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Context: In Côte d’Ivoire, industrial banana plantations are faced with the problem of weediness. However, the use of herbicides as a means of control presents significant risks for human health and the environment. The abandonment of these products for more ecological alternatives such as cover crops is imminent. Aims: This study aimed to compare the relative abundance and the density of the main plant-parasitic nematodes in the roots of banana and cover crops according to three weed management treatments. Study Design and Methodology: The experimental design was a three-repeat Fisher block of three treatments consisting of implementation of A. repens and D. adscendens as cover crops and spraying of two synthetic herbicides (glufosinate and glyphosate) for weed management. The relative abundance and density of nematodes in the roots of banana and cover crops were assessed quarterly after extraction by the rapid double centrifugation-flotation method and enumeration under an optical microscope. Results: Both cover crops and banana plants had their roots infested by the major parasitic nematodes evaluated (Radopholus similis, Pratylenchus spp., Helicotylenchus spp., Meloidogyne spp., Rotylenchulus reniformis and Hoplolaimus pararobustus). These infestations were not a function of weed management treatments. Compared to the use of herbicides, A. repens and D. adscendens used as ground cover did not significantly increase or decrease nematode dynamics in the plots. Individuals extracted from the roots of the cover crops, and particularly from D. adscendens, were more numerous than from the roots of the banana plants. In terms of proportions, Pratylenchus spp., R. similis, Helicotylenchus spp. and Meloidogyne spp. were most abundant. R. reniformis and H. pararobustus as well as various nematodes (plant parasites: Hirschmanniella spp., Xiphinema spp., ..., and non-plant parasites: fungivorous, carnivorous, bacterivorous, ...) were in the minority. Conclusion: The results, particularly those of A. repens, could be useful in the biological, ecological and sustainable management of weed in banana plantations without important risks of pest pressure.

From years ago, climate change effects are happening in different areas of the world, including Rwanda. Potato as one of main commodities grown mainly in the cooler and wetter highlands of Rwanda, its production could be facing the global warming. The purpose of this study is to carry out weather (temperature and rainfall) change dynamics in the potato growing zones of Rwanda over the last thirty years. Weather daily data from 1987 to 2016 were collected from three weather stations, at Kawangire for low elevation, at Gikongoro mid elevation, and at Kora high elevation, respectively. Farmers were interviewed to know their perceptions on weather conditions during past thirty years. Weather data were analyzed by ombrothermic diagram, Nickolson Index and graphing with generated trend equation methods. Interview data were analyzed with Chi-square test at P =.05. Results have shown as dry June, July and August months in low elevation; June, July and August in medium elevation and June and July in high elevation depending on decade. Rainfall was increasing in low and medium elevations, while it was decreasing in high elevation. Temperature was decreasing in low elevation area and it was increasing in medium and high elevation areas. All interviewed farmers confirmed long term-shift in temperature and precipitations. A total of 95%, 54% and 43% of farmers from respectively low, medium and high elevations reported that weather was becoming wetter during last years. As conclusion, potato growing cooler and wetter conditions of high elevation are shifting to low elevation in Rwanda. For climate change mitigation, Rwanda needs to promote potato in its Eastern part, the low elevation region, in order to increase the crop production in the future.

From years ago, many climate change effects are happening in world different areas, including in Rwanda. The purpose of this study is to determine rainfall and temperature evolution trend for thirty years, in Rwandan zones growing potato. Temperature and rainfall daily data were collected from three weather stations which are Kawangire, Gikongoro and Kora recognized as respectively low, medium and high elevations. Farmers were interviewed to know their perceptions on weather conditions during past thirty years. Temperature and rainfall data were analyzed by ombrothermic diagram, Nickolson Index and graphing with generated trend equation methods. Interview data were analyzed with Chi-square test at P-Value significance

Les auteurs rapportent deux cas de tuberculose de la prostate chez des patients immunocompétents. Ces deux cas ont été recensés sur une période de 8 ans. Le premier patient, âgé de 78 ans avait une symptomatologie clinique simulant une hypertrophie bénigne de la prostate. Le deuxième patient âgé de 28 ans nous a été référé pour suspicion de cancer de la prostate avec des métastases vertébrales. Dans les deux cas le diagnostic de tuberculose de la prostate était histologique, reposant sur l´analyse de copeaux de résection de la prostate ou de caro´es biopsiques. L´évolution clinique était favorable sous anti bacillaires chez nos deux patients.

