Agronomic potential value of household urban solid wastes by composting and composts quality assessment

Using composting technology, the biodegradable fraction of solid wastes collected from Agbalepedogan district in Lomé (Togo) was transformed into composts with no phytotoxicity suitable for use in agriculture. The household urban solid wastes were mixed with poultry manure and Mucuna pruriens leaves in appropriate percentages and transformed into composts. The composting process was monitored by temperature, pH and C/N ratio controlling. The composts quality was appreciated by phytotoxicity test, particle size distribution, contents of nitrogen, phosphorus, potassium, organic matter and trace elements. The results showed that composts particle size distribution presented four fractions (>10 mm, 5-10 mm, 2-5 mm and ≤2 mm) whose average percentages are respectively 9.04±0.2%; 10.71±0.2%; 12.68±0.4% and 67.53±0.6%, respectively. Composts produced contained 1.02±0.1% - 2.72±0.2% of nitrogen, 1.35±0.3% - 2.70±0.4% of phosphorus, 1.31±0.2% - 1.72±0.3% of potassium and 23.50±0.4% - 37.75±0.5% of organic matter. The pH in final composts were between 8.50±0.2 and 9.00±0.3 while C/N ratio varying from 8.06±0.2 to 13.13±0.2. The concentrations of some heavy metals in final products were 79.8±1.7 - 140.2±1.6 mg/kg.dm of zinc, 27.1±1.01 - 76.6±1.03 mg/kg.dm of copper, 2.07±0.33 - 9.19±0.22 mg/kg.dm of lead, 4.13±0.16 - 11.05±0.36 mg/kg.dm of nickel and 0.79±0.02 - 2.15±0.03 mg/kg.dm of cadmium. These concentrations were lower than the limited value for heavy metals prescribed by French and US EPA regulation for organic and organic-mineral fertilizers. Int. J. Agril. Res. Innov. Tech. 9(2): 1-8, December 201

Caractérisation physico-chimique des sols en vue de l’amélioration de la productivité du manioc (Manihot esculenta Crantz) dans la région de Damara au centre-sud de Centrafrique

La présente étude vise à améliorer la productivité du manioc (Manihot esculenta), aliment de base des centrafricains. Plus spécifiquement, il s’agit de (i) caractériser les propriétés physico-chimiques du sol et (ii) déterminer les indicateurs de fertilité des sols étudiés. La collecte des données a consisté à prélever le sol de la couche 0-20 cm, sur les champs de manioc du site expérimental de LaSBAD. Les sols ont été prélevés suivant un dispositif de randomisation, en vue de constituer un échantillon composite de 1 kg par champs. Ils sont séchés, tamisés et analysés au laboratoire de sol du CIRAD-Montpellier-France. Les résultats analytiques de sol ont été comparés à des valeurs de références. Les sols étudiés présentent une texture loameuse et un pH optimal de 5,5, favorable à la culture du manioc, et sont très pourvus en matière organique. Le bilan des éléments nutritifs révèle des carences en calcium et en échangeable. L’analyse en composantes principales a montré une corrélation entre les indicateurs de la fertilité des sols. L’utilisation des légumineuses et la fertilisation organo-minérale à une dose adéquate sont des solutions envisageables pour améliorer la productivité du manioc en Centrafrique.Mots clés: indicateur de fertilité, productivité, manioc, propriété physico-chimique, CentrafriqueEnglish Title: Characterization physicochemical soils to improve productivity of cassava (Manihot esculenta Crantz) in the region of Damara in south-central of Central African RepublicEnglish AbstractThe present study is a contribution to the improvement of cassava (Manihot esculenta) tubers’ productivity in the Republic of Central Africa. Especially it aims to characterize the physicochemical properties of soil and (ii) assess fertility indicators of soil. Data collection was consisted to sample the soil from horizon 0-20 cm in cassava fields of producers and the agricultural site of the LaSBAD. Soils were sampled randomly to form a composite sample of 1 kg per field. Soil samples were dried, sieved, and analysed within the laboratory of soil of CIRAD in Montpellier-France. The analytical results of soils were compared to reference values. The studied soils are in their surface organic loamy texture and optimal of 5.5 pH suitable for the cultivation of cassava. They are well supplied with organic matter. The nutrient balance showed that the most significant deficiencies include calcium and magnesium exchangeable. The principal component analysis showed a best correlation relationship between indicators of soil fertility. The use of legumes, and fertilization organicmineral at one dose adequate were possible conceivable solutions to improve cassava in Central African Republic.Keywords: Diagnosis of deficiency, soils’ fertility, cassava, savannah, Central African Republi

