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Invasions by exotic species in areas already occupied by related species may lead to extinction or niche partitioning. Bactrocera dorsalis has invaded the Comoros archipelago in 2005 where other tephritids were already present. The host ranges of fruit flies in the Comoros were studied by conducting a seven-year survey on the three islands of the archipelago with a substantial sampling effort comprising 91 plant species from 37 families. The results showed that 45 fruit species in 16 families were infested by tephritid species. Eight fruit fly species were detected in the sampled fruits, but 78% of the individuals were identified as B. dorsalis, confirming its dominance and polyphagous status. More than ten years after its invasion, B. dorsalis has replaced Ceratitis capitata as the dominant fruit fly species on several species such as mango and citrus. The coexistence between B. dorsalis and C. capitata seems possible due to the capacity of the latter to exploit different niches, i.e. higher altitudinal ranges and a few host fruit species (among which, chillies and coffee berries) constituting a refuge niche. Information about coexistence between B. dorsalis and other tephritids is useful for the management and better estimates of invasion risks and associated biosecurity measures.

The fall armyworm, Spodoptera frugiperda (J.E. Smith) is native to the Americas and a major pest of corn and several other crops of economic importance. The species has characteristics that make it of particular concern as an invasive pest, including broad host range, long-distance migration behavior, and a propensity for field-evolved pesticide resistance. The discovery of fall armyworm in western Africa in 2016 was followed by what was apparently a remarkably rapid spread throughout sub-Saharan Africa by 2018, causing economic damage estimated in the tens of billions USD and threatening the food security of the continent. Understanding the history of the fall armyworm invasion of Africa and the genetic composition of the African populations is critical to assessing the risk posed to different crop types, the development of effective mitigation strategies, and to make Africa less vulnerable to future invasions of migratory moth pests. This paper tested and expanded on previous studies by combining data from 22 sub-Saharan nations during the period from 2016 to 2019. The results support initial descriptions of the fall armyworm invasion, including the near absence of the strain that prefers rice, millet, and pasture grasses, while providing additional evidence that the magnitude and extent of FAW natural migration on the continent is more limited than expected. The results also show that a second entry of fall armyworm likely occurred in western Africa from a source different than that of the original introduction. These findings indicate that western Africa continues to be at high risk of future introductions of FAW, which could complicate mitigation efforts.

International audience; The largest area of intact vegetation in the Mascarene's archipelago is found on Reunion Island, but the remaining natural areas are under threats. Biological invasions are one of the main threats to biodiversity loss on this island and globally worldwide. This study aimed to quantify invasion degree by alien plants species in Reunion Island. This work was possible thanks to a large partnership between researchers and managers. All existing spatial data on invasion pattern were combined and completed by expert knowledge to develop the first 250 x 250 m map of invasion degree at the island scale. To fill the gaps where no field survey data or expert knowledge was available, we used a Random Forest model using nine climatic, landscape and anthropogenic variables. This model also provides a preliminary assessment of drivers of invasion at Reunion Island. Results showed that 85% of the extant native vegetation was invaded in different proportions; 38% are slightly invaded, 26% moderately invaded and 22% very heavily invaded. Despite the high levels of invasion in some places, more than 50% of the extant vegetation is not invaded or slightly invaded. Most of the invaded areas are located in the lowland and in the leeward coast although alien plants invade all types of vegetation from the coast to the top of the island. These results highlight a clear increase in the distribution of alien species over time. This study constitutes a key first step for about the ongoing prioritisation of management interventions on Reunion Island.

Biological control can be an effective conservation strategy to manage invasive species when other conventional methods cannot be implemented. Estimating the benefits of biological control for the conservation of native biodiversity remains a challenging task. Following the introduction of a defoliating sawfly, Cibdela janthina, for biological control of invasive giant bramble, Rubus alceifolius, on Reunion Island (Mascarene Archipelago), we monitored the consequent change in R. alceifolius cover as well as species richness and cover of non-native species and native species within a set of patches along an altitudinal gradient in the National Park of Reunion Island. There was an increase in native species richness and cover together with a decrease in R. alceifolius cover, showing that biological control positively impacted the native plant communities. The effectiveness of C. janthina was influenced by the altitudinal range, the surface area of the patches and the location of each patch, i.e forest edge or forest matrix. We discuss the extent to which the use of biological control within an integrated approach can optimize benefits for biodiversity conservation in the short to medium term by selecting complementary and standardised protocols.

Better knowledge of food webs and related ecological processes is fundamental to understanding the functional role of biodiversity in ecosystems. This is particularly true for pest regulation by natural enemies in agroecosystems. However, it is generally difficult to decipher the impact of predators, as they often leave no direct evidence of their activity. Metabarcoding via high-throughput sequencing (HTS) offers new opportunities for unraveling trophic linkages between generalist predators and their prey, and ultimately identifying key ecological drivers of natural pest regulation. Here, this approach proved effective in deciphering the diet composition of key predatory arthropods (nine species., 27 prey taxa), insectivorous birds (one species, 13 prey taxa) and bats (one species, 103 prey taxa) sampled in a millet-based agroecosystem in Senegal. Such information makes it possible to identify the diet breadth and preferences of predators (e.g., mainly moths for bats), to design a qualitative trophic network, and to identify patterns of intraguild predation across arthropod predators, insectivorous vertebrates and parasitoids. Appropriateness and limitations of the proposed molecular-based approach for assessing the diet of crop pest predators and trophic linkages are discussed.

