160 research outputs found

    Macroinvertebrate Communities Associated with Hydrilla verticillata (Royle, 1839) and Relationship with Environmental Factors in Ono Lagoon, Southeast of Côte d’Ivoire

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    The macroinvertebrates associated with Hydrilla verticillata was studied in Ono lagoon, South-eastern of Côte d'Ivoire. Monthly samples of macrophytes with their associated macroinvertebrates were collected in upstream, centre and downstreamusing a Van veen grab of 0.314 m2 internal area. The environmental variables (temperature, transparency, depth, conductivity, TDS, pH, dissolved oxygen, , , and ) were also recorded. A total of 71 taxa belonging to 28 families, 11 orders, 05 classes and 03 phyla of which 40 taxa were recorded in upstream, 45 taxa in centre and 44 taxa in downstream. Insects numerically dominated the capture, comprising 91.55% of the collectedtaxa with Odonata and Coleoptera being the most diverse and abundant groups. The density was higher in upstream (1407ind. per 100 g d.w.) and lower in downstream (1062 ind. per 100 g d.w.), whist theLibellulidae and Corduliidae exhibited the highest density communities. The rarefied richness did not show spatial variation but vary significantly between seasons. The Evenness did not show spatial and seasonal variations. However, Shannon diversity index varied significantly between sites and seasons. From the results of RDA analysis, conductivity and pH showed a strong environmental gradient and had a structuring effect on macroinvertebrate communities

    Piégeage des Mouches des Fruits (Diptera : Tephritidae) À Base D’extraits de Ocimum Basilicum L. (Lamiaceae) : Cas de Bactrocera Dorsalis, Principal Ravageur de Mangues en Côte d’Ivoire

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    Les cultures fruitières, en particulier la mangue en Côte d’Ivoire, sont sous la menace des mouches des fruits. Les dégâts se sont accrus avec l’invasion de Bactrocera dorsalis. En outre, la baisse des pertes en vergers de manguiers exige l’utilisation du méthyl eugénol pour sa détection et le suivi du monitoring de sa population. Malheureusement, les attractifs sexuels spécifiques de mouchessont inaccessibles aux producteurs de la Côte d’Ivoire. L’objectif de cette étude est d’évaluer l’efficacité de Ocimum basilicum dans de la capture de B. dorsalis. Ces trois formulations du basilic (feuilles fraîches malaxées, poudre de basilic et macérât du basilic) et le méthyl eugénol sont utilisées en piégeage dans les vergers de manguiers à Korhogo. Les pièges ont été relevés chaque semaine et chaque jour respectivement pour le Méthyl eugénol et les formulations du basilic. Les formulations ont permis de capturer une importante population de B. dorsalis (99,41 %) avec une prévalence (FTD) moyenne journalière de 10,141 individus/jour/piège et d’autres espèces de mouches de fruits. La poudre de basilic montre une rémanence plus longue (28,67 ± 18,17 jours) tandis que le macérât de basilic montre une capture hebdomadaire plus élevée (513,4 ± 72,34 individus). Les captures moyennes les plus élevées ont été observées avec le Macérât de basilic (4419 ± 1090 individus) et le Méthyl eugénol (4899,67 ± 1511,74 individus). Le macérât de feuilles fraîches de basilic et la poudre de feuilles sèches de basilic peuvent être recommandées auprès des producteurs de mangues dans la lutte contre B. dorsalis. Fruit crops, especially mangoes in Côte d'Ivoire are threatened by the fruit flies. The damage has increased with the invasion of Bactrocera dorsalis. In addition, the decline in mango orchard losses requires the use of methyl eugenol for the detection and monitoring of Bactrocera population. Unfortunately, the sex-specific attractants of flies are inaccessible to producers in Côte d'Ivoire. The aims of this study is to evaluate the efficacy of Ocimum basilicum in the capture of B. dorsalis. Three basil formulations (fresh mixed leaves, basil powder and basil macerate) and methyl eugenol are used for trapping in mango orchards in Korhogo. The captured insects were collected weekly and daily for methyl eugenol and basil formulations respectively. The formulations captured a large population of B. dorsalis (99.41%) with an average daily prevalence (FTD) of 10,141 individuals / day / trap and other fruit fly species. Basil powder has the longest persistence (28.67 ± 18.17 days) and basil macerate has the highest weekly catch (513.4 ± 72.34 individuals). The highest average catches were observed with basil macerate (4419 ± 1090 individuals) and methyl eugenol (4899.67 ± 1511.74 individuals). Fresh basil leaf macerate and dry basil leaf powder may be recommended to mango growers in the control of B. dorsalis

