In La Réunion, pineapple is the main fruit crop, but it is threatened by Pineapple Mealybug Wilt-associated Viruses, which are vectored by Dysmicoccus brevipes (Cockerell, 1893). In a context where control methods are drastically limited, new management strategies must be examined, including the use of local natural enemies. In this study, we evaluated the potential of three predator species present in La Réunion and known to prey on mealybugs as biological control agents of D. brevipes: the ladybirds Exochomus laeviusculus Weise, 1909 (Coleoptera: Coccinellidae) and Nephus apolonia Magro Almeida, 2020 (Coleoptera: Coccinellidae) and the brown lacewing Psectra iniqua (Hagen, 1859) (Neuroptera: Hemerobiidae). Stage-specific predation assays were conducted under laboratory conditions using four developmental stages of D. brevipes, and predator development was monitored over a 30-day period. Among the three species tested, E. laeviusculus exhibited the highest predation rates and was the only predator able to complete its development on D. brevipes. Predation was significantly higher on first- and second-instar nymphs than on older nymphs and adults, indicating a preference for early developmental stages. Conversely, N. apolonia and P. iniqua failed to complete development on D. brevipes, with predation restricted to adults feeding on early developmental stages of the pineapple mealybug.

Allo-inoculum has an important role in fungal disease epidemiology. Understanding the factors that impact the long-distance dispersal of a pathogen is crucial to improve its management. In this study, we studied Pseudocercospora fijiensis allo-inoculum dynamics in Martinique over a period of 18 months. We used trap plants to measure (10 times) the spore abundance across six locations. Lesion densities observed on trap plants were used as a proxy of the allo-inoculum resulting from long-dispersal ascospores. We analyzed how the lesion densities of P. fijiensis measured with trap plants were statistically correlated with (i) weather factors and (ii) the stage of evolution of disease (SED) measured in closest banana plots. The SED measured in neighboring plots did not significantly influence the lesion densities observed on the trap plants. For each variable, we determined the period of time prior to the trap plant exposure that exhibited the strongest correlation with the lesion densities measured on these plants. Rainfall was the variable with the most influence and positively correlated with lesion densities when measured 7 to 4 days before trap plant exposure. Inversely, there was a negative correlation with UV radiation measured 2 to 1 days prior to trap plant exposure. This information complements the knowledge on the biology of the fungus and holds potential for enhancing disease management, especially the importance of rainfall for the allo-inoculum dynamics. These results also showed that if commercial farms have good management of black leaf streak disease, it does not contribute to long-distance contamination.

Honeydew-producing hemipterans establish mutualistic interactions with ants, which collect honeydew while providing protection against natural enemies and other services. Although this association benefits hemipterans, it often exacerbates crop damage by increasing pest abundance. Providing alternative sugar resources has been proposed as a strategy to disrupt these associations, but its effectiveness remains poorly tested in tropical agrosystems. Here, we investigated whether sugar feeders could reduce ant-mealybug mutualism in pineapple (Ananas comosus) fields on La Réunion, where the mealybug Dysmicoccus brevipes, a vector of Pineapple Mealybug Wilt-associated viruses (PMWaVs), poses a major threat to production. We deployed sugar feeders in replicated field plots and monitored ant, mealybug and predator abundances over eleven months, complemented by sentinel prey assays to quantify ant-mealybug interaction rates and mealybug removal. Mealybug abundance was positively associated with ant presence, while sugar supplementation reduced ant abundance by 42% on pineapple plants compared to controls. Predator abundance was 105% higher in supplemented zones, likely due to both direct nutritional benefits and lower ant interference, but declined with distance from feeders. Three ant species, Solenopsis geminata, Pheidole megacephala and Brachymyrmex cordemoyi accounted for most interactions with mealybugs, with species-specific temporal dynamics but no response to sugar supplementation. Sugar supplementation represents a promising management lever, but its effect on mealybug remains context-dependent. Integrating sugar provisioning with complementary agroecological practices, such as biological control and habitat diversification, may maximize its impact and contribute to sustainable management of pineapple mealybug wilt disease.