National audience

International audience; The number of invasive alien pest and pathogen species affecting ecosystem functioning, human health and economies has increased dramatically over the last decades. Discoveries of invasive pests and pathogens previously unknown to science or with unknown host associations yet damaging on novel hosts highlights the necessity of developing novel tools to predict their appearance in hitherto naive environments. The use of sentinel plant systems is a promising tool to improve the detection of pests and pathogens before introduction and to provide valuable information for the development of preventative measures to minimize economic or environmental impacts. Though sentinel plantings have been established and studied during the last decade, there still remains a great need for guidance on which tools and protocols to put into practice in order to make assessments accurate and reliable. The sampling and diagnostic protocols chosen should enable as much information as possible about potential damaging agents and species identification. Consistency and comparison of results are based on the adoption of common procedures for sampling design and sample processing. In this paper, we suggest harmonized procedures that should be used in sentinel planting surveys for effective sampling and identification of potential pests and pathogens. We also review the benefits and limitations of various diagnostic methods for early detection in sentinel systems, and the feasibility of the results obtained supporting National Plant Protection Organizations in pest and commodity risk analysis.

International audience; The genus Nasutitermes is among the most abundant wood-feeding Termitidae and an extremely diverse and heterogeneous group in terms of its biogeography and morphology. Despite the major role of several Nasutitermes species as structural pests, the phylogenetic status of this genus is still unclear, along with a confused taxonomy and species identification remaining difficult. The first aim of this review was thus to gather and discuss studies concerning the taxonomic status of the genus Nasutitermes in order to clarify this crucial point. Then, our goal was to gain new insights into the management of N. corniger, considered to be the most economically detrimental pest of this genus in South America and a Nasutitermes model species, while filtering available information concerning its biology through the prism of termite control, as well as critically examine the existing methods. We indeed strongly believe that increasing our knowledge of this species’ biological strategies is the key to progress in the challenging question of their sustainable management.

Xanthomonas vasicola pv. musacearum (Xvm) is a bacterial pathogen responsible for the economically important Xanthomonas wilt disease on banana and enset crops in Sub-Saharan Africa. Given that the symptoms are similar to those of other diseases, molecular diagnosis is essential to unambiguously identify this pathogen and distinguish it from closely related strains not pathogenic on these hosts. Currently, Xvm identification is based on polymerase chain reaction (PCR) with GspDm primers, targeting the gene encoding general secretory protein D. Experimental results and examination of genomic sequences revealed poor specificity of the GspDm PCR. Here, we present and validate five new Xvm-specific primers amplifying only Xvm strains.

Risques et bénéfices relatifs des alternatives aux produits phytopharmaceutiques comportant des néonicotinoïdes. Tome 1 – Rapport du groupe de travail Identification des alternatives aux usages autorisés des néonicotinoïdes

Risques et bénéfices relatifs des alternatives aux produits phytopharmaceutiques comportant des néonicotinoïdes. Tome 1 – Rapport du groupe de travail Identification des alternatives aux usages autorisés des néonicotinoïdes

Fil: Scarpeci, Telma. Universidad Nacional de Villa María; Argentina. Fil: Fissore, María Natalia. Universidad Nacional de Villa María; Argentina. Fil: Guillen, Joel Francis. Universidad Nacional de Villa María; Argentina. Fil: Allende, María José. Universidad Nacional de Villa María; Argentina. Fil: Bianchi, Francisco. Universidad Nacional de Villa María; Argentina. Fil: Palma, Leopoldo. Universidad Nacional de Villa María; Argentina.

Arboriculture must maintain acceptable fruit production levels while preserving natural resources. This duality can be analyzed with the concept of ecosystem service. We reviewed the literature on orchards to explain how ecological functions modified by agricultural practices provide six ecosystem services - fruit production, climate regulation, soil nitrogen availability, water regulation, pest and disease control, and pollination - and which indicators could describe them. The major points are, first, that orchards have a high potential of multiple services. They can sequester from 2.4 to 12.5 t C/ha/year. Their perennial character and multi-strata habitat, as well as the opportunity of creating diversified hedgerows and cover crops in alleys, may contribute to a high level of biodiversity and related services. Second, every service depends on many functions. Fruit yield, which could reach up to 140 t/ha in apple orchards, is increased by light interception, carbon allocation, and nitrogen and water uptake. Third, agricultural practices in orchards have a strong impact on ecosystem functions and, consequently, on ecosystem services. Overfertilization enhances nitrogen leaching, which reduces soil nitrogen availability for the plant and deteriorates the quality of drained water. Groundcover increases humification and reduces denitrification and runoff, thus enhancing soil nitrogen availability and water regulation. It also enhances biotic interactions responsible for pest control and pollination. Pruning may increase fruit quality trough a better carbon allocation but decreases pest control by fostering the dynamics of aphids. To study multiple ecosystem services in orchards, we suggest using models capable of simulating service profiles and their variation according to management scenarios. We then refer to the available literature to show that conflicts between provisioning and regulating services can be mitigated by agricultural practices. Improved knowledge of soil processes and carbon balance as well as new models that address multiple services are necessary to foster research on ecosystem service relationships in orchards.

