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Chemical control of disease vectoring mosquitoes Aedes albopictus and Aedes aegypti is costly, unsustainable, and increasingly ineffective due to the spread of insecticide resistance. The Sterile Insect Technique is a valuable alternative but is limited by slow, error-prone, and wasteful sex-separation methods. Here, we present four Genetic Sexing Strains (two for each Aedes species) based on fluorescence markers linked to the m and M sex loci, allowing for the isolation of transgenic males. Furthermore, we demonstrate how combining these sexing strains enables the production of non-transgenic males. In a mass-rearing facility, 100,000 first instar male larvae could be sorted in under 1.5 h with an estimated 0.01–0.1% female contamination on a single machine. Cost-efficiency analyses revealed that using these strains could result in important savings while setting up and running a mass-rearing facility. Altogether, these Genetic Sexing Strains should enable a major upscaling in control programmes against these important vectors.

Balancing process efficiency and adult sterile male biological quality is one of the challenges in the success of the sterile insect technique (SIT) against insect pest populations. For the SIT against mosquitoes, many stress factors need to be taken into consideration when producing sterile males that require high biological quality to remain competitive once released in the field. Pressures of mass rearing, sex sorting, irradiation treatments, packing, transport and release including handling procedures for each step, add to the overall stress budget of the sterile male post-release. Optimizing the irradiation step to achieve maximum sterility while keeping off-target somatic damage to a minimum can significantly improve male mating competitiveness. It is therefore worth examining various protocols that have been found to be effective in other insect species, such as dose fractionation. A fully sterilizing dose of 70 Gy was administered to Aedes aegypti males as one acute dose or fractionated into either two equal doses of 35 Gy, or one low dose of 10 Gy followed by a second dose of 60 Gy. The two doses were separated by either 1- or 2-day intervals. Longevity, flight ability, and mating competitiveness tests were performed to identify beneficial effects of the various treatments. Positive effects of fractionating dose were seen in terms of male longevity and mating competitiveness. Although applying split doses generally improved male quality parameters, the benefits may not outweigh the added labor in SIT programmes for the management of mosquito vectors.

Compensation and overcompensation under field conditions are confirmed in Aedes mosquitoes recently by Evans et al.: equal or increased densities of emerging adults may thus result from reduced larval densities. Here the consequences when applying the sterile insect technique and provide recommendations to avoid counterproductive effects are discussed.

Background: Over the past decades, several viral diseases transmitted by Aedes mosquitoes—dengue, chikungunya, Zika—have spread outside of tropical areas. To limit the transmission of these viruses and preserve human health, the use of mosquito traps has been developed as a complement or alternative to other vector control techniques. The objective of this work was to perform a systematic review of the existing scientific literature to assess the efficacy of interventions based on adult mosquito trap to control Aedes population densities and the diseases they transmit worldwide. Methods and findings: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic review was conducted using the PubMed and Scopus databases. Among the 19 selected papers, lethal ovitraps were used in 16 studies, host-seeking female traps in 3 studies. Furthermore, 16 studies focused on the control of Ae. aegypti. Our review showed great heterogeneity in the indicators used to assess trap efficacy: e.g., the number of host-seeking females, the number of gravid females, the proportion of positive containers, the viral infection rate in female mosquitoes or serological studies in residents. Regardless of the type of studied traps, the results of various studies support the efficacy of mass trapping in combination with classical integrated vector control in reducing Aedes density. More studies with standardized methodology, and indicators are urgently needed to provide more accurate estimates of their efficacy. Conclusions: This review highlights gaps in the demonstration of the efficacy of mass trapping of mosquitoes in reducing viral transmission and disease. Thus, further large-scale cluster randomized controlled trials conducted in endemic areas and including epidemiological outcomes are needed to establish scientific evidence for the reduction of viral transmission risk by mass trapping targeting gravid and/or host-seeking female mosqu

Hypothenemus hampei (Ferrari) ou scolyte des fruits du caféier est le ravageur le plus redoutable pour cette culture. Il est actuellement présent dans la presque totalité des régions productrices de café dans le monde, le dernier grand territoire atteint étant la Papouasie Nouvelle Guinée, où il a été officiellement signalé en 2017. Le scolyte a également été découvert dans deux départements français d'Outre-mer d'où il était absent jusqu'alors, la Martinique en 2012, puis tout récemment la Guadeloupe en début d'année 2021. Il représente pour cette région une menace pour l'existence même de la caféiculture qui fait partie de son patrimoine historique. Le scolyte a été détecté à la périphérie puis au coeur de la zone où le caféier est traditionnellement cultivé. Les mesures prises par les autorités locales pour freiner la dispersion du ravageur donnent déjà suite à des recommandations en matière de lutte qui seront adaptées à la situation agronomique et économique de la filière café.

