This study, conducted in Akressi, Côte d’Ivoire, assesses the impact of cover crops (Arachis repens and Desmodium adscendens) on soil properties and dessert banana production (Cavendish, Grande-Naine) over two cycles. Ferralitic soils, degraded by intensive monoculture, are examined using a Fischer block design with three treatments: control (bare soil with herbicides), A. repens, and D. adscendens. Soil physical properties (bulk density: 1.90–1.94 g/cm3, porosity: 25.15–27.18%, gravimetric moisture: 17.34–21.58%) remain unchanged (p > 0.05). After 12 months, cover crops enhance chemical properties: pH (5.80 control, 6.03 A. repens, 5.93 D. adscendens), organic carbon (1.11% control, 1.24% A. repens, 1.38% D. adscendens), organic matter (1.90% control, 2.13% A. repens, 2.37% D. adscendens), nitrogen (0.10% control, 0.11% A. repens, 0.12% D. adscendens), CEC (5.38 cmol/kg control, 7.20 cmol/kg A. repens, 8.61 cmol/kg D. adscendens), and calcium (1.56 cmol/kg control, 1.66 cmol/kg A. repens, 1.75 cmol/kg D. adscendens) increase significantly (p < 0.05). In the first cycle, growth (height: 245–247 cm) and yield (41.21–42.08 t/ha) are similar (p > 0.05). In the second cycle, control plants are taller (271.76 cm vs. 255.36 cm A. repens); A. repens delays flowering (158 vs. 135 days) and harvest (235 vs. 214 days D. adscendens) and reduces functional leaves (10.84 vs. 11.66 control at flowering) (p < 0.01). Desmodium adscendens increases hands (7.82 vs. 7.33 A. repens) and fingers (140.57 vs. 127.10 A. repens) (p < 0.05). Yields remain comparable (44.17 control, 44.36 A. repens, 44.50 t/ha D. adscendens). Cover crops, particularly D. adscendens, enhance soil chemical fertility without compromising yield, supporting sustainable banana production.
The stem borer Eldana saccharina infestation level on Borotou-Koro sugar complex is very alarming. However, effective control methods are not yet very developed against this pest. In order to better understand and guide the search for a lasting solution, it is necessary to master the biology and ecology of this insect pest. It is in this context that this study was conducted at Borotou-Koro agricultural integrated unit. It aims to inventory the natural enemies of Eldana saccharina, in this case the parasitoids present on the sugarcane plots. To do this, borer larvae and pupae were collected from the sugarcane plots and reared in the laboratory. The results obtained indicate that three Lepidoptera species of stem borer are present on the Borotou-Koro sugar complex: Eldana saccharina (98.4%), Sesamia calamistis (1.53%) and Sesamia inferens (0.07%). The parasitism rate of E. saccharina larvae and pupae is low (3.29%). Six species of parasitoid auxiliaries of Eldana saccharina have been identified including a larval parasitoid (Sphaephoria sp), a larval-pupae parasitoid (Lycoriela auripila) and four pupae parasitoids (Trichopeza sp, Proctotrupes sp, Proconura nigripes, Psilochalcis sp). Fusarium spp has also been identified as a parasite of Eldana saccharina larvae. These six parasitoid species come from two families which are the Diptera estimated at 3.32% and the Hymenoptera which represents 96.68% of the percentage of parasitoids encountered. Thus, the Borotou-Koro sugar complex is full of several species of Eldana saccharina parasitoids on these sugarcane plots. Eldana saccharina larvae and pupae rate of parasitism is substantially identical for all the varieties of cane encountered. However, the parasitism rate of pupae varies greatly from one sector to another and is higher in rainfed conditions than in irrigated conditions.