RESUMEL'étude a été réalisée dans le but de caractériser la fertilité des sols sous cacaoyers dans le Sud-Ouest de la Côte d'Ivoire. Des échantillons, representatifs des sols de Méagui et de San-Pedro, ont été prelevés sous les cacaoyères dégradées et non dégradées et sous forêt naturelle. Les échantillons ont été analysés au laboratoire des sols selon des méthodes standard. Des analyses statistiques multidimensionnelles (ACP et ARH) ont été effectuées en vue d'évaluer les paramètres de fertilité des sols. Les résultats montrent que les sols des cacaoyères non dégradées et ceux de forêt (groupe 1) ayant presenté des teneurs en matières organiques supérieures à 3 % ont été plus favorables au developpement du cacaoyer. Ce qui n'as pas été le cas pour les sols sous cacaoyères dégradées. Ceux-ci (groupes 1, 2 et 3, ont été caractérisés par des teneurs en matières organiques plus faibles (<3%). Dans tous les sols (cacaoyères dégradées, cacaoyères non dégradées et forêt ), les principales caractéristiques du complexe absorbant montrent des contraintes pour le cacaoyer. Tous les sols ont été déficients en K (<0,2 cmol (+) kg -1 ) ; la proportion de K, par rapport à la somme des bases échangeables (K + Ca + Mg) ou SBE a été < 4 %. Le ratio SBE 6,15/N < 8,9 indiquant un déséquilibre entre les bases échangeables et N ; la correction de ce déséquilibre nécessite une augmentation des niveaux des bases échangeables. Les sols ont été déficients en P assimilable (< 40 mg.kg -1 ) et N/P 2 O 5 total est supérieur à 2, ce qui est différent de l'optimum (N/P 2 O 5 total = 1,5). Cette étude a permis de montrer que pour les sols sous cacaoyers du Sud-Ouest de la Côte d'Ivoire, une stratégie de fertilisation minérale, en relation avec les systèmes de production doit être adoptée. Mots clés :Fertilité sol, caractéristiques chimiques, cacaoyer, sud-ouest de la Côte d'Ivoire ABSTRACT EVALUATION OF SOILS FERTILITY UNDER CACAO-TREES IN SOUTH-WEST CÔTE D'IVOIREA study was conducted in order to characterize soils fertility under cocoa plantations in South-west Côte d'Ivoire. The study was based on representative soils samples from the Méagui and San-Pedro areas. Soils were sampled under degraded and nondegraded cocoa-trees and also, under uncultivated forest. Each soil sample was analysed in the soils laboratory using standard methods. Multidimensional analyses (ACP and ARH) were used to estimate soil fertility parameters. Results show that soils of the nondegraded cocoa-farms and forest soils (group 1) had organic matter content of more than 3 %, and were more favourable to cocoatrees. These results differ from those obtained with degraded cocoa-trees soils. These soils, represented by groups 1, 2 and 3, were characterized by organic matter contents less favourable to cocoa-trees (< 3 %). In all soils (degraded cocoa farm, nondegraded cocoa farm and forest), the main characteristics of absorbent colloids revealed constraints for cocoa tree developement. All soils were K-deficient K (< 0.2 cmol (+) kg -1 ) ; K content, calculated based on th...

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If the culture of the cocoa in Côte d’Ivoire gives a great satisfaction concerning the production level, the quality of raw cocoa beans remains to be improved. One of the causes of this depreciation is the moulds development in beans. In order to identify responsible fungus, cocoa beens have been collected in the maine production areas which are the East, the Mid-West and the South-West, represented respectively by the localities of Abengourou, Oumé and Soubré. From collected beans, the fungus have been insulated and purified on PDA medium and then, they have been identified by observing their morphocultural and microscopic characteristics. The results show that 9 mushroom species belonging to 5 genera were identified in cocoa beans collected in the whole of the localities. There are Aspergillus, Penicillium, Fusarium, Curvularia and Streptomyces. Among them, the Aspergillus genus which is able to produce ochratoxine, was found with an appearance frequency of 86.30 %.

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Dekoula et al., J. Appl. Biosci. 2018 Variabilité des descripteurs pluviométriques intrasaisonniers à impact agricole dans le bassin cotonnier de Côte d'Ivoire : zones de Boundiali, Korhogo et Ouangolo ABSTRACTObjective: This study aims to characterize the evolution of agricultural impact intra-seasonal descriptors during the growing season in cotton production area of Côte d'Ivoire. For this purpose, Methodology and results: ten intraseasonal descriptors likely to influence agriculture were determined from rainfall data covering the periods 1951-2000 and 2011-2016 from the Airport, Aeronautical and Meteorological Development and Operations Company and the National Agronomic Research Center. Trend (Mann-Kendall) and stationarity (Pettitt) tests and an inter-period comparison were applied to the identified variables. Analysis of seasonal rainfall accumulations, number of rainy days and average daily rainfall amounts showed a significant downward trend over the period 1951-2000. The cessation and length of the rainy season showed a significant trend towards early onset and shortening respectively. Other intraseasonal descriptors do not varied significantly. In contrast, statistically significant breaks were observed between 1968 and 1979. The period comparison indicated a deterioration in conditions during the dry period . The comparison of the periods indicates a deterioration of the climatic conditions during the dry period . These degradations have increased in the current period (2011)(2012)(2013)(2014)(2015)(2016). Conclusion and application: New climatic conditions observed in the cotton production area translated by a variability of intraseasonal descriptors are making agricultural planning increasingly difficult. It is therefore necessary to update the crop calendars in the cotton production area.