La présence envahissante des moustiques et de leurs agents pathogènes modifie notre quotidien et questionne nos habitudes de vie. Les moustiques contribuent à des milliers de décès chaque année dans le monde en transmettant différents parasites et virus, responsables de maladies aux noms bien connus : paludisme, dengue, zika, chikungunya, etc. Ce qui est moins connu, en revanche, c'est que les moustiques participent aussi à l'équilibre des écosystèmes comme source de nourriture pour de nombreuses espèces et qu'ils contribuent à la pollinisation de végétaux. Leur grande diversité morphologique, biologique, écologique et génétique doit être bien appréhendée avant d'envisager des solutions pour mieux contrôler leur diffusion et leur pullulation, et maîtriser ainsi la transmission des agents pathogènes. Devant cette menace en rapide évolution, des stratégies innovantes et concertées de lutte contre ces insectes se déploient dans de nombreux pays. S'adressant à un public large, mais également aux étudiants et à leurs enseignants, ce livre, illustré de nombreux exemples, est une synthèse des connaissances sur les moustiques et sur les méthodes de lutte actuelles.

Competent arbovirus vectors are found in the culicid mosquito fauna of south-west Indian Ocean (SWIO) islands. In La Reunion, Aedes albopictus and Aedes aegypti mosquitoes are known vectors of dengue and chikungunya viruses. Culex quinquefasciatus is a potential vector of Rift Valley fever and West Nile viruses. To prepare a vector-control field trial against Ae. aegypti, this study aimed at identifying the best trapping strategy to catch adult Ae. aegypti, using BG-Sentinel traps (Biogents, Germany). It was implemented in two sites in southern La Reunion. Catches of Ae. albopictus and Cx. quinquefasciatus mosquitoes were also recorded. A Latin square design was used to estimate the detection probability and the apparent daily density—according to the BG-Sentinel trapping strategy: none, carbon dioxide (CO2), a commercial attractant—BG-Lure (Biogents, Germany), or both. The use of CO2 alone was associated with a higher detection probability for Ae. aegypti and Cx. quinquefasciatus mosquitoes, as well as a large increase in their apparent density. Traps with BG-Lure—alone or in combination with CO2, did not improve the detection probability of Ae. aegypti and Cx. quinquefasciatus mosquitoes. The same result was found for male Ae. albopictus. For females, baiting BG-Sentinel traps with CO2 or BG-Lure had no significant effect. The same apparent densities were found for Ae. aegypti and Ae. albopictus mosquitoes in both study sites—where Ae. aegypti mosquitoes were found at very low densities during previous surveys.

Several dengue epidemics recently occurred in La Reunion, an island harboring two dengue viruses (DVs) vectors: Aedes albopictus, and Ae. aegypti, the former being the main local DV vector. Aedes aegypti shows a peculiar ecology, compared to other tropical populations of the same species. This study aimed to provide researchers and public-health users with locally validated oviposition traps (ovitraps) to monitor Aedes populations. A field experiment was performed in Saint-Joseph to assess the effect of different settings on the detection probability and apparent density of Aedes mosquitoes. Black plastic ovitraps were identified as the best choice. Vacoa trees (Pandanus utilis) were the only observed breeding sites for Ae. aegypti, shared with Ae. albopictus. They were the experimental units in a Latin square design with three factors: trap position in the trees (ground vs canopy), oviposition surface in the trap (blotting paper vs. vacoa leaf), and addition of organic matter to the trap water. The latter factor was found unimportant. On the ground, Ae. aegypti eggs were only found with vacoa leaves as the oviposition surface. Their detection and apparent density increased when ovitraps were located in the tree canopy. The main factor for Ae. albopictus was the oviposition surface, with a preference for blotting paper. In all trap settings, their detection was close to 100%. Larval survival was lower for a high egg density, combined with blotting paper as the oviposition surface. When monitoring mixed Aedes populations in La Reunion, we recommend using black plastic ovitraps, placed at 1.50-to-2.00-m high in vacoa trees, with vacoa leaves as the oviposition surface.

