past two decades, the Mekong region has experienced significant transformation of its agricultural sector from subsistence farming to export crops driven by the expansion of agricultural land and of irrigation, plus intensification thanks to mechanization and the use of chemical inputs. In the context of agrarian transition, maintaining “organic by default” rice farming systems that do not rely on chemical inputs, is challenging. OBJECTIVE: Based on a case study in Preah Vihear, the organic province of Cambodia, this paper examines whether organic rice certification can maintain “organic by default” practices in a context of unprecedented agricultural intensification. METHODS: Using agrarian diagnosis, we investigated the impacts of an organic rice certification scheme on the future of organic rice-based farming systems. We built a functional typology of five farming systems that co-exist in the study area to understand the roles of organic rice in each system. RESULTS AND CONCLUSIONS: From an economic perspective, organic rice is less profitable than recently introduced cash crops, e.g. cassava, cashews. The positive impact of certification of organic rice is threatened by lock-in factors, e.g. labor diversification in both farming and non-farming activities, cash flow management, the certification process, leading farmers to abandon organic rice for cash crops for export. We discuss the key role of agricultural cooperatives in the certification process of organic rice. SIGNIFICANCE: The paper questions the capacity of a certification scheme to keep up with the process of intensification that undermines the profitability of the remaining “organic by default” rice systems. Beyond the significance of the results in the study area, one of the last strongholds of traditional rice systems in Cambodia, the paper illustrates the disappearance of “organic by default” rice systems in the whole country as well as in the Mekong region.

Agroecological food system transformation remains marginal in South Africa despite numerous policies, plans and programmes favouring sustainable agriculture. Problems of weak budgets, fragmented interventions and lack of coordination reflect the power dynamics in the prevailing food system, dominated by large-scale conventional agriculture and agribusiness. The paper provides an in-depth case study of the importance of promoting agroecological transitions. Following a qualitative research methodology based on a literature review for context, preparatory discussions with local contact points, and semi-structured interviews and focus group discussions with local actors in the field, the paper describes, analyses and characterises the agroecological transitions in the Overberg District in the Western Cape. It considers the broader policy, discursive and organisational landscape of agroecology followed by an in-depth analysis of the site drawing on key informant interviews and focus group discussions. The results demonstrate that local stakeholders are positioned to better connect food and nutrition issues with human health, biodiversity, climate change, natural resource management, and local development. As a result, transformative dynamics could emerge from local projects and programmes. Several lessons and recommendations are drawn to contribute to the policy debate. These highlight the potential of multi-actor coalitions which can develop from specific agroecological initiatives and activate positive dynamics, bringing in multiple interventions of municipalities.

In Western Africa, agro-sylvo-pastoral systems are dominant and food demand is booming. To meet this demand, many farmers intensify the production with industrial inputs (mineral fertilizers, feeds, pesticides, herbicides). However, the price of these inputs is rocketing. To face this issue, some farmers reconsider crops, livestock, and tree synergies and by-product recycling to increase their production sustainably at a lower cost. The study aimed to characterize the diversity of Koumbia's farming systems and to assess farming systems' technical performance in an agroecological perspective. We surveyed 391 farms in the county of Koumbia (Burkina Faso). Considering 15 agricultural practices (4 on by-products recycling, 4 on soil protection, 4 on industrial inputs limitation, 2 on smart use of natural resources, and 1 on cropping diversification), a multivariate analysis (PCA+HAC) combined to an agroecology (Ae) scoring system (−15 to +15) based on 15 specific indicators (one/practice), we highlighted 3 agroecological farming systems clusters. These clusters are distributed along a gradient of agroecology intensity (Ae+: high degree of Ae, Ae+/−: medium degree, and Ae−: poor degree). Ae+ farms (Ae score: +3.0) group 17% of the farms, Ae+/− (Ae score: −4.5) group 58% of the farms, and Ae− (Ae score: −10.5) group 25% of the farms. Ae+ raise more livestock and recycle a higher rate of crop-livestock by-products in fodder, organic manure, and mulch. These recycling practices are facilitated by better levels of equipment for transportation and storage and soil water and crop residue conservation measures, including maintenance of the wooded park on the cultivated fields. This set of practices, which close better the agricultural system, produces a systemic effect which has a positive impact on yields and on the whole ecosystem. Our findings outline for the first time that crop-livestock synergies and by-product recycling are major factors of agroecological transition in a