Ants are one of the most widespread groups of insects, but the mechanisms allowing them to coexist despite having similar nutritional needs remain unclear. In this study, we investigated the structure and competitive dynamics of ant assemblages in pineapple agrosystems of La R & eacute;union Island. Using an imagery approach that combined in-field image captures and a computer vision algorithm based on convolutional neural networks, we analyzed ant dominance hierarchies, foraging and recruitment behaviors, niche partitioning between day and night, as well as the impact of environmental variables. This approach provided highly detailed data on the strategies of individual species. Additionally, to better understand the resource exploitation strategies employed by ant species, we then tested the discovery-dominance trade-off. Our results revealed that Pheidole megacephala and Solenopsis geminata were the two dominant species, displaying high recruitment investment and frequent bait monopolization, particularly at night. In contrast, Brachymyrmex cordemoyi used a scout-based foraging strategy that allowed it to rapidly locate baits and maintain moderate dominance levels, during both day and night periods. With lower abilities to discover and control baits, subordinate species had to rely on alternative foraging strategies to persist. We found a significant positive correlation between the discovery and dominance abilities supporting a discovery-defense strategy rather than a discovery-dominance trade-off. This finding implies that resource monopolization in simplified ecosystems may benefit species optimizing both rapid resource location and competitive defense. Environmental factors, including plant species richness, plant cover, and mulch cover, influenced species abundance and occurrence, even though dominant species appeared to remain unaffected by habitat variations. The impacts of environmental factors highlight the role of habitat complexity in mediating competitive interactions shaping ant coexistence.

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.

Cosmopolites sordidus is one of the major pests of bananas. The ban on the use of pesticide products as well as the firmness of public opinion on these products makes it imperative to adopt an alternative method that respects the environment. Pheromone mass trapping is a method that meets these conditions and has demonstrated its effectiveness. However, no study has focused on its use in fallow plots, even though fallowing is recognized as an event that makes plots a source of contamination. Our study compares the effectiveness of two fallow trapping patterns by integrating the effect of climatic variables on the capture rate. Our results showed that the trapping of fallow land ensures a real sanitation of C. sordidus. In addition, the internal trapping of fallow land, compared to trapping surrounding the fallow land, cleans up the plots twice as quickly. Furthermore, trapping efficiency is affected by climatic conditions with seasonal variations, the wet season is more favorable to trapping than the dry season. We provide recommendations for the use of trapping considering the effect of climate on the movement of weevils and on the efficiency of pheromone attractivity. Finally, we offer perspectives on the gaps that still need to be filled.

Under the pressure exerted by humans on forest ecosystems, agroforestry is promoted to maintain a balance between forest and agricultural ecosystems. Agroforestry systems are the center of interactions between crops and other plants and between fauna and flora. Within this faunistic diversity, ants occupy a prominent place through their protective association with some tropical plant species as natural enemies of their arthropod pests. In this study, we analyzed the effects of the diversity of trees associated with cashew trees and of cashew tree density on ant abundance/diversity in cashew agroforestry systems. The study was conducted in 12 cashew orchards in central Benin. Data on the diversity and densities of ground-dwelling and arboreal ant species were collected using hand and bait traps. The diversity of trees in the orchards and cashew tree density were also determined. Twenty ant species were collected among which the most abundant were Pheidole spp., Lepisiota sp., Paratrechina longicornis, Camponotus sericeus, Brachyponera sennaarensis, Camponotus spp., and Oecophylla longinoda. Tree diversity and cashew tree density in those orchards had significantly positive effects on the ant densities but not on ant diversity. Structural equation modeling showed that the abundance of ants increased the diversity of ants, which decreased the herbivory index. Based on the important role of ants as biological pest control agents, it is worth promoting agroforestry systems in cashew orchards to increase ant abundance, thereby improving their productivity.

Agroforestry systems (AFS) are gaining major interest in cocoa producing countries. However, the analysis of competition effects in multispecific complex agricultural systems remains a key lock-in preventing both (i) a thorough understanding of resource partitioning, and (ii) the co-design of spatial patterns and management of cocoa AFS (cAFS) minimising competition. We sampled 48 cAFS 1000 m2 plots in Central Cameroon and used an individual based approach to analyse the effect neighbouring tree community composition had on coca tree pod production. First, we determined the distance up to which each neighbouring tree influenced the production of a given cocoa tree and checked for the significance and the magnitude of this effect. We then explored the trade-offs between cocoa tree production and the abundance of associated trees. Our results first underline a significant intra-specific competition within the cocoa tree populations studied, which would need to be thinned down to 800-1100 individuals per ha. We also found a general negative effect of associated trees kept or grown for their fruits (e.g. mango, traditional species, citrus trees). Those effects were stronger when the trees were positioned between 6 and 11 m away from the cocoa trees. These trees clearly impaired pod production, especially for small diameter cocoa trees. Palm trees, however, had a positive effect on cocoa pod production, with suitable densities modelled ranging from 0 to 240 individuals per ha. Finally, we found both positive and negative effects of associated forest trees on cocoa pod production, which varied with the distance separating them from the cocoa trees and the size of the cocoa trees. Overall, our analyses show that cocoa production in complex cAFS is influenced both by intra-and inter-specific interactions while it remains difficult to distinguish between potential intertwined effects and resource limitations.