Background: The use of long-lasting insecticide-treated nets (LLINs) is one of the main malaria prevention method promoted by the World Health Organization (WHO) in Côte d'Ivoire. LLIN-coverage has reached 95% since 2015 and nearly 16 million LLINs were distributed in 2017. Despite these efforts, malaria incidence at the national level remains high (120‰ in 2012 to 164‰ in 2017) although this could be partly explained by increased screening efforts. This study aimed at determining what preventative measures were used against mosquito bites, as well as LLIN maintenance practices used by the inhabitants of the city of Bouaké, capital city of the Gbêkê region with a malaria incidence of 257‰ in 2017. Methods: A descriptive qualitative investigation took place in Bouaké, in four neighbourhoods that were selected through purposive sampling based on their social composition. Data were collected using an interview guide based on convenience sampling. Results: The results of the study reveal that LLINs are the most reported used malaria prevention measure (66.4%). Environmental health (28.8%) came second in their declarations, smoke coils (23.5%) third and aerosol cans (18.8%) last. The percentage of respondents who answered that they had slept under an LLIN the previous night was 53%. 57.7% reported that they wash their LLINs, 12.1% that they do not wash them, and 4% that they replace dirty LLINs with new ones. The LLINs washing methods described by the respondents did not comply with the WHO recommendations and there was no mention of LLINs repairs. Conclusion: Despite mass distributions of LLINs in Côte d'Ivoire, this key malaria control tool remains under-used by the population. Regarding LLIN maintenance, more than half of the population reports that they wash their nets while not complying with recommended practices or repairing them.

Aedes albopictus is a major vector of arboviruses. Better understanding of its sex determination is crucial for developing mosquito control tools, especially genetic sexing strains. In Aedes aegypti, Nix is the primary gene responsible for masculinization and Nix-expressing genetic females develop into fertile, albeit flightless, males. In Ae. albopictus, Nix has also been implicated in masculinization but its role remains to be further characterized. In this work, we establish Ae. albopictus transgenic lines ectopically expressing Nix. Several are composed exclusively of genetic females, with transgenic individuals being phenotypic and functional males due to the expression of the Nix transgene. Their reproductive fitness is marginally impaired, while their flight performance is similar to controls. Overall, our results show that Nix is sufficient for full masculinization in Ae. albopictus. Moreover, the transgene construct contains a fluorescence marker allowing efficient automated sex sorting. Consequently, such strains constitute valuable sexing strains for genetic control.

The sterile insect technique is a promising environmentally friendly method for mosquito control. This technique involves releasing laboratory-produced sterile males into a target field site, and its effectiveness may be affected by the extent of adult mosquito predation. Sterile males undergo several treatments. Therefore, it is vital to understand which treatments are essential in minimizing risks to predation once released. The present study investigates the predation propensity of four mantis species (Phyllocrania paradoxa, Hymenopus coronatus, Blepharopsis mendica, Deroplatys desiccata) and two gecko species (Phelsuma standingi, P. laticauda) on adult Aedes aegypti, Ae. albopictus and Anopheles arabiensis mosquitoes in a laboratory setting. First, any inherent predation preferences regarding mosquito species and sex were evaluated. Subsequently, the effects of chilling, marking, and irradiation, on predation rates were assessed. The selected predators effectively preyed on all mosquito species regardless of the treatment. Predation propensity varied over days for the same individuals and between predator individuals. Overall, there was no impact of laboratory treatments of sterile males on the relative risk of predation by the test predators, unless purposely exposed to double the required sterilizing irradiation dose. Further investigations on standardized predation trials may lead to additional quality control tools for irradiated mosquitoes.