Assessing the conditions and performance of agroecological transitions in different contexts is key to supporting these transitions. However, assessing agroecological transitions presents methodological challenges, including: 1) being adaptable to local conditions, 2) consideration of social interactions among stakeholders involved in transitions, 3) clarifying the concept of agroecology, 4) consideration of the temporal dynamics of the transitions to better understand barriers and levers in their development, and 5) using a participatory bottom-up approach. The objective of this research was to design a method that provided evidence on 1) the barriers and levers in the development of agroecological transitions, and 2) their performance related to four dimensions: techno-economic issues, agroecosystem health, quality of life and resilience. To design, test and adapt such a method, while also involving end-users, we adopted a co-design approach based on prototyping. The co-design approach unfolded in nine stages alternating research work and co-design with end-users. The prototype was built on the approaches of existing published methods covering the five challenges for assessing agroecological transitions. It consisted of a four chronological step assessment method. The first three steps consisted of framing the assessment, with the final step a multidimensional performance assessment, using an initial set of 73 indicators to cover the four dimensions. The prototype was then tested and adapted in the village of Sare Boubou, Senegal, which is going through an agroecological transition supported by a non-governmental organization. Changes during the testing and adaptation phase affected three steps of the prototype and allowed the initial prototype to adapt to the case study's specificities, related to its scale and context. Context-related changes particularly affected the performance assessment, with a total of 31 indicators changed. The analysis of barriers and lev

The Global Plant Health Assessment (GPHA) is a collective, volunteer-based effort to assemble expert opinions on plant health and disease impacts on ecosystem services based on published scientific evidence. The GPHA considers a range of forest, agricultural, and urban systems worldwide. These are referred to as (Ecoregion × Plant System), i.e., selected case examples involving keystone plants in given parts of the world. The GPHA focuses on infectious plant diseases and plant pathogens, but encompasses the abiotic (e.g., temperature, drought, and floods) and other biotic (e.g., animal pests and humans) factors associated with plant health. Among the 33 (Ecoregion × Plant System) considered, 18 are assessed as in fair or poor health, and 20 as in declining health. Much of the observed state of plant health and its trends are driven by a combination of forces, including climate change, species invasions, and human management. Healthy plants ensure (i) provisioning (food, fiber, and material), (ii) regulation (climate, atmosphere, water, and soils), and (iii) cultural (recreation, inspiration, and spiritual) ecosystem services. All these roles that plants play are threatened by plant diseases. Nearly none of these three ecosystem services are assessed as improving. Results indicate that the poor state of plant health in sub-Saharan Africa gravely contributes to food insecurity and environmental degradation. Results further call for the need to improve crop health to ensure food security in the most populated parts of the world, such as in South Asia, where the poorest of the poor, the landless farmers, are at the greatest risk. The overview of results generated from this work identifies directions for future research to be championed by a new generation of scientists and revived public extension services. Breakthroughs from science are needed to (i) gather more data on plant health and its consequences, (ii) identify collective actions to manage plant systems, (iii) e

Herbicides are the most applied pesticides in the world. Despite numerous laboratory studies demonstrating the toxic effect of herbicides on non-target organisms, the effect of herbicides on soil organisms in the field remains complex to understand and is still controversial. In order to understand how changes in agricultural practices aiming to reduce herbicide use could impact soil biodiversity, we studied the effect of the frequency of herbicide application on soil biodiversity in a tropical agroecosystem. Our study was conducted on banana farms in Martinique, an island with a humid tropical climate belonging to the Caribbean biodiversity hotspot. Thirteen banana plots from five different farms were selected, ranging from plots receiving no herbicides to plots receiving 4–5 applications per year. Soil macro-arthropods were sampled using pitfall traps resulting in the collection of over 6,200 individuals. Of the 100 taxa that were differentiated, 75 could be identified to species level which allowed to assign each taxon to a trophic group and when possible to classify them according to whether they were introduced or native. Macro-arthropod mean species richness was 21% lower in plots with the highest frequency of herbicide application. However, no conclusive effect of herbicides on macro-arthropod abundance was demonstrated. Mean species richness for different trophic groups also decreased with herbicide applications with decreases of 22% for predators, 17% for omnivores, 55% for herbivores, and 55% for decomposers in plots with 4–5 herbicide applications per year compared to plots with no herbicide use. Species composition of macro-arthropod communities varied significantly with herbicide applications. More specifically, we found that native species represented a higher proportion of individuals captured in plots where no herbicides were used; suggesting that agroecological practices implemented at the field level to reduce the frequency of herbicide use potenti