International audience; Biological invasions exert multiple pervasive effects on ecosystems, potentially disrupting species interactions and global ecological processes. Our ability to successfully predict and manage the ecosystem-level impacts of biological invasions is strongly dependent on our capacity to empirically characterize complex biological interactions and their spatiotemporal dynamics. In this chapter, we argue that the comprehensive integration of multiple complementary tools within the explicit context of ecological networks is essential for providing mechanistic insight into invasion processes and their impact across organizational levels. We provide an overview of traditional (stable isotopes, populations genetics) and emerging (metabarcoding, citizen science) techniques and methods, and their practical implementation in the context of biological invasions. We also present several currently available models and machine-learning approaches that could be used for predicting novel or undocumented interactions, thus allowing a more robust and cost-effective forecast of network and ecosystem stability. Finally, we discuss the importance of methodological advancements on the emergence of scientific and societal challenges for investigating local and global species histories with several skill sets.

10. International Symposium on Modelling in Fruit Research and Orchard Management Location: Montpellier, FRANCE Date: JUN 05, 2015; Orchards represent relevant study systems for investigating the functional role of insectivorous birds as regulators of pest insect populations. In this context, we used a bioenergetics model (Wiens and Innis, 1974) to estimate the seasonal variation in daily insect consumption by natural populations of the great tit (Parus major) in organic apple orchards. This model allowed us to estimate the changes in both adult densities and energy requirements in a P. major population, using field-measured parameters such as the brood size, and the length of incubation. The calculation of insect consumption rate by birds was based on both the existing literature on great tit diets and the simulated energy requirement of a great tit population. The effect of a temperature increase on energy requirement has been quantified. This study opens the way to consider the functional role of birds in agricultural landscapes and how this role may translate to ecosystem services.

L'intensification de l'agriculture et la simplification biologique des agroécosystèmes conduit à une perte des fonctions écosystémiques tandis que le contrôle chimique des bioagresseurs (BAG) n'est pas durable. La diversification des agroécosystèmes est plébiscitée de manière croissante pour restaurer les interactions positives entre les plantes, telles que la régulation des BAG, au bénéfice des cultures. Mais la diversification bien qu'elle implique un partage des ressources ne doit pas se faire au détriment des rendements. Si la diversité végétale est le support de services de régulation des BAG, quel devrait être le niveau de ces régulations pour compenser les pertes de rendement liées à la compétition pour les ressources ? Quelles devraient-être la composition et la structure de la communauté de plantes pour optimiser de façon synergique les régulations de multiple BAG et la production ? J'ai d'abord quantifié par modélisation théorique les niveaux minimum de régulation des BAG requis pour compenser les pertes de rendement dues à la compétition, dans différents scénarios d'association et de ressources. J'ai ensuite réalisé une étude de terrain pour étudier les régulations écologiques de trois importants BAG du bananier dans un gradient de complexité végétale. Enfin, j'ai quantifié la part d'écart de rendement attribuable aux BAG et aux ressources. Je discute des interactions entre dégâts des BAG et compétition pour les ressources à l'échelle de la plante, des mécanismes de régulations écologiques des BAG du bananier et de la gestion de la végétation à l'échelle de la parcelle pour la régulation synergique des BAG et l'optimisation des rendements.

Xylomedes coronata (Marseul, 1883), a polyphagous xylophagous (Coleoptera, Bostrichidae). The native range of Xylomedes coronata (Marseul, 1883) (Coleoptera, Bostrichidae) expands from Morocco to Israel. This powderpost beetle has multiple hosts including Grapevine, Oleander, Argan tree, Pomegranate, Prunus, Citrus, and Olive tree. By completing its entire cycle in dead or living wood, it became a serious pest on Citrus in Morocco, and on Olive tree in Kabylie. The pest status varies along its native range and depends on several biotic factors, such as ecological disturbance, temperature and dryness. Other Mediterranean areas are threatened by global trade of timber and living trees., L'aire de répartition connue de Xylomedes coronata (Marseul, 1883) (Coleoptera, Bostrichidae) s''étend du Maroc à Israël. Il peut se développer dans les branches mortes ou vivantes d'essences variées, dont la Vigne, le Laurier-rose, l'Arganier, le Grenadier, divers Prunus, divers Agrumes et l'Olivier. Si les seuls dégâts sérieux sont cités sur Agrumes au Maroc et sur Olivier en Kabylie, il est susceptible de devenir un ravageur n''importe où dans son aire de répartition, surtout à la faveur des déséquilibres écologiques et d'épisodes chauds et secs. Le commerce d'arbres vivants ou de bois est susceptible de lui permettre de coloniser de nouveaux territoires méditerranéens., Aberlenc Henri-Pierre, Hamlaoui Mohand Salah. Xylomedes coronata (Marseul, 1883), un xylophage polyphage (Coleoptera, Bostrichidae). In: Bulletin de la Société entomologique de France, volume 116 (1),2011. pp. 29-33.

