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Resistance to insecticides in the mosquito Anopheles gambiae s.l can jeopardize malaria vector control strategies. Previous studies have shown that the agricultural chemicals, used particularly for cotton protection, selected the insecticide resistant malaria vectors. Our study aimed at assessing the impact of three cotton pest management strategies in different ecological settings (conventional, organic and transgenic cotton growing areas) on the i) susceptibility to insecticides belonging to pyrethroids, DDT, carbamate and organophosphate tested on the main malaria vectors and ii) frequencies of kdr L1014F, during rainy season of 2008, 2009, 2013 and 2014 in Burkina Faso. From 2008 to 2014, most of populations of An. gambiae s.l from the three cotton growing areas exhibited a reduction in susceptibility to almost all insecticide classes. The frequency of kdr L1014F mutations varied depending on both localities and species within the An. gambiae complex, but no relationship was found between the cotton pest control strategies and the frequency of kdr L1014F. These results confirm the worrying status of insecticide multi-resistance within the vector mosquito species from Burkina Faso. [ABSTRACT FROM AUTHOR]

In Burkina Faso, products and nests of insect are used for therapeutic purposes in traditional medicine. However, this use by local populations is marginal and empirical. The objective of this study was to evaluate the antimicrobial activity of extracts of bees’ products and termite nests. Thus, the collected termite nests were finely ground. Hydroethanolic extraction of bioactive molecules with potential antibacterial activity was performed according to standard methods. The agar diffusion method was used to test the antibacterial activity of hydroethanolic extracts of honey bee, bee wax, propolis, and termite nests against 22 pathogenic strains by inhibition diameter. Imipenem and nystatin were used as a positive control for bacterial and fungal strains respectively. The extraction yields varied from 7.33 to 35.39% depending on the content of soluble matter. All extracts of bees’ products and termite nests tested showed inhibitory activities. The inhibition diameters varied depending on the extract and strain tested. The largest diameter of inhibition (26 ± 0.0 mm) was obtained using the nest extract of Macrotermes bellicosus against Salmonella Typhimurium ATCC14028. The lowest diameter of inhibition was 7 ± 0.0 mm obtained with honey extract against Pseudomonas aeruginosa ATCC27853. Index multi-resistance of the extracts tested were between 0.2 and 0.6. Interestingly, the inhibition diameters and activity coefficient of certain products and nest extracts of insects were sometimes greater than those of imipenem/nystatin against the strains tested. This study revealed the antimicrobial potential of termite nest extracts and hive products against pathogens.Highlights: Highlighted of entomotherapeutic potential of bees’ products and termite nests. Importance of bees’ products and termite nests as alternative treatment for diseases. Bioactive compounds of bees’ products and termite nests involved in the treatment of disease by traditional medicine. [ABSTRACT FROM AUTHOR]

Anopheles gambiae and Anopheles coluzzii mosquitoes, two major malaria vectors in sub‐Saharan Africa, exhibit selectivity among plant species as potential food sources. However, it remains unclear if their preference aligns with optimal nutrient intake and survival. Following an extensive screening of the effects of 31 plant species on An. coluzzii in Burkina Faso, we selected three species for their contrasting effects on mosquito survival, namely Ixora coccinea, Caesalpinia pulcherrima, and Combretum indicum. We assessed the sugar content of these plants and their impact on mosquito fructose positivity, survival, and insemination rate, using Anopheles coluzzii and Anopheles gambiae, with glucose 5% and water as controls. Plants displayed varying sugar content and differentially affected the survival, sugar intake, and insemination rate of mosquitoes. All three plants were more attractive to mosquitoes than controls, with An. gambiae being more responsive than An. coluzzii. Notably, C. indicum was the most attractive but had the lowest sugar content and offered the lowest survival, insemination rate, and fructose positivity. Our findings unveil a performance–preference mismatch in An. coluzzii and An. gambiae regarding plant food sources. Several possible reasons for this negative correlation between performance and preference are discussed. [ABSTRACT FROM AUTHOR]

