Valorizing Carbonized Rice Husk Material for Improving Maize Vegetative Growth in Northern Côte d’Ivoire

Abstract

The valorisation of agricultural residues offers opportunities for developing more sustainable fertilisation practices. This study was conducted in Mankono, Béré Region, northern Côte d’Ivoire, in 2022 from the end of the long rainy season (July to September) followed by the transition to the long dry season (October to November). This research aimed to evaluate the effects of a carbonised material, produced by heating rice husks in a furnace for three hours under limited air supply, on maize vegetative growth. The field experiment was conducted using a Fisher block design with four treatments and four replications: T0 (unfertilised control), T1 (50 g of carbonised rice husks per plant), T2 (100 g of carbonised rice husks per plant), and T3 (mineral fertilisation). Stem length, plant height, stem diameter, and number of leaves were measured at eight different intervals during the growing cycle. The results revealed significant differences among treatments in stem length and plant height, with mineral fertilisation generally producing the highest values. Treatment T2 showed intermediate performance and improved several vegetative growth parameters as compared to the unfertilised control at different measurement dates. For leaf number, T2 and T3 did not differ significantly at the final observation. In contrast, no significant variation was observed among the treatments for the stem diameter. Overall, the application rate of 100 g of carbonised material per plant showed the greatest potential among the two rates tested, although its performance did not consistently match that of mineral fertilisation. These findings highlight the potential value of rice husk valorisation for maize production while supporting further research into the physicochemical properties of the material, soil characteristics, and crop yield.