La macrofaune du sol joue un rôle majeur dans la provision de services écosystémiques tels que le recyclage des nutriments, le stockage du carbone et la modification de la structure physique du sol. En particulier, les invertébrés saprophages, en consommant une grande quantité de litière, modifient sa dynamique de décomposition et ainsi la remise en circulation des éléments nutritifs essentiels à la croissance des plantes. Il existe une grande diversité d'invertébrés saprophages, chacun ayant un effet spécifique sur le processus de décomposition, conduisant à des complémentarités d'usage des ressources (synergies). Il existerait ainsi une relation positive entre la diversité fonctionnelle des invertébrés du sol et le processus de décomposition. L'objectif de cette thèse est d'étudier dans quelle mesure des pratiques agroécologiques novatrices peuvent restaurer la biodiversité du sol et les processus écologiques associés. Plus particulièrement, elle s'intéressera, i) d'une part au lien entre les pratiques agricoles et la composition des communautés d'invertébrés saprophages, ii) d'autre part, à la manière dont la composition de ces communautés influence le processus de décomposition et in fine la fourniture en éléments minéraux disponibles pour la culture ?

Duru et al. (Agron Sustain Dev 35:1259-1281, 2015) highlighted a missing tool for studying and improving the performance of cropping systems in the transition to highly diversified agriculture. In response, this paper proposes a concept for designing, modeling, monitoring, and auditing desired ecosystem services, in intercropping and agroforestry systems. We have labelled this concept ESSU (Ecosystem Services functional Spatial Unit). It delimits the smallest spatial unit encompassing all the interacting species and other functional components (e.g., crops, trees, livestock, spontaneous vegetation, semi-natural habitats such as hedges, ditches, forest patches, and animals) that together provide a specified set of ecosystem services. The novel ESSU concept allows representation of an entire diversified agroecosystem by the repetition of the spatial unit that provides the same sets of targeted ecosystem services as the agroecosystem it represents. It can then be used for various activities, such as the (i) design of more efficient agroecological systems according to the targeted ecosystem services; (ii) rapid audit of farming practices for biodiversity/resilience across large tracts of farmland as part of achieving Sustainable Development Goal 2 targets of sustainable food systems; and (iii) modeling such diversified agroecosystems using a motif adapted to represent the targeted ecosystem services and the species spacing design. We demonstrate that the ESSU concept is highly flexible and applicable to a wide range of diversified agroecosystems, like arable intercropping, crop-tree intercropping, tree-tree agroforestry, and agro-pastoralism. We also show its relevance and suitability for representing temporal changes over 1 year, across several years, and over decades, indicating its generalizability and flexibility. We argue that ESSU could open new theoretical and practical research avenues for the study of diversified agroecosystems. Considered with all the knowledg

Research has demonstrated that intraspecific functional trait variation underpins plant responses to environmental variability. However, few studies have evaluated how trait variation shifts in response to plant pathogens, even though pathogens are a major driver of plant demography and diversity, and despite evidence of plants expressing distinct strategies in response to pathogen pressures. Understanding trait-pathogen relationships can provide a more realistic understanding of global patterns of functional trait variation. We examined leaf intraspecific trait variability (ITV) in response to foliar disease severity, using Coffea arabica cv. Caturra as a model species. We quantified coffee leaf rust (CLR) severity—a fungal disease prominent in coffee systems—and measured key coffee leaf functional traits under contrasting, but widespread, management conditions in an agroforestry system. We found that coffee plants express significant ITV, which is largely related to shade tree treatment and leaf position within coffee canopy strata. Yet within a single plant canopy stratum, CLR severity increased with increasing resource conserving trait values. However, coffee leaves with visible signs of disease expressed overall greater resource acquiring trait values, as compared to plants without visible signs of disease. We provide among the first evidence that leaf traits are correlated with foliar disease severity in coffee, and that functional trait relationships and syndromes shift in response to increased disease prevalence in this plant-pathogen system. In doing so, we address a vital gap in our understanding of global patterns of functional trait variation and highlight the need to further explore the potential role of pathogens within established global trait relationships and spectra.