Insects are known for their harmful effects. However, they also benefit humans, animals, plants, and ecosystems. Its beneficial uses include entomophagy and entomotherapy. This study aimed to evaluate the antibacterial activity of insect extracts against Gram-negative bacteria. Antibacterial activities of thirteen crude extracts of medicinal insects were tested against twelve Gram-negative bacteria by diffusion on agar. Imipenem was used as an antibiotic for positive control. The thirteen extracts acted differently against certain Gram-negative bacteria. The largest inhibition diameter was for extracts of Cirina butyrospermi and Mylabris variabilis against Pseudomonas aeruginosa ATCC27853 and Salmonella enteritidis ATCC13076, respectively. The diameters of inhibition obtained using imipenem against these same bacterial strains were 13.0 ± 0.0 mm and 22 ± 1.0 mm, respectively. The lowest inhibition diameter (7.5 ± 0.0 mm) was obtained using Anopheles gambiae extract against Salmonella Typhimurium ATCC14028. Imipenem was active on all strains tested. The highest values of the index multi-resistance to insect's extracts were reported for Pseudomonas aeruginosa ATCC9027 and Serratia odorifera 652411. Overall, the results of this study confirmed the antibacterial activities of insects used by traditional health practitioners to treat different pathologies. Entomotherapy could be an alternative treatment for certain infectious pathologies caused by gram-negative bacteria. [ABSTRACT FROM AUTHOR]

The pollination syndrome of the African custard apple (Annona senegalensis Pers.; Annonaceae) was investigated to gain insights into the reproductive strategy of this multipurpose wild shrub. Flower visitors were collected and frequently surveyed in the morning on 30 flowers of 30 plants per site, at four sites across the Sudanian and Sudano-Sahelian climatic zones of Burkina Faso during the flowering season, from May to June. A total of nine species of insects including Coleoptera (Curculionidae, Scarabeidae), Hymenoptera (Formicidae) and Diptera (Tephritidae) were observed visiting flowers. Among the recorded insects, two sympatric species of weevil (Curculioninae, Ochyromerini, Endaeus castus Schoenherr and Endaeusfloralis Marshall) were by far the most abundant (97% of specimens) and were observed on all the 120 flowers sampled. Both species were observed on the fleshy petals of the cantharophilous flowers of Annona senegalensis that they use as substrate for the development of larval stages. These observations echo with the ever-growing number of researches highlighting the major role of weevils in the pollination of the pantropical Annonaceae. Our study provides first evidence of brood-site mutualism between an Annonaceae species and its specialized weevils pollinators. [ABSTRACT FROM AUTHOR]

Success in reducing malaria transmission through vector control is threatened by insecticide resistance in mosquitoes. Although the proximal molecular mechanisms and genetic determinants involved are well documented, little is known about the influence of the environment on mosquito resistance to insecticides. The aim of this study was to assess the effect of plant sugar feeding on the response of Anopheles gambiae sensu lato to insecticides. Adults were fed with one of four treatments, namely a 5% glucose control solution, nectariferous flowers of Barleria lupulina, of Cascabela thevetia and a combination of both B. lupulina + C. thevetia. WHO tube tests were performed with 0.05% and 0.5% deltamethrin, and knockdown rate (KD) and the 24 h mosquito mortality were measured. Plant diet significantly influenced mosquito KD rate at both concentrations of deltamethrin. Following exposure to 0.05% deltamethrin, the B. lupulina diet induced a 2.5 fold-increase in mosquito mortality compared to 5% glucose. Species molecular identification confirmed the predominance of An. gambiae (60% of the samples) over An. coluzzii and An. arabiensis in our study area. The kdr mutation L1014F displayed an allelic frequency of 0.75 and was positively associated with increased phenotypic resistance to deltamethrin. Plant diet, particularly B. lupulina, increased the susceptibility of mosquitoes to insecticides. The finding that B. lupulina-fed control individuals (i.e. not exposed to deltamethrin) also displayed increased 24 h mortality suggests that plant-mediated effects may be driven by a direct effect of plant diet on mosquito survival rather than indirect effects through interference with insecticide-resistance mechanisms. Thus, some plant species may weaken mosquitoes, making them less vigorous and more vulnerable to the insecticide. There is a need for further investigation, using a wider range of plant species and insecticides, in combination with other relevant environmental factors, to better understand the expression and evolution of insecticide resistance. [ABSTRACT FROM AUTHOR]

Although the defatted flour and the protein concentrates of I Macrotermes subhyalinus i had high protein contents compared to those of I Brachytrupes membranaceus i , these proteins were not endowed with functional properties. Although the protein isolate of I Brachytrupes membranaceus i had the highest fat absorption capacity, it had a low hydrophobic amino acid content (33.59 mg/100 g protein) compared to that of the concentrates of I Brachytrupes membranaceus i (40.34 mg/100 g protein). The low-fat absorption capacity of the isolate of I Macrotermes subhyalinus i could be due to its low hydrophobic amino acid content (25.77 mg/100 g protein) compared to the protein isolate of I Brachytrupes membranaceus, i which had a high hydrophobic amino acid content (33.59 mg/100 g protein). Proteins Contents of Protein Concentrates and Isolates Protein contents of the protein isolate ranged from 88.68 to 89.32%, while the protein concentrates varied from 50.96 to 63.82% (Table 4). [Extracted from the article]

