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Agroforestry is often seen as a sustainable land-use system for agricultural production providing ecosystem services. Intercropping with food crops leads to equal or higher productivity than monoculture and results in food production for industry and subsistence. Low rubber price and low labor productivity in smallholdings have led to a dramatic conversion of rubber plantations to more profitable crops. The literature analysis performed in this paper aimed at better understanding the ins and outs that could make rubber-based agroforestry more attractive for farmers. A comprehensive search of references was conducted in March 2023 using several international databases and search engines. A Zotero library was set up consisting of 415 scientific references. Each reference was carefully read and tagged in several categories: cropping system, country, main tree species, intercrop type, intercrop product, level of product use, discipline of the study, research topic, and intercrop species. Of the 232 journal articles, 141 studies were carried out on rubber agroforestry. Since 2011, the number of studies per year has increased. Studies on rubber-based agroforestry systems are performed in most rubber-producing countries, in particular in Indonesia, Thailand, China, and Brazil. These studies focus more or less equally on perennials (forest species and fruit trees), annual intercrops, and mixed plantations. Of the 47 annual crops associated with rubber in the literature, 20 studies dealt with rice, maize, banana, and cassava. Agronomy is the main discipline in the literature followed by socio-economy and then ecology. Only four papers are devoted to plant physiology and breeding. The Discussion Section has attempted to analyze the evolution of rubber agroforestry research, progress in the selection of food crop varieties adapted to agroforestry systems, and to draw some recommendations for rubber-based agroforestry systems associated with food crops.

Intercropping, i.e., growing several species in the same field for a major part of their growing periods, often improves yield and weed control, but their performance greatly varies across situations. The aim of this study was to evaluate the effects of bi-species legume–cereal intercrops on weed dynamics and their impact on crop production, in the absence of nitrogen or water stress, via simulations with FlorSys. This individual-based 3D model simulates daily crop–weed seed and plant dynamics over the years, from cropping system and pedoclimate, focusing on competition for light. The study tested seven species proportions in two species mixtures (wheat–faba bean and barley–pea) and nine spatial sowing patterns in three species mixtures (triticale–faba bean, wheat–faba bean, wheat–pea), in both cases comparing the intercrops with the corresponding sole crops (controls). Intercrops and controls were inserted into rotations and simulated over 30 years and repeated with 10 climate scenarios from South-Western France, either with or without weeds. The simulations showed that: (1) the intercrops that best controlled weeds were barley–pea and triticale–faba bean, (2) the spatial pattern alternating one cereal row with one legume row as well as the 67 %-cereal–33 %-legume and 100 %-cereal–50 %-legume species proportions were those that maximised yields and minimised losses due to weeds, (3) the weed biomass in intercrop was greater than or equal to that of the sole cereal, and less than that of the sole legume, and (4) legumes benefitted more from intercropping than cereals because cereals are more competitive against weeds. Intercrop yield was best when combining species with contrasting shading responses (etiolated with stockier plants, leafy with stemmier plants) but early and good plant emergence was essential, particularly for weed suppression.

Background and aims: Intercrops offer multiple advantages over sole crops. The aim of our study was to characterize root growth and interactions in spring wheat/faba bean intercrops to better understand belowground interactions that govern resource capture. Materials and methods: A field experiment was conducted with one faba bean cultivar and two spring wheat cultivars sown at three sowing densities, defining three intercropping designs. Destructive root coring was conducted (0–100 cm) in the intercrops and sole crops at two development stages. FTIR spectroscopy was used to discriminate the species' root masses. The plant-plant interaction index was calculated to represent the belowground interactions. Results: A negative impact of intercropping on total root mass was observed in the treatment with high sowing density in both stages. For the fully and partial replacement design treatments, plant-plant facilitation was more pronounced than competition in all layers. Competition dominated root growth in the treatment with high sowing density in both stages. Lower sowing densities encouraged deep root growth of wheat (both cultivars) in intercropping. The early root growth in depth and in density of one spring wheat cultivar impacted negatively faba bean root growth. Intercropping resulted in a grain yield advantage in both fully and only one partial replacement design treatment. Conclusion: In the intercrops, total root mass and plant-plant interactions were affected more by sowing density than by the spring wheat cultivar. Understanding the effect of sowing density on root growth in intercropping can help to support the design of sustainable intercropping systems.