    Essai de lutte contre oryctes monoceros olivier (coleoptera : dynastidae) par l’utilisation de l’acide 4-méthyloctanoïque en côte -d’ivoire

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    (Arecaceae), en Côte d’Ivoire. Pour lutter contre ce ravageur, l’acide 4-methyloctanoïque a été initié. Au cours de ces travaux, 3 types de diffuseurs (Da, Db, Dc) contenant les différentes doses ont été expérimentés. L’étude a été menée sur 9 mois repartie sur 4 phases dont 1 mois sans diffuseurs, 4 mois avec diffuseurs, 2 mois retrait desdiffuseurs et 2 mois post diffuseurs. Les visites des cocotiers ont été effectuées 3 fois par semaine avec extraction des insectes des galeries en notant les caractéristiques climatiques et le sexe des insectes. Les diffuseurs ont été pesés au début et chaque mois pendant la phase avec diffuseurs. On note que les trois types de diffuseurs ont la même efficacité contre les attaques de O. monoceros mais le diffuseur Dc, caractérisé par la dose faible, est économiquement plus avantageux et pourrait être vulgarisé auprès des paysans, pour la protection de leurs plantations.Mots clés : Cocos nucifera, Oryctes monoceros, Diffuseurs, Acide 4-méthyloctanoïqueOryctes monoceros Olivier is one of the most dangerous pests of young coconuts Cocos nucifera Linne (Arecaceae) in Côte-d’Ivoire. In order to reduce their populations, 4-methyloctanoïc acid was initiated. In this work, 3 different types of diffusers (Da, Db, Dc) was tested. The study over nine months covered four phases with one month (without diffusers), four month (with diffusers), two month (diffuser withdrawal) and two month (post diffuser). Coconuts were visited 3 twice in a week by collecting insects of galleries and wrote down climatic characteristics, sex of insects. Diffusers were weighted at the beginning and every month during phase with diffusers. We notice that three types of diffusers have the same effectiveness against O. monoceros attacks, diffuser Dc, characterized by a low concentration, is economically more reasonable and could be recommended to the farmer for the protection of their plantations

    Climate Variability in the Sudano-Guinean Transition Area and Its Impact on Vegetation: The Case of the Lamto Region in Côte D’Ivoire

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    Based on unique 50-year datasets from 1962 to 2011, this study diagnoses the variability of climate at Lamto (6.13°N, 5.02°W) in Côte d’Ivoire. A combined pluviothermal index is used to identify climate regions of West Africa. The interdecadal change of the climate is analyzed along with a discussion on the West African Monsoon (WAM) circulation. The impact of vegetation is also analyzed. It is shown that Lamto has mainly a subhumid climate but, in some particular years, this area has a humid climate. Two decades (1962–1971 and 2002–2011) exhibit rainfall excess and the last three ones (1972–1981, 1982–1991, and 1992–2001) show a rainfall deficit that affected West Africa in the early 1970s. The meridional wind field from 1000 hPa to 700 hPa is used to study the WAM variability. The level of the WAM is the lowest (~860–890 hPa) during the active period of the northern wind coming from the Sahara desert (November–February). During 1962–1971 and 2007–2009, the depth of the monsoon at Lamto reaches 300 hPa with an increase in the rainfall. A relationship between potential evapotranspiration and the climate highlights rainfall deficit in 1969 and rainfall excess in 2001–2011