Tea is a very important cash crop in Vietnam as it provides crucial income and employment for farmers in poor rural areas. Unfortunately, the dominance of long-term, conventional tea cultivation has caused severe soil health degradation and environmental pollution. At the same time, as tea production may provide a better net income compared with other annual crops such as rice and vegetables, farmers have been converting parts of their allocated land to cultivate tea plants. Little is known about the benefit of agroecological management as an alternative to conventional tea management practices, and thus, there is a need to understand how it can improve tea yields, quality and the livelihoods of the farmers. Conducted in Northern Vietnam from 2019 to 2022, this study examined the impacts of agroecological tea management practices on soil health indicators, tea yield and quality, and net income of tea farmers. We showed that agroecological management practices significantly enhanced soil organic matter by 0.8% and soil pH by 0.5 units on average. Conversely, conventional management based on chemical fertilizer applications, significantly increased soil total nitrogen by 0.15%–0.2%. No significant differences were observed between soil texture and other soil chemical characteristics. Soil biological parameters were also significantly higher in agroecological tea soil and root samples than in conventional tea plots. Average AMF frequency and intensity of the agroecological tea roots were 98% and 37%, respectively, compared with 73% and 15% of the conventional tea roots. Likewise, soil macrofauna and mesofauna abundance in the agroecological tea plantations was 76 individuals/m2 and 101 individuals/100 g fresh soil on average, respectively, while that of conventional tea farms were 34 and 63 individuals/100 g fresh soil, respectively. Interestingly, a comparison between the converted and nonconverted lands did not show any significant effect of the conversion on soil ph

Identifying the drivers of soil organic carbon (SOC) stock changes is of the utmost importance to contribute to global challenges like climate change, land degradation, biodiversity loss, or food security. Evaluating the impacts of land use and management practices in agriculture and forestry on SOC is still challenging. Merging datasets or making databases interoperable is a promising way, but still has several semantic challenges. So far, a comprehensive thesaurus and classification of management practices in agriculture and forestry has been lacking, especially while focusing on SOC storage. Therefore, the aim of this paper is to present a first comprehensive thesaurus for management practices driving SOC storage (DATA4C+). The DATA4C+ thesaurus contains 224 classified and defined terms related to land management practices in agriculture and forestry. It is organized as a hierarchical tree reflecting the drivers of SOC storage. It is oriented to be used by scientists in agronomy, forestry, and soil sciences with the aim of uniformizing the description of practices influencing SOC in their original research. It is accessible in Agroportal (http://agroportal.lirmm.fr/ontologies/DATA4CPLUS, last access: 24 March 2022) to enhance its findability, accessibility, interoperability, and reuse by scientists and others such as laboratories or land managers. Future uses of the DATA4C+ thesaurus will be crucial to improve and enrich it, but also to raise the quality of meta-analyses on SOC, and ultimately help policymakers to identify efficient agricultural and forest management practices to enhance SOC storage.

This study aimed to link experimental data dealing with complex agroecological systems. For sharing and linking collected data with the generic AEGIS (Agro-Ecological Global Information System) database, our work described in this data paper consists in mapping researcher variables to the AEGIS dictionary variable for different tropical crops (sugarcane, rice, sorghum or cover crops). Additionally, this data paper presents a study case based on sugarcane intercropping systems for evaluating 3 matching measures of variables.

By mapping the potential interactions between two conceptual frameworks of agroecology (HLPE 2019) and food systems (David-Benz et al. 2022), and by analysing the scientific literature focusing on the agroecology/food system interface, a wide variety of links has been identified between 13 agroecological principles and 4 sustainability dimensions of food systems. They illustrate the multidisciplinary of these subjects and the potential contribution of the agroecological transition towards more sustainable food systems. Food security, nutrition and health on the one hand, and the agroecological principles of biodiversity, co-creation of knowledge and social values on the other hand, appear to be the most treated aspects of the interface. On the contrary, other agroecological principles and sustainability dimensions of food systems need further research. These include among others the equity within food systems and the principles of land and resources governance, input reduction, recycling and economic diversification. The farm/agricultural system scale is the most covered segment of food value chains, while mid-stream segments would benefit from being further explored, just like multi-scales/multi-dimensional/multi-actors research is needed to allow deeper understanding of systems and trade-offs. The key findings of this report are expected to usefully assist and guide further research relevant to the agroecological transition towards sustainable food systems.