Agriculture in semi-arid Burkina Faso is dominated by mixed crop-livestock smallholder farms with limited investment capacity in production factors, such as improved seeds, fertilizer and equipment. Hence, to make a living, farmers try to make the best use of available resources based on principles of agro-ecology, including crop diversity and nutrient and biomass recycling. We investigated farm-level management of resources (soil, crops and livestock) through time to assess whether the current management options were able to sustain crop and livestock production and fulfil household food requirements. We ran a one-year detailed farm monitoring campaign in collaboration with 22 volunteer farmers representing the diversity of the farming system in our study area. We quantified inputs and outputs in the cropping system (177 fields) for one rainy season. In addition, the weekly dynamics of crop residues left on field were quantified. Moreover, inflow and outflow of resources at farm level were quantified weekly. The cropping system was characterized by a negative nitrogen balance of about 12 kg N/ha/year, with market-oriented farms and large livestock owners having the most negative balance. Legumes grown (sole and intercropping) contributed to alleviate the nitrogen depletion by adding 15 kg N/ha/year to the nitrogen inputs through atmospheric fixation. However, cereal-legume intercropping did not significantly reduce the nitrogen deficit in comparison to sole cereal cropping mainly because of the small proportion of legumes (8%) in intercropped fields. Livestock grazed crop residues left on the soil (739 kg dry matter/ha on average) at a rate of 26 − 76 kg/ha/week, thus strongly reducing the potential for mulching in the region. Livestock protein requirements were rarely met from farm-produced feed with average feed gaps ranging between 40% and 89% of the daily requirements for small and large herd keepers respectively. Large livestock (cattle) owners relied on trans

Natural rubber is considered a strategic material for the development of Sri Lanka by the Ministry for Plantations. In response to climate change, the country has adopted a policy focusing on resilience and sustainable development. It is in this context that Ksapa initiated the RIVER project in 2022, aiming to develop a program to strengthen agricultural capacity in Sri Lanka. To carry out this project, the company commissioned YAPI Expertise to provide agroforestry intercropping models based on rubber trees with good agronomic performance and economically of interest to producers to diversify their sources of income. The RIVER project is implemented in two districts in south-eastern Sri Lanka: Moneragala and Ampara. This study began with an analysis of the literature in order to select crops that could be intercropped with rubber. In parallel, 80 interviews, prepared by YAPI Expertise, were conducted in the field by a local organisation, LOAM. The aim of these interviews was to identify rubber intercrop models already implemented in the study areas and to understand the reasons why farmers adopted these models. The interviews were analysed statistically by MCA and Chi². By combining these with the literature review, the study established 5 models (Pineapple model, Cocoa model, Banana model, Passion fruit model, Soursop model) for several intercrops that could be planted with rubber, with potential for adoption by local farmers. Finally, selection criteria were established for each model. Both their strong and weak points are presented, since an effective model cannot rely on agronomic analysis alone and it will be essential to adapt the choice of crops to the local market and to farmers' needs.

Cover crops are often mentioned as a way to decrease nutrient losses during the fallow period. Species mixtures of crucifer-legume have been shown to effectively take up nitrogen (N) and sulphur (S) to decrease losses due to leaching, but their ability to simultaneously take up other key macro- and micronutrients remains unknown. Our study assessed the performances of a wide variety of bispecific crucifer-legume mixtures to provide synergetic uptake of multiple nutrients to target nutrient-recycling ecosystem services. Cultivars from eight crucifer and seven legume species were tested as sole and bispecific cover crops at an experimental site near Toulouse, France. Seven macronutrients (C, N, P, K, S, Ca and Mg) and six micronutrients (B, Cu, Mn, Zn, Fe and Na) were measured in both species. Crucifer-legume mixtures showed synergetic uptake of nutrients per ha compared to sole cover crops for some nutrients through niche complementarity and facilitation processes and net competition for other nutrients. Species mixtures induced both i) higher nutrient concentrations for Mn and Fe in crucifers and Ca and B in legumes) and ii) lower concentrations for P, K, Ca and B in crucifers and Cu and Fe in legumes, indicating that the interactions differed among the species mixtures. Nevertheless, the nutrient uptake measured in shoots were always higher in species mixtures than in sole crops (LER > 1) demonstrating the compatibility and complementarity of crucifer and legume mixtures in providing multiple-nutrient catch-crop and recycling related ecosystem services. Despite overall positive interactions and synergetic complementarities, the results also highlight that some net negative competition occurred for some nutrients. Thus, further investigation is still necessary to completely understand the processes behind multiple-nutrient acquisition in species mixtures.

