78 research outputs found

    Caractérisations morphologique et génétique d’espèces d’aleurodes prélevées dans les cultures de tomate atteinte de la virose du TYLC, dans la zone des Niayes au Sénégal

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    Les aleurodes sont vecteurs de plusieurs virus dont celui du jaunissement et de l’enroulement des feuilles de tomate (Solanum lycopersicum L.) appelé Tomato Yellow Leaf Curl Virus (TYLCV). L’objectif de ce travail était d’identifier les différentes espèces d’aleurodes présentes dans les cultures de tomate de la zone des Niayes en rapport avec le TYLC. Des puparia et des adultes ont été récoltés sur les feuilles de la variété « Xina », atteintes du TYLC pour des caractérisations morphologique et génétique. La méthode d’analyse du Ministère français de l’Agriculture a été utilisée pour leur montage et leur identification. Pour six spécimens, l’échantillon le plus proche sur Q-bank et Genbank était un aleurode identifié comme Bemisia tabaci avec une similarité de 75 à 98%. Pour les deux autres, l’aleurode le plus proche dans Q-bank était B. afer avec une similarité de 77 à 78%, et dans Genbank B. tabaci avec 77%. Cinq autres ont été identifiés comme Aleurodicus. Leurs séquences du gène CO1 sont identiques. Les 11 spécimens identifiés dans Q-Bank comme Aleurodicus dispersus sont identiques à 100% à aux spécimens du Sénégal. Au total, l’étude a mis en évidence deux espèces différentes de Bemisia (B. tabaci et B. afer) et Aleurodicus dispersus.© 2016 International Formulae Group. All rights reserved.Mots clés: TYLCV, Bemisia spp, virus, Puparium, séquencesEnglish Title: Morphological and genetic characterizations of whiteflies species sampled from tomato infected by tomato yellow leaf virus disease in Niayes area of SenegalEnglish AbstractWhiteflies are vectors of many viral diseases including tomato (Solanum lycopersicum L.) curling i.e. Tomato Yellow Leaf Curl Virus (TYLCV). This work aimed at identifying different whitefly species on tomatoes in relation to the TYLCV in Niayes areas Puparia and adults were collected from "Xina" tomato variety leaves showing TYLC symptoms for both morphological and genetic characterizations. The French Ministry of agriculture analysis method was used for their preparation and identification. For six specimens,  the most similar sample on Q-bank and Genbank was identified as Bemisia tabaci with a similarity ranging between 75 and 98%. Two others were closest to Bemisia afer on Q-bank with a similarity of 77 to 78%, and Bemisia tabaci on Genbank with a similarity of 77%. Five others were identified as Aleurodicus. Their CO1 gene sequences were similar. The 11 specimens identified as Aleurodicus dispersus with a 100% similarity to specimens from Senegal. Overall, this study came out with two different species of Bemisia (B. tabaci et B. afer) and Aleurodicus dispersus.© 2016 International Formulae Group. All rights reserved.Keywords: TYLCV, Bemisia spp, virus, Puparium, sequence

    SYNTHESIS AND INFRARED STUDY OF SOME PHENYLPHOSPHONATE, DIPHENYLPHOSPHINATE AND ACETATOPHOSPHONATE NEW ORGANOTIN (IV) DERIVATIVES AND ADDUCTS

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    Three organotin (IV) derivatives PhPO3HSnBu2Cl, SnBu2Ph2PO2ClĂ—3/2H2O, Sn(PhPO3)Cl2Ă—2H2O obtained on allowing PhPO3H2 or propylammonium PhPO3H to react with SnBu2Cl2, SnCl2Ă—2H2O and two adducts [(C6H5CH2)2NH2]3O2C(CH2)2PO3Ă—3SnPh3Cl, [CyNH3(HO2POCH2-N(CH2CO2H)2]2Ă—3SnCl4.2H2OĂ—NH4Cl obtained on allowing (C6H5CH2)NH2)3O2C(CH2)2PO3 or [CyNH3(HO2POCH2-N(CH2 CO2H)2]2 and SnPh3Cl or SnCl2Ă—2H2O to react in ethanolic media have been characterized by elemental analyses, infrared and Mossbauer techniques. The suggested structures, while considering the anionic counterpart, are discrete, dimeric, double and triple metallic components or of infinite chain types, the anion behaving as a monochelating, a bichelating or a bidentate ligand. In OH containing structures, when extra hydrogen bonds are considered, supramolecular architectures may be obtained