BACKGROUND:Hedgerows represent an agroecological lever for pest management. To date, few studies have shown that they can be used as a lever for the control of aerial fungal diseases, especially as a barrier to dispersal. On banana production, the main disease is black leaf streak disease (BLSD), which is a fungal disease caused by Pseudocercospora fijiensis. This pathogen disperses through two types of spores: ascospore and conidia. The aim of this study was to observe and to quantify the effect of hedgerows on BLSD dispersal. Trap plants were placed at the same distance to an artificial source of inoculum with a hedgerow on one side. Lesions were counted to establish the daily lesion density of each trap plant. The combination of hedgerow characteristics such as height, width, and optical porosity were used to evaluate its potential capacity to intercept spores. RESULTS:When ascospores were used as a source of inoculum, the lesion density on traps plant decreased up to 50% between the hedgerow with the lowest interception capacities and the one with the highest interception capacities. For conidia, hedgerow height and side of the trap plants (with or without hedgerow between them and the source) were not significant, but low porosity of the hedgerow reduced the lesion density. On the contrary, for ascospore, the hedgerow effect was anisotropic; the trap plants on hedgerow side had less lesions. CONCLUSION:Our study is the first experimental proof of the effect of hedgerows on P. fijiensis dispersion, both on conidia and ascospore. We showed that hedgerow characteristics impact the capacity of interception of the hedgerow. © 2023 Society of Chemical Industry.

Automated, digitalized weather stations provide local, real time weather records which can orient improved management to address increasingly variable weather. In the past decade Banelino, an association of over 200 small organic banana growers, in Dominican Republic, has installed 8 weather stations to improve black leaf streak management. However, in a recent survey in Dominican Republic, 90% of small growers indicated that they do not access weather data from their local station. A FONTAGRO-financed project is underway to design and validate an app to convert weather data into indicators of potential growth and productivity of banana useful to growers. Equations drawing on long-established relationships between short-term banana performance and weather factors such as temperature, rainfall, solar radiation, and potential evapotranspiration were synthesized and adapted - leaf emission rate, duration of flowering to bunch harvest, potential bunch weight, nutrient demand to replace nutrients exported in bunches and water and irrigation demand. The app entitled degrees AHoRa from the symbol for temperature and first letters in Spanish for water, leaves and bunches receives daily updates from weather stations and calculates the indicators based either on varying fixed periods from 7 to 28 for water demand or variable periods based on accumulated growing degree days for leaf emission and bunch development. During a 4-month period small groups of pilot growers in close proximity to 5 different weather stations met biweekly to compare measured values from their farms with estimates of potential performance calculated based on real time weather data. Comparisons of calculated potentials with field data suggest a banana production performance gap from 10 to 70% below potential, greater for bunch weight than for leaf emission rate. Crop nutrition showed greater shortfalls than crop water demands. degrees AHoRa is a proof of concept for a crop-specific weather app, but also proved immediately useful to growers and field technicians. Approaches for more effective use and additional features to address resilience, efficiency and productivity are discussed.

The objective of this study was to understand the role of Cosmopolites sordidus in the dispersal of Fusarium oxysporum f. sp. cubense race 1 (Foc) and more specifically to determine whether C. sordidus is preferentially attracted to Foc‐contaminated banana plant material vs. Foc‐free material. The attraction of C. sordidus to healthy and Foc‐contaminated Gros Michel banana bulbs and pseudostems, as well as to pure cultures of Foc, was compared using four‐choice olfactometers. Males and females were studied separately. After storage in a dark room, weevils were placed in the central chamber of olfactometers. After 15 min, the orientation of each of the weevil was determined according to the food source located in each of the four peripheral chambers of the olfactometer. Overall, 560 olfactometer assays were carried out. Weevils were found to prefer Foc‐infected plant tissues. Weevil preference was not significantly affected by weevil sex. The attraction of C. sordidus to Foc‐contaminated plant material suggests that this insect could be important for the dissemination of Foc, especially in early stages of epidemics, when Foc‐infected plants are scarce.