The growing demand for sustainable agriculture is raising interest in intercropping for its multiple potential benefits to avoid or limit the use of chemical inputs or increase the production per surface unit. Predicting the existence and magnitude of those benefits remains a challenge given the numerous interactions between interspecific plant-plant relationships, their environment, and the agricultural practices. Soil-crop models are critical in understanding these interactions in dynamics during the whole growing season, but few models are capable of accurately simulating intercropping systems. In this study, we propose a set of simple and generic formalisms (i.e. the structure and mathematical representation necessary for designing a model) for simulating key interactions in bi-specific intercropping systems that can be readily included into existing dynamic crop models. This requires simulating important processes such as development, light interception, plant growth, N and water balance, and yield formation in response to management practices, soil conditions, and climate. These formalisms were integrated into the STICS soil-crop model and evaluated using observed data of intercropping systems of cereal and legumes mixtures, including Faba bean-Wheat, Pea-Barley, Soybean-Sunflower, and Wheat-Pea mixtures. We demonstrate that the proposed formalisms provide a comprehensive simulation of soil-plant interactions in various types of bispecific intercrops. The model was found consistent and generic under a range of spring and winter intercrops (nRMSE = 25% for maximum leaf area index, 23% for shoot biomass at harvest, and 18% for grain yield). This is the first time a complete set of formalisms has been developed and published for simulating bi-specific intercropping systems and integrated into a soil-crop model. With its emphasis on being generic, sufficiently accurate, simple, and easy to parameterize, STICS is well-suited to help researchers designing in silico

Cereal-legume intercropping has been traditionally practiced across West Africa by farmers and provides resilience of agriculture to climate variability. Intensification of these extensive intercropping systems in order to meet future food demand is critical. This study aims at evaluating the agronomic performance of the intensification of millet-cowpea intercropping with low cowpea density, and its variation with climate variability, using an on-station experiment in Bambey, Senegal. Two trials (irrigated vs rainfed) were set up to compare millet sole- and inter-cropping with a grain and a fodder variety of cowpea, in 2018 and 2019. Two levels of fertilization were tested: 0 kg(N) ha−1 and 69 kg(N) ha−1. The two cropping years were contrasting and water stress around flowering and/or during grain filling (indicated by the Fraction of Transpirable Soil Water) was higher in 2019 than in 2018 in the rainfed experiment. In both experiment and for all treatments, land equivalent ratio (LER) in the intercropping was 1.6 and 1.4 for grain and biomass respectively. Millet aboveground biomass was significantly higher in intercropping than in sole cropping in the irrigated experiment but not in the rainfed experiment. In the rainfed experiment, the interaction between cropping system and year was significant, so that millet aboveground biomass was greater in intercropping than in sole cropping in 2018 (year of lower water stress) but not in 2019 (year of higher water stress). The effect of fertilization on millet aboveground biomass did not significantly interact with cropping system (sole vs intercrop). For grain yield, fertilization interacted significantly with the cropping system in the irrigated trial: the benefits of intercropping on millet grain yield were greater with 69 kg(N) ha−1 than with 0 kg(N) ha−1. This significant interaction could not be observed in the rainfed trial, potentially due to water stress. These results show that the level of water stress (related

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

Agroecological studies on sugarcane intercropping commonly generate complex datasets. A generic database (AEGIS – Agro-Ecological Global Information System) has been developed to facilitate the use of these datasets. The data described in this paper includes data from 8 experiments carried out on Reunion Island from 2012 to 2021 under three soil and climatic conditions to assess the capacity of cover crops in the sugarcane inter-row to control weed growth. Each experiment consisted of the comparison of three treatments in the inter-row: i) sugarcane with chemical weeding, ii) sugarcane with a cover crop sowed in the inter-row, and iii) sugarcane with spontaneous weed flora in the inter-row. The datasets contain data for sugarcane and cover crop observations (e.g., yield), weed flora, including 104 weed species (e.g., ground cover), crop management (including manual and chemical weedings), soil analyses, and daily weather. This dataset provides an adequate experimental dataset to calibrate or validate crop model simulations under intercropping.

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.