    Caractérisation des sables et morphologie du fond du lac du barrage hydroélectrique de Taabo (Côte d\'Ivoire)

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    Une analyse sédimentologique et minéralogique réalisée sur un cycle hydrologique entre octobre 2004 et août 2005 a permis d\'évaluer les charges solides en suspension et de caractériser les sédiments du lac du barrage de Taabo. La concentration moyenne en matières en suspension (12 mg.L-1) et la turbidité moyenne (20 NTU) montrent que les eaux du lac sont relativement peu chargées. Ces charges en suspension sont composées d\'une fraction inorganique et d\'une fraction organique. Les sables qui composent les sédiments de ce lac sont majoritairement moyens à grossiers et médiocrement classés avec une moyenne granulométrique de 451,48 μm et un indice de classement moyen de 1,13. Les vases et les sables fins occupent les zones profondes du lac et les zones envahies par les végétaux aquatiques. Les sables moyens sont localisés aux voisinages des berges tandis que les sables grossiers sont situés aux voisinages des îles et de la digue. Le cortège minéralogique des sédiments est caractérisé de minéraux lourds (l\'amphibole, la tourmaline, le diopside et l\'épidote) et de minéraux légers (le quartz et les feldspaths). Par ailleurs, cette étude a permis de réaliser la première carte bathymétrique du lac de Taabo 26 ans après sa mise en eau.A sedimentological and mineralogical study carried out on a hydrological cycle from October 2004 to August 2005 has permitted to assess the solid suspended matters and to characterize the sediments of the Taabo dam lake. The average of suspended matters concentration (12 mg.L -1) and the average of turbidity (20 NTU) reveal that the lake is relatively little loaded with suspended matters. These suspended matters are compound of an inorganic fraction and an organic fraction. Sands size in the sediments of this lake are from middle to coarse and badly classified. The grain size average is 451,48 μm; the standard deviation average is 1,13. Muds and fine sands are found in the deeper zones of the lake and also in the zones invaded by the aquatic plants. Middle sands are located near banks while coarse sands are located aside the islands and the dam. The minerals found in the sediments are characterized by heavy minerals (the amphibole, tourmaline, diopside and epidote) and light minerals (quartz and feldspars). Elsewhere, this study has permitted to carry out the first bathymetric Map of this lake 26 years after its setting in water. Keywords: keywordBarrage, lac, granulométrie, minéralogie, bathymétrie, Taabo./Dam, lake, grain size, mineralogy, bathymetry, Taabo.Sciences & Nature Vol. 4 (1) 2007: pp. 93-10

    Distribution of ace-1R and resistance to carbamates and organophosphates in Anopheles gambiae s.s. populations from Côte d'Ivoire

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    <p>Abstract</p> <p>Background</p> <p>The spread of pyrethroid resistance in <it>Anopheles gambiae s.s. </it>is a critical issue for malaria vector control based on the use of insecticide-treated nets. Carbamates and organophosphates insecticides are regarded as alternatives or supplements to pyrethroids used in nets treatment. It is, therefore, essential to investigate on the susceptibility of pyrethroid resistant populations of <it>An. gambiae s.s. </it>to these alternative products.</p> <p>Methods</p> <p>In September 2004, a cross sectional survey was conducted in six localities in Côte d'Ivoire: Toumbokro, Yamoussoukro, Toumodi in the Southern Guinea savannah, Tiassalé in semi-deciduous forest, then Nieky and Abidjan in evergreen forest area. <it>An. gambiae </it>populations from these localities were previously reported to be highly resistant to pyrethroids insecticides. Anopheline larvae were collected from the field and reared to adults. Resistance/susceptibility to carbamates (0.4% carbosulfan, 0.1% propoxur) and organophosphates (0.4% chlorpyrifos-methyl, 1% fenitrothion) was assessed using WHO bioassay test kits for adult mosquitoes. Then, PCR assays were run to determine the molecular forms (M) and (S), as well as phenotypes for insensitive acetylcholinesterase (AChE1) due to G119S mutation.</p> <p>Results</p> <p>Bioassays showed carbamates (carbosulfan and propoxur) resistance in all tested populations of <it>An. gambiae s.s. </it>In addition, two out of the six tested populations (Toumodi and Tiassalé) were also resistant to organophosphates (mortality rates ranged from 29.5% to 93.3%). The M-form was predominant in tested samples (91.8%). M and S molecular forms were sympatric at two localities but no M/S hybrids were detected. The highest proportion of S-form (7.9% of <it>An. gambiae </it>identified) was in sample from Toumbokro, in the southern Guinea savannah. The G119S mutation was found in both M and S molecular forms with frequency from 30.9 to 35.2%.</p> <p>Conclusion</p> <p>This study revealed a wide distribution of insensitive acetylcholinesterase due to the G119S mutation in both M and S molecular forms of the populations of <it>An. gambiae s.s. </it>tested. The low cross-resistance between carbamates and organophosphates highly suggests involvement of other resistance mechanisms such as metabolic detoxification or F290V mutation.</p