Background: Some insects are harmful to humans, plants and animals, but some of them can also be a source of proteins, fats, vitamins and minerals and be of therapeutic value. The therapeutic potential requires that medicinal insects and their derived products need to be scrutinized. This study highlights the indigenous knowledge related to their use of medicinal insects in peri-urban and urban areas of Burkina Faso. Methods: The survey was carried out among 60 traditional healers spread across two phytogeographical zones of Burkina Faso. The questionnaire focused on medicinal insects used by experienced traditional healers. Chi-square tests and principal component analysis were performed to test for significant differences regarding knowledge of how insects in phytogeographically different areas were used therapeutically in connection with different disease categories. Results: A total of 19 species of medicinal insects belonging to 6 orders were cited in connection with treatments of at least 78 pathologies and symptoms. Most frequently mentioned was gastroenteritis. Our study showed that 48.78% of the insects and their products were associated with 46 plant species for the treatment of pathologies. In addition, honey, beeswax and nests were the most widely insect products used. Conclusion: The current study allows us to identify medicinal insects as well as their products used in the treatment of pathologies and symptoms, suggesting the presence of a considerable diversity of therapeutically important insect species. These insects are used alone and/or with their products but often in association with medicinal plants. The results constitute a useful database for future studies of medicinal insects in central and western parts of Burkina Faso. [ABSTRACT FROM AUTHOR]

Background: Escherichia coli (E. coli) is the most common bacterial species implicated in various types of infections including septicemia, gastroenteritis, urinary tract infections, meningitis and others pathologies. These involve several bacterial clones with multidrug resistance making them difficult to treat. The aims of this study was to perform molecular typing of E. coli strains using universal primer (GTG)5. In this study, 53 E. coli strains were collected from inpatients and outpatients. The test of antimicrobial sensibility was realized using CA-SFM /EUCAST method and strains were identified by conventional microbiological tests. The carbapenemase-producing strains were demonstrated by phenotypic method. Bacterial DNA was extracted by boiling method. (GTG)5-PCR was used for strain subtyping. The DendroUPGMA software was used for grouping of strains from the genetic fingerprints obtained by (GTG)5-PCR. Results: Antibiotic susceptibility test revealed that all strains were multi-drug resistant (MDR). Its strains showed resistance to at least three different families of antibiotics. Of this MDR strains, only one was a metallo-β-lactamase producer. The dendrogram obtained using genetic fingerprinting allowed the E. coli strains to be grouped into 22 clusters (G1 to G22). Conclusion: The (GTG) 5-PCR assay enabled rapid molecular typing of E. coli strains. The strains of E. coli typed in this study would belong to different clones. [ABSTRACT FROM AUTHOR]

Callosobruchus maculatus is the main pest of stored cowpeas in West Africa. To control this pest, chemicals are frequently used during post-harvest storage. In this study we assessed insecticide resistance in C. maculatus populations collected from Burkina Faso, Senegal and Niger. Enzyme analysis was also performed to detect the basic mechanisms underlying insecticide resistance. Burkina Faso western strains proved to be more resistant to cypermethrin (RR50 = 25–26.6) and to have moderate resistance to permethrin (RR50 = 10.5-13) and Pirimiphos-methyl (RR50 = 8–11). The enzymatic activities confirmed insecticide resistance in these strains (NA esterase: 0.2- 0.12 µM/mg/min; PNPA esterase: 1.15–1.96 µM/mg/min; GST: 1.01–1.32 µM/mg/min; oxidase: 0.11–0.12 µM/mg/min). Dakar and Niamey strains were less resistant to cypermethrin, permethrin, Chlorpyrifos-methyl and Pirimiphos-methyl. Resistance to OP and Py is likely due to the selection pressure imposed by their systematic use in fields and storage systems. Alternative pest control methods should be considered for resistance management or for delaying it as much as possible taking into account insect origin and behavior. [ABSTRACT FROM AUTHOR]