Intercropping of trees with crops on the same piece of land at a given time has been hypothesized to: enhance crop yield, increase land-use and improve land equivalent ratio (LER). To address this hypothesis, we evaluated two legumes faba bean, lentil and three cereals durum wheat, soft wheat and barley grown in olive (Olea europea) agroforestry during two growing seasons (Y) with contrasting weather (Y1: 2015-2016 and Y2: 2016-2017) under a Mediterranean climate of north western Morocco. We assessed the effect of annual crops on olive growth and yield; the effect of trees on annual crop growth, yield components, and final yields; finally, we calculated the land equivalent ratio (LER) of olive agroforestry to assess the productivity of the associations. Legumes had no effect on olive growth and yield, while cereals negatively affected shoot elongation and olive yield compared to olive in sole crop. Olive limited crop growth and yield of all associated crops and yield reduction was around 33 % for legumes and 47 % for cereals in agroforestry than sole crop. The magnitude of reduction was higher in Y1 than Y2. Similar responses were found when comparing crops at different distances from trees. Annual crops generally had lower biomass and yield, near the trees compared to the middle of tree inter-rows, causing significant spatial heterogeneity in crops. The LER reached 1.36 with lentil and 1.33 with faba bean, the lowest LER was recorded with durum wheat in both years with 1.01 in Y1 and 1.02 in Y2, and the highest LER with cereals was registered with soft wheat and reached 1.19 in Y1.

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%.

Background: The adoption of innovative cropping systems with low pesticide inputs would reduce environmental degradation and dependency on the use of plant protection products. Evaluating the pesticide risk to human health is a growing concern in the assessment of the sustainability of cropping practices. The assessment of human health risks linked to pesticide use in either conventional or innovative cropping systems is poorly documented in the literature. Objectives: This study focused on the assessment of pesticide exposure and human health risks from pesticide use in arable cropping systems (two monoculture and one intercropping system) associated with the use of various tillage practices (conventional tillage, reduced tillage, and no tillage). Methods: Human exposure (operators and residents) and health risks from pesticide use were assessed and compared between three conventional and six innovative cropping systems. We used the previously published BROWSE (Bystanders, Residents, Operators, and WorkerS Exposure) model based on data collected from interviews with the farmers and expert knowledge to compare the human health risk from pesticide use in the Setif area. Environmental conditions and the physical characteristics of the farmers were collected on three different farms from 2019 to 2021. Results: The modelling results demonstrate that human exposure to pesticides was systematically high under conservation tillage (no or reduced tillage) and monoculture cropping (pea and barley) conditions. It was also confirmed that operators experienced the highest cumulated exposure to pesticides (56 mg kg−1 bw day−1), followed by resident children seven days after pesticide application (0.66 mg kg−1 bw day−1). BROWSE simulations showed that dermal absorption was the most dominant route and represented more than 98% of the total amount of pesticides applied in all cropping × tillage system combinations. Regarding the overall results of the simulated human health risk, b

Diversified cropping systems, especially those including legumes, have been proposed to enhance food production with reduced inputs and environmental impacts. However, the impact of legume pre-crops on main crop yield and its drivers has never been systematically investigated in a global context. Here, we synthesize 11,768 yield observations from 462 field experiments comparing legume-based and non-legume cropping systems and show that legumes enhanced main crop yield by 20%. These yield advantages decline with increasing N fertilizer rates and crop diversity of the main cropping system. The yield benefits are consistent among main crops (e.g., rice, wheat, maize) and evident across pedo-climatic regions. Moreover, greater yield advantages (32% vs. 7%) are observed in low- vs. high-yielding environments, suggesting legumes increase crop production with low inputs (e.g., in Africa or organic agriculture). In conclusion, our study suggests that legume-based rotations offer a critical pathway for enhancing global crop production, especially when integrated into low-input and low-diversity agricultural systems.

