Vermicompost as an Alternative to Inorganic Fertilizer to Improve Okra Productivity in Côte d’Ivoire

Abstract
Okra is one of the most popular vegetables in Côte d’Ivoire which is produced by heavy use of inorganic fertilizers. Vermicompost can be an alternative to inorganic fertilizers. This field study investigated the effect of vermicompost on growth and productivity of okra as compared to inorganic fertilizers. The respective treatments were arranged in a complete randomized block design, each at three replications, during three-season cycles on a ferralitic soil. Results showed that the highest rate of germination was obtained with the vermicompost. The tallest plants of Abelmoschus esculentus (1.88 m) and Abelmoschus caillei (1.78 m) were observed with inorganic fertilizer. The number of leaves per plant registered when using vermicompost was 34.5 and 30.74 with Abelmoschus esculentus and Abelmoschus cailli, respectively. With inorganic fertilizer, the number of leaves per plant was 34.21 (Abelmoschus esculentus) and 32.32 (Abelmoschus cailli). Plants took about 60 days to flower in the control plots and about 46 days in the plots fertilized with the vermicompost and the inorganic fertilizer. The highest pod yields of Abelmoschus esculentus and Abelmoschus cailli were 8.7 t⋅ha−1 and 10.58 t⋅ha−1 with vermicompost and 8.85 t⋅ha−1 and 10.7 t⋅ha−1 with inorganic fertilizer, respectively. Vermicompost could be recommended as an alternative to inorganic fertilizer to produce okra on ferralitic soil in Côte d’Ivoire.