CONTEXT Agroecosystems' social-ecological resilience largely depends on the crop diversity generated and maintained by farmers, which provides insurance against changing environmental and socio-economic conditions. In turn, crop diversity generation, maintenance, and distribution is influenced by seed circulation networks. Thus, patterns of seed circulation can support or constrain households' access to crop diversity, affecting on-farm crop diversity. OBJECTIVE We aimed at understanding the mechanisms shaping seed circulation and farmers' access to crop diversity by: 1) assessing how crop biocultural traits influence patterns of seed circulation; 2) exploring the connections between household position in the seed circulation network and on-farm crop diversity for different crops. METHODS We conducted research in south-eastern Senegal applying crop diversity inventories and a survey to document seed acquisitions for the six local staple crops, which differ in biocultural traits. Household's varietal diversity and household- and community-level network measures calculated for each crop were used to compare seed circulation patterns among crops. Then, we analyzed the association between households' position in the seed circulation networks and households' on-farm crop diversity using generalized linear models. RESULTS AND CONCLUSIONS Our research advances two main findings about the importance of seed circulation networks for farmers' access to crop diversity. First, several seed circulation networks operate in the same community and at the same time. Each species circulated differently, which can be explained by crop's biocultural traits. Socio-cultural traits, like the cultural relevance of a crop, and biological traits, like crop's functional group (e.g., legumes, cereals), affect the patterns of seed circulation. Seed circulation networks that involved external actors, like agricultural extension projects or NGOs, were more centralized than seed circulation networ

Les formes d'agriculture se revendiquant de l'agroécologie (agriculture biologique, agriculture de conservation des sols, agriculture régénératrice) sont souvent basées sur des principes ou des cahiers des charges qui ne garantissent pas toujours une réduction des impacts négatifs des pratiques ou un niveau de fourniture de services à la hauteur des promesses annoncées. La littérature fait ressortir les rôles indispensables des microorganismes du sol et du potentiel d'oxydo-réduction (ou rédox) en interaction avec le pH pour la santé du sol et des plantes. L'étude des processus écologiques montre comment il est possible de réduire fortement voire de s'affranchir, progressivement, des énergies fossiles et des intrants de synthèse, en combinant les choix des cultures et intercultures, la gestion de la biomasse, du sol et des intrants de synthèse (type et mode d'application). Sur ces bases, il est possible de contextualiser les pratiques à mettre en oeuvre selon l'état de santé du sol dont un indicateur simple est le rapport matières organiques% / argiles%.

L'association de cultures avec les oliviers – arbre emblématique de la région – est une pratique ancienne en Méditerranée. Cette agroforesterie est reconnue pour fournir de multiples services écosystémiques. En Tunisie, l'un des plus importants pays producteurs d'huile d'olive, les systèmes agroforestiers à base d'oliviers sont peu documentés. Ce travail vise à caractériser les principaux systèmes oléicoles agroforestiers existants au nord et au centre du pays, et à comprendre les raisons qui sous-tendent leur adoption. Pour ce faire, une analyse cartographique a d'abord été réalisée pour appréhender la diversité des milieux oléicoles à l'échelle nationale. Vingt-et-un systèmes oléicoles différents ont été identifiés. Sur cette base, un diagnostic agronomique sur deux sites représentatifs de cette diversité a permis de caractériser la structure des systèmes agroforestiers à l'échelle parcellaire. Cinq types de systèmes agroforestiers à base d'oliviers se distinguent en fonction du choix des espèces associées : cultures maraîchères, polyculture, arbres fruitiers, pâturage pour le cheptel et grandes cultures. Une série d'enquêtes a enfin été réalisée auprès d'agriculteurs pour comprendre les choix d'agencement de ces systèmes et la perception qu'ils en ont. Leur mise en place et les pratiques culturales des agriculteurs sont souvent déterminées par des contraintes économiques ou foncières, et non d'intérêts agronomiques et environnementaux.

Rainfed agriculture is at the centre of many West African economies and a key livelihood strategy in the region. Highly variable rainfall patterns lead to a situation in which farmers' investments to increase productivity are very risky and will become more risky with climate change. Process-based cropping system models are a key tool to assess the impact of weather variability and climate change, as well as the effect of crop management options on crop yields, soil fertility and farming system resilience and widely used by the West African scientific community. Challenges to use are related to their consideration of the prevailing systems and conditions of West African farms, as well as limited data availability for calibration. We outline here a number of factors need to be considered if they are to contribute to the scientific basis underlying transformation of farming systems towards sustainability. These include: capacity building, improved models, FAIR data, research partnerships and using models in co-development settings.

