Characterization of the Agronomic Properties of Different Vermicompost from the Co-composting of Oil Palm Empty Fruit Bunches and Green Waste

The accumulation of palm oil industries waste is one of the causes of environmental pollution that is becoming an increasingly concern in Côte d'Ivoire. However, this waste, combined with other simple plant substrates, can be used in the vermicomposting process. That is the context in which this study is conducted, with the aim of determining the agronomic properties of different vermicompost made of oil palm empty fruit bunches combined with green waste (Chromolaena odorata leaves and grass clippings). For this purpose, plastic boxes of 1.5 L in volume were first filled with 800 g of soil. Then, 300 g of the different pre-composted substrates and 4 earthworms were added. In total, 4 treatments of 25 repetitions each were carried out. For all the treatments, treatments T3 (oil palm empty fruit bunches + Grass cutting + earthworms) and T4 (oil palm empty fruit bunches + Chromolaena odorata + Grass cutting + earthworms) presented the best values of the substrate decomposition capacity and physicochemical properties. The same is true for the mineral materials obtained. For these two treatments mentioned, the C/N ratio was around 15 and significantly higher than those of treatments T1 (oil palm empty fruit bunches + earthworms) and T2 (oil palm empty fruit bunches + Chromolaena odorata + earthworms), which were around 12. The pH values being variable at the beginning of vermicomposting were close to neutral at the end, thus indicating the maturity of the different vermicompost produced. Vermicompost resulting from co-composting of empty fruit bunches of oil palms and green waste appears to improve nutrient availability, structure and microbial activity of the vermicompost to promote good development of cultivated plants.