Le changement climatique modifie le comportement des bioagresseurs et leur distribution. Les risques que la pression phytosanitaire s'accroisse du fait des perturbations sur l'environnement et les agrosystèmes sont réels et inquiètent l'ensemble des acteurs agricoles, en particulier dans les pays tempérés où les introductions de nouveaux ravageurs, maladies et adventices sont légion. En Europe, la liste des introductions s'allonge et des phénomènes inquiétants apparaissent, avec une réelle menace sur la sécurité alimentaire. En milieu tropical, l'impact du changement climatique sur les populations de bioagresseurs et leurs ennemis naturels est plus difficile à appréhender et plus complexe. On observe des changements de statut de ravageurs, des introductions, des développements fulgurants de maladies ou d'insectes et une extension des aires de répartition. En s'appuyant sur des exemples d'insectes et de maladies d'importance économique sur quelques agrosystèmes tropicaux, nous discutons de l'impact au changement climatique sur ces bioagresseurs et proposons de nouvelles stratégies de protection agroécologique, en favorisant la conservation des services de régulation naturelle pour diminuer de façon durable les risques phytosanitaires.

Pour évaluer les fonctions nécessaires à la vie humaine, l'Analyse de Cycle de Vie (ACV) s'impose comme méthode d'évaluation consensuelle au niveau international. L'ACV permet d'évaluer l'ensemble des impacts environnementaux associés à la réalisation d'une fonction (produit, service) sur tout son cycle de vie. Appliquer l'ACV aux fonctions des systèmes agricoles reste un défi en lien avec la diversité des systèmes de production et de leurs fonctions, le double statut du sol qui appartient à la fois au système productif et à l'environnement, à la nature diffuse et variable des pollutions au champ et à l'importance des impacts régionaux comme l'eutrophisation et la consommation de ressources naturelles : eau et terre. Si les questions scientifiques de fond sont globalement les mêmes que l'on cherche à appliquer l'ACV à des systèmes de production animale en zone tempérée ou à des systèmes horticoles au sud, l'ampleur du défi est cependant bien plus vaste dans le second cas. Ces systèmes, souvent mal encadrés, parfois mal optimisés, toujours peu renseignés sont d'une grande diversité et leurs interactions avec l'environnement sont moins étudiées qu'en contexte tempéré. Dans le cadre de mes travaux sur les systèmes de production porcine, j'ai contribué à hiérarchiser les sources de variation des impacts qu'elles soient d'ordre technique (cahier des charge, qualité des pratiques) ou d'ordre méthodologique avec l'exploration de l'influence du devenir des nitrates dans les bassins versants sur les indicateurs eutrophisation et changement climatique. Pour réaliser ces évaluations, j'ai mis au point avec mes collègues des méthodes d'estimation des flux au champ et en atelier animal permettant une évaluation cohérente de systèmes contrastés. En production laitière en Nouvelle Zélande, j'ai notamment montré l'influence de l'intensification des systèmes sur la dégradation de leur éco-efficience et l'influence du mode de représentation de l'incertitude des paramètres sur le calcul de l'incertitude des résultats d'ACV par simulation Monte-Carlo. Sur les systèmes horticoles au sud, le premier enjeu est de caractériser proprement la diversité des systèmes et de produire leur inventaire avec peu ou pas de données préalables. Sur système pérenne, nous avons montré l'importance de prendre en compte toute la vie du verger et formulé des recommandations. Sur la tomate en zone urbaine au Bénin où aucune donnée n'était disponible, Aurélie Perrin a utilisé la typologie à dires d'expert pour échantillonner ses parcelles et produit un protocole de collecte de données d'inventaire fiables et représentatives de la fonction étudiée. Si l'usage de modèles mécanistes tels que STICS permet une exploration des sources de variations des émissions au champ et la prise en compte plus fine des conditions de sol, de climat et de pratiques, il appelle, pour être utile aux praticiens d'ACV, une simplification autour des paramètres principaux et une validation ultime par des données de flux mesurés. Pour l'avenir proche, j'ai construit mon projet scientifique autour de deux axes. Le premier est un projet collectif et pluridisciplinaire d'évaluation et d'amélioration de la performance des systèmes maraîchers en Afrique de l'Ouest où les déterminants de la performance des systèmes aux niveaux exploitation et parcelle seront explorés et une méthode d'estimation des flux de pesticides tenant compte des spécificités du contexte sera développée pour mieux évaluer d'éventuelles innovations sur la gestion des bio-agresseurs. Le second axe porté par Sandra Payen dans le cadre de sa thèse et d'un futur post-doctorat s'intéresse aux impacts liés à l'usage d'eau douce avec un travail sur la modélisation des flux de sels et d'eau à la parcelle et de leurs impacts associés tels que la salinisation.

International audience; A list of 91 species of thrips from Guadeloupe and Martinique, including 28 new records, is provided. New data on the ecology of some species and additional records of parasitoids and predators of thrips are given. A list of plants is provided on which populations of thrips have been observed, in some cases, with the presence of immature stages and/or thrips feeding damage.

The South American tomato leafminer, Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), is a major pest that has recently invaded Afro-Eurasia.[br/] Biological control, especially by Trichogramma parasitoids, is considered to be promising as a management tool for this pest. However, further development of Trichogramma-based biocontrol strategies would beneÞt from assessing the impact of released parasitoid offspring on the pest. Under laboratory conditions, we 1) compared the parasitismof five Trichogramma species-strains on the pest-plant system T. absoluta-tomato, and 2) assessed various biological traits of parasitoids, mass-reared on a factitious host (Ephestia kuehniella Zeller), when developing on T. absoluta. In addition, we evaluated the overall efÞciency of two specific Trichogramma species when released under greenhouse conditions in combination with a common natural enemy in tomato crop, the predator Macrolophus pygmaeus Rambur.[br/] Parasitoids emerging from T. absoluta on tomato showed lower parasitism rates and poor biological traits, for example, wing deformations, reduced longevity, when compared with the control reared on the factitious host. Under greenhouse conditions, the parasitoids that developed on T. absoluta after initial releases contributed little to biological control of T. absoluta, and parasitism tended to be lower when the predator was present. However, a slightly higher T. absoluta control level was achieved by combining the predator and release of the parasitoid Trichogramma achaeae Nagaraja and Nagarkatti.[br/] This study shows that Trichogramma parasitoids may not build up populations on the T. absolutaÐtomato system, but that Trichogramma parasitoids can be used in combination with M. pygmaeus to enhance biological control of the pest in tomato crops.