Gestion des pesticides sur les perimetres maraichers de la Zone Cotiere du Togo

Objectif : Evaluer les pratiques d’utilisation des produits phytosanitaires sur les périmètres maraîchers de la zone côtière du Togo. Méthodologie : Une enquête a été réalisée auprès de 63 maraîchers. Le questionnaire a porté sur les pesticides utilisés, la dose appliquée, la fréquence d’application, la protection des maraîchers pendant l’usage des pesticides, la durée avant récolte, la gestion d’emballages des pesticides, mode d’acquisition des parcelles cultivées et les caractéristiques socio-professionnelles des maraîchers. Les résultats : Il a été observé que le maraîchage est généralement pratiqué par les hommes (78%) dont 81% ont l’âge compris entre 30 et 60 ans tous ayant un niveau d’études primaire et secondaire (96%). Les principales cultures sont la carotte, la betterave et la laitue (55,56%). Les pesticides utilisés pour prévenir les nuisibles et réduire la pénibilité du travail sont les insecticides, les fongicides et les herbicides. La majorité des maraîchers (92,0%) ne dispose pas d’Equipements de Protection Individuelle (EPI) et au-delà de la moitié (60,3%) n’a pas une formation en utilisation des pesticides. Conclusion : Les maraîchers de la zone côtière du Togo n’ont pas une bonne connaissance de l’utilisation des pesticides. Ceci peut les exposer au risque d’intoxication et aux maladies liées à la mauvaise utilisation des produits phytosanitaires et peut accroître le risque de résistance des ravageurs et des pathogènes.   English title: Management of pesticides on the market gardening’s perimeter of Coast Zone of Togo Objective: Evaluate the practices of market gardeners on the use of the phytosanitary product on the market gardening perimeter of coastal zone of Togo. Methodology: A survey was carried out among 63 market gardeners. The questionnaire focused on the pesticides used, the dose applied the frequency of application, the protection of market gardeners during the use of pesticides, the time before harvest, the management of pesticide packaging, the legal status of the plots cultivated, and the socioprofessional characteristics of market gardeners. The results: It has been observed the market gardening is generally practiced by men (78%), 81% of whom are between 30 and 60 years old, all having a primary and secondary education (96%). The main crops the carrot, beetroot and lettuce (55.56%). The pesticides used to prevent pests and reduce the drudgery of the work are insecticides, herbicides and fungicides. The majority of market gardeners (92.0%) do not have Personal Protective Equipment (PPE) and 60.3% do not have training in the use of pesticides. Conclusion: Market gardeners in the coastal zone of Togo do not have a good knowledge of the use of pesticides. This can expose them to the risk of poisoning and diseases in the relationship with bad use of the phytosanitary product and can increase the risk of resistance of pests and pathogens to pesticides

Effets de doses moderees d’azote sur les performances des plantules de cacaoyers (Theobroma cacao Linn.) dans la zone forestiere du Togo

La couverture des besoins en nutriments des cacaoyers, surtout en azote (N), reste indispensable pour une meilleure croissance des plantules. L’objectif de cette étude était de déterminer les effets de doses modérées d’azote sur les performances agronomiques des plantules de cacaoyers en pépinière dans la zone forestière du Togo. Des essais ont été conduits dans un dispositif en block aléatoire complet avec quatre répétitions afin d’identifier la dose complémentaire optimale d’azote qui permette une meilleure croissance et nutrition des plantules de cacaoyers. Les doses testées étaient 0 ; 0,5 ; 1 et 1,5 g.plant-1 d’urée (46%N). Les résultats ont montré que les doses de 0,5 et 1 g.plant-1 sont les plus aptes à fournir les meilleures performances agronomiques des plantules de cacaoyers en pépinière dans la zone forestière du Togo. Cependant, la dose de 1 mg.plant-1 est optimale pour une bonne croissance et une nutrition équilibrée des plantules de cacaoyers et serait donc à recommander pour la conduite des pépinières de cacaoyers dans la zone.Mots clés: Theobroma cacao, pépinière, azote, TogoEnglish Title: Effects of moderate amounts of nitrogen on the performance of cocoa seedlings (Theobraoma cacao Linn.)  in the forest zone in TogoEnglish AbstractThe cover of the nutriments requirements for cacao-trees, especially in nitrogen (N), remains essential for a better growth of the seedlings. The objective of this study was to determine the effects of moderate amounts of nitrogen on the agronomic performances of the cocoa seedlings in nursery in the forest belt of Togo. Tests were carried out in a complete randomized block design with four repetitions in order to identify the optimal complementary amount of nitrogen which allows a better growth and nutrition of the cocoa seedlings. The amounts tested were 0; 0.5; 1 and 1.5 g.plant-1 of urea (46%N). The results showed that the amounts of 0.5 and 1 g.plant-1 are ready to provide the best agronomic performances of the cocoa seedlings in nursery in the forest zone of Togo. However, the dose of 1 mg.plant-1 is optimal for a good growth and a balanced nutrition of the cocoa seedlings and would be thus to recommend for the cocoa seedbeds production in the zone.Keywords: Theobroma cacao, nursery, nitrogen, Tog