    NEW TETRANUCLEAR AND MONONUCLEAR OXALATO ORGANOTIN (IV) COMPLEXES WITH MONOCYCLOHEXYLAMMONIUM AS ADVERSE CATION: SYNTHESIS AND INFRARED STUDY

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    Eight new adducts and derivatives have been synthesized and studied by infrared. Discrete, layered or infinite chain structures are suggested with an oxalate behaving as a monodentate, bidentate, monochelating or bichelating ligand, the environment around the tin centres being tetrahedral, cis trigonal bipyramidal or octahedral. In all the studied compounds, supramolecular architectures may be obtained when intermolecular hydrogen bonds are considered

    SYNTHESIS AND INFRARED STUDY OF SOME PHENYLPHOSPHONATE, DIPHENYLPHOSPHINATE AND ACETATOPHOSPHONATE NEW ORGANOTIN (IV) DERIVATIVES AND ADDUCTS

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    Three organotin (IV) derivatives PhPO3HSnBu2Cl, SnBu2Ph2PO2ClĂ—3/2H2O, Sn(PhPO3)Cl2Ă—2H2O obtained on allowing PhPO3H2 or propylammonium PhPO3H to react with SnBu2Cl2, SnCl2Ă—2H2O and two adducts [(C6H5CH2)2NH2]3O2C(CH2)2PO3Ă—3SnPh3Cl, [CyNH3(HO2POCH2-N(CH2CO2H)2]2Ă—3SnCl4.2H2OĂ—NH4Cl obtained on allowing (C6H5CH2)NH2)3O2C(CH2)2PO3 or [CyNH3(HO2POCH2-N(CH2 CO2H)2]2 and SnPh3Cl or SnCl2Ă—2H2O to react in ethanolic media have been characterized by elemental analyses, infrared and Mossbauer techniques. The suggested structures, while considering the anionic counterpart, are discrete, dimeric, double and triple metallic components or of infinite chain types, the anion behaving as a monochelating, a bichelating or a bidentate ligand. In OH containing structures, when extra hydrogen bonds are considered, supramolecular architectures may be obtained

    Utilisation de paramètres bioécologiques pour analyser la biodiversité ichtyologique de l’Aire Marine Protégée (AMP) de Joal-Fadiouthau Sénégal et sa périphérie non protégée à la pêche

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    With global changes, concerns about marine ecosystems and population dynamics are of increasing interest to researchers. As such, knowledge of the specific biodiversity of exploited marine ecosystems is generally considered a key factor in their resilience. This paper is a comparative study that focuses on analyzing the bioecological effects of MPA Joal-Fadiouth on fish populations by comparing the inside vs. outside of the MPA. Data were collected from scientific surveys conducted in cold and hot seasons in 2015. In each survey, 16 stations were sampled; 9 inside the MPA and 7 outside. The MPA is in open Ocean and the analysis of environmental parameters shows that the MPA area is a homogeneous environment. The variability is at the seasonal level. This variability is similar inside and outside the MPA. A total of 67 species in 37 families were found in the reserve, against 41 species in 32 families outside MPA. The biological indicators analysis shows a similar species richness and biomass between the two areas. However, total abundance is higher in the protected area. On the other hand, larger fish are more likely to be outside the protected area. In the MPA, 20 species sampled are in spawning period, but over 80 % of individuals are immature. The Joal-Fadiouth MPA implementation significantly improves the conservation of biodiversity with a dominance of herbivorous species and lower trophic levels. In addition, the reserve is a nursery area for many species (sardines, octopus, and shrimp) and reproduction for some species characteristics of the area, e.g.Hemiramphus brasiliensis and Stephanolepis hispidus

