Effect of rice/cassava rotation on agronomic parameters of rice and cassava grown on Ferralsol in western Côte d'Ivoire

The rice/cassava rotation is one of the dominant rice-based cropping systems in western Côte d'Ivoire due to the inaccessibility of chemical fertilisers. The low productivity of this cropping system makes it necessary to think about improving agronomic performance. The objective of this study is to determine the effect of the rice/cassava rotation on the agronomic parameters of these crops. To achieve this objective, an agronomic trial was set up at the CNRA Research Station in Man on a Ferralsol. Five cropping sequences were compared in a Fischer block design with 5 treatments and 4 replications: 2 intensive monocultures of rice (0.20 m × 0.20 m) and cassava (1 m × 1 m) and 3 alternations of rice and cassava (R/M/R, M/R/M and R/R/M (farmer control)). The parameters measured were height, tillering, and yield of rice and cassava, as well as soil chemical parameters. The results showed that rice in rotation with cassava had a significant effect on cassava production, while cassava had no significant effect on rice grain yield. The rice-cassava rotation harmed soil chemical parameters. Except for the improvement of nitrogen and phosphorus contents due to biochemical reactions in the rhizosphere and the mobility of nutrients along the fertility gradient. Finally, R/M/R was found to be the best cropping sequence in a rice-based cropping system.