Crop losses from pests threaten global food security and safety. In the last six decades, pest control using chemical pesticides has resulted in important yield gains per unit area, worldwide. However, the long-term sustainability of chemical pest control has been increasingly thrown into doubt due to the negative impact on human health, biodiversity, and the environment. Consequently, there is an urgent need to improve the science of crop protection in order to tackle the five key challenges of 21st century agriculture holistically: (i) maintaining or improving agricultural productivity, (ii) producing healthy food, (iii) reducing the negative impacts of agriculture on ecosystem and human health, (iv) ensuring the economic viability of farms, and (v) adapting agriculture to climate change. Agroecological Crop Protection (ACP) can be a powerful approach to address these challenges, as we demonstrate in this paper. ACP is the application of the principles of agroecology to crop protection in order to promote virtuous and sustainable changes in agriculture and food systems. ACP combines multiple approaches and disciplines including ecology, agroecology, and Integrated Pest Management. It promotes a crop protection system compatible with healthy agricultural and food systems, agroecological principles and the “one health” approach. We predict that ACP will meet the challenge of pesticide-free agriculture in the future. In this paper, we will first present the scientific, agricultural and social components of ACP. We will then analyze the research approaches, questions, methods and tools needed to adopt ACP. Finally, we suggest key mechanisms to facilitate the transition to ACP, which will ultimately provide sustainable food, feed, and fuel in a context of major global change.

Quantifying the effect of landscape composition on disease dynamics remains challenging because it depends on many factors. In this study, we used a hybrid process-based/statistical modeling approach to separate the effect of the landscape composition on the epidemiology of banana leaf streak disease (BLSD) from weather and fungicide effects. We parameterized our model with a 5-year dataset, including weekly measures of BLSD on 83 plots in Martinique. After estimating the intrinsic growth parameters of the stage evolution of the disease (SED), we evaluated the dynamic effect of five fungicides. Then, we added the intra- and inter-annual effect on disease dynamics using a generalized linear model. Finally, the whole model was used to assess the annual effect of the landscape on the SED for 11 plots. We evaluated the significance of the landscape composition (proportions of landscape elements in 200-, 500-, 800-, 1,000-m-radius buffer zones) on the landscape effect evaluated with the model. The percentage of hedgerows in a 200-m-radius buffer zone was negatively correlated to the landscape effect, i.e., it acted as a constraint against BLSD spreading and development. The proportion of managed-banana-plants in a 1,000-m-radius buffer zone was negatively correlated to the landscape effect, probably due to a mass effect of fungicide treatments. Inversely, the proportions of forest and the proportion of unmanaged-banana-plants, both in 1,000-m-radius buffer zones, were positively correlated with the landscape effect. Our study provides a holistic approach of the role biotic and abiotic factors play on the dynamics of BLSD.

BACKGROUND: Cosmopolites sordidus is one of the most damaging pests of banana worldwide. To date, most studies have addressed the control of this pest at the plot level, without considering the landscape scale, whereas between plots dispersion could be important. The aim of this study was to investigate the ability of C. sordidus to cross contrasted field interfaces. The 10 following interfaces were investigated: forests, hedgerows, field tracks, grassy areas, finely and coarsely tilled soil zones, ditches with and without water, vegetable gardening zones, and pheromone trap lines. Individually marked weevils were released on one side of the interface and recovered daily on the other side, allowing the estimation of the velocity and the crossing success of C. sordidus for each interface.RESULTS: Highest permeabilities (with a crossing success above 70%) were obtained for vegetable gardening zones, finely tilled soil zones, forests, and coarsely tilled soil zones. Intermediate permeabilities were measured for hedgerows, field tracks, grassy areas, and ditches without water. Only the line of pheromone traps and submerged ditches had a strong barrier effect on C. sordidus, with a crossing success below 12%. Wind strength, percentage of sky, and vegetation height were negatively correlated to the C. sordidus crossing success.CONCLUSION: Overall, our results showed that only ditches with water and lines of pheromone traps were efficient in stopping the dispersal of C. sordidus. The next step will be to conduct research to incorporate the use of these two interfaces at farm and landscape scale into integrated pest management strategies.(c) 2023 Society of Chemical Industry.

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 com-munities varied significantly with herbicide applications. More specifically, we found that native species rep-resented 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 potentially play a relevant role in soil biodiversity conservation.