    NEW TETRANUCLEAR AND MONONUCLEAR OXALATO ORGANOTIN (IV) COMPLEXES WITH MONOCYCLOHEXYLAMMONIUM AS ADVERSE CATION: SYNTHESIS AND INFRARED STUDY

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    Eight new adducts and derivatives have been synthesized and studied by infrared. Discrete, layered or infinite chain structures are suggested with an oxalate behaving as a monodentate, bidentate, monochelating or bichelating ligand, the environment around the tin centres being tetrahedral, cis trigonal bipyramidal or octahedral. In all the studied compounds, supramolecular architectures may be obtained when intermolecular hydrogen bonds are considered

    Étude comparative des peuplements ichtyologiques de l’Aire Marine Protégée de Joal-Fadiouth et des pêcheries des zones du pourtour non protégées à l’exploitation halieutique

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    L'effondrement des stocks de poisson est dĂ» Ă  la surexploitation des peuplements ichtyologiques consĂ©cutifs aux mauvaises pratiques de pĂŞche au SĂ©nĂ©gal. Cette situation a amenĂ© les Ă©cologistes marins et les gestionnaires de l'environnement Ă  rĂ©Ă©valuer les mĂ©thodes traditionnelles de gestion des ressources halieutiques. Pour connaitre la dynamique des peuplements ichtyologiques, nous avons menĂ© une Ă©tude comparative des peuplements ichtyologiques de l’Aire Marine ProtĂ©gĂ©e de Jaol-Fadiouth et des pĂŞcheries des zones non protĂ©gĂ©es Ă  l’exploitation halieutique durant la saison froide 2015. Ainsi, l’exploitation des donnĂ©es de pĂŞches expĂ©rimentales rĂ©alisĂ©es au niveau de 16 stations dans les deux zones a permis de faire l’étude. L’analyse des paramètres environnementaux relevĂ©s sur chaque station montre que la zone de l’aire marine protĂ©gĂ©e est similaire Ă  celle des zones non protĂ©gĂ©es Ă  l’exploitation halieutique. Par consĂ©quent, les Ă©ventuelles diffĂ©rences de peuplement ne s'expliquent pas par la variabilitĂ© des paramètres physicochimiques. L’analyse de paramètres physico-chimiques, des indicateurs de biodiversitĂ© Ă  savoir : la richesse spĂ©cifique, les indices de diversitĂ© de Shannon-Weaver et d’équitabilitĂ© Pielou ont permis de dĂ©terminer les caractĂ©ristiques environnementales, la composition et la nature des peuplements, d'Ă©valuer l'impact des mesures de gestion des diffĂ©rentes zones.   The collapse of fish stocks is due to the overexploitation of fish populations as a result of poor fishing practices in Senegal. This situation has led marine ecologists and environmental managers to re-evaluate traditional methods of managing fishery resources. In order to know the dynamics of the ichthyological populations, we conducted a comparative study of the ichthyological populations of the Jaol-Fadiouth Marine Protected Area and the fisheries of the areas not protected from fishing during the 2015 cold season. Thus, the exploitation of data from experimental fisheries carried out at 16 stations in the two areas allowed the study to be carried out. The analysis of the environmental parameters recorded at each station shows that the area of the marine protected area is similar to that of the areas not protected from fisheries exploitation. Therefore, any differences in population size cannot be explained by the variability of physico-chemical parameters. The analysis of physico-chemical parameters, biodiversity indicators such as species richness, the Shannon-Weaver diversity index and the Pielou equitability index allowed us to determine the environmental characteristics, the composition and the nature of the populations, and to evaluate the impact of the management measures of the different areas

    Production d’alevins de Tilapia (Oreochromis niloticus) avec 3 aliments à base de sous-produits agro-industriels au Nord du Sénégal