Dans la zone soudano sahélienne d'Afrique de l'Ouest, la productivité agricole est fortement affectée par la variabilité et les changements climatiques. La production agricole est dominée par la production pluviale de céréales telles que le maïs, le mil et le sorgho, pour la consommation alimentaire. Les agriculteurs ont des rendements faibles et variables, ce qui entraîne une incertitude croissante quant à leur capacité à produire davantage pour nourrir une population en forte croissance. L'objectif général de cette thèse était de concevoir des systèmes de culture plus productifs et stables, adaptés au changement climatique, en explorant les bénéfices de l'association sorgho-niébé, combiné a des choix contrastés de variété de sorgho, de fertilisation minérale et de date de semis. L'approche était basée sur un travail d'enquête, d'expérimentation au champ et de simulation à l'aide d'un modèle de culture, pour un cas d'étude au centre du Mali en Afrique de l'Ouest. Une première étape a porté sur l'identification de la perception du changement climatique par les agriculteurs et les stratégies d'adaptation agricole qu'ils considèrent pertinentes pour faire face à la variabilité et au changement climatique. En second lieu, le modèle de culture STICS a été calibré sur la base de deux années d'expérimentation (2017, 2018) de la culture associée sorgho-niébé à la station agronomique de N'Tarla. Dans ce dispositif expérimental, deux variétés de sorgho (locale et améliorée) avec une sensibilité contrastée à la photopériode ont été étudiées en culture pure et en culture associée avec le niébé. Deux dates de semis et deux niveaux de fertilisation minérale ont également été étudiés.

Sorghum is an important staple crop in Sub-Saharan Africa. In the Sudano-Sahelian zone of West Africa, sorghum is mainly intercropped with cowpea, but these intercropping systems are facing low-productivity problems. The overall aim of this research was to identify sorghum varieties with different agro-morphological and physiological traits that could improve the performance of the intercropping systems. We followed a two-step methodology comprising (i) identification of varieties and plant traits of interest in intercropping systems, using participatory methods, and (ii) agro-morpho-physiological characterization of 50 sorghum varieties, to examine the range of variation in traits of interest. The results show that landraces are the varieties most widely used by farmers, and that 82.5% of farmers consider the variety type they choose for intercropping to be important. Farmers mentioned plant height, number of leaves and stem diameter as important traits to consider. Analysis of variance showed significant differences between varieties for half of the 24 agro-morpho-physiological traits studied. Hierarchical clustering identified three main groups of varieties, distinguished by morphological traits such as stem diameter, total number and size of leaves (group 1), root traits (depth, growth angle, dry matter) and relative chlorophyll content (groups 2 and 3). Based on this classification, we recommend several varieties from each of the three groups, exhibiting contrasting traits, for an assessment of their performances in intercropping systems.

L’agriculture intensive moderne cause plusieurs problèmes environnementaux à l’échelle mondiale. L’Afrique subsaharienne est particulièrement affectée par une perte de fertilité des sols agricoles due principalement au remplacement des méthodes agricoles traditionnelles par la culture du maïs en monoculture. Dans le miombo africain, cette perte de fertilité ainsi que le manque d’accès aux engrais inorganiques affecte grandement la sécurité alimentaire des habitants. Depuis quelques décennies, des techniques de régénération de la fertilité des sols sont proposées dans la région. L’objectif de cet essai est de déterminer les effets de ces techniques sur la productivité agricole, la situation économique et la sécurité alimentaire ainsi que de fournir des recommandations pour leur adoption par les communautés locales. Cet essai illustre, grâce à une revue de littérature, les nombreux bénéfices environnementaux et sur les récoltes de l’utilisation des techniques de régénération de la fertilité des sols proposées dans la région à l’étude. Parmi ces techniques, l’utilisation de légumineuses dans les terres agricoles peut également permettre d’améliorer la sécurité alimentaire des agriculteurs et de leur famille lorsque celles-ci sont consommées. Cependant, l’adoption de ces techniques dans la région est ralentie par plusieurs facteurs de nature socioéconomique, politique et environnementale. Les recommandations proposées pour augmenter l’adoption de ces techniques visent majoritairement la plus grande implication des gouvernements des pays de la région et la reconnaissance de l’importance de la consultation et de l’éducation des communautés locales. Il est également recommandé de combiner l’utilisation de légumineuses et d’engrais organiques ou inorganiques lorsque nécessaire et lorsque la situation le permet. Les techniques de régénération de la fertilité des sols de la région du miombo sont un exemple parmi plusieurs autres d’une application des principes de l’agricultur

European cropping systems are often characterized by short rotations or even monocropping, leading to environmental issues such as soil degradation, water eutrophication, and air pollution including greenhouse gas emissions, that contribute to climate change and biodiversity loss. The use of diversification practices (i.e., intercropping, multiple cropping including cover cropping and rotation extension), may help enhance agrobiodiversity and deliver ecosystem services while developing new value chains. Despite its benefits, crop diversification is hindered by various technical, organizational, and institutional barriers along value chains (input industries, farms, trading and processing industries, retailers, and consumers) and within sociotechnical systems (policy, research, education, regulation and advisory). Six EU-funded research projects have joined forces to boost crop diversification by creating the European Crop Diversification Cluster (CDC). This Cluster aggregates research, innovation, commercial and citizen-focused partnerships to identify and remove barriers across the agrifood system and thus enables the uptake of diversification measures by all European value-chain stakeholders. The CDC will produce a typology of barriers, develop tools to accompany actors in their transition, harmonize the use of multicriteria assessment indicators, prepare policy recommendations and pave the way for a long-term network on crop diversification.