Chapter 7; The development of new methods and approaches for ensuring the sustainability of agriculture and ecosystem services is an important challenge that ecologists, agronomists, and theoreticians must address together. Enhancement of ecosystem services needs to be addressed at different scales and should include the interaction between farmland biodiversity and stakeholders (farmers, managers, policy makers, etc.) to optimize service delivery. Predictions require an understanding of the interactions between numerous management options and components of biodiversity. Here, we argue that interaction networks on a broad sense (from food webs to landscapes networks in which nodes could be species, trophic groups, fields or farms) can help address this high level of complexity. We examine how tools from mathematics and artificial intelligence, developed for network modelling and reasoning, could be useful for assessing and enhancing ecosystems services. In doing this we highlight the gaps that currently exist between our questions about ecosystem service provision and our ability to answer them with current modelling approaches. We illustrate the use of these tools with three case studies related to ‘pest regulation services’. These include food web approaches to assess animal pest regulation services and decisional models to address management strategies for diseases and weeds. Finally, we describe how different types of network models might operate at different scales of management. The future challenge for agroecologists will be to produce models of interactions and emergent ecosystem services, which are sufficiently quantified and validated. We suggest that network ecology is a nascent research topic that is developing a strong and unified empirical and theoretical foundation, which could serve as the central paradigm for a sustainable, intensive agriculture in the future.

A Madagascar, les larves et adultes terricoles de certaines espèces de Coléoptères Scarabeoidea causent d'importants dégâts au riz pluvial. Le traitement insecticide des semences assure une protection efficace, mais son impact environnemental soupçonné justifie des recherches pour s'en affranchir, notamment en systèmes de culture avec semis direct sur couverture végétale (SCV). Un système SCV, fondé sur une rotation riz pluvial-soja depuis 1998-1999, a ainsi été étudié de 2002 à 2007 sur deux sites des Hautes Terres. Sur cette rotation, on a trouvé, au bout de quatre ans (en 2002-2003), un effet positif du SCV (par rapport au labour) et du traitement de semences, en termes de réduction des attaques de ravageurs et de rendement du riz pluvial, sans effets négatifs du traitement des semences sur la biodiversité de la faune tellurique. Les quatre années suivantes, l'abondance de la macrofaune (phytophages comme saprophages/géophages et prédateurs), a augmenté, en particulier en SCV, sans que cela se traduise par des effets notables sur les rendements en 2005 et 2007. On a également étudié en laboratoire les préférences alimentaires des larves (" vers blancs ") de 3 espèces appartenant chacune à une famille de Scarabeoidea, et la variation du statut des larves de 7 espèces dans ces trois familles, en fonction du contenu du sol en matière organique. Bricoptis variolosa (Cetoniidae) et Hexodon unicolor (Dynastidae) se sont révélées être saprophages obligatoires, alors que Apicencya waterloti (Melolonthidae) s'est révélé rhizophage obligatoire, tandis que Heteroconus paradoxus et 3 autres espèces de Dynastidae ( Heteronychus plebeius, H. bituberculatus et H. arator rugifrons) se sont révélées rhizophages facultatifs. Outre les changements dans la composition faunistique tellurique induits par la gestion SCV, le changement de statut de certains vers blancs selon le statut organique du sol ouvre de nouvelles perspectives de gestion des agroécosystèmes rizicoles pluviaux.

International audience; Pest Risk Analyses (PRAs) are conducted worldwide to decide whether and how exotic plant pests should be regulated to prevent invasion. There is an increasing demand for science-based risk mapping in PRA. Spread plays a key role in determining the potential distribution of pests, but there is no suitable spread modelling tool available for pest risk analysts. Existing models are species specific, biologically and technically complex, and data hungry. Here we present a set of four simple and generic spread models that can be parameterised with limited data. Simulations with these models generate maps of the potential expansion of an invasive species at continental scale. The models have one to three biological parameters. They differ in whether they treat spatial processes implicitly or explicitly, and in whether they consider pest density or pest presence/absence only. The four models represent four complementary perspectives on the process of invasion and, because they have different initial conditions, they can be considered as alternative scenarios. All models take into account habitat distribution and climate. We present an application of each of the four models to the western corn rootworm, Diabrotica virgifera virgifera, using historic data on its spread in Europe. Further tests as proof of concept were conducted with a broad range of taxa (insects, nematodes, plants, and plant pathogens). Pest risk analysts, the intended model users, found the model outputs to be generally credible and useful. The estimation of parameters from data requires insights into population dynamics theory, and this requires guidance. If used appropriately, these generic spread models provide a transparent and objective tool for evaluating the potential spread of pests in PRAs. Further work is needed to validate models, build familiarity in the user community and create a database of species parameters to help realize their potential in PRA practice.