Effects of charcoal production on soil biodiversity and soil physical and chemical properties in Togo, West Africa

In Togo, traditional energy sources including charcoal represent 80% out of total household energy requirements. The techniques of charcoal production in earth kiln are quite common. During carbonization, the temperature rises from 20 to over 500°C. This study focuses on the impact of this high temperature on the soil properties and soil fauna in three biogeographical zones of Togo. The methodology used consists in comparison of soil sampling in surface layer (0-20 cm depth) inside burnt plot i.e. inside the kiln to an unburnt plot in charcoal production area. The results revealed that the soil physical, chemical and microbial properties were altered. The organic matter was destroyed; it is higher at the unburnt plot level than inside the kiln. The soil pH increased at the kiln level by the provision of rich ash bases during the carbonization. Fire increased the permeability at the kiln level by raising the bulk density and the total porosity of soil. The variation in microbial biomass induced by the heat around the kilns is different according to the ecosystem; it is of 15 m radius around the kilns in Sudanian or Guinean savanna areas while this radius is 5 m in Semi-deciduous forest. The soil fauna assessment permitted to record 81 micro-organisms belonging essentially to the Beetles, Hymenoptera, Heteroptera, Diptera, Orthoptera, Myriapods, Homoptera, Acarians, Nematodes, Isoptera, etc. The hypogeal biodiversity index calculation (average species richness, Shannon average indexes and average evenness) revealed that farther moving away from the kiln, greater the fauna species diversity was.© 2009 International Formulae Group. All rights reserved.Key words: Charcoal production, kiln, soil physical and chemical properties, soil biodiversity, Togo

Assessment of average exposure to organochiorine pesticides in Southern Togo from water, maize (Zea mays) and cowpea (Vigna unguiculata).

International audienc

Response of maize (Zea mays L.) ikenne variety to application of household urban solid wastes compost

Soils fertility declining limits agricultural production in Togo where maize (Zea mays L.) is most cereal cropping and base staple food. Currently, mineral fertilizers are beyond the reach of farmers due to high price and limited availability. This study assessed the response of household urban wastes compost to the growth and yield of maize Ikenne variety. Experiments were performed in rainy season of years 2018 and 2019 at Teaching Research and Demonstration Farm of Agronomy School in University of Lome, Togo. Agronomic trials were set at randomized in complete block design with three replications, where control plots, compost plots at different doses and mineral fertilizers plots constituted the treatments. The growth parameters, including plant height, stem girth, leaf area and number of leaves per plant, were measured at the milky maize stage. The yield parameters, including length and girth of cob, thousand grains weight, grain yield and straw yield, were collected at harvesting. Data were statistically analyzed. The results showed three distinct homogeneous groups of treatments both for growth and yield parameters. Plots treated with compost at 30 t ha-1 and 40 t ha-1 constitute the best group, which differs significantly from the second group formed by plots treated with compost at 10 t ha-1 and 20 t ha-1 and mineral fertilizer plots. Control treatments constitute the last group. Growth and yield parameters values increase with compost dose. Far from being used alone in place of mineral conventional fertilizer, integrated fertilization based on combination of mineral fertilizer and compost of household urban wastes will investigated in maize cropping in southern Togo for optimal compost dose to recommend

Stabilite structurale de sol ferrallitique "terre de barre" amende aux composts de dechets menagers solides urbains