Modern agriculture needs to develop transition pathways toward agroecological, resilient and sustainable farming systems. One key pathway for such agroecological intensification is the diversification of cropping systems using intercropping and notably cereal-grain legume mixtures. Such mixtures or intercrops have the potential to increase and stabilize yields and improve cereal grain protein concentration in comparison to sole crops. Species mixtures are complex and the 4C approach is both a pedagogical and scientific way to represent the combination of four joint effects of Competition, Complementarity, Cooperation, and Compensation as processes or effects occurring simultaneously and dynamically between species over the whole cropping cycle. Competition is when plants have fairly similar requirements for abiotic resources in space and time, the result of all processes that occur when one species has a greater ability to use limiting resources (e.g., nutrients, water, space, light) than others. Complementarity is when plants grown together have different requirements for abiotic resources in space, time or form. Cooperation is when the modification of the environment by one species is beneficial to the other(s). Compensation is when the failure of one species is compensated by the other(s) because they differ in their sensitivity to abiotic stress. The 4C approach allows to assess the performance of arable intercropping versus classical sole cropping through understanding the use of abiotic resources.

Au Maroc, les systèmes agroforestiers à base d'olivier sont très répandus et diversifiés. Ce travail vise à caractériser leur diversité et leurs performances dans la région de Moulay Driss Zerhoun, au Nord du Maroc. Pour ce faire, 72 enquêtes ont été réalisées auprès des agriculteurs. Pour chaque exploitation, les systèmes agroforestiers ont été comparés à des systèmes de culture pure et à des vergers d'oliviers purs. En condition pluviale, l'insertion des légumineuses et des céréales dans les oliveraies constitue la pratique dominante. Il y a des différences très significatives de rendements pour les cultures annuelles et pour les oliviers entre systèmes associés d'agroforesterie, témoins en cultures annuelles pures et témoins en verger d'olivier. Le Land Equivalent Ratio (surface équivalente assolée) des rendements et celui des marges brutes sont toujours supérieurs à 1 avec les céréales et les légumineuses en agroforesterie. Nos résultats suggèrent que les systèmes agroforestiers sont plus productifs, rentables et efficients que les cultures pures. L'agroforesterie constituerait donc une stratégie pour une production durable, mais il faudrait d'autres expérimentations pour mieux appréhender la productivité de ces systèmes et préciser leurs atouts et leurs limites.

In the cotton-production zone of Burkina Faso, poor soil fertility and limited access to appropriate fertilizers call for alternative approaches to sustain productivity, such as the introduction of more legumes into the agroecosystem. Legumes have nearly disappeared from local cropping systems under the pressure of the cotton monocropping model. To develop new legume-based cropping systems using a bottom-up approach, this study was based on local farmers' agroecological innovations. In a first step, called on-farm innovation tracking, five innovative legume-based cropping systems were identified and characterized on farms located in the study area through interviews with “innovative farmers” who had designed and implemented these cropping systems: (i) Sorghum and legume (cowpea, soybean or peanut) intercropping in rotation with maize or cotton; (ii) Soybean as a cash crop in rotation with maize or cotton; (iii) Red cowpea intra-annual succession with a biomass crop; (iv) Mucuna in rotation with maize; and (v) Pigeon pea in rotation with maize. In a second step, these five “innovative cropping systems” (ICSs) were implemented in “participatory prototyping trials” (PPTs) in two communities located in the study area were they were evaluated during field days by local farmers (“field-day farmers”) having no previous experience with ICSs. By comparing evaluations made by innovative farmers with those of field-day farmers, it was shown that (i) locally implemented ICSs adapted to local drivers of change are of great interest to other farmers, and (ii) the study's two-step participatory approach is an original and relevant way to co-design and introduce innovations.