Background: Besides feeding on blood, females of the malaria vector Anopheles gambiae sensu lato readily feed on natural sources of plant sugars. The impact of toxic secondary phytochemicals contained in plant-derived sugars on mosquito physiology and the development of Plasmodium parasites remains elusive. The focus of this study was to explore the influence of the alkaloid ricinine, found in the nectar of the castor bean Ricinus communis, on the ability of mosquitoes to transmit Plasmodium falciparum. Methods: Females of Anopheles gambiae and its sibling species Anopheles coluzzii were exposed to ricinine through sugar feeding assays to assess the effect of this phytochemical on mosquito survival, level of P. falciparum infection and growth rate of the parasite. Results: Ricinine induced a significant reduction in the longevity of both Anopheles species. Ricinine caused acceleration in the parasite growth rate with an earlier invasion of the salivary glands in both species. At a concentration of 0.04 g l−1 in An. coluzzii, ricinine had no effect on mosquito infection, while 0.08 g l−1 ricinine-5% glucose solution induced a 14% increase in An. gambiae infection rate. Conclusions: Overall, our findings reveal that consumption of certain nectar phytochemicals can have unexpected and contrasting effects on key phenotypic traits that govern the intensity of malaria transmission. Further studies will be required before concluding on the putative role of ricinine as a novel control agent, including the development of ricinine-based toxic and transmission-blocking sugar baits. Testing other secondary phytochemicals in plant nectar will provide a broader understanding of the impact which plants can have on the transmission of vector-borne diseases. [ABSTRACT FROM AUTHOR]

Edible insects constitute a potential source of alternative proteins as a food supplement. The present study aimed to investigate the chemical composition, energy and nutritional values, the digestibility and functional properties of Carbula marginella (Thunberg) and Cirina butyrospermi (Vuillet) defatted flour, protein concentrates, and isolates. Carbula marginella has shown the highest content of protein (41.44%), lipid (51.92%), calcium (33.92 mg/100 g) and sodium (185.84 mg/100 g) while the highest contents of carbohydrate (34.54%), ash (4.77%), iron (31.27 mg/100 g), magnesium (150.09 mg/100 g), and potassium (1277 mg/100 g) have been observed for C. butyrospermi. Linoleic (30.23%), palmitic (27.54%), oleic (26.41%) and stearic (8.90%) acids were the most dominant fatty acids found in C. marginella. Cirina butyrospermi was characterized by high levels of oleic (27.01%), stearic (21.02%), linolenic (20.42%), palmitic (13.06%), and linoleic (8.01%) acids. Protein and essential amino acid contents of the protein isolates in both insect species were 1.7–2 times higher than that of their defatted flours. The protein isolate of C. marginella exhibited the highest protein digestibility (87.63%), while the highest fat absorption capacity (8.84 g/g) and foaming capacity (48.40%) have been obtained from the protein isolate of C. butyrospermi. These findings indicate that the protein concentrates and isolates of C. marginella and C. butyrospermi have great potential for industrial applications. [ABSTRACT FROM AUTHOR]

Background: Mating swarm segregation in closely related insect species may contribute to reproductive isolation. Visual markers are used for swarm formation; however, it is unknown whether they play a key role in swarm location, species segregation and sex aggregation. Methods: Using two sympatric closely related species of the Anopheles gambiae complex, An. coluzzii and An. gambiae (s.s.), we investigated in both laboratory and semi-field conditions (i) whether males of the two species use visual markers (black cloths) to locate their swarm; and (ii) whether the presence/absence and size of the marker may differentially affect swarm characteristics. We also investigated whether conspecific virgin females use these markers to join male swarm sites. Results: We showed that males of the two species used visual markers but in different ways: An. coluzzii swarm right above the marker whereas An. gambiae (s.s.) locate their swarm at a constant distance of 76.4 ± 0.6 cm from a 20 × 20 cm marker in the laboratory setup and at 206 ± 6 cm from a 60 × 60 cm marker in the semi-field setup. Although increased marker size recruited more mosquitoes and consequently increased the swarm size in the two species, An. coluzzii swarms flew higher and were stretched both vertically and horizontally, while An. gambiae (s.s.) swarms were only stretched horizontally. Virgin females displayed a swarm-like behavior with similar characteristics to their conspecific males. Conclusions: Our results provided experimental evidence that both An. coluzzii and An. gambiae (s.s.) males use ground visual markers to form and locate their swarm at species-specific locations. Moreover, the marker size differentially affected swarm characteristics in the two species. Our results also showed that virgin females displayed a swarm-like behavior. However, these "swarms" could be due to the absence of males in our experimental conditions. Nevertheless, the fact that females displayed these "swarms" with the same characteristics as their respective males provided evidence that visual markers are used by the two sexes to join mating spots. Altogether, this suggests that visual markers and the way species and sexes use them could be key cues in species segregation, swarm location and recognition. [ABSTRACT FROM AUTHOR]