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    L’étude a été réalisée dans un étang de la station piscicole de Richard TOLL au Nord du Sénégal entre 2013 et 2014. Elle a permis de tester la performance de deux aliments à base de sous-produits agro industriels locaux (A1 et A2) à un aliment (A3) importé de la Chine sur la croissance des alevins de tilapia (Oreochromis niloticus) du fleuve Sénégal. Les qualités nutritionnelles des aliments A1, A2 et A3 sur la croissance et le taux de mortalités des alevins sont déterminés pour chaque aliment. La méthodologie est accentuée sur la mesure des paramètres physico-chimiques, le suivi de la croissance des alevins et le test en triplicata de ces trois aliments dans des appas de 2m3. Les résultats obtenus ont montré que l’aliment A2 a donné les meilleures performances que l’aliment A1 avec des croissances moyennes individuelles respectives de 0,21±0,04g/j et 0,12±0,03g/j. Les gains de poids moyens et taux de conversion alimentaire sont respectivement 3,09±0,53g et 1,79±0,26 g pour l’aliment A2 et 1,82±0,45g et 1,64±0,01 g pour l’aliment A1. Statistiquement, les résultats obtenus avec l’aliment A2 ne sont pas différents de ceux obtenus avec l’aliment A3 importé de la Chine.© 2015 International Formulae Group. All rights reserved.Mots clés: Alevins, Oreochromis niloticus, aliment, croissance, performanceEnglish Title:  Production of young Tilapia fish (Oreochromis niloticus) with 3 foods containing under agroindustrial products in the North of SenegalEnglish AbstractThe study was carried out in a pond of the piscicultural station of Richard-TOLL in the North of Senegal between 2013 and 2014. It allowed to test the performance of two food containing local agro industrial by-products (A1 and A2) with a food (A3) imported from China for the growth of young tilapias fish (Oreochromis niloticus) of the Senegal river. Nutritional qualities of the food A1, A2 and A3 on the growth and the death rate of young fish were given for each food. The methodology emphasized on the measure of the physicochemical parameters, the follow-up of the growth of young fish and the test in triplicate of these three food in grabbed of 2 m3.The results obtained showed that A2 food gave the best performances than A1 food with the respective average individual growths of 0, 21±0,04 g/j and 0,12±0,03 g/j. The mean gain of weight and food conversion rate are respectively 3,09±0,53 G and 1,79±0,26 G for A2 food and 1,82±0,45 G and  1,64±0,01 G for A1 food. Statistically analysed, the results obtained with the A2 food are not different from those obtained with the A3 food imported from China.© 2015 International Formulae Group. All rights reserved.Keywords: Fry, Oreochromis niloticus, food, growth, performanc

    CRYSTAL STRUCTURE OF TRIPHENYLTIN (IV) FORMATE POLYMER, (HCO2SnPh3)n

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    The title polymer [HCO2Sn(C6H5)3]n was isolated by serendipitous from reaction in ethanol 96 % between bis-(monocyclohexyl ammonium) 2-carboxyethyl hydrogen phosphonate, {(CyNH3)2[CO2CH2CH2PO2(OH)]} and triphenyltin chloride, SnPh3Cl. The polymer crystallizes in the monoclinic space group P21/n with Z = 4, a = 14.7091 (18) Å, b = 15.4133 (19) Å, c = 14.7639 (18) Å, β = 94.242 (2)° and V = 3338.0 (7) Å3. The structure consists of an infinite chain propagating along the crystallographic a-axis direction with bidentate formate anions. The O2SnC3 core is organized into a trans-trigonal bipyramidal like-arrangement

    CRYSTAL STRUCTURE OF TRIPHENYLTIN (IV) FORMATE POLYMER, (HCO2SnPh3)n

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    The title polymer [HCO2Sn(C6H5)3]n was isolated by serendipitous from reaction in ethanol 96 % between bis-(monocyclohexyl ammonium) 2-carboxyethyl hydrogen phosphonate, {(CyNH3)2[CO2CH2CH2PO2(OH)]} and triphenyltin chloride, SnPh3Cl. The polymer crystallizes in the monoclinic space group P21/n with Z = 4, a = 14.7091 (18) Å, b = 15.4133 (19) Å, c = 14.7639 (18) Å, β = 94.242 (2)° and V = 3338.0 (7) Å3. The structure consists of an infinite chain propagating along the crystallographic a-axis direction with bidentate formate anions. The O2SnC3 core is organized into a trans-trigonal bipyramidal like-arrangement
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