Ecological phenomena operate at different spatial scales and are not uniform across landscapes or through time. One ecological theory that attempts to account for scaling and spatiotemporal variances is hierarchical patch dynamics. It introduces a hierarchical patch network with smaller spatiotemporal scales being nested within larger scales. However, few studies have modeled its presence within animal population dynamics. Locusts are an excellent model for investigating the spatiotemporal hierarchy of animal population dynamics, due to their high migratory capacity, large geographic ranges that extend across widely differing environments, and available long-term data on distributions. Here, we investigated the influence of preceding vegetation growth on desert locust Schistocerca gregaria and Australian plague locust Chortoicetes terminifera outbreaks on three spatial levels (species range > geographic region > land unit) and between seasons. Both species are dryland herbivores with population dynamics linked to habitat productivity pulses after rain. We used NDVI data (MODIS imagery) as a measure of vegetation growth in hierarchical generalized additive models at different scales. Locust outbreaks were either preceded by vegetation growth between 78 and 32 days (Australian plague locusts) or 32 and 20 days before (desert locust) the observation. Although prior vegetation growth characterized outbreaks of both species, the temporal pattern of NDVI differed between spatiotemporal levels. All model selection criteria selected for a similar spatial hierarchy for both species: geographic region > land unit which supports the hierarchical patch dynamics paradigm. Further, it illuminates important timing differences between geographic regions and land units for preceding vegetation growth and locust outbreaks which can help locust managers identify when and where outbreaks occur. By acknowledging the spatiotemporal patterning of locust abundance, we account for heterogen

Background: The use of long-lasting insecticide-treated nets (LLINs) is one of the main malaria prevention method promoted by the World Health Organization (WHO) in Côte d'Ivoire. LLIN-coverage has reached 95% since 2015 and nearly 16 million LLINs were distributed in 2017. Despite these efforts, malaria incidence at the national level remains high (120‰ in 2012 to 164‰ in 2017) although this could be partly explained by increased screening efforts. This study aimed at determining what preventative measures were used against mosquito bites, as well as LLIN maintenance practices used by the inhabitants of the city of Bouaké, capital city of the Gbêkê region with a malaria incidence of 257‰ in 2017. Methods: A descriptive qualitative investigation took place in Bouaké, in four neighbourhoods that were selected through purposive sampling based on their social composition. Data were collected using an interview guide based on convenience sampling. Results: The results of the study reveal that LLINs are the most reported used malaria prevention measure (66.4%). Environmental health (28.8%) came second in their declarations, smoke coils (23.5%) third and aerosol cans (18.8%) last. The percentage of respondents who answered that they had slept under an LLIN the previous night was 53%. 57.7% reported that they wash their LLINs, 12.1% that they do not wash them, and 4% that they replace dirty LLINs with new ones. The LLINs washing methods described by the respondents did not comply with the WHO recommendations and there was no mention of LLINs repairs. Conclusion: Despite mass distributions of LLINs in Côte d'Ivoire, this key malaria control tool remains under-used by the population. Regarding LLIN maintenance, more than half of the population reports that they wash their nets while not complying with recommended practices or repairing them.

Ecological phenomena operate at different spatial scales and are not uniform across landscapes or through time. One ecological theory that attempts to account for scaling and spatiotemporal variances is hierarchical patch dynamics. It introduces a hierarchical patch network with smaller spatiotemporal scales being nested within larger scales. However, few studies have modeled its presence within animal population dynamics. Locusts are an excellent model for investigating the spatiotemporal hierarchy of animal population dynamics, due to their high migratory capacity, large geographic ranges that extend across widely differing environments, and available long-term data on distributions. Here, we investigated the influence of preceding vegetation growth on desert locust Schistocerca gregaria and Australian plague locust Chortoicetes terminifera outbreaks on three spatial levels (species range > geographic region > land unit) and between seasons. Both species are dryland herbivores with population dynamics linked to habitat productivity pulses after rain. We used NDVI data (MODIS imagery) as a measure of vegetation growth in hierarchical generalized additive models at different scales. Locust outbreaks were either preceded by vegetation growth between 78 and 32 days (Australian plague locusts) or 32 and 20 days before (desert locust) the observation. Although prior vegetation growth characterized outbreaks of both species, the temporal pattern of NDVI differed between spatiotemporal levels. All model selection criteria selected for a similar spatial hierarchy for both species: geographic region > land unit which supports the hierarchical patch dynamics paradigm. Further, it illuminates important timing differences between geographic regions and land units for preceding vegetation growth and locust outbreaks which can help locust managers identify when and where outbreaks occur. By acknowledging the spatiotemporal patterning of locust abundance, we account for heterogen