Swarming is a key part of the natural system of reproduction of anopheline mosquito populations, and a better understanding of swarming and mating systems in a targeted species in its natural habitat would contribute to better design control strategies with a greater chance of success. Our study investigated the monthly occurrence of swarming and the mating frequency (within swarms) of Anopheles arabiensis in Dioulassoba, Burkina Faso and their relationship with local environmental factors. Mosquitoes collected from swarms were described in terms of body size, recent sugar meal intake, and female repletion, insemination, and Plasmodium falciparum infection status. Swarms of An. arabiensis were found in each month of the year. Both start and end times of swarming varied significantly between months, correlating with the time of sunset. Swarming mostly started after or coincided with sunset from late July to early October but occurred before sunset from late October to early July. Swarming duration, the number of mosquitoes and mating pairs per swarm, and time to first mating were significantly different between months in an inverse relationship with the monthly rainfall. The number of mating pairs was strongly and positively correlated with swarm size. Almost all the females caught in copula were inseminated but a very few were blood fed; no P. falciparum infection was observed. Males caught in copula and in solo were similar in body size and in the proportion which had taken a recent sugar meal. Our investigations showed that An. arabiensis reproductive activities are most frequent during the dry season, suggesting either the species’ preference for dry climatic conditions or a lack of available breeding sites during the rainy season due to the seasonal flooding in this area. Targeting interventions to kill mosquitoes in swarms or to achieve an over-flooding ratio of sterile males during the rainy season would increase their efficiency in reducing the population density of this vector. [ABSTRACT FROM AUTHOR]

Background: A novel strategy applying an organophosphate-based insecticide paint on doors and windows in combination with long-lasting insecticide-treated nets (LLINs) was tested for the control of pyrethroid-resistant malaria vectors in a village setting in Vallée du Kou, a rice-growing area west of Burkina Faso. Methods: Insecticide Paint Inesfly 5A IGR™, comprised of two organophosphates and an insect growth regulator, was applied to doors and windows and tested in combination with pyrethroid-treated LLINs. The killing effect was monitored for 5 months by early morning collections of anophelines and other culicids. The residual efficacy was evaluated monthly by WHO bioassays using Anopheles gambiae ‘Kisumu’ and local populations of Anopheles coluzzii resistant to pyrethroids. The spatial mortality efficacy (SME) at distances of 1 m was also assessed against pyrethroidsusceptible and -resistant malaria vectors. The frequency of L1014F kdr and Ace-1R G119S mutations was, respectively, reported throughout the study. The Insecticide Paint Inesfly 5A IGR had been tested in past studies yielding a long-term mortality rate of 80% over 12 months against An. coluzzii, the local pyrethroid-resistant malaria vector. The purpose of the present study is to test if treating smaller, targeted surfaces (e.g. doors and windows) was also efficient in killing malaria vectors. Results: Treating windows and doors alone yielded a killing efficacy of 100% for 1 month against An. coluzzii resistant to pyrethroids, but efficacy reduced quickly afterwards. Likewise, WHO cone bioassays yielded mortalities of 80–100% for 2 months but declined to 90 and 40% 2 and 3 months after treatment, respectively. Mosquitoes exposed to insecticide paint-treated surfaces at distances of 1 m, yielded mortality rates of about 90–80% against local pyrethroidsresistant An. coluzzii during the first 2 months, but decreased to 30% afterwards. Anopheles coluzzii was reported to be exclusively the local malaria vector and resistant to pyrethroids with high L1014 kdr frequency. Conclusion: The combination of insecticide paint on doors and windows with LLINs yielded high mortality rates in the short term against wild pyrethroid-resistant malaria vector populations. A high SME was observed against laboratory strains of pyrethroid-resistant malaria vectors placed for 30 min at 1 m from the treated/control walls. The application of the insecticide paint on doors and windows led to high but short-lasting mortality rates. The strategy may be an option in a context where low cost, rapid responses need to be implemented in areas where malaria vectors are resistant to pyrethroids. [ABSTRACT FROM AUTHOR]