With the depletion of forest reserves, coffee growing based on extensive and shifting cultivation mode is no more reproductive. Thus, soils of different coffee growing areas were studied in order to diagnose the fertility level, their potential for productivity of new varieties of coffee (Coffea canephora Pierre, var. Robusta) and their sustainable managements. In total, 156 soil samples were collected and analyzed in the laboratory using standard methods to determine their physicochemical statutes. The results obtained show a low nitrogen content of less than 0.27% in all soil mapping units, a base saturation percentage lower than 60% for the vast majority of soils and crucial presence of organic matter on distribution of physicochemical properties. Clustering of results identified two main components, which accounted for 88.69% of the variability of the data and the grouping into three communities by similarity of features. In view of these results, a sustainable production of the coffee trees requires a fertilization program for the improvement of soils under coffee trees.

The pénal prison did not exist in the diverse répressive Systems of precolonial Guinea. For decentralized as well as centralized societies, the penal order was based on retaliation and compensation. In addition, sentences depended on the social status of the condemned. Tribunals were composed of judicial specialists who also engagea in political and religious functions. The slave trade profoundly affected this System, and encouragea tribunals to produce more captives for the new market. The colonial conquest, however, through the use of penal confinement, introduced an even more radical rupture with the old order. Guineans interpreted such confinement as infamous and degrading. They invented a number of spiritual and material devices in order to avoid the prison altogether, or to purify themselves from the stain of incarceration., Les divers systèmes répressifs qui prévalaient en Guinée précoloniale ne connaissaient pas l'emprisonnement. Dans les sociétés centralisées comme dans les sociétés décentralisées, le principe pénal était fondé sur la vengeance et la réparation. L'application des peines, en outre, dépendait du statut social des individus condamnés. Enfin, les tribunaux étaient formés de spécialistes exerçant à la fois des fonctions judiciaires, politiques et religieuses. La traite esclavagiste affecta grandement ces systèmes, incitant les tribunaux à produire des captifs pour le nouveau marché. Mais c'est la conquête coloniale qui introduisit une rupture définitive avec l'ordre ancien, notamment à cause de l'emprisonnement. Les Guinéens interprétèrent cette peine nouvelle comme infamante et dégradante, et déployèrent une imagination fertile soit pour y échapper, soit pour se purifier de la souillure que l'incarcération entraînait., Dan Diallo Chérif Mamadou. Les anciens systèmes répressifs guinéens face à l'introduction de la prison coloniale. In: Revue française d'histoire d'outre-mer, tome 86, n°324-325, 2e semestre 1999. Pour une histoire du contrôle social dans les mondes coloniaux : justice, prisons, et enfermement de l'espace, sous la direction de Florence Bernault, Pierre Boilley et Ibrahima Thioub. pp. 17-28.

En zone tropicale, la riziculture (oryza sativa L) de bas-fond avec ou sans maîtrise de l'eau, est souvent confrontée au problème de toxicité ferreuse. Cette contrainte édaphique est couramment observée dans les bas-fonds ouest-africains. C'est un trouble nutritionnel associé à de fortes concentrations de fer dans la solution du sol. Les conditions réductrices que l'on rencontre couramment dans les sols de bas-fond engorgés d'eau sont précurseurs de la toxicité ferreuse par la solubilisation dans la solution du sol de la quasi-totalité du fer sous forme ferreux (Fe2+). Ce fer ferreux (Fe2+) absorbé en abondance par la plante se concentre dans les feuilles, entraînant une décoloration des limbes, une réduction du tallage, de la taille des plants, et provoque une baisse importante des rendements. Une étude a été réalisée afin de déterminer l'effet de la toxicité ferreuse sur le rendement et les composantes du rendement du riz. Quatre variétés de riz (BKE189, CG14, CK4 et TOX3069), à sensibilité différente à la toxicité ferreuse, ont été cultivées en champ à Bouaké (site non toxique) et à Korhogo (site affecté par la toxicité ferreuse). Les résultats de l'étude montrent que la toxicité ferreuse entraînerait chez les variétés sensibles une perturbation de la distribution des synthétisants produits dans les feuilles, ce qui aurait pour conséquence un mauvais remplissage des grains lors de la formation de ceux-ci, d'où des grains plus légers à la récolte.