    Nicotinamide Deficiency in Primary Open-Angle Glaucoma

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    Purpose: To investigate the plasma concentration of nicotinamide in primary open-angle glaucoma (POAG). Methods: Plasma of 34 POAG individuals was compared to that of 30 age- and sex-matched controls using a semiquantitative method based on liquid chromatography coupled to high-resolution mass spectrometry. Subsequently, an independent quantitative method, based on liquid chromatography coupled to mass spectrometry, was used to assess nicotinamide concentration in the plasma from the same initial cohort and from a replicative cohort of 20 POAG individuals and 15 controls. Results: Using the semiquantitative method, the plasma nicotinamide concentration was significantly lower in the initial cohort of POAG individuals compared to controls and further confirmed in the same cohort, using the targeted quantitative method, with mean concentrations of 0.14 μM (median: 0.12 μM; range, 0.06-0.28 μM) in the POAG group (-30%; P = 0.022) and 0.19 μM (median: 0.18 μM; range, 0.08-0.47 μM) in the control group. The quantitative dosage also disclosed a significantly lower plasma nicotinamide concentration (-33%; P = 0.011) in the replicative cohort with mean concentrations of 0.14 μM (median: 0.14 μM; range, 0.09-0.25 μM) in the POAG group, and 0.19 μM (median: 0.21 μM; range, 0.09-0.26 μM) in the control group. Conclusions: Glaucoma is associated with lower plasmatic nicotinamide levels, compared to controls, suggesting that nicotinamide supplementation might become a future therapeutic strategy. Further studies are needed, in larger cohorts, to confirm these preliminary findings