Background: Larval nutrition, particularly diet quality, is a key driver in providing sufficient numbers of high quality mosquitoes for biological control strategies such as the sterile insect technique. The diet currently available to mass rear Anopheles arabiensis, referred here to as the "IAEA diet", is facing high costs and difficulties concerning the availability of the bovine liver powder component. To promote more affordable and sustainable mosquito production, the present study aimed to find alternative diet mixtures. Eight cheaper diet mixtures comprised of varying proportions of tuna meal (TM), bovine liver powder (BLP), brewer's yeast (BY), and chickpea (CP) were developed and evaluated through a step by step assessment on An. arabiensis larvae and adult life history traits, in comparison to the IAEA diet which served as a basis and standard. Results: Four mixtures were found to be effective regarding larval survival to pupation and to emergence, egg productivity, adult body size and longevity. These results suggest that these different diet mixtures have a similar nutritional value that support the optimal development of An. arabiensis larvae and enhance adult biological quality and production efficiency, and thus could be used for mass rearing. Conclusions: Our study demonstrated that four different diet mixtures, 40 to 92% cheaper than the IAEA diet, can result in a positive assessment of the mosquitoes' life history traits, indicating that this mosquito species can be effectively mass reared with a significant reduction in costs. The mixture comprised of TM + BY + CP is the preferred choice as it does not include BLP and thus reduces the cost by 92% compared to the IAEA diet. [ABSTRACT FROM AUTHOR]

Widespread resistance of Anopheles sp. populations to pyrethroid insecticides has led to the search for sustainable alternatives in the plant kingdom. Among many botanicals, there is great interest in essential oils and their constituents. Many researchers have explored essential oils (EOs) to determine their toxicity and identify repellent molecules that are effective against Anopheles populations. Essential oils are volatile and fragrant substances with an oily consistency typically produced by plants. They contain a variety of volatile molecules such as terpenes and terpenoids, phenol-derived aromatic components and aliphatic components at quite different concentrations with a significant insecticide potential, essentially as ovicidal, larvicidal, adulticidal, repellency, antifeedant, growth and reproduction inhibitors. The current review provides a summary of chemical composition of EOs, their toxicity at different developmental stages (eggs, larvae and adults), their repellent effects against Anopheles populations, for which there is little information available until now. An overview of antagonist and synergistic phenomena between secondary metabolites, the mode of action as well as microencapsulation technologies are also given in this review. Finally, the potential use of EOs as an alternative to current insecticides has been discussed. [ABSTRACT FROM AUTHOR]

Many studies have shown the role of agriculture in the selection and spread of resistance of Anopheles gambiae s.l. to insecticides. However, no study has directly demonstrated the presence of insecticides in breeding sources as a source of selection for this resistance. It is in this context that we investigated the presence of pesticide residues in breeding habitats and their formal involvement in vector resistance to insecticides in areas of West Africa with intensive farming. This study was carried out from June to November 2013 in Dano, southwest Burkina Faso in areas of conventional (CC) and biological cotton (BC) growing. Water and sediment samples collected from breeding sites located near BC and CC fields were submitted for chromatographic analysis to research and titrate the residual insecticide content found there. Larvae were also collected in these breeding sites and used in toxicity tests to compare their mortality to those of the susceptible strain, Anopheles gambiae Kisumu. All tested mosquitoes (living and dead) were analyzed by PCR for species identification and characterization of resistance genes. The toxicity analysis of water from breeding sites showed significantly lower mortality rates in breeding site water from biological cotton (WBC) growing sites compared to that from conventional cotton (WCC) sites respective to both An. gambiae Kisumu (WBC: 80.75% vs WCC: 92.75%) and a wild-type strain (49.75% vs 66.5%). The allele frequencies L1014F, L1014S kdr, and G116S ace -1R mutations conferring resistance, respectively, to pyrethroids and carbamates / organophosphates were 0.95, 0.4 and 0.12. Deltamethrin and lambda-cyhalothrin were identified in the water samples taken in October/November from mosquitoes breeding in the CC growing area. The concentrations obtained were respectively 0.0147ug/L and 1.49 ug/L to deltamethrin and lambdacyhalothrin. Our results provided evidence by direct analysis (biological and chromatographic tests) of the role of agriculture as a source of selection pressure on vectors to insecticides used in growing areas. [ABSTRACT FROM AUTHOR]