This paper provides reviews of the most commonly used methods to detect plant pests belonging to groups of invasive organisms with high economic relevance, including Coleoptera (bark beetles, flathead borers, leaf beetles, longhorn beetles, weevils), Diptera (cone and seed flies, fruit flies), Homoptera (aphids, leafhoppers and psyllids, whiteflies), Lepidoptera (moths and butterflies), Thysanoptera (thrips), bacteria (potato brown rot Ralstonia solanacearum) and fungi (pitch canker disease Gibberella circinata, brown rot disease Monilinia fructicola). Future perspectives in detection methods are discussed, with particular reference to the considerable increase in the volume, commodity type and origins of trade in plant material from third countries, the introduction of new crops, the continuous expansion of the EU with new border countries being added, and the impact of climate change affecting the geographical boundaries of pests and their vectors., Cet article passe en revue les méthodes les plus utilisées pour détecter les organismes nuisibles aux plantes appartenant à des groupes d'organismes envahissants qui ont une grande importance économique, comme les Coleoptera (scolytes, buprestides foreurs du bois, chrysomèles, longicornes, charançons), Diptera (mouches des cônes, mouches des fruits), Homoptera (pucerons, cicadelles et psylles, aleurodes), Lepidoptera (papillons), Thysanoptera (thrips), bactéries (pourriture brune de la pomme de terre Ralstonia solanacearum), champignons (chancre du pin Gibberella circinata, moniliose Monilinia fructicola). Les perspectives pour les méthodes de détection sont discutées, avec une référence particulière à l'importante augmentation dans les volumes, les types de marchandises et les origines de échanges commerciaux de matériel végétal à partir de pays tiers, l'introduction de nouvelles cultures, l'expansion continue de l'UE avec l'addition de nouveaux pays à ses frontières et l'impact du changement climatique affectant les frontières géographiques des organismes nuisibles et de leurs vecteurs., Oбзop мeтoдoв oбcлeдoвaний для выявлeния кapaнтинныx вpeдныx opгaнизмoв в Eвpoпeйcкoм coюзe B этoй cтaтьe paccмaтpивaютcя нaибoлee чacтo иcпoльзyeмыe мeтoды, пoзвoляющиe выявлять вpeдныe для pacтeний opгaнизмы, пpинaдлeжaщиe к paзличным гpyппaм инвaзивныx opгaнизмoв, имeющиe выcoкyю экoнoмичecкyю знaчимocть, тaкиe кaк жecткoкpылыe (жyки-кopoeды, злaтки, лиcтoeды, ycaчи, дoлгoнocики), двyкpылыe (шишкoвыe ceмeнныe и плoдoвыe мyxи), paвнoкpылыe (тли, цикaдки, лиcтoблoшки и бeлoкpылки), чeшyeкpылыe (бaбoчки), пyзыpeнoгиe (тpипcы), бaктepии (кapтoфeльнaя бypaя гниль Ralstonia solanacearum), гpибы (paк cocны Gibberella circinata, бypaя гниль Monilinia fructicola). Paccмaтpивaютcя пepcпeктивы paзвития мeтoдoв выявлeния, пpи этoм внимaниe зaocтpяeтcя нa знaчитeльнoм yвeличeнии oбъeмoв тopгoвли, нa paзнooбpaзии типoв тoвapoв и иcтoчникoв oтпpaвки pacтитeльныx мaтepиaлoв, пpoиcxoдящиx из тpeтьиx cтpaн, нa зaвoзe нoвыx кyльтyp, нa пpoдoлжaющeмcя pacшиpeнии EC c дoбaвлeниeм нoвыx cтpaн к eгo гpaницaм и нa вoздeйcтвии климaтичecкиx измeнeний, зaтpaгивaющиx гeoгpaфичecкиe гpaницы pacпpocтpaнeния вpeдныx opгaнизмoв и иx пepeнocчикoв.

International audience

International audience

National audience; Le projet se propose d'appliquer au cas de la mangue les concepts de la production fruitière intégrée, pris dans son acception la plus large, c'est-à-dire reposant sur la préservation de l'environnement, sur la viabilité économique des exploitations, mais aussi sur la qualité des fruits. Celle-ci est considérée comme un continuum, de la fleur au consommateur, impliquant une approche sur l'ensemble de la filière. Le projet mobilise un partenariat composé de la recherche, de l'expérimentation, du développement et de la formation agricoles. Il est structuré en quatre actions complémentaires et interactives visant à comprendre les pratiques et les stratégies des producteurs, à valider en milieu réel des modes de conduite innovants, à améliorer la qualité des mangues et leur durée de vie après récolte, et à former les acteurs de la filière. Des connaissances scientifiques, techniques et organisationnelles ont été acquises, de l'échelle du fruit à celle de la filière, apportant des éléments concrets pour faire évoluer cette dernière vers une démarche de production fruitière intégrée. Ces travaux se poursuivent à travers de nouveaux projets en partenariat, montrant ainsi l'effet multiplicateur apporté par cette initiative. (Résumé d'auteur)

Trade is important for economic development and growth; however, it is also the principal means of introducing invasive pests and disease vectors that can cause environmental damage and economic losses and pose a serious risk to biodiversity. Invasive pests and trade have created a two-way linkage, leading to perceptions that African countries are becoming a source of invasive pests in other countries via trade. What phytosanitary measures do African countries have to take therefore to reduce losses in economic and trade opportunities? Another important issue is the ability of African countries to reduce trade-related pest invasions from other countries and the impact of such invasions on African economies and the environment. Management strategies that can reduce the introduction of exotic pests, while not restricting the benefits of trade or causing protective trade barriers, are desirable. This paper reviews linkages between trade and invasive pests and the resulting effects on African agricultural exports, the economy, environment and biodiversity. Strategies and policies to deal with invasive pests, trade and trade barriers and protectionism are reviewed to assess how they may affect or can be used by African countries to address these problems.