Aedes albopictus is a major vector of arboviruses. Better understanding of its sex determination is crucial for developing mosquito control tools, especially genetic sexing strains. In Aedes aegypti, Nix is the primary gene responsible for masculinization and Nix-expressing genetic females develop into fertile, albeit flightless, males. In Ae. albopictus, Nix has also been implicated in masculinization but its role remains to be further characterized. In this work, we establish Ae. albopictus transgenic lines ectopically expressing Nix. Several are composed exclusively of genetic females, with transgenic individuals being phenotypic and functional males due to the expression of the Nix transgene. Their reproductive fitness is marginally impaired, while their flight performance is similar to controls. Overall, our results show that Nix is sufficient for full masculinization in Ae. albopictus. Moreover, the transgene construct contains a fluorescence marker allowing efficient automated sex sorting. Consequently, such strains constitute valuable sexing strains for genetic control.

The sterile insect technique is a promising environmentally friendly method for mosquito control. This technique involves releasing laboratory-produced sterile males into a target field site, and its effectiveness may be affected by the extent of adult mosquito predation. Sterile males undergo several treatments. Therefore, it is vital to understand which treatments are essential in minimizing risks to predation once released. The present study investigates the predation propensity of four mantis species (Phyllocrania paradoxa, Hymenopus coronatus, Blepharopsis mendica, Deroplatys desiccata) and two gecko species (Phelsuma standingi, P. laticauda) on adult Aedes aegypti, Ae. albopictus and Anopheles arabiensis mosquitoes in a laboratory setting. First, any inherent predation preferences regarding mosquito species and sex were evaluated. Subsequently, the effects of chilling, marking, and irradiation, on predation rates were assessed. The selected predators effectively preyed on all mosquito species regardless of the treatment. Predation propensity varied over days for the same individuals and between predator individuals. Overall, there was no impact of laboratory treatments of sterile males on the relative risk of predation by the test predators, unless purposely exposed to double the required sterilizing irradiation dose. Further investigations on standardized predation trials may lead to additional quality control tools for irradiated mosquitoes.

Kairomones are chemical signals that mediate interspecific interactions beneficial to organisms that detect the cues. These attractants can be individual compounds or mixtures of herbivore-induced plant volatiles (HIPVs) or herbivore chemicals such as pheromones, i.e., chemicals mediating intraspecific communication between herbivores. Natural enemies eavesdrop on kairomones during their foraging behaviour, i.e., location of oviposition sites and feeding resources in nature. Kairomone mixtures are likely to elicit stronger olfactory responses in natural enemies than single kairomones. Kairomone-based lures are used to enhance biological control strategies via the attraction and retention of natural enemies to reduce insect pest populations and crop damage in an environmentally friendly way. In this review, we focus on ways to improve the efficiency of kairomone use in crop fields. First, we highlight kairomone sources in tri-trophic systems and discuss how these attractants are used by natural enemies searching for hosts or prey. Then we summarise examples of field application of kairomones (pheromones vs. HIPVs) in recruiting natural enemies. We highlight the need for future field studies to focus on the application of kairomone blends rather than single kairomones which currently dominate the literature on field attractants for natural enemies. We further discuss ways for improving kairomone use through attract and reward technique, olfactory associative learning, and optimisation of kairomone lure formulations. Finally, we discuss why the effectiveness of kairomone use for enhancing biological control strategies should move from demonstration of increase in the number of attracted natural enemies, to reducing pest populations and crop damage below economic threshold levels and increasing crop yield.

