Effets de fertilisants organique et organomineral a base de dechets vegetaux et animaux sur la croissance et le rendement du soja (Glycine max (L.) Merrill) en zone de savane de Cote d’Ivoire

La culture du soja, en Côte d’Ivoire, n’occupe pas la place qu’elle mérite malgré ses potentialités bénéfiques et les conditions favorables. Aussi, la fertilisation minérale, aux apports certains à la culture, demeure-t-elle coûteuse et inaccessible aux petits paysans. Cette étude vise à évaluer les effets de fertilisants organique et organo-minéral d’origines végétale et animale sur la croissance et le rendement du soja (Glycine max (L.) Merr). Le dispositif expérimental utilisé est un bloc de Fisher randomisé, avec quatre répétitions et quatre traitements que sont le témoin, la fumure minérale, la fumure organique et la fumure organo-minérale. La fumure minérale a été appliquée à des doses de 24 kg ha-1 N, 45 kg ha-1 P2O5 et 36 kg ha-1 K2O. La dose des fumures organique et organo-minérale était de 10 t ha-1. La fumure minérale a permis d’obtenir une meilleure croissance des plants durant les quarante-cinq premiers jours du cycle cultural. Pendant les quarante-cinq derniers jours du cycle, la fumure organo-minérale a eu les meilleurs effets. La fumure organique a, quant à elle, impacté favorablement le nombre de gousses (250) et la masse de 1000 graines (112,25 g). Cependant, le rendement en graines le plus élevé a été obtenu dans le traitement témoin (1,06 t ha-1). Ainsi, l’utilisation de fumure organo-minérale ne semble pas nécessaire pour la culture du soja, mais plutôt la fumure organique en cas de déficience du sol en matière organique, tout en comblant le déficit hydrique pendant la phase de production.Mots clés: fumure organique, fumure organo-minérale, croissance, rendement, soja, Côte d’IvoireEnglish Title: Effects of organic and organo-mineral fertilizers on soybean productivity in the savanna zone of Côte d’IvoireEnglish AbstractSoybean cultivation, in Côte d’Ivoire, is lagging despite its beneficial potential and favorable conditions. Also, the mineral fertilization remains expensive and inaccessible to small farmers. This study aims to evaluate the effects of organic and organo-mineral manure of vegetable and animal origins on the soybean growth and yield (Glycine max (L.) Merr). The experimental design used is a randomized Fisher block with four replicates and four treatments, namely control, mineral manure, organic manure and organo-mineral manure. The mineral manure was applied at doses of 24 kg ha-1 N, 45 kg ha-1 P2O5 and 36 kg ha-1 K2O. The dose of organic and organo-mineral manure was 10 t ha-1. The mineral manure allowed to obtain a better growth of plants during the first forty five days of the cultural cycle. During the last forty five days of the cycle, the organo-mineral manure had the best effects. The organic manure impacted favorably on the number of pods (250) and the mass of 1000 seeds (112,25 g). However, the highest seed yield was obtained in the control treatment (1.06 t ha-1). Thus, the use of organo-mineral manure does not seem necessary for the culture of the soybean, but  rather the organic manure in case of soil deficiency in organic matter, while covering the hydrous deficit during the production phase.Keywords: organic manure, organo-mineral manure, growth, yield, soybean, Côte d’Ivoire

Antibacterial activity of the aqueous extract of Thonningia sanguinea against Extended-Spectrum-b-Lactamases (ESBL) producing Escherichia coli and Klebsiella pneumoniae strains