International audience; Toxic plants have been used for years in agriculture to control major crop pests. However, the continuous exposure of targeted pests to toxins dramatically increases the rate of resistance evolution (Gassman et al. in Annu Rev Entomol 54:147–163, 2009a; Tabashnik et al. Nat Biotechnol 26:199–202, 2008). To prevent or delay resistance, non toxic host plants can be used as refuges. Our study considers spatial and temporal refuges that are respectively implemented concurrently or alternatively a toxic crop. A conceptual model based on impulsive differential equations is proposed to describe the dynamics of the susceptible and resistant pest populations over time. The mathematical study enlightens threshold values of the proportion of the spatial refuge and key parameters that should help to understand evolution of pest resistance to toxic crop.

ACIAR is funding research and extension activities in Indonesia to assist with the development of IPM strategies for Indonesian pests and diseases. Various borer species provide some of the greatest threats to Australia's sugarcane production system; research in Indonesia will lead to the development of Australian expertise in symptom recognition and an understanding of how to control these pests. Research is also being conducted into the various forms of sugarcane mosaic present not just in Indonesia but elsewhere in South East Asia. Incursion management plans will be updated as control measures are further refined during the course of these studies. General surveys conducted in over 930 individual Indonesian sugarcane crops highlighted the incidence of pests and diseases of significance. Further research is being conducted into the vectors transmitting mosaic and yield losses associated with this disease. Research is also being conducted into biological control measures for borers (Chilo or Scirpophaga species) using a range of either egg, larval or pupal parasitoids. Extension activities include demonstration plots, champion farmers, an Indonesian pest and disease field guide and various training days for farmers and factory field staff. This paper describes the work being undertaken and some of the latest outputs.

La recherche a été menée sur plusieurs fronts ces dernières campagnes pour la lutte durable contre les bioagresseurs du riz pluvial. Elle s'est orientée vers l'exploitation de la biodiversité des plantes et la recherche de systèmes de culture pour gérer les " vers blancs " ou " scarabées noirs " (Coleoptera, Scarabaeidae), les foreurs de tiges, la pyriculariose et le striga. Les résultats des essais réalisés avec le projet BVlac sur l'utilisation du champignon entomopathogène Metarhizium anisopliae ainsi que les résultats des essais menés avec l'ONG Tafa sur la lutte contre le striga dans différents systèmes de culture seront présentés par ailleurs. Nous rapporterons ici les recherchés menées sur la gestion des vers blancs dans des systèmes exploitant la biodiversité végétale, sur les tests en laboratoire de l'effet d'extraits végétaux, sur l'étude au laboratoire de l'efficacité de molécules issues de plantes à propriétés répulsives, insecticides ou insectifuges sur les foreurs de tiges, et sur l'étude des conditions agronomiques permettant d'améliorer la résistance du riz à la pyriculariose.

Esta visita, inicialmente programada para el inicio de octubre, fue postergada por parte de Palesema, debido a unos problemas inherentes a la zona de San Lorenzo. El problema principal desde varios meses es la mortalidad por "Pudrición de Cogollo". Por tal motivo, la compañía decidió sembrar a partir del 2008, solamente híbridos y unos lotes de un material guineensis (C07**) que dio buenos resultados en el Oriente ecuatoriano (PDE) en la primera generación (siembra 1981), y que al momento se presenta con un grado de incidencia inferior en Palesema. Sin embargo, la presencia de este disturbio debe incitar todavía más a cambiar la estrategia de la compañia con respecto a: - la política de eliminación de las parcelas afectadas, - la política de limpieza de drenajes, - la polinización asistida, - la fertilización (tes interesante o no fertilizar con dosis altas, parcelas que tienen todavía al máximo solamente 4 años de vida útil, sabiendo que el efecto de la fertilización se va a notar dentro de 2 años?). - la relación futura entre la PC en parcelas de híbridos y la PSC en vivero. Otro aspecto fitosanitario, es el estado actual del sistema foliar con los ataques de stenoma, opsiphanes y struthocelis. No soy experto en entomologia, pero me parece que es urgente organizar una vuelta de tratamiento químico con avioneta. Fuera de estos dos problemas fitosanitario, es necesario actualizar de manera periódica los antivirus, ya que al parecer todos los computadores de la plantacion están infestados de virus. De no ser posible hay que poner claves de accesos a los computadores. La eficiencia de la polinización asistida debe ser mejorada, con la contratación de un técnico, la búsqueda de una fuente segura de polen, la implementación de controles tanto al nivel de campo que de fabrica para detectar fallas en la formación de racimos. Todo eso antes de la entrada en producción de los programas híbridos. El mantenimiento, es globalmente satisfactorio. Sin embargo, quedan zonas con palmas atrasadas para recuperar, hay que vigilar la poda, y hacer un esfuerzo, para mantener limpios los drenajes y los linderos. La calidad de la cosecha puede ser mejorada sobre todo en las zonas 2 y 3, donde se ven perdidas en pepas sueltas al pie de los arboles, en las axilas, en las caminatas y en los puestos de recepción. Por cuanto a la preparación de terreno, hay que mencionar el atraso en la siembra de la planta de cobertura (falta por sembrar una parte de las parcelas del cultivo 2009). Si no se quiere sembrar mucuna, en parcelas, por lo menos se la podría instalar en los linderos para facilitar el mantenimiento. En renovación, es de contemplar el uso de una rastra de discos (una esta en el taller, sin uso) de manera a nivelar el suelo. Con respecto a los viveros, hay que tener un particular cuidado a los ataques de ácaros y cochinillas. Las observaciones climatologicas que figuran en los informes mensuales serán fiables, siempre y cuando están llevadas correctamente es decir que no faltan lecturas en particular los feriados. Se precisa tener siempre actualizadas los datos de vientos, entre otras cosas. Con respecto a la fertilización mineral, globalmente al aspecto de las hojas no deja aparecer sintomas de deficiencia. Los responsables de la plantacion decidieron: - reforzar la fertilización propuesta para los cultivos de híbridos, - reducir al máximo en 2008/09, la fertilización de los cultivos "adultos" de guineensis. Tal vez, seria mejor no descuidar de los cultivos adultos, ya que si no reciben fertilizantes, eso va impactar sobre producción futura y también se podría confundir una deficiencia de nitrogena con un ataque precoz de PC. En anexos 4, están las recomendaciones de Fertilización para el periodo 2009/2010.