Aedes albopictus et Aedes aegypti sont deux espèces de moustiques invasives, vectrices de nombreux pathogènes et contre lesquelles les méthodes de lutte antivectorielle classiques sont peu efficaces. La Technique de l'Insecte Stérile en est une alternative durable et efficace reposant sur des lâchers répétés de grands nombres de moustiques mâles stérilisés par irradiation. Pour cela une méthode de séparation des sexes est nécessaire. Actuellement, les méthodes employées exploitent le dimorphisme de taille entre nymphes mâles et femelles, conduisant à un rendement faible, à un taux d'erreur élevé et à un gaspillage de ressources lié à l'élevage des larves femelles. Dans cette thèse, je me suis attachée à proposer une méthode de sexage résolvant ces problèmes. Pour ce faire, j'ai, dans un premier temps, inventorié les différentes méthodes de sexage développées au cours des 15 dernières années chez les Diptères. Parmi les approches prometteuses identifiées, j'ai retenu le développement de souches de sexage génétique basées sur l'intégration d'un transgène de fluorescence au sein des loci sexuels. Aussi, dans un deuxième temps, j'ai étudié chez Aedes albopictus le rôle et le fonctionnement de Nix, le gène de la masculinisation situé au coeur du locus M. Pour ce faire, j'ai construit des plasmides et généré des lignées de moustiques transgéniques exprimant les quatre isoformes principales de Nix, associées à des marqueurs fluorescents. J'ai ainsi pu démontrer que Nix était suffisant à conférer une masculinisation complète, produisant des pseudo-mâles fertiles, capables de voler et exprimant différentiellement les gènes myo-sex et myo-fem de façon similaire aux mâles naturels, malgré une certaine réduction de leur compétitivité. Par ailleurs, j'ai également observé une intégration préférentielle des constructions transgéniques à proximité du locus M par un phénomène de " transposon homing ". Ainsi, dans un troisième chapitre, je présente deux souches de sexage génétiques

Suppression or eradication of insect pest populations by the release of sterile insects is often dependent on supplementary methods of pest reduction to levels where the target pest population can be overflooded with sterile insects. Population suppression activities often take place in advance of, or coincide with, the production and release of sterile insects. Supplementary methods to remove breeding opportunities, or management methods that prevent access of pests or vectors to the hosts, may reduce the population or prevent damage or disease transmission. Insecticides have been used widely in direct applications or applied as baits, in traps, or on specific sites where the pest makes contact or reproduces, although they are increasingly being replaced by biopesticides. As sterile insect release does not kill the pest, adult biting pests or fertile mated females of the pests will continue to attack hosts after the release of sterile insects. Thus supplementary pest suppression programmes and quarantine measures are essential to prevent damage or the spread of disease. Eradication or effective pest management requires that the entire population of the pest be treated, or that the programme apply immigration barriers. It also requires taking into account interactions among control methods; they can be additive, synergistic or antagonistic. When supplementary pest control activities directly benefit the human population in areas being treated, such as in mosquito or screwworm control programmes, these area-wide suppression activities are usually acceptable to the public, but when the public receives no direct benefit from supplementary control activities such as in crop pest programmes, social resistance may develop unless public information is managed properly.

More than three thousand million people live with the risk of malaria. Due to the widespread resistance of mosquitoes to insecticides and of parasites to chemotherapies, previous gains made in disease reduction are being reversed. In addition to this perennial threat, there is now a rapid invasion of Aedes mosquitoes across the globe and the associated spread of the arboviruses (arthropod-borne viruses) they carry. One half of the world's population is now at risk of dengue, and chikungunya (having emerged from Africa) is an increasing public-health problem in Asia and the Americas. The economic and social costs of these diseases is so great that, in some areas, they have slowed the development of nations. Current vector-control methods are inadequate (especially against container-breeding species) because they are losing their effectiveness, the global burden of mosquito-borne diseases is increasing, and no specific drugs or effective global vaccines are available to treat or prevent the diseases. Therefore, there is a need for additional suppression methods to be applied as part of Integrated Vector Management (IVM). Since the early 2000s, there has been a renewed interest in applying the sterile insect technique (SIT) against mosquito vectors of disease. The explosive outbreaks of the Zika virus (and associated birth defects) across the tropics increased the urgency. The recent availability of technology to rear and release the sterilized males of many mosquito species on a large scale has increased the expectation that the SIT could help reduce the suffering caused by mosquitoborne diseases. Much progress has been made in developing the SIT technology for mosquitoes, based on historic SIT efforts and the experiences gained in the successful large-scale application of the technique against agricultural pest species. The SIT is a suitable technology for suppressing mosquitoes because: (1) they can be mass-reared in a laboratory, (2) natural sexual dimorphism in ma