The modeling of carbon (C) and nitrogen (N) fluxes between microorganisms and plants in pure and associated cultures of durum wheat and faba bean demonstrated a close link between the C and N cycles in agroecosystems. The MOMOS (microorganisms and organic matter of soils) model integrates simplified descriptions of photosynthesis (origin of organic C in soil), N microbial exchange (soil origin for N), N fixation (atmospheric origin for N), and plant growth with an organic matter decomposition core that has the soil microbial community at its center. This work provides estimates of the exchange parameters between plant organs and microbes, which were compared to literature data when available. In a connection with photosynthesized C, the root demand for inorganic N can be adjusted by its microbial production. Our approach is a new methodology for improving plant production, by optimizing the interactions with soil microorganisms. Additionally, the coupling of plant growth and microbial processes enabled determining changes of the organic compartments of soil. In the unfertilized limestone soil of this study, sequestration was found to be located in the labile microbial metabolites for one year, then significantly transferred to stable humus during 6-year intercropping. Thus, we propose the MOMOS mathematical tool, not only for guiding ecological intensification, but also related to the management of agroecosystems for climate change mitigation.

Around 30% of global food is produced by smallholder farmers, yet they constitute the most food-insecure group. In Mexico, food self-sufficiency is declining. Rural policies in the country have stimulated the production of cash crops to the detriment of the traditional intercropping system, the milpa. Such a decline may have negative consequences for the food security of subsistence farmers. This study aimed to assess changes in nutritional self-sufficiency over the last 30 years and the role of milpa systems in food security for two communities in the highlands of Oaxaca, Mexico. The study used satellite images, censuses, and field data to estimate food production. Three cropping systems, monoculture of maize, monoculture of common bean, and the milpa were compared in terms of nutrients and vitamins produced. Furthermore, a household typology was developed for each community to contrast nutritional self-sufficiency levels between the different household types. Results showed that the milpa produced more volume of food per area compared to the other systems. The milpa also produced all the nutrients and vitamins (except for B12) required to feed at least 2 persons ha-1. Monocultures of maize lacked vitamins A, B9, B12, and C, and the common bean lacked vitamins A, B12, and C. While farmers recognized the importance of the milpa, they preferred monocultures due to the reduced labor demands of this system. Households that obtained most of their income from off-farm activities had the lowest nutritional self-sufficiency. Enhancing nutritional self-sufficiency through crop diversification has the potential to not only improve the nutrition of subsistence farmers, but also to enhance ecosystem service provision, promote biodiversity conservation and restoration, and improve resilience to climate change.

In this article we explore the concept and implications of three-dimensional (spatial, temporal, and genetic) in-field crop diversification to inform systems redesign towards ecological intensification. We first present a conceptual framework for classifying diversity in arable contexts. We then apply the framework to analyse two long-term systems experiments in The Netherlands where spatial and genetic diversity measures were implemented via strip and mixed intercropping with the aim to increase ecosystem service delivery: incidence and spreading rate of late blight (Phytophthora infestans) in potato (Solanum tubersosum L.), and biocontrol control potential in wheat (Triticum aestivum L.). In the case of late blight, potatoes planted in strips had significantly lower disease incidence than the monoculture reference across all years, and adding cultivar mixing within the strip was more powerful in mitigating late blight than spatial diversification alone. In the case of biocontrol in wheat, strips supported significantly larger (for all but one taxonomic group) and significantly more diverse epigeic natural enemy populations than the sole culture reference in all years. However, the addition of species mixing within strips did not further increase biocontrol indices compared to sole-wheat strips. These results imply that compromises between management complexity and ecosystem service enhancement are achievable through strip cropping, an operable practice with current machinery, and one that does not require a thorough reconfiguration of the production system. The three-dimensional diversity framework proved useful for unpacking experimental outcomes in terms of diversity-mediated mechanisms, however it requires further development before it can be used to facilitate multi-objective optimization.