Introduction: Rice plays a critical role in human livelihoods and food security. However, its cultivation requires inputs that are not accessible to all farming communities and can have negative effects on ecosystems. simultaneously, ecological research demonstrates that biodiversity management within fields contributes to ecosystem functioning. Methods: This study aims to evaluate the mixture effect of four functionally distinct rice varieties in terms of characteristics and agronomic performance and their spatial arrangement on the upland rice performance in the highlands of Madagascar. The study was conducted during the 2021-2022 rainfall season at two close sites in Madagascar. Both site differ from each other's in soil properties and soil fertility management. The experimental design at each site included three modalities: i) plot composition, i.e., pure stand or binary mixture; ii) the balance between the varieties within a mixture; iii) and for the balanced mixture (50% of each variety), the spatial arrangement, i.e., row or checkerboard patterns. Data were collected on yields (grain and biomass), and resistance to Striga asiatica infestation, Pyricularia oryzea and bacterial leaf blight (BLB) caused by Xanthomonas oryzae-pv from each plot. Results and discussion: Varietal mixtures produced significantly higher grain and biomass yields, and significantly lower incidence of Pyricularia oryzea compared to pure stands. No significant differences were observed for BLB and striga infestation. These effects were influenced by site fertility, the less fertilized site showed stronger mixture effects with greater gains in grain yield (60%) and biomass yield (42%). The most unbalanced repartition (75% and 25% of each variety) showed the greatest mixture effect for grain yield at both sites, with a strong impact of the varietal identity within the plot. The mixture was most effective when EARLY_MUTANT_IAC_165 constituted 75% of the density associated with other varietie

For centuries, quinoa cultivation was centered only in the Andean countries, and recently it has spread to all regions of the world. Although the number of exporting countries has increased, Bolivia and Peru remain the world's leading producers and exporters. Today, more than 125 countries are experimenting with or cultivating quinoa. The expansion of the crop has only been possible due to the genetic diversity of seeds maintained by generations of farmers in the Andes. As access to quinoa genetic resources in Andean countries remains limited, this implies that the development of new varieties relies on a narrow genetic base relative to the theoretical potential of the species. The use of improved varieties has increased, especially with the emergence of new countries sourcing seed from commercial varieties to start cultivation. To cope with the increasing effects of climate change, it is essential to increase the resilience of crop by taking advantage of their genetic diversity. The current global crisis can only be overcome in the North or in the South by establishing new partnerships for access to genetic resources and the fair and equitable sharing of the benefits of their use. In the last 30 years, quinoa from the Andean countries gained a position in global markets and improved the quality of life of producers. However, at the end of 2015, producer prices collapsed. Quinoa development is dynamic, and now Andean producers face different scenarios with new competitors and new concerns. Being aware of the new reality is essential to face the new challenges responsibly. Analysis at different scales is fundamental, as is promoting local diversity and cooperating towards innovative production systems and inclusive processes that benefit everyone.

In sub-Saharan Africa, maize is one of the most important staple crops, but long-term maize cropping with low external inputs has been associated with the loss of soil fertility. While adding high-quality organic resources combined with mineral fertilizer has been proposed to counteract this fertility loss, the long-term effectiveness and interactions with site properties still require more understanding. This study used repeated measurements over time to assess the effect of different quantities and qualities of organic resource addition combined with mineral nitrogen (N) on the change of soil organic carbon (SOC) contents over time (and SOC stocks in the year 2021) in four ongoing long-term experiments in Kenya. These experiments were established with identical treatments in moist to dry climates, on coarse to clayey soil textures, and have been conducted for at least 16 years. They received organic resources in quantities equivalent to 1.2 and 4 t C ha−1 yr−1 in the form of Tithonia diversifolia (high quality, fast turnover), Calliandra calothyrsus (high quality, intermediate turnover), Zea mays stover (low quality, fast turnover), sawdust (low quality, slow turnover) and local farmyard manure (variable quality, intermediate turnover). Furthermore, the addition of 240 kg N ha−1 yr−1 as mineral N fertilizer or no fertilizer was the split-plot treatment. At all four sites, a loss of SOC was predominantly observed, likely because the sites had been converted to cropland only a few decades before the start of the experiments. Across sites, the average decline of SOC content over 19 years in the 0 to 15 cm topsoil layer ranged from 42 % to 13 % of the initial SOC content for the control and the farmyard manure treatments at 4 t C ha−1 yr−1, respectively. Adding Calliandra or Tithonia at 4 t C ha−1 yr−1 limited the loss of SOC contents to about 24 % of initial SOC, while the addition of sawdust, maize stover (in three of the four sites) and sole mineral N addition show