Background: Crop pests are among the greatest threats to food security, generating broad economic, social, and environmental impacts. The impacts of crop pests can be reduced by identifying the conditions that generate them early. These pests interact with their hosts and the environment through complex pathways, and it is increasingly common to find professionals from different areas (farmers, technicians, plant pathologists, computer scientists, economists, sociologists, etc.) gathering into projects that attempt to deal with that complexity most often involving several crop pests. A pest development forecasting can be made using prediction models and it is required for three reasons: economic impact, safety, and justification of control methods. Given this situation, it is necessary to build interdisciplinary work guides that allow the construction of models for the comprehensive management of pest development capable of overcoming the challenges imposed by the presence or absence of data. Aims: Propose a conceptual model for the detection of favorable conditions for coffee pests in a smart farming environment, based on the use of data value and variety, and expert knowledge. Methods: Starting from theoretical references on the realization of mappings and systematic reviews of the literature, the approach proposes a series of steps that lead to a State of Science as a knowledge base for modeling tasks. The modeling tasks are framed in knowledge-based modeling methodologies, as well as data-based modeling. Results: A conceptual model that guides activities for modeling and forecasting the development of diseases and pests in crops, where implementation details are subject to existing methodologies and frameworks. Forecasting solutions can be approached through models based on knowledge and data, according to the requirements and available elements of the person or group of people who will carry out the modeling based on the proposed processes. Additionally, a phas

More than three thousand million people live with the risk of malaria. Due to the widespread resistance of mosquitoes to insecticides and of parasites to chemotherapies, previous gains made in disease reduction are being reversed. In addition to this perennial threat, there is now a rapid invasion of Aedes mosquitoes across the globe and the associated spread of the arboviruses (arthropod-borne viruses) they carry. One half of the world's population is now at risk of dengue, and chikungunya (having emerged from Africa) is an increasing public-health problem in Asia and the Americas. The economic and social costs of these diseases is so great that, in some areas, they have slowed the development of nations. Current vector-control methods are inadequate (especially against container-breeding species) because they are losing their effectiveness, the global burden of mosquito-borne diseases is increasing, and no specific drugs or effective global vaccines are available to treat or prevent the diseases. Therefore, there is a need for additional suppression methods to be applied as part of Integrated Vector Management (IVM). Since the early 2000s, there has been a renewed interest in applying the sterile insect technique (SIT) against mosquito vectors of disease. The explosive outbreaks of the Zika virus (and associated birth defects) across the tropics increased the urgency. The recent availability of technology to rear and release the sterilized males of many mosquito species on a large scale has increased the expectation that the SIT could help reduce the suffering caused by mosquitoborne diseases. Much progress has been made in developing the SIT technology for mosquitoes, based on historic SIT efforts and the experiences gained in the successful large-scale application of the technique against agricultural pest species. The SIT is a suitable technology for suppressing mosquitoes because: (1) they can be mass-reared in a laboratory, (2) natural sexual dimorphism in ma

Background: Crop pests are among the greatest threats to food security, generating broad economic, social, and environmental impacts. The impacts of crop pests can be reduced by identifying the conditions that generate them early. These pests interact with their hosts and the environment through complex pathways, and it is increasingly common to find professionals from different areas (farmers, technicians, plant pathologists, computer scientists, economists, sociologists, etc.) gathering into projects that attempt to deal with that complexity most often involving several crop pests. A pest development forecasting can be made using prediction models and it is required for three reasons: economic impact, safety, and justification of control methods. Given this situation, it is necessary to build interdisciplinary work guides that allow the construction of models for the comprehensive management of pest development capable of overcoming the challenges imposed by the presence or absence of data. Aims: Propose a conceptual model for the detection of favorable conditions for coffee pests in a smart farming environment, based on the use of data value and variety, and expert knowledge. Methods: Starting from theoretical references on the realization of mappings and systematic reviews of the literature, the approach proposes a series of steps that lead to a State of Science as a knowledge base for modeling tasks. The modeling tasks are framed in knowledge-based modeling methodologies, as well as data-based modeling. Results: A conceptual model that guides activities for modeling and forecasting the development of diseases and pests in crops, where implementation details are subject to existing methodologies and frameworks. Forecasting solutions can be approached through models based on knowledge and data, according to the requirements and available elements of the person or group of people who will carry out the modeling based on the proposed processes. Additionally, a phas