BACKGROUND The taxonomy of the species complex Bemisia tabaci, a serious agricultural pest worldwide, is not well resolved yet, even though species delimitation is critical for designing effective control strategies. Based on a threshold of 3.5% mitochondrial ( mtCOI) sequence divergence, recent studies have identified 28 putative species. Among them, mitochondrial variability associated with particular symbiotic compositions (=cytotypes) can be observed, as in MED, which raises the question of whether it is a single or a complex of biological species. RESULTS Using microsatellites, an investigation was made of the genetic relatedness of Q1 and ASL cytotypes that belong to MED. Samples of the two cytotypes were collected in West Africa where they live in sympatry on the same hosts. Genotyping revealed a high level of differentiation, without evidence of gene flow. Moreover, they differed highly in frequencies of resistance alleles to insecticides, which were much higher in Q1 than in ASL. CONCLUSION Q1 and ASL are sufficiently reproductively isolated for the introgression of neutral alleles to be prevented, suggesting that they are actually different species. This indicates that nuclear genetic differentiation must be investigated within groups with less than 3.5% mtCOI divergence in order to elucidate the taxonomy of B. tabaci at a finer level. Overall, these data provide important information for pest management. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Bemisia tabaciGennadius is a major plant pest in many agricultural systems worldwide. It is a complex of cryptic species that differ in many ecological respects, including damage-causing potential. Monitoring the genetic composition ofB. tabacipopulations in the field is, therefore, essential for achieving effective control. Sequencing is costly and time consuming; thus, efficient diagnostic tools must be developed to perform epidemiological studies involving hundreds of individuals. Here, we describe a polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) method for identifying all the putative species comprising the Africa/Middle East/Asia Minor group, including those that are the most devastating crop pests. Moreover, intra-specific diversity associated with specific symbiotic bacteria known to manipulate insect host phenotypes can also be detected. In addition, this method discriminates between the Africa/Middle East/Asia Minor and the Sub-Saharan African groups, which are sympatric in some areas. This simple, reliable and cost-effective diagnostic tool is ideal for the rapid analysis of a high number of individuals and, thus, has potential applications in field contexts, where it could provide valuable baseline information for pest management programs. [ABSTRACT FROM PUBLISHER]

. 1. The whitefly Bemisia tabaci is a pest of many agricultural and ornamental crops worldwide and particularly in Africa. B. tabaci is a complex of more than 20 biotypes. Effective control of B. tabaci calls for a greater knowledge of the local biological diversity in terms of biotypes or putative species. Information is available about biotype distribution in Northern, Eastern, and Southern Africa, but data for Western Africa remain very scarce. At the time of this study, data were available for only three sampling sites in Burkina Faso, where three biotypes have been detected, the native Sub-Saharan Africa non-Silver Leafing (AnSL), the Sub-Saharan Africa Silverleafing (ASL), and the Mediterranean Q biotypes, but no information is available about their respective distributions on host plant species (Gueguen et al., 2010). 2. Our study describes the biotypes and symbiotic bacterial communities of B. tabaci sampled in three West African countries, Burkina Faso, Benin, and Togo. A total of 527 individuals were collected from seven cultivated host plants. 3. In the 20 localities studied, we found the same three biotypes AnSL, ASL, and Q previously detected in Burkina Faso. These biotypes display a specific pattern of geographical distribution influenced by the host plant species. In Benin and Togo, the ASL and AnSL biotypes were predominant, while in Burkina Faso, the Q biotype was dominant, with two sub-groups, Q1 and Q3 (recorded to date only in this country), and ASL individuals found in sympatry with Q1 individuals in some localities. As previously reported, each biotype and each genetic group harbours a specific community of symbiotic bacteria. [ABSTRACT FROM AUTHOR]

Bemisia tabaciGennadius is a one of the major pests of cotton crops worldwide. In Burkina Faso, data on resistance to neonicotinoids and carbamate insecticides related to species/biotypes remain very scarce. To evaluate the resistance status ofB. tabaciin Burkina Faso, four insecticides were tested using the leaf dip method on 10 field populations collected from cotton. The status of biotypes was also determined. Two biotypes, Q and ASL, were recorded. Only Q1 group was detected in Q biotype. A significant resistance to neonicotinoids and carbosulfan was shown in most of the populations tested. The highest resistance ratios (RRs) were recorded in populations from locations exhibiting only the Q1. However, the populations comprising a mix of Q1 and ASL appeared to be more susceptible to insecticides. Resistance to neonicotinoids may be related not only to the biotype status but also to the environmental factors and agricultural practices. The exclusive use of neonicotinoids against whiteflies on cotton in Burkina Faso is expected to continue to select for the resistant Q biotype and might threaten the short-term control of whitefly populations, thereby increasing the risk of outbreaks in different host plants and begomovirus transmission. [ABSTRACT FROM AUTHOR]