Rice production is usually reduced by water stress that can evenly occur during rice cycle in West Africa under bimodal rainfall pattern. In order to determine the effects of water stress on rice grain quality, experiments were conducted on upland site (on ferralsol) at the main AfricaRice research center at M'be, 30 km North of Bouaké, Côte d'Ivoire. The rice varieties CG14 (Oryza glaberrima), WAB56-104 (Oryza sativa), and NERICA1 (cross WAB56-104 x CG14) were sown at 25 × 25 cm spacing during the dry season cropping period of 2000, 2001 and 2002. Irrigation line (Boon irrigation) was used to supply water until flowering stage. Water was then supply manually from the milky stage of each variety to its full ripening stage. Physical (husking yield, milling recovery, and head rice ratio), chemical (amylose and proteins contents) and cooking parameters (cooking time, volume expansion, rice flour gelatinization temperature, consistency and viscosity) of the harvested grains were determined in the laboratory. The results showed a significant difference (p < 0.05) between all the parameters in comparison with the checks samples and stressed crop. In general, NERICA 1 showed better physical and cooking quality traits than its parents. Rice samples from plots subject to lower water availability during repining stage showed higher protein content for all varieties studied. Increase in the average protein content of stressed samples were 31, 11.8 and 13.3% times, respectively for NERICA 1, CG14 and WAB56 -104, where (using the protein content of check plots as 100%) NERICA 1 showed higher husking yield, total mean milling recovery and head rice ratio for samples collected on stressed plots than the glaberrima and the sativa samples recorded on similar plots. Finding showed that cooking properties that meet West African rice consumers' preferences for cooked rice were more improved for NERICA 1 than its parents in comparison with samples collected from stressed plots. It is concluded that moisture stress at ripening stage should be further investigated as potential indirect means of improving rice grain quality.

La culture du riz en condition de bas-fond, en zone tropicale, est fréquemment confrontée au problème de la toxicité ferreuse. Cette contrainte de type édaphique est très souvent observée dans les bas-fonds ouest africains C'est un désordre nutritionnel associé à de fortes concentration de fer sous sa forme ferreuse dans la solution du sol. Ce fer ferreux absorbé en abondance par le plant de riz, se concentre dans les feuilles, entraînant alors une décoloration des limbes, une réduction du tallage, de la taille des plants, et provoque une baisse importante des rendements. Cette contrainte a fait l'objet d'une étude sous forme d'enquête dans trois pays de la sous région ouest africaine (Guinée, Côte d'Ivoire et Ghana). L'objectif était de quantifier l'impact de la contrainte sur la production rizicole dans les zones étudiées. Cette enquête a porté sur plus de 4600 parcelles repartis entre 757 bas-fonds. Plus de 50% des bas-fonds et environ 60% des parcelles cultivées en riz sont intoxiqués Par ailleurs, 10% de ces bas-fonds ont été abandonnés en raison d'une pression de toxicité ferreuse trop importante. Les résultats montrent également que plus de 55% des surfaces rizicoles sont affectées par la contrainte. L'impact sur le rendement est aussi significatif puisque les parcelles infectées peuvent perdre en moyenne jusqu'à 54% de leur potentiel de production par rapport aux parcelles saines.

Rice cropping in lowland conditions in tropical zones frequently encounters the problem of iron toxicity. This edaphic type of constraint is very often observed in West African lowlands and is a nutritional disorder associated with high concentration of iron in its ferrous form in soil solution. This ferrous iron is absorbed in abundance by the rice plant, accumulates in the leaves, creates discoloration of the lamina, reduces tillering and plant height and causes significant yield loss. This constraint was studied in the form of an investigation conducted in three West African countries (Guinea, Côte d'Ivoire and Ghana) with the goal of quantifying the impact of the constraint on rice production in the zones surveyed. The investigation was conducted on over 4600 plots in 757 lowland areas. Over 50% of the lowlands and about 60% of the plots cropped with rice were toxic, and 10% of these lowlands had been abandoned because of excessive iron toxicity pressure. The results also showed that over 55% of the rice area was affected by the constraint. The impact on yield is also significant since the affected plots can lose up to 54% on average of their production potential compared to toxicity-free plots.