In this paper, we use conceptual insights from the actor–network theory (ANT) to explore the role of agroecological innovation systems (AeISs) in the reconfiguration of agricultural practices toward sustainability. AeISs are actor networks involving a diversity of individuals (e.g., farmers, traders, experts) and organizations (e.g., cooperatives, rural development agencies, teaching and research institutions) that mainstream agroecology principles and practices to enhance agroecosystems' resilience. Their composition and structure affect the way different agents of change interact, as well as how they access, exchange, and use knowledge as they drive the adoption of specific technologies. We document seven AeISs that were active between 2005 and 2020 in the northern uplands of Laos. Within the framework of these initiatives, action research was conducted for understanding the processes underpinning diverse technical, organizational, and institutional innovations to foster an agroecological transition. Building on a comparative analysis of AeIS, we consider how agency was distributed among collectives as they reorganized in time. Our discussion highlights the importance of configuring, enlarging, and nurturing spaces in which actors are empowered to adjust and adapt, as well as to think and act collectively in complexity. Lastly, what counts in the innovation is the underlying networking process itself, i.e., the process through which all actors of the AeIS interact and exchange. Changes in the networking processes come with a changing conception of knowledge. Moving from knowledge to knowing (i.e., knowledge in the making), AeISs no longer only promote products or technologies, but also collective intelligence based on an ethic of care.

Les services écosystémiques rendus par la biodiversité du sol sont la clé d'une production alimentaire durable. En Martinique, la banane est la principale culture s'étendant sur 26 % de la surface agricole. Elle est cultivée en tant que monoculture d'exportation et subit une forte pression parasitaire nécessitant l'utilisation de produits phytosanitaires et la mise en oeuvre de pratiques souvent nuisibles pour la biodiversité du sol. Il est donc urgent d'identifier et de promouvoir les pratiques innovantes aidant à préserver cette biodiversité. Cette étude vise donc à déterminer l'effet des pratiques agricoles sur les macro-arthropodes du sol. Pour ce faire, nous avons sélectionné 25 parcelles de bananiers de manière à former un gradient de pratiques agricoles dans les agrosystèmes bananiers allant de pratiques agroécologiques aux pratiques intensives en intrants chimiques. Le gradient de pratiques comporte trois catégories représentant des pratiques agricoles contrastées : conventionnel, raisonnée, agroforesterie qui sont complétées par des forêts comme milieu non perturbé et des jachères comme état initial des bananeraies avant la plantation. De plus, nous avons étudié l'effet de la répartition des résidus de culture dans la parcelle, le petit inter-rang étant la zone où les feuilles de bananier sont déposées et le grand inter-rang étant la zone de passage des engins. L'abondance et la diversité des macroarthropodes du sol ont été mesurées par la méthode des quadrats, suivie d'une extraction de la litière et de sol par la méthode de Tullgren. Un total de seize ordres taxonomiques a été répertorié dans l'ensemble des parcelles de cette étude. Cependant, la diversité n'a pas significativement changé selon les pratiques agricoles. Nos résultats ont montré que l'abondance est plus élevée en parcelles raisonnées (1 187±146 ind/m²) que dans les parcelles conventionnelles (971±131 ind/m²). Les détritivores sont le groupe trophique le plus impacté par les pratiques agrico

To promote greater sustainability in agriculture, development of agroecology is increasingly being invoked. What are the conditions for establishing agroecological production in tropical regions? Based upon case studies in several tropical areas, we provide here some answers to this question. We review the “pillars” (i.e. principles) and the “implementation levers” (i.e., tools) for the development of agroecology. We identify three main pillars: (1) the mobilization and management of ecological processes for the sustainable production and the resilience of agroecosystems; (2) the development of interactions between technical, social, environmental, and institutional components of agroecosystems for a holistic approach to agroecology; and (3) the scaling up of agroecology that takes place with a plurality of actions and pathways at different organization levels rather than an increase in resources and a replication of standardized technical processes. To implement these three pillars, we identify 11 main bio-technical, cognitive, socio-political, and organizational levers. Bio-technical levers include those for (1) mobilizing complementarity between crop species to optimize natural resources use, (2) mobilizing functional biodiversity at the plot scale to optimize natural regulation of pests and diseases, (3) managing biodiversity at landscape and territorial scales, (4) increasing the efficiency of biogeochemical cycles, and (5) renewing targets for genetic improvement. Cognitive, socio-political, and organizational levers include those for (6) political and institutional action at the national and global level, (7) action at the local level to support producers, (8) political and organizational action at the territorial level, (9) the marketing and the development of new agri-chains, (10) the development of new methods for evaluating production systems, and (11) the recognition of the values of gender and generation within families and other organisational levels.