Understanding the effect of ground types on foraging movements of ground-dwelling arthropods is a key step to managing their spatial distribution as required for successful conservation biological control. Indeed, fine movements at the centimeter scale can strongly influence the foraging ability of pest predators. However, because radio frequency identification or harmonic tracking techniques are not yet suitable for small species and video tracking focuses on uniform and light backgrounds, foraging movements have rarely been studied in relation to ground types. We present a method to track a ground-dwelling arthropod (the earwig Euborellia caraibea) at night, walking on two contrasted ground types: bare soil and soil partly covered with a stratum of banana plant residues allowing individuals to hide periodically. The tracking of individuals within these ground types was achieved by infrared light, tagging individuals, video treatments, and semi-automatic cleaning of trajectories. We tested different procedures to obtain segments with identical durations to quantify speeds and sinuosities. These procedures were characterized by the junction time gap between trajectory fragments, the rediscretization time of trajectories, and whether or not to use interpolation to fill in missing points in the trajectories. Earwigs exhibited significantly slower and more sinuous movements on soil with banana plant residues than on bare soil. Long time gaps for trajectory junction, extended rediscretization times, and interpolation were complementary means to integrate concealed movements in the trajectories. The highest slowdown in plant residues was detected when the procedure could account for longer periods under the residues. These results suggest that earwigs spent a significant amount of time concealed by the residues. Additionally, the residues strongly decreased the earwigs' movement. Since the technical solutions presented in this study are inexpensive, easy to set up, and replicate, they represent valuable contributions to the emerging field of video monitoring.

Understanding of ecological interactions is necessary for the application of biological control. Banana is the second most produced fruit worldwide and the banana weevil (Cosmopolites sordidus) is the most important pest of banana and plantain. Its biological control remains challenging because of the robustness and cryptic behaviour of the adult and the hidden development of larval stages. Researchers therefore tend to favour conservation biological control of this pest. The commonly used methods for measuring the effects of natural enemies on the regulation of this pest focus on invertebrates and may underestimate the role of vertebrates on biological control. Using cameras, we recorded the predation of sentinel adult weevils in banana plots in La Réunion island that differed in weevil infestation levels and in animal biodiversity. To facilitate image analysis, we used background subtraction to isolate moving parts of image sequences and thus detect predators and predation events. Our cameras recorded only vertebrates as predators of adult banana weevils. The most important predator appeared to be the Asian shrew (Suncus murinus), which was responsible for 67% of the predation events. Other predators included the house mouse (Mus musculus), the oriental garden lizard (Calotes versicolor), and the guttural toad (Sclerophrys gutturalis). The exact time of predation events were determined from the images metadata. It was thus possible to identify predator foraging periods that coincided with activity of adult weevils. Our results confirm that images provide useful information for biological and ecological studies. Along with other recent studies, our results suggest that the role of vertebrates in biological control may be underestimated. Based on these results, we advocate for several management implications such as the installation of hedges, grasslands, and ponds to favour these vertebrate predators of the banana weevil, possibly also favouring other vertebrate and invertebrate natural enemies.

The banana weevil Cosmopolites sordidus Germar is the most important pest of banana and plantain. In banana agroecosystems, cover cropping is a practice that prevents the use of herbicides and may provide natural habitats for generalist predators. Here, we assessed the effect of a cover crop, Paspalum notatum Flugge on the ant community, dermapterans and C. sordidus. In investigating the dumps of Pheidole jelskii Mayr colonies, we found that most of carcasses belonged to other ant species (> 96%) and very few (< 1%) belonged to C. sordidus. In plots with banana plants and with and without a cover crop, the occurrences of almost all ant species were negatively correlated with each other, but the occurrence of ants was not correlated with weevil abundance. However, we found a negative relationship between the abundances of dermapterans and C. sordidus, both of which were negatively related to presence of the cover crop. These results indicate that dermapterans are probably the main biological control agents of C. sordidus and that cover cropping may increase C. sordidus regulation.

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. This paper provides an overall orientation for the agroecological transition in tropical agriculture and also considers the socio-political context that underlies this transition.

With the dramatic increase of organic banana production worldwide, it is essential to be able to monitor compliance with organic specifications. While the detection of pesticide fraud is routinely controlled by detecting pesticide residues in organic bananas, the detection of fertilizer fraud is much more complex. We compared the delta C-13 and delta N-15 isotopic values of green bananas from organic and conventional farms at seven sites around the world. In our whole dataset, the delta N-15 values of banana fruits ranged between 1.25 and + 8.91%. In all sites, delta N-15 values of organic banana were significantly higher than conventional fruits (mean value of + 5.24% and + 2.342%, respectively). Conversely, the type of fertilization did not significantly alter delta C-13 values. Our results suggest that it is possible, upon arrival in importing countries, to differentiate bananas grown with synthetic fertilizer from those grown with organic fertilizer.