Purpose: The aim of this study was to evaluate the antimicrobial activity of Thonningia sanguinea against two sensitive and two multi-drug resistant (ESBL) Enterobacteria strains namely Escherichia coli and Klebsiella pneumoniae. Method: The confirmation of the ESBL producing strains was done by the double-disc synergy tests and the broth dilution method was used for the determination of the antimicrobial parameters (MIC and MBC) on these sensitive and ESBL producing strains. Results: The two sensitive strains had the same MIC and MBC values respectively 3.125 mg /ml and 12.50 mg/ml. The ESBL producing strains also had the same MIC of 6.25 mg /ml and MBC values of 25 mg/ml. The extract was bactericidal for all tested strains. Conclusion: The results suggest that the flowers of T. sanguinea can be used in association with antibiotics for alternative therapy of diseases caused by ESBL producing E. coli, Klebsiella pneumoniae. Keywords: Antimicrobial activity, Thonningia sanguinea, ESBL producing strains; E. coli > Tropical Journal of Pharmaceutical Research Vol. 6 (3) 2007: pp. 779-78

Caracterisation des debits d’etiage dans un contexte de changements climatiques : Cas du bassin versant du N'zi (Cote d’Ivoire)

Dans un contexte où les pressions exercées sur les milieux aquatiques et les besoins en eaux des populations ne cessent d’augmenter auquel s’ajoutent les impacts des changements globaux, la connaissance des débits d’étiage constitue un enjeu majeur. L’objectif de cette étude est de caractériser les débits d’étiage du bassin versant du N’zi-Bandama dans l’optique d’une meilleure gestion des ressources en eau de ce bassin. Des données de débits mensuels provenant de cinq stations hydrométriques du fleuve N’zi-Bandama (Fétékro, M’bahiakro, Bocanda, Dimbokro, N’zianouan) ont été utilisées et couvrent la période allant de 1960 à 2016. La méthodologie a consisté à calculer et analyser les seuils de sévérité d’étiage (seuil d’alerte ou QMNA-5, seuil de vigilance et seuil de crise). Les quantiles de débits d’étiage ont été déterminés à partir de la loi lognormale correspondant aux périodes de retour 2, 5, 10, 20 et 50 ans. Les principaux résultats obtenus ont montré que les débits de seuils de sévérité déterminés mettent en évidence la vulnérabilité à de sévères étiages du bassin versant du N’zi-Bandama avec une exposition à la vulnérabilité plus forte pour le sous-bassin versant d’exutoire Fétékro.Mots clés: Débits d’étiage ; QMNA ; Seuils de sévérité ; Bassin versant du N’zi ; Côte d’Ivoire

Long-term continuous administration of a hydro-ethanolic extract of Synedrella nodiflora (L) Gaertn in male Sprague-Dawley rats: biochemical, haematological and histopathological changes

Background: Conflicting reports about the toxicity of Synedrella nodiflora (L) Gaertn (family Asteraceae), a plant traditionally used in Ghana for the management of epilepsy, abound in literature. The present study evaluates the effect of a 90-day continuous oral administration of a hydro-ethanolic whole plant extract of Synedrella nodiflora (SNE) in male Sprague-Dawley rats.Methods: The toxicological evaluation of the extract (100, 300 and 1000 mgkg-1) was focused on haematological, serum biochemical parameters and histopathological changes of some isolated organs.Results: The extract produced no mortality in the rats treated during the study period. Only SNE 100 mgkg-1 produced significant decrease in white blood cell and neutrophil counts and an increase in albumin, globulin, total bilirubin, total protein and potassium levels. The higher doses (SNE 300 and 1000 mgkg-1) had no significant effect on all the haematological and biochemical parameters measured. Histopathological assessment of the liver, kidney and heart revealed no abnormalities in rats treated with the extracts. Only the SNE 1000 mgkg-1 produced distortions of the branching arrangements of the myocardial fibres and a congested vessel which indicates a healed infarction.Conclusions: The findings suggest hydro-ethanolic extract of Synedrella nodiflora (L) Gaertn generally has a low toxicity profile following a 90-day continuous oral administration in male Sprague-Dawley rats under the present laboratory conditions. However patients with renal or cardiac problems should use the plant with caution.Funding: Jointly supported by the International Foundation for Science, Stockholm, Sweden, through a grant (# F/5191-1) to Dr. Patrick Amoateng and the Office of Research, Innovation and Development (ORID), University of Ghana, Accra, Ghana, grant awarded to Dr. Patrick Amoateng (reference number: URF/6/ILG-002/2012-2013)Keywords: : Synedrella nodiflora, Sprague-Dawley rats, histopathological, haematologica