Cotton cultivation, often highlighted for its excessive consumption of plant protection products, is taken as a model to illustrate the development of the ideas and practices of crop protection over the last 50 years. Cotton is grown in 69 countries on 30–35 million hectares and the production exceeded 20 million tones of lint in recent years. Despite the continual improvement in the performance of chemical control strategies, harvest losses remain very high, of about 30%. The largest consumer of pesticides in the world, the cotton production system has the advantage of having been an experimental model for many crop protection programmes under various agronomic conditions and in the presence of diverse pest complexes. Without attempting an exhaustive bibliography, this review explores how and why the ideas underlying crop protection have significantly evolved since the advent of synthetic pesticides. After a spectacular demonstration of yield growth through the application of chemical control, cotton production was rapidly confronted by the secondary effects of this control. These included the appearance of evolved insecticide resistance and the appearance of new damage caused by pests considered up to then as of only secondary importance. In extreme cases, the economic viability of the production systems themselves have been compromised following increases in the application rate and frequency of insecticidal treatments. In general, harvest losses have remained high despite the constantly improving technical performance of pest control chemicals. Two models of the future of crop protection can be drawn: total pest management which involves the eradication of pests, and integrated pest management (IPM), which aims at the management of pest populations below economic thresholds by a mixture of chemical control and a suite of alternative control measures. The first method, total pest management is limited in agricultural systems to particular cases in which the pest in question has no significant alternate hosts in the vicinity of the crop system. On the other hand, the application of IPM is constrained both by the difficulties in exploiting the concept of an ‘intervention threshold’ and by the limitations of many of the specific non-chemical techniques proposed, but does have the advantage of taking into consideration the full pest complex in a cropping system. In practice, it has been a calendar schedule, largely of insecticidal treatments, established on the basis of earlier local observations which has been most widely adopted by growers. This strategy has produced significant improvements in production in the cotton producing countries of francophone Africa and elsewhere. This has led to area-wide integrated pest management which takes into account the potential for natural factors to regulate populations in a specific region. In cotton production, biological control by introduction and acclimation of beneficial arthropods has not been notably successful because of the difficulty of developing a suite of beneficial organisms capable of responding effectively to the diversity of pests in the system, the annual nature of the crop, and the disrupting effects of chemical control measures directed against the remaining pests. Only inundative biological control has had significant success and then in particular cases where the pressure of chemical insecticides has been reduced. More benefit is to be obtained from the active conservation of the indigenous fauna of beneficial organisms. In spite of an increased general environmental awareness, in practice it has been the growth of evolved resistance to pesticides which has had the dominant role in constraining the growers to a more rational use of control strategies. These can be illustrated by the development of window strategies for control measures across the growing season, initially in Australia. The reduction in chemical control treatments made possible by the efficacy of genetically modified cotton has shown the positive role that indigenous natural enemies can play. At the same time, however, there has been a growth in the importance of pest species which are unaffected by Bt toxins. For example, the sucking pests are progressively coming to displace the vegetative and fruit feeding caterpillars as key pests of Bt cotton. Taking into account the spatio-temporal dimension of natural population regulatory factors has led to changes in agricultural practices and production systems. In cotton, for example, production systems maintaining permanent ground cover, are having increasing success. Intercropping and trap cropping have been favourable to the maintenance of beneficial arthropod complexes and unfavourable to the growth of pest populations. This new design context for crop protection in general and for cotton in particular, in applying the principles of agroecology, moves towards the concept of a truly sustainable agriculture. This implies a change of strategy towards a total systems approach to sustainable pest management, characterised by a movement from a paradigm of pest control field-by-field, through farm-by-farm and agroecosystem-by-agroecosystem, to a landscape by landscape approach.