Suppression or eradication of insect pest populations by the release of sterile insects is often dependent on supplementary methods of pest reduction to levels where the target pest population can be overflooded with sterile insects. Population suppression activities often take place in advance of, or coincide with, the production and release of sterile insects. Supplementary methods to remove breeding opportunities, or management methods that prevent access of pests or vectors to the hosts, may reduce the population or prevent damage or disease transmission. Insecticides have been used widely in direct applications or applied as baits, in traps, or on specific sites where the pest makes contact or reproduces, although they are increasingly being replaced by biopesticides. As sterile insect release does not kill the pest, adult biting pests or fertile mated females of the pests will continue to attack hosts after the release of sterile insects. Thus supplementary pest suppression programmes and quarantine measures are essential to prevent damage or the spread of disease. Eradication or effective pest management requires that the entire population of the pest be treated, or that the programme apply immigration barriers. It also requires taking into account interactions among control methods; they can be additive, synergistic or antagonistic. When supplementary pest control activities directly benefit the human population in areas being treated, such as in mosquito or screwworm control programmes, these area-wide suppression activities are usually acceptable to the public, but when the public receives no direct benefit from supplementary control activities such as in crop pest programmes, social resistance may develop unless public information is managed properly.

Le moustique tigre, Aedes albopictus, représente une menace sanitaire par la transmission de maladies virales humaines. Malgré l'existence de moyens de lutte, le contrôle des populations d'Ae. albopictus reste un enjeu contraint par une connaissance fine de leur dynamique dans l'espace et le temps. Dans ce contexte, les modèles mathématiques sont des outils de choix pour tester et optimiser ces stratégies de contrôle. L'objectif de cette thèse était d'explorer les effets des méthodes de contrôle sur les populations d'Ae. albopictus en milieu tropical (La Réunion) et tempéré (Montpellier). L'étude s'est basée sur l'utilisation de modèle déterministe détaillant l'ensemble du cycle de vie du moustique, piloté par le climat et l'abondance de gîtes larvaires. Nous avons intégré au modèle les effets de différentes méthodes de lutte sur la dynamique des populations d'Ae. albopictus. Une attention particulière a été portée aux méthodes basées sur des lâchers de mâles stériles. L'analyse du modèle nous a permis de mieux comprendre et identifier les stratégies de lutte efficaces en terme de réduction et résilience des populations d'Ae. albopictus, afin de les optimiser en conséquence. Les stratégies de lutte intégrée ont pour objectif final de prévenir l'émergence d'épidémie. C'est pourquoi le modèle de dynamique des populations à La Réunion a été couplé avec un modèle épidémiologique. Des études supplémentaires devront être réalisées pour ajuster les prédictions du modèle avant de pouvoir étudier l'impact de stratégies de lutte intégrée sur la transmission de la dengue.

Tsetse eradication continues to be a top priority for African governments including that of Senegal, which embarked on a project to eliminate Glossina palpalis gambiensis from the Niayes area, following an area-wide integrated pest management approach with an SIT component. A successful SIT programme requires competitive sterile males of high biological quality. This may be hampered by handling processes including irradiation and the release mechanisms, necessitating continued improvement of these processes, to maintain the quality of flies. A new prototype of an automated chilled adult release system (Bruno Spreader Innovation, (BSI™)) for tsetse flies was tested for its accuracy (in counting) and release rate consistency. Also, its impact on the quality of the released sterile males was evaluated on performance indicators, including flight propensity, mating competitiveness, premating and mating duration, insemination rate of mated females and survival of male flies. The BSITM release system accurately counted and homogenously released flies at the lowest motor speed set (0.6 rpm), at a consistent rate of 60±9.58 males/min. Also, the release process, chilling (6 ± 1°C) and passing of flies through the machine) had no significant negative impact on the male flight propensity, mating competitiveness, premating and mating durations and the insemination rates. Only the survival of flies was negatively affected whether under feeding or starvation. The positive results of this study show that the BSI™ release system is promising for use in future tsetse SIT programmes. However, the negative impact of the release process on survival of flies needs to be addressed in future studies and results of this study confirmed under operational field conditions in West Africa.