Technical Basis for Assessing Uranium Bioremediation Performance

In situ bioremediation of uranium holds significant promise for effective stabilization of U(VI) from groundwater at reduced cost compared to conventional pump and treat. This promise is unlikely to be realized unless researchers and practitioners successfully predict and demonstrate the long-term effectiveness of uranium bioremediation protocols. Field research to date has focused on both proof of principle and a mechanistic level of understanding. Current practice typically involves an engineering approach using proprietary amendments that focuses mainly on monitoring U(VI) concentration for a limited time period. Given the complexity of uranium biogeochemistry and uranium secondary minerals, and the lack of documented case studies, a systematic monitoring approach using multiple performance indicators is needed. This document provides an overview of uranium bioremediation, summarizes design considerations, and identifies and prioritizes field performance indicators for the application of uranium bioremediation. The performance indicators provided as part of this document are based on current biogeochemical understanding of uranium and will enable practitioners to monitor the performance of their system and make a strong case to clients, regulators, and the public that the future performance of the system can be assured and changes in performance addressed as needed. The performance indicators established by this document and the information gained by using these indicators do add to the cost of uranium bioremediation. However, they are vital to the long-term success of the application of uranium bioremediation and provide a significant assurance that regulatory goals will be met. The document also emphasizes the need for systematic development of key information from bench scale tests and pilot scales tests prior to full-scale implementation

Entomological Surveillance of Behavioural Resilience and Resistance in Residual Malaria Vector Populations.

The most potent malaria vectors rely heavily upon human blood so they are vulnerable to attack with insecticide-treated nets (ITNs) and indoor residual spraying (IRS) within houses. Mosquito taxa that can avoid feeding or resting indoors, or by obtaining blood from animals, mediate a growing proportion of the dwindling transmission that persists as ITNs and IRS are scaled up. Increasing frequency of behavioural evasion traits within persisting residual vector systems usually reflect the successful suppression of the most potent and vulnerable vector taxa by IRS or ITNs, rather than their failure. Many of the commonly observed changes in mosquito behavioural patterns following intervention scale-up may well be explained by modified taxonomic composition and expression of phenotypically plastic behavioural preferences, rather than altered innate preferences of individuals or populations. Detailed review of the contemporary evidence base does not yet provide any clear-cut example of true behavioural resistance and is, therefore, consistent with the hypothesis presented. Caution should be exercised before over-interpreting most existing reports of increased frequency of behavioural traits which enable mosquitoes to evade fatal contact with insecticides: this may simply be the result of suppressing the most behaviourally vulnerable of the vector taxa that constituted the original transmission system. Mosquito taxa which have always exhibited such evasive traits may be more accurately described as behaviourally resilient, rather than resistant. Ongoing national or regional entomological monitoring surveys of physiological susceptibility to insecticides should be supplemented with biologically and epidemiologically meaningfully estimates of malaria vector population dynamics and the behavioural phenotypes that determine intervention impact, in order to design, select, evaluate and optimize the implementation of vector control measures

Negative Cross Resistance Mediated by Co-treated bed nets: A Potential Means of Restoring Pyrethroid-susceptibility to Malaria Vectors.

Insecticide-treated nets and indoor residual spray programs for malaria control are entirely dependent on pyrethroid insecticides. The ubiquitous exposure of Anopheles mosquitoes to this chemistry has selected for resistance in a number of populations. This threatens the sustainability of our most effective interventions but no operationally practicable way of resolving the problem currently exists. One innovative solution involves the co-application of a powerful chemosterilant (pyriproxyfen or PPF) to bed nets that are usually treated only with pyrethroids. Resistant mosquitoes that are unaffected by the pyrethroid component of a PPF/pyrethroid co-treatment remain vulnerable to PPF. There is a differential impact of PPF on pyrethroid-resistant and susceptible mosquitoes that is modulated by the mosquito's behavioural response at co-treated surfaces. This imposes a specific fitness cost on pyrethroid-resistant phenotypes and can reverse selection. The concept is demonstrated using a mathematical model

