Effets de la Dose et Fractionnement de l’Azote Sur l’Acitite d’Un Histosol et le Rendement en Riziculture a Songon (Cote d’Ivoire)

L’azote est indispensable en riziculture alors que la fertilisation azotée est soumise à des pertes en milieu inondé. Elle peut modifier l’acidité du sol tendant à une dégradation des sols et une faible efficience agronomique. C’est pourquoi, la gestion de la fertilisation azotée doit être rationnelle spécialement sur Histosol (tourbe) qui mérite préservation. C’est dans un tel contexte que cette étude a été réalisée pour identifier l’interaction optimale de la dose (0, 80, 100, 120 kg ha-1) et du fractionnement (0, 1, 2, 3 et 4) de l’azote dans un dispositif split-plot à trois (3) répétitions utilisant la variété de riz WITA9. La dose d’azote a eu des effets significatifs (P<0,05) sur le rendement en grain (RDG) du riz et le pH du sol. Un parallélisme a été noté pour les courbes de tendance du pHeau et du RDG permettant d’identifier la dose l’optimal à 80 kg N ha-1 pour le RDG (5,1 t ha-1) et le pH (4,6). Aussi, 4 fractions de la dose ont été meilleures selon l’efficience agronomique. Une régression du pH selon le nombre de fraction de l’azote a permis de prédire 5 fractions comme l’optimale pour le pH (4,8) du sol. La dose 80 kg N ha-1 appliquée en cinq fractions a été recommandée pour une riziculture durable, spécialement sur Histosol.   Nitrogen is essential in rice cultivation while nitrogen fertilization is subjected to losses in a flooded environment. It can modify the soil's acidity toward soil degradation and low agronomic efficiency. Hence, the management of nitrogen fertilization must be rational, especially on Histosol (peat) which deserves preservation. Therefore, this study was carried out to identify the optimal interaction of the dose (0, 80, 100, 120 kg ha-1) and the fractionation (0, 1, 2, 3, and 4) of nitrogen in a split-plot design in three (3) repetitions using the rice variety WITA9. Nitrogen dose had significant effects (P<0.05) on grain yield (RDG) of rice and soil pH. Parallelism was noticed for the trend curves of pHwater and RDG allowing to the identification of the optimal dose at 80 kg N ha-1 for RDG (5.1 t ha-1) and pH (4.6). Also, 4 fractions of the dose were better according to the agronomic efficiency. A regression of the pH according to the number of nitrogen fractions made it possible to predict 5 fractions as the optimum for the pH (4.8) of the soil. The dose of 80 kg N ha-1 applied in five fractions was recommended for sustainable rice cultivation, especially on Histosol

Phytochimie des Extraits de Sida acuta et Evaluation de la Toxicite de l’Extrait Aqueux

Cette étude a pour but d’évaluer la toxicité de l’extrait aqueux de Sida acuta, une plante beaucoup utilisée en médecine traditionnelle par les populations ouest africaine et particulièrement ivoirienne. L’intérêt accordé à la dite étude est dû au besoin de garantir aux populations, une thérapie à base de plante sans risque de toxicité ou d’effet nocif. L’analyse de la phytochimie qualitative a été réalisée par la méthode de coloration en tubes et l’évaluation de la toxicité de l’extrait aqueux sur des souris blanches suivant la ligne Directrice 423 de l’OCDE, modifié en 2008. Les doses 300, 1000, 2000 et 5000 mg/kg de masse corporelle ont été administrées par gavage aux quatre lots expérimentaux. Seul le lot témoin a reçu de l’eau distillée. La phytochimie a révélé simultanément les stéroïdes et terpènes pour l’extrait aqueux et éthanolique 70% tandis que les alcaloïdes, polyphénols, et les flavonoïdes ont été révélés exclusivement dans l’extrait éthanolique 70%. La dose maximale de 5000 mg/kg de masse corporelle n’a enregistré aucun décès. Par conséquent, l’extrait aqueux de Sida acuta  reste sans danger à l’usage par voie orale en médecine traditionnelle.   This study aims to evaluate the toxicity of the aqueous extract of Sida acuta, a plant widely used in traditional medicine by West African and particularly Ivorian populations. The interest given to the said study is due to the need to guarantee populations a plant-based therapy without risk of toxicity or harmful effects. The qualitative phytochemical analysis was carried out by the tube staining method and the evaluation of the toxicity of the aqueous extract on white mice following OECD Guideline 423, modified in 2008. Doses 300, 1000, 2000 and 5000 mg/kg body weight were administered by gavage to the four experimental batches. Only the control batch received distilled water. Phytochemistry simultaneously revealed steroids and terpenes for aqueous and the 70% ethanolic extract while alkaloids, polyphenols, and flavonoids were revealed exclusively in the 70% ethanolic extract. The maximum dose of 5000 mg/kg body weight recorded no deaths. Therefore, the aqueous extract of Sida acuta remains safe for oral use in traditional medicine