    Parasite

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    Parasites and infectious diseases are well-known threats to primate populations. The main objective of this study was to provide baseline data on fecal parasites in the cercopithecid monkeys inhabiting Côte d'Ivoire's Taï National Park. Seven of eight cercopithecid species present in the park were sampled: Cercopithecus diana, Cercopithecus campbelli, Cercopithecus petaurista, Procolobus badius, Procolobus verus, Colobus polykomos, and Cercocebus atys. We collected 3142 monkey stool samples between November 2009 and December 2010. Stool samples were processed by direct wet mount examination, formalin-ethyl acetate concentration, and MIF (merthiolate, iodine, formalin) concentration methods. Slides were examined under microscope and parasite identification was based on the morphology of cysts, eggs, and adult worms. A total of 23 species of parasites was recovered including 9 protozoa (Entamoeba coli, Entamoeba histolytica/dispar, Entamoeba hartmanni, Endolimax nana, Iodamoeba butschlii, Chilomastix mesnili, Giardia sp., Balantidium coli, and Blastocystis sp.), 13 nematodes (Oesophagostomum sp., Ancylostoma sp., Anatrichosoma sp., Capillariidae Gen. sp. 1, Capillariidae Gen. sp. 2, Chitwoodspirura sp., Subulura sp., spirurids [cf Protospirura muricola], Ternidens sp., Strongyloides sp., Trichostrongylus sp., and Trichuris sp.), and 1 trematode (Dicrocoelium sp.). Diversity indices and parasite richness were high for all monkey taxa, but C. diana, C. petaurista, C. atys, and C. campbelli exhibited a greater diversity of parasite species and a more equitable distribution. The parasitological data reported are the first available for these cercopithecid species within Taï National Park. Les maladies parasitaires et infectieuses sont des menaces très connues pour les populations de primates. L’objectif principal de cette étude était de fournir des données de base sur les parasites intestinaux des primates non-humains du Parc National de Taï en Côte d’Ivoire. Sept des huit espèces de cercopithécidés vivant dans le parc ont été échantillonnées : Cercopithecus diana, Cercopithecus campbelli, Cercopithecus petaurista, Procolobus badius, Procolobus verus, Colobus polykomos and Cercocebus atys. Nous avons collecté 3142 échantillons de selles de singes de novembre 2009 à décembre 2010. Les échantillons de selles ont été traités par la technique d’examen direct, les méthodes de concentration formol-éthyl acétate et MIF (merthiolate, iode, formol). Les lames ont été examinées au microscope et l’identification des parasites a été basée sur la morphologie des kystes, des œufs et des vers adultes. Au total, 23 espèces de parasites ont été trouvées, dont 9 protozoaires (Entamoeba coli, Entamoeba histolytica/dispar, Entamoeba hartmanni, Endolimax nana, Iodamoeba butschlii, Chilomastix mesnili, Giardia sp., Balantidium coli et Blastocystis sp.), 13 nématodes (Oesophagostomum sp., Ancylostoma sp., Anatrichosoma sp., Capillariidae Gen. sp. 1, Capillariidae Gen. sp. 2, Chitwoodspirura sp., Subulura sp., Spiruridae [cf. Protospirura muricola], Ternidens sp., Strongyloides sp., Trichostrongylus sp. et Trichuris sp.), et un trématode (Dicrocoelium sp.). L’indice de diversité et la richesse parasitaire étaient élevés pour tous les taxa de singes, mais C. diana, C. petaurista, C. atys and C. campbelli ont enregistré une plus grande diversité et une distribution plus équitable des espèces de parasites. Les données parasitologiques que nous rapportons sont les premières disponibles pour ces espèces de singes du Parc National de Taï

    Genomic Selection for Fruit Quality Traits in Apple (Malus×domestica Borkh.)

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    The genome sequence of apple (Malus×domestica Borkh.) was published more than a year ago, which helped develop an 8K SNP chip to assist in implementing genomic selection (GS). In apple breeding programmes, GS can be used to obtain genomic breeding values (GEBV) for choosing next-generation parents or selections for further testing as potential commercial cultivars at a very early stage. Thus GS has the potential to accelerate breeding efficiency significantly because of decreased generation interval or increased selection intensity. We evaluated the accuracy of GS in a population of 1120 seedlings generated from a factorial mating design of four females and two male parents. All seedlings were genotyped using an Illumina Infinium chip comprising 8,000 single nucleotide polymorphisms (SNPs), and were phenotyped for various fruit quality traits. Random-regression best liner unbiased prediction (RR-BLUP) and the Bayesian LASSO method were used to obtain GEBV, and compared using a cross-validation approach for their accuracy to predict unobserved BLUP-BV. Accuracies were very similar for both methods, varying from 0.70 to 0.90 for various fruit quality traits. The selection response per unit time using GS compared with the traditional BLUP-based selection were very high (>100%) especially for low-heritability traits. Genome-wide average estimated linkage disequilibrium (LD) between adjacent SNPs was 0.32, with a relatively slow decay of LD in the long range (r2 = 0.33 and 0.19 at 100 kb and 1,000 kb respectively), contributing to the higher accuracy of GS. Distribution of estimated SNP effects revealed involvement of large effect genes with likely pleiotropic effects. These results demonstrated that genomic selection is a credible alternative to conventional selection for fruit quality traits
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