Background: The recent resurgence of interest in sterile insect techniques to control vector mosquitoes has renewed interest in novel methods for observing mating behavior. Malarial vectors of the Anopheles gambiae complex are known to mate in swarms at specific locations at dawn and dusk. Most knowledge of mosquito swarming behavior is derived from field observations and a few experimental studies designed to assess critical parameters that affect mosquito swarming. However, such studies are difficult to implement in the field because of uncontrollable environmental factors and mosquito conditions. Here, we present two experimental setups specifically designed to analyze mosquito swarming behavior and provide evidence that swarming behavior of mosquitoes can be generated and accurately assessed under both semi-field and laboratory conditions. Methods: The Mosquito Ecology Research Facility setup is a semi-field enclosure made of 12 compartments (10.0 × 6.0 × 4.5 m L × W × H each) exposed to ambient meteorological and lighting conditions. The laboratory setup consists of a windowless room (5.1 × 4.7 × 3.0 m) in which both environmental and mosquito conditions can be controlled. In the two setups, 300 3–6-days-old An. coluzzii virgin males were released and some swarm characteristics were recorded such as the time at which the swarm started, the number of mosquitoes in the swarm and the height. Climatic conditions in the semi-field setup were also recorded. Results: In both setups, An. coluzzii males displayed stereotyped and consistent swarming behavior day after day; males gradually gather into a swarm over a ground marker at sunset, flying in loops in relation to specific visual features on the ground. Although semi-field climatic conditions were slightly different from outdoors conditions, they did not impede swarming behavior and swarm characteristics were similar to those observed in the field. Conclusions: Swarm characteristics and their consistency across days provide evidences that these facilities can be used confidently to study swarming behavior. These facilities come to complement existing semi-field setups and pave the way for new experimental studies which will enhance our understanding of mating behavior but also mosquito ecology and evolution, a prerequisite for application of genetic approaches to malaria control. [ABSTRACT FROM AUTHOR]

The black soldier fly, yellow mealworm and house fly are known for their wide distribution, ease of breeding, and environmental and nutritional attributes. Diets based on these fly proteins for the rearing of mosquito larvae are more accessible and affordable when compared to the reference IAEA diet which consists largely of costly livestock products such as bovine liver powder. Following a step-by-step assessment, we developed diet mixtures based on insect meal for the optimal mass production of Aedes albopictus and Ae. aegypti. Based on the assessed parameters including mosquito egg hatch, body size, flight ability, longevity and diet cost reduction, two mixtures are recommended: 1/2 tuna meal (TM) + 7/20 black soldier fly (BSF) + 3/20 brewer's yeast and 1/2 TM + 1/2 BSF. These findings, which could be adapted to other mosquito species, provide alternative protein sources for mass rearing insects for genetic control strategies. [ABSTRACT FROM AUTHOR]

Background: Insects play an important role as a diet supplement in Burkina Faso, but the preferred insect species vary according to the phytogeographical zone, ethnic groups, and gender. The present study aims at documenting indigenous knowledge on edible insects in Burkina Faso. Methods: A structured ethno-sociological survey was conducted with 360 informants in nine villages located in two phytogeographical zones of Burkina Faso. Identification of the insects was done according to the classification of Scholtz. Chi-square tests and principal component analysis were performed to test for significant differences in edible insect species preferences among phytogeographical zones, villages, ethnic groups, and gender. Results: Edible insects were available at different times of the year. They were collected by hand picking, digging in the soil, and luring them into water traps. The edible insects collected were consumed fried, roasted, or grilled. All species were indifferently consumed by children, women, and men without regard to their ages. A total of seven edible insect species belonging to five orders were cited in the Sudanian zone of Burkina Faso. Macrotermes subhyalinus (Rambur), Cirina butyrospermi (Vuillet, 1911), Kraussaria angulifera (Krauss, 1877), Gryllus campestris (Linnaeus, 1758), and Carbula marginella (Thunberg) (35.66–8.47% of the citations) were most cited whereas Rhynchophorus phoenicis (Fabricius, 1801) and Oryctes sp. (3.41–0.27%) were least cited. Cirina butyrospermi was most cited in the South Sudanian zone, whereas Macrotermes subhyalinus and Kraussaria angulifera were most cited in the North Sudanian zone but were cited in all nine villages. Cirina butyrospermi was preferred by Bobo, Guin, Sambla, Senoufo, and Turka ethnic groups whereas Macrotermes subhyalinus was preferred by Fulani, Mossi, and Toussian ethnic groups. Oryctes sp. was cited only by the Toussian. Conclusion: A diversity of edible insects was consumed in both the South and North Sudanian zone of Burkina Faso with significant differences in species preferences according to phytogeographical zones, villages, ethnic groups, and gender. [ABSTRACT FROM AUTHOR]