Face aux besoins d'innovation de plus en plus urgents, il est nécessaire de développer des approches permettant de co-concevoir des Systèmes de Cultures Innovants (ICS) appropriables par les producteurs et adaptés aux conditions locales d'accès aux ressources. Pour ce faire, nous proposons une articulation originale de différents outils de co-conception, tels que la traque aux innovations, des Essais de Prototypage Participatifs (EPP), des ateliers de conception et d'évaluation, et des essais paysans de conception pas à pas. Cette démarche a été conduite avec 73 producteurs appartenant à deux communautés villageoises de la zone cotonnière du Burkina Faso.Nous montrons que (i) Certaines options techniques mises en place par des producteurs innovants du territoire anticipent différent facteurs de changement de la zone, et intéressent d'autres producteurs; (ii) On peut impliquer une grande diversité de producteurs par la mise en démonstration et en débat d'options techniques variées techniquement accessibles, que l'on fait évoluer en prenant en compte l'évaluation des producteurs et qui conviennent à leurs accès aux ressources ; (iii) Par la mise en expérimentation dans leurs exploitations, les producteurs adaptent ces options innovantes à leurs situations particulières, et entrent dans un processus de conception pas-à-pas de systèmes de culture innovants, processus nourri par les échanges entre pairs et avec les agronomes.Ainsi, en soumettant des innovations mises au point par des producteurs du territoire à l'évaluation collective d'autres producteurs, nous avons initié, au sein d'une grande diversité de systèmes de productions, la conception pas-à-pas de ICS adaptés à chaque situation individuelle.

European cropping systems are often characterized by short rotations or even monocropping, leading to environmental issues such as soil degradation, water eutrophication, and air pollution including greenhouse gas emissions, that contribute to climate change and biodiversity loss. The use of diversification practices (i.e., intercropping, multiple cropping including cover cropping and rotation extension), may help enhance agrobiodiversity and deliver ecosystem services while developing new value chains. Despite its benefits, crop diversification is hindered by various technical, organizational, and institutional barriers along value chains (input industries, farms, trading and processing industries, retailers, and consumers) and within sociotechnical systems (policy, research, education, regulation and advisory). Six EU-funded research projects have joined forces to boost crop diversification by creating the European Crop Diversification Cluster (CDC). This Cluster aggregates research, innovation, commercial and citizen-focused partnerships to identify and remove barriers across the agrifood system and thus enables the uptake of diversification measures by all European value-chain stakeholders. The CDC will produce a typology of barriers, develop tools to accompany actors in their transition, harmonize the use of multicriteria assessment indicators, prepare policy recommendations and pave the way for a long-term network on crop diversification.

Background and Aims: Improved modelling of carbon assimilation and plant growth to low soil moisture requires evaluation of underlying mechanisms in the soil, roots, and shoots. The feedback between plants and their local environment throughout the whole spectrum soil-root-shoot-environment is crucial to accurately describe and evaluate the impact of environmental changes on plant development. This study presents a 3D functional structural plant model, in which shoot and root growth are driven by radiative transfer, photosynthesis, and soil hydrodynamics through different parameterisation schemes relating soil water deficit and carbon assimilation. The new coupled model is used to evaluate the impact of soil moisture availability on plant productivity for two different groups of flowering plants under different spatial configurations. • Methods: In order to address different aspects of plant development due to limited soil water availability, a 3D FSP model including root, shoot, and soil was constructed by linking three different well-stablished models of airborne plant, root architecture, and reactive transport in the soil. Different parameterisation schemes were used in order to integrate photosynthetic rate with root water uptake within the coupled model. The behaviour of the model was assessed on how the growth of two different types of plants, i.e. monocot and dicot, is impacted by soil water deficit under different competitive conditions: isolated (no competition), intra, and interspecific competition. • Key Results: The model proved to be capable of simulating carbon assimilation and plant development under different growing settings including isolated monocots and dicots, intra, and interspecific competition. The model predicted that (1) soil water availability has a larger impact on photosynthesis than on carbon allocation; (2) soil water deficit has an impact on root and shoot biomass production by up to 90 % for monocots and 50 % for dicots; and (3) the

The symbiotic association (plant-soil-microorganisms) has an important role in nitrogen (N) and phosphorus (P) uptake. The main objective of this study is to assess the potential of fungal and rhizobial symbionts as well as the importance of plant-soil-microorganism interactions on microbial dynamics. The upland rice and the beans were cultivated in mono or in co-culture using the rhizospheric soil of the upland rice and beans collected on plots treated with different levels of organic and mineral fertilizers. What about saying: Microbial (fungal and rhizobial) inoculate were constituted by root fragments (rice or bean) collected from previous crop and coded as I1 (root fragments from rice), I2 (root fragments from bean) and I3 (mixed root fragments from rice and bean). The results showed that soils inoculated with I1 and I3, were characterized by high phosphatase activity. These two treatments enhance also the amount of nitrogen and phosphorus in the aerial part of upland rice intercropped with bean. These results suggest that the bean with its symbiont can be considered as ecological engineers that stimulate the biological functioning of soils and is beneficial for upland rice cultivation.