Les mosaïques paysagères des régions tropicales humides subissent depuis le milieu du 20ème siècle d'importants changements socio-écologiques qui menacent la résilience des agricultures familiales. Face à ces changements, les paysan.ne.s de certaines régions ont diversifié leurs systèmes agricoles en développant notamment des agroforêts (associations d'arbres avec d'autres espèces non pérennes et/ou des animaux, dans l'espace et dans le temps). Ils mobilisent pour cela la diversité végétale, cultivée ou non, et développent différents modes de gestion de cette agrobiodiversité. Ce travail de recherche vise à analyser ces dynamiques agroforestières au travers d'un cas d'étude situé au sein des paysages de la côte nord-est de Madagascar, qui témoignent d'une évolution récente depuis une agriculture de subsistance associée à la culture sur abattis-brûlis vers une agroforesterie complexe et multi-étagée. Articulée autour de trois parties, ma thèse discute des enjeux de résilience des agricultures familiales en analysant les modes locaux de gestion de l'agrobiodiversité et leurs évolutions en réponse aux changements.La première partie repose sur des travaux de cartographie des modes d'usage des terres qui ont permis de caractériser dans l'espace et dans le temps les dynamiques agroforestières, et d'en analyser les facteurs socio-économiques et physiques. Ces travaux montrent notamment que l'émergence de cette pratique est liée aux évolutions des stratégies paysannes en réponse à divers changements (baisse de la fertilité, variation des prix, croissance démographique entre autres). L'agroforesterie occupe aujourd'hui une surface importante dans les paysages, sa répartition spatiale est notamment liée à la topographie et elle contribue, avec la diversité des autres usages des terres, à l'hétérogénéité paysagère.En prenant l'exemple d'un village, la seconde partie étudie la gestion locale de l'agrobiodiversité en analysant la composition en espèces des agroforêts à giroflier

Smallholder farms that transition to organic and biodiverse production are increasingly recognized as strongholds of agrobiodiversity, with emerging work identifying important outcomes such as enhancing crop portfolios, mitigating extreme climate events and contributing to farmer well-being. Yet the emergent herbaceous communities in these organic systems remain understudied, with the functional diversity and management of this stratum relatively unknown. This study identifies the taxonomic and functional diversity of the herbaceous community in organic coffee agroforestry systems, and describes the extent of this diversity with farm, and farmer, attributes. We measured leaf-level functional traits (e.g. specific leaf area) of the herbaceous community to derive functional diversity indices and collected localized environmental conditions on 15 organic coffee farms in Central Valley, Costa Rica. We also conducted semi-structured interviews with nine farmers to construct mental models on herbaceous community management using a cognitive mapping approach. In total, 38 species from 20 taxonomic families were present in these organic coffee systems. The herbaceous communities were functionally diverse; however, functional evenness increased with canopy openness, suggesting that farms adopting agroforestry tend to have a more functionally diverse herbaceous stratum. Farmer perception of plant traits in the herbaceous community was differentiated into competitive (weeds) or neutral/positive effects. These perceptions aligned with well-established functional trait trade-offs. The mental models representing farmer decision-making processes were highly variable, with a nearly 30% increase in cognitive map density from the simplest map to the most complex; this complexity in mental models was a key explanatory variable in the level of functional diversity of the herbaceous community. Organic management practices that support agroforestry practices also, in turn, promote a func

Promoting plant diversity through crop mixtures is a mainstay of the agroecological transition. Modelling this transition requires considering both plant–plant interactions and plants' interactions with abiotic and biotic environments. Modelling crop mixtures enables designing ways to use plant diversity to provide ecosystem services, as long as they include crop management as input. A single modelling approach is not sufficient, however, and complementarities between models may be critical to consider the multiple processes and system components involved at different and relevant spatial and temporal scales. In this article, we present different modelling solutions implemented in a variety of examples to upscale models from local interactions to ecosystem services. We highlight that modelling solutions (i.e. coupling, metamodelling, inverse or hybrid modelling) are built according to modelling objectives (e.g. understand the relative contributions of primary ecological processes to crop mixtures, quantify impacts of the environment and agricultural practices, assess the resulting ecosystem services) rather than to the scales of integration. Many outcomes of multispecies agroecosystems remain to be explored, both experimentally and through the heuristic use of modelling. Combining models to address plant diversity and predict ecosystem services at different scales remains rare but is critical to support the spatial and temporal prediction of the many systems that could be designed.