Le sol ferralitique du Sud Togo communément appelé "terre de barre" connait, sous l’effet de la pression démographique, une dégradation et une baisse de la fertilité caractérisées par une diminution du stock de carbone organique et une déstructuration des horizons de surface mettant à rudes épreuves la production agricole. Une possibilité de les restaurer passe par l'utilisation de la fumure organique. Le présent travail évalue la stabilité structurale de la terre de barre à la Station d’Expérimentations Agronomiques de l’Université de Lomé après 4 saisons de culture (tomate en alternance avec le maïs). Le dispositif expérimental utilisé était celui en blocs aléatoires complets avec neuf traitements à trois répétitions. Deux types de composts élaborés à base d’ordures ménagères et de fientes de volailles ont été appliqués aux doses de 10 t.ha-1, 20 t.ha-1, 30 t.ha-1 et 40 t.ha-1. Les échantillons de sol prélevés à la tarière manuelle dans la couche superficielle 0-15 cm sur les parcelles expérimentales ont été soumis à trois différents prétraitements dont l'humectation rapide, la désagrégation mécanique et l'humectation lente pour l’évaluation de la stabilité structurale. Les résultats montrent : (i) une corrélation positive entre la stabilité structurale et le taux de matière organique dans le sol qui est fonction de la dose de compost appliquée, (ii) une réduction de la densité apparente et (iii) une augmentation de la porosité totale du sol. L’agrégation et l’augmentation de la porosité induites par l’apport de compost limiteraient davantage la déstructuration des horizons de surface de la terre de barre. Mots clés: terre de barre, stabilité structurale, composts, taux de matière organique, porosité totale et densité apparente English Title: Structural stability of ferralitic soil "terre de barre" amended by composts of solid urban household wastes English Abstract The ferralitic soil in southern Togo, commonly called "terre de barre" is experiencing under the effect of demographic pressure, a degradation and a decline in fertility characterized by a decrease in the organic carbon stock and a destructuring of the surface horizons with decreasing agricultural production. One possibility of restoring them is through the use of organic manure. This work assesses the structural stability of the “Terre de barre” at the Agronomic Experimentation Station of the University of Lomé after 4 growing seasons (tomato alternating with corn). The experimental device used was that in complete random blocks with three repetitions. Two types of compost made from household refuse and poultry droppings were applied at the doses of 10 t ha-1, 20 t. ha-1, 30 t ha-1 and 40 t ha-1. The soil samples taken with the manual auger in the 0-15 cm surface layer on the experimental plots were subjected to three different pretreatments including fast wetting, mechanical disintegration and slow wetting for the assessment of structural stability. The results show: (i) a positive correlation between structural stability (aggregation) and organic matter content in soil, which is a function of the applied compost dose, (ii) a reduction in bulk density and (iii) an increase in the total porosity of the soil. The aggregation and the increase in porosity induced by the addition of compost would further limit the destructuring of the surface horizons of the “terre de barre”. Keywords: "Terre de barre", structural stability, composts, organic matter rate, total porosity and bulk densit

Residus de pesticides organochlores retrouves dans quelques poissons du Lac Togo et evaluation du potentiel de risque pour le consommateur

Les pesticides organochlorés, précédemment utilisés en agriculture et dans des programmes de lutte contre les vecteurs de maladies en santé publique, ont été recherchés dans 83 poissons du lac Togo appartenant à 9 espèces en vue d’évaluer le potentiel de risque pour le consommateur. Les méthodes analytiques d’extraction de résidus de pesticides aux solvants organiques et de chromatographie en phase gazeuse révèle la contamination de ces poissons par pp′-DDT, pp′-DDE, lindane, α-HCH, aldrine, dieldrine, heptachlore époxyde, α endosulfan et β-endosulfan à des concentrations allant de 0,11±0,09 à 2,80±0,22 μg.kg-1 de poids frais. Les valeurs résiduelles de pesticides retrouvées dans les poissons excédaient les limites maximales de résidus fixées par l’Organisation Mondiale de la Santé/Organisation des Nations Unies pour l'Alimentation et l'Agriculture (OMS/FAO). Cependant, une comparaison de l’ingestion journalière estimée de chaque pesticide par la consommation de poissons étudiés aux doses journalières admissibles établies par l’OMS/FAO indique que les poissons du lac Togo ne représentent pas de danger pour le consommateur moyen.Mots clés: Lac Togo, poisson, contamination, résidus de pesticides organochlorés, risqueEnglish Title: Organochlorine pesticide residues found in some fishes from Lake Togo and assessment of the potential risk to the consumerEnglish AbstractOrganochlorinated pesticides historically used in agriculture and in health program against sickness vectors in health public were investigated in 83 fishes including 9 fish species collected from Lake Togo in order to assess the risk of pesticide intake by the local population through the fish consumption. The analytical methods included solvent extraction of pesticide residues and their subsequent quantification using gas chromatograph revealed the contamination of these fishes by pp′-DDT, pp′-DDE, lindane, α-HCH, aldrin, dieldrin, epoxyde heptachlor, α-endosulfan and β-endosulfan in concentrations ranged from 0.11±0.09 to 2.80±0.22 μg.kg-1 of fresh product. The residual pesticide concentrations found in fishes exceeded the maximum residue set by limit of World Health Organization/Food and Agriculture Organization of the United Nations (WHO/FAO). Although, a summed risk assessment, comparing pesticide intake levels through fish consumption with tolerable daily intake levels proposed by the WHO/FAO, showed in all cases a low risk for fish customer.Keywords: Lake Togo, fish, contamination, organochlorine pesticide residues, ris