Semi-field studies to better understand the impact of eave tubes on mosquito mortality and behaviour

Background: Eave tubes are a type of housing modification that provide a novel way of delivering insecticides to mosquitoes as they attempt to enter the house. The current study reports on a series of semi-field studies aimed at improving the understanding of how eave tubes might impact mosquito mortality and behaviour. Methods: Experiments were conducted using West African style experimental huts at a field site in M'be, Côte d'Ivoire. Huts were modified in various ways to determine: (i) whether mosquitoes in this field setting naturally recruit to eave tubes; (ii) whether eave tubes can reduce house entry even in the absence of screening; (iii) whether mosquitoes suffer mortality if they attempt to exit a house via treated eave tubes; and, (iv) whether screening and eave tubes might deflect mosquitoes into neighbouring houses without the intervention. Results: Ninety percent more mosquitoes (Anopheles gambiae sensu lato, and other species) entered huts through open eaves tubes compared to window slits. The addition of insecticide-treated eave tubes reduced mosquito entry by 60%, even when windows remained open. Those mosquitoes that managed to enter the huts exhibited a 64% reduction in blood feeding and a tendency for increased mortality, suggesting contact with insecticide-treated inserts prior to hut entry. When An. gambiae mosquitoes were deliberately introduced into huts with treated eave tubes, there was evidence of six times increase in overnight mortality, suggesting mosquitoes can contact treated eave tube inserts when trying to exit the hut. There was no evidence for deflection of mosquitoes from huts with screening, or screening plus eave tubes, to adjacent unmodified huts. Conclusions: Eave tubes are a potentially effective way to target Anopheles mosquitoes with insecticides. That treated eave tubes can reduce mosquito entry even when windows are open is a potentially important result as it suggests that eave tubes might not need to be combined with household screening to have an impact on malaria transmission. The absence of deflection is also a potentially important result as coverage of eave tubes and/or screening is unlikely to be 100% and it is important that households that do not have the technology are not disadvantaged by those that do

An overview of anti-diabetic plants used in Gabon: Pharmacology and Toxicology

© 2017 Elsevier B.V. All rights reserved.Ethnopharmacological relevance: The management of diabetes mellitus management in African communities, especially in Gabon, is not well established as more than 60% of population rely on traditional treatments as primary healthcare. The aim of this review was to collect and present the scientific evidence for the use of medicinal plants that are in currect by Gabonese traditional healers to manage diabetes or hyperglycaemia based here on the pharmacological and toxicological profiles of plants with anti-diabetic activity. There are presented in order to promote their therapeutic value, ensure a safer use by population and provide some bases for further study on high potential plants reviewed. Materials and methods: Ethnobotanical studies were sourced using databases such as Online Wiley library, Pubmed, Google Scholar, PROTA, books and unpublished data including Ph.D. and Master thesis, African and Asian journals. Keywords including ‘Diabetes’ ‘Gabon’ ‘Toxicity’ ‘Constituents’ ‘hyperglycaemia’ were used. Results: A total of 69 plants currently used in Gabon with potential anti-diabetic activity have been identified in the literature, all of which have been used in in vivo or in vitro studies. Most of the plants have been studied in human or animal models for their ability to reduce blood glucose, stimulate insulin secretion or inhibit carbohydrates enzymes. Active substances have been identified in 12 out of 69 plants outlined in this review, these include Allium cepa and Tabernanthe iboga. Only eight plants have their active substances tested for anti-diabetic activity and are suitables for further investigation. Toxicological data is scarce and is dose-related to the functional parameters of major organs such as kidney and liver. Conclusion: An in-depth understanding on the pharmacology and toxicology of Gabonese anti-diabetic plants is lacking yet there is a great scope for new treatments. With further research, the use of Gabonese anti-diabetic plants is important to ensure the safety of the diabetic patients in Gabon.Peer reviewedFinal Accepted Versio