Evaluation de la technique de surgreffage pour le rénouvellement des vieillissants vergers d’anacardier [Anacardium occidentale (L.)] dans la région du Gontougo en Côte d’Ivoire

La Côte d’Ivoire est le premier pays producteur et exportateur mondial de noix de cajou. Toutefois, les rendements en noix des vergers ivoiriens demeurent faibles. Ces faibles rendements sont dus à un parc composé de vergers vieillissants, à l’absence de variétés améliorées et à la forte densité des plantations. L’objectif général de la présente étude est de contribuer au renouvellement du verger anarcardier par la technique de surgreffage. Pour y arriver, les arbres de différents âges et peu productifs ont été recepés à différentes hauteurs, différentes circonférences du tronc et sous différents niveaux d’éclaircie. Trois mois après le recépage, des greffons prélevés sur des arbres élites ont été greffés sur les repousses. Les résultats collectés ont montré que les plus jeunes arbres et les arbres plus âgés ont donné les plus courts délais de repousse (30,52 à 33,38 jours). Le nombre de pousses feuillées, la surface foliaire des feuilles émises et le pourcentage de réussite ont été plus importants lorsque les arbres ont été recépés à une hauteur de 140 cm à partir du sol. L’analyse de variance a permis de faire ressortir la différence entre les individus pour chaque facteur étudié. Les arbres de diamètre supérieur à 50 cm ont produit le plus grand nombre de pousses feuillées (32). Selon le niveau de l’éclaircie, les greffons bien eclairés ont été plus vigoureux. Les poids moyens des arbres surgreffés selon les génotypes ont été compris entre 27,5 et 234 g/arbre contre 493 g/arbre pour les arbres en plantation non surgreffés.Côte d'Ivoire is the world's leading producer and exporter of cashew nuts. However, walnut yields in Ivorian orchards remain low. These low yields are due to a park of aging orchards, lack of improved varieties and high density of plantations. The general objective of this study is to contribute to the renewal of the cashew apple orchard by the technique of over grafting To achieve this, trees of different ages and low productivity were received at different heights, different trunk circumferences and under different levels of thinning. Three months after the grafting, grafts taken from elite trees were grafted on the regrowth. The results collected showed that the youngest trees and older trees gave the shortest regrowth (30.52 to 33.38 days). The number of leafy shoots, the leaf area of the leaves emitted and the percentage of success were greater when the trees were retrieved at a height of 140 cm from the ground. . The analysis of variance made it possible to highlight the difference between the individuals for each factor studied. Trees larger than 50 cm produced the largest number of leafy shoots (32). Depending on the level of thinning, the well-lit gryphon was more vigorous. The average weights of the trees grafted according to the genotypes were between 27.5 and 234 g / tree against 493 g / tree for non-grafted plantation trees

Phenotypic and Pathogenic Characterization of Leaf Fungi of Yam (Dioscorea spp) Varieties Grown In Côte D’Ivoire

Yam (Dioscorea spp) occupies an important place in the diet of the populations of Côte d’Ivoire. It is a real source of starch and therefore generates enormous commercial potential. However, the decrease in production due to pest attacks represents a real threat to this crop. This study was conducted with the aim of improving yam production in Côte d’Ivoire. To do so, isolations carried out on yam leaves showing symptoms of foliar diseases have allowed us to identify 9 fungal genera. These were Colletotrichum sp., Fusarium sp., Pestalotiopsis sp., Pestalotia sp., Botryodiplodia sp., Aspergillus sp., Mucor sp., Curvularia sp. and Phytophtora sp. Among these fungi, the genus Colletotrichum sp. was the most isolated with a rate of 56% followed by the Fusarium and Pestalotia genera (8%). Pathogenicity tests performed on healthy leaves of two yam varieties revealed that the Dioscorea alata is more susceptible to fungi compared to Dioscorea rotundata. The largest average diameter of necrosis was caused by Pestalotiopsis sp. (5.97 cm) on the Dioscorea alata variety while the smallest was caused by Colletotrichum sp.9 on Dioscorea rotundata (0.5 cm). Combatting these fungi need to be developed for effective management of leaf diseases of yam in Côte d’Ivoire

EFFETS DU LIT ET DE LA DENSITÉ DE PLANTATION SUR LA CROISSANCE VÉGÉTATIVE DE L’ANANAS (ANANAS COMOSUS L., VAR. MD2) DANS LA LOCALITÉ DE DABOU EN CÔTE D’IVOIRE

