This study aims to evaluate the effects of two leguminous plants Arachis repens and Desmodium adscendens, used as cover crops, on the proliferation of arbuscular mycorrhizal (AM) fungal spores in soils under industrial banana plantations. Soil samples were collected at two depths (0-10 cm and 10-20 cm) before, 6 and 12 months after the cover crops installation in a three-treatment Fisher block design. After laboratory analysis of the collected soil samples, the results showed that A. repens strongly contributed to the increase of AM fungal spores. Indeed, before planting this legume, the average number of spores which was 882.50 at 0-10 cm of the soil, increased to 1502.50 and then to 2390.00 in 100 g of soil respectively after 6 and 12 months. At the depth of 10-20 cm, the number of spores was 790.00, 1177.50 and 1270 spores/100 g soil, respectively. Acaulospora, Gigaspora, Glomus and Scutellospora were the main genus obtained among the identified spores. Among them, Glomus and Acaulospora were the most abundant. A. repens could be used as a cover crops for the sustainable management of biological soil fertility.

Coffee is a crop that exports significant amounts of minerals from the soil, particularly through crop and pruning products. Maintaining sustainable productivity requires good knowledge and rational management of factors related to soil fertility and plant nutritional status, which would limit production. The objective of this study was to diagnose the mineral requirements of coffee plants in different production regions in order to recommend nutrient quantities adapted to the characteristics of each soil type for sustainable coffee production. Chemical analysis of 156 soil samples representative of the soil units of the coffee growing areas using a soil diagnostic model specific to coffee fertilization was used to determine the nutrient requirements of each soil unit studied. The results generally indicate that soil fertility levels were below the reference threshold values. Nutrient inputs are essential for all soils under coffee in large production areas. Nitrogen inputs are required in all soil units studied. The majority of the soils also showed a very pronounced potassium and calcium deficiency, while the phosphorus deficiency was not very pronounced. Magnesium, although generally in sufficient quantity in soils, has been readjusted to respect the balance in exchangeable bases. The amounts of nutrients to be supplied varied from one soil unit to another. Soils with low organic matter content showed relatively high requirements. Recommendations for appropriate soil fertility management per soil unit were presented in this work.

In the search for alternative practices to the excessive use of herbicides for control of weediness, strategies based on the domestication and multiplication of cover crops are more and more explored. The propagation by cuttingof these plants have been the subject of numerous studies because of unavailability andcost-prohibitive of their seeds. The aim of this study was to compare the growthandcuttingabilityofA. repens, A. pintoï and D.adscendens. These cover plants were propagated by cutting in coir and put on raised bamboo clays with shade, in greenhouse. For each specie, parameters of vegetative recovery and growth were assessed. The results reported that recovery abilities were most important toA. pintoï (89.35%) and A. repens (86.39%). However, plant growth was better for D. adscendens, with a vigour index more than double with that ofboth theother species. The results obtained show that these three cover crop species are relatively easy to propagate by cutting in nursery.D. adscendens and A. repens are potentially usable in large scaleas cover cropstocontrol weeds in agricultural parcels.

Coffee production in Côte d'Ivoire has been declining sharply for more than twenty years due to degradation in soil fertility status. The objective of this study was to map the mineral requirements of coffee trees in different production regions and to recommend immediate and long-term intervention strategies for soil management. In this study, the diagnosis of the chemical needs of 156 soil samples from major coffee production areas was used. We used a soil diagnostic model specific to coffee fertilization combined with geographic information systems (GIS). The combination of fertilizer formulas from the coffee soil diagnostic model, recent climatic data and soil units of the coffee growing areas allowed the elaboration of a thematic map showing a total of five basic formulas (N-P2O5-K2O-CaO-MgO) adapted to the real nutritional needs of coffee trees according to their agropedoclimatic environments. Two of these formulas cover 90% of the area studied. This study will enable appropriate soil management for the sustainable productivity of coffee trees in Côte d'Ivoire.

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