The aim of this study was to identify the best planting bed and density for vegetative growth of Ananas comosus L. var. MD2 plants in the locality of Dabou in Côte d’Ivoire. The effects of three planting beds : flat land, ridge without polyethylene film and ridge covered with polyethylene film ; and two planting densities : 50,000 and 70,000 plants/ha (D50 and D70, respectively) were tested through a split-plot disposition. At the end of the vegetative phase of the cycle, growth parameters were evaluated. The results showed that D70, average heights apical bunches were higher (91.52 cm) than D50 (86.87 cm). The number of fresh leaves varied between 48 and 51. The ridge covered with polyethylene film was distinguished with a number of relatively larger fresh leaves. The follow-up of the D leaves biomass revealed that seven months, the value of 70 g required to trigger floral induction therapy (FIT) had been reached in all plants, whatever planting bed and density. The flat land - density 70,000 plants/ha combinaison was illustrated with the D leaves biomass the highest (80.20 g). The weight of the fruit beingrelated to the plant’s growth during the floral induction therapy, at the end of the vegetative phase, the results could contribute to improving the production of MD2 pineapple in locality of Dabou

THE ESTIMATION OF THE HERBACEOUS BIOMASS IN THE SAHELIANS PASTORAL ZONES USING A GIS

peer reviewedIn the Sahel region the pastorals resources are strongly linked to the fluctuation of the biomass production and as well as the breeding systems, which are based on the transhumance and the nomadism as well. In the present study, an integrated approach of multi-source, multi-type and multi-scales data analysis in the pastoral zone in Senegal, Mali, Burkina Faso, Mauritania, Niger and Chad has been developed using PC-Arc/Info and Arc/View potentialities for the purpose of Sahelian rangeland production estimation.AP3

Municipal household waste used as complement material for composting chicken manure and crop residues

There are few organic materials available as agricultural soil amendment because their low chemical content means that large quantities are required. In order to improve the availability of raw materials for composting, as well as the quality of the compost produced, municipal solid waste (MW) was added to cotton-seed residue (CSR) and to the association of CSR with chicken manure (M) in different weight/weight (MW/added materials) ratios of 5:1 and 2:1. Aerobic composting was processed and compost yield was determined, as well as compost particle size and pH. Also, the compost bulk density and its water holding capacity were determined as well as contents of total nitrogen, carbon, phosphorus, calcium (Ca), magnesium and heavy metals. According to its pH and carbon/nitrogen ratio values, the municipal waste of Cotonou was judged to be a good raw material for composting in order to improve availability of the organic source of nutrients. The composts produced with MW+M+CSR had the highest potential for amending Ferralsols, especially with a mixture of 2:1 (200 kg MW+100 kg M+100 kg CSR) that could be applied at 10 t ha–1. However, further improvement in composting methods was suggested to increase Ca++ and reduce mercury contents, respectively. Moreover, potassium balance should be improved in the produced compost

Enquête sur l’utilisation et l’effet des médicaments à base de plantes chez les patients hépatiques hospitalisés au Service de médecine et d’hépatogastroentérologie du Centre Hospitalier Universitaire (CHU) de Cocody en Côte d’Ivoire

Objectif: Cette étude a été menée afin d’identifier les plantes et leurs produits dérivés utilisés par les patients avant leur admission au service de Médecine et d’Hépato-gastroentérologie du Centre Hospitalier et Universitaire (CHU) de Cocody en Côte d’Ivoire.Méthodologie et résultats: Un questionnaire a été administré à ces patients au cours d’entretien semistructuré lors des enquêtes menées entre février et mai 2016. Un total de 125 patients a été enquêté dont 88 % ont eu recours à la médecine traditionnelle les 12 derniers mois précédent l’enquête. Les plantes médicinales sont le plus souvent consommées par les patients pour traiter des maladies telles que le paludisme et l’asthénie avec des fréquences de citation (fc) de 45,5 % et 11 % respectivement. Vingt (20) plantes médicinales appartenant à 13 familles et 19 genres ont été citées. Vernonia amygdalina (Asteraceae) « feuille amère", avec une fc de 16,32 %, Alchornea cordifolia (Euphorbiaceae) "Arbre de djeman" et Senna occidentalis (Fabaceae) "faux kinkéliba" (fc = 12,24 %), étaient les espèces les plus utilisées.Conclusions et application des résultats: Les patients hépatiques ont eu recours aux produits de la médecine traditionnelle. Ces résultats sont importants pour la sécurité sanitaire des consommateurs de plantes médicinales. Ils pourront contribuer à améliorer le diagnostic des maladies du foie.Mots-clés: Centre hospitalier, Côte d’Ivoire, Hépatotoxicité, Maladies du foie, Plantes médicinales, PatientsEnglish Title: Survey on the use and effect of herbal medicines on hospitalized liver patients in the Department of Medicine and Hepatogastroenterology at the University Hospital Center (UHC) of Cocody in Côte d’IvoireEnglish AbstractObjective: This descriptive study was conducted to identify the plants and their derivatives used by patients prior to their admission to the Medicine and Hepato-gastroenterology department of the University Hospital Center (UHC) of Cocody in Côte d'Ivoire.Methods and Results: A semi-structured interview questionnaire was applied to these patients from February to May 2016. A total of 125 patients were interrogated, 88% of whom used traditional medicine in the last 12 months prior to the survey. The medicinal plants were mostly consumed by patients to treat diseases such as malaria and asthenia with citation frequencies (cf) of 45.5% and 11%, respectively. Twenty (20) plants species belonging to 13 families and 19 genders were cited. Vernonia amygdalina (Asteraceae) "bitter leaves" with cf of 16.32%, Alchornea cordifolia (Euphorbiaceae) "christmas bush" and Senna occidentalis (Fabaceae) "negro coffee" (cf = 12.24%) were the most used species.Conclusion and application of results: The liver patients have used products of traditional medicine. The results are important for the safety of consumers of medicinal plants. These results may contribute to improving the diagnosis of liver diseases.Keywords: Hospital center, Côte d’Ivoire, Hepatotoxicity, Liver diseases, Medicinal plants, Patient

Metallic Trace Elements (MTE) in soils and plant organs of some crop in periurban of Abidjan (Ivory Coast)

The quality of the plant production in periurban agriculture is subjected to question given the potential contamination of soils that can affect the crops. The levels of contamination of soils and vegetables by Metallic trace elements (MTE) as copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb) in the district of Abidjan, have been evaluated. Multi-sites survey of cropping areas of sweet potato and Hibiscus was conducted in three municipalities in Abidjan (Port-Bouët, Yopougon and Bingerville) in relation to the intensity of industrial and commercial activities. The site of Bingerville has been used as the reference site referring to the low activities. Soil samples (in 0-20 cm and 20 - 40 cm), combined with that of plants (leaf, stem, and root), and water were collected, transported in laboratory for analysis. The total amounts of MTE in soil, as well as the different fractions extracted were determined in addition to the respective concentration in plants (Hibiscus and Sweet potato). Toxic level of Pb (< 8 mgkg-1) was observed in the plant organs collected at Port-Bouët site indifferently to crops while lowest content of Pb (35.5 mgkg-1) was accounting for the soil of Yopougon (39.8 mgkg-1). A neutral pH of the soil has been considered more favorable to the contamination of plants in Pb on the polluted sites somewhat differing for extractable fractions. The acidity and small width of leaf as observed for Hibiscus, were identified as the control factors of crop contamination in periurban agroecosystems prone to Pb pollution. To strengthen the consistency of the knowledge, studies of the interaction between Pb and Zn as well as the translocation of Pb in the plants to tubers are suggested in the tropical ecosystems

BIOLOGY AND HARMFULNESS OF INVASIVE DISCOSCOREA IN SUGARCANE (SACHARUM OFFICINARUM L.) CULVITATION IN THE AREA OF THE SUGAR REFINERY COMPLEX OF FERKESEDOUGOU IN NORTH COTE D’IVOIRE

*Author for Correspondence Floristic sampling done in hundred plots around the sugar refinery complex of Ferke 1 and Ferke 2 located in Ferkessedougou in North Cote d’Ivoire during the cropping cycle of 2011-2012, revealed 30 species of weed including 6 of invasive Discoreas as D. bulbifera, D. dumetorum, D. hirtiflora, D. lecardi,. paraehensillis and D. preussii. Observations done on the biology, the phenology and the harmfulness showed that the occurrence of invasive Dioscorea in sugarcane fields was effective by bulbils and in certain level by tubers and bulbils generating new tubers, when produced during the vegetative growth stage between the second and seventh months of cultivation. D. bulbifera, D. dumetorum, D. hirtiflora and D. lecardi were producer of bulbils and occurred in highest potential densities. Excepted for D. lecardi, they were more harmful to sugarcane plant because of overlapping of vegetative cycle durations likewise for D. praehensilis. Hence, these weeds may have high competiveness ability with the crop for soil water and nutrient uptake as well as for sun light reception. Key Words: Weed, Dioscorea, Sugarcane, Biology, Phenology and Harmfulnes