Introduction: Cassava, a key carbohydrate staple in low-income countries, is severely affected by cassava mosaic disease (CMD), primarily transmitted via infected stem cuttings and whiteflies with East African cassava mosaic virus and African cassava mosaic virus (ACMV) being the most significant. ACMV affects all cassava-growing regions of sub-Saharan Africa, India and southern Asia leading to widespread infection rates of 80-100% among crops and yield losses between 20-90%, hence the need to further study the transmission dynamics and possible controls.

Objectives: The objective is to investigate the transmission dynamics and control of CMD by examining the effects of resistant efficacy on infectious cassava. Methods: A deterministic compartmental model governed by a six-dimensional system of ODE was formulated to describe the transmission dynamics and control of CMD between the interacting cassava and whiteflies populations. A piecewise-constant resistant efficacy rate was included to assess its impact on infected cassava transmission dynamics. The control reproduction number, R_e, was calculated using the Next-generation matrix method via Maple. This threshold quantity was used to study the asymptotic behaviours of the disease-free equilibrium (DFE) and endemic equilibrium (EE) of the model. Numerical simulations demonstrated how varying resistant efficacies affect disease dynamics in both susceptible and infectious cassava.

Results: It was found that the DFE (EE) is both locally and globally asymptotically stable whenever R_e<1 (R_e>1) and unstable otherwise. Sensitivity analysis revealed that resistance efficacy and roguing efforts positively influenced the dynamics of CMD.

Conclusion: The results suggest that increasing the resistance efficacy toward 1 significantly reduces new cases of CMD and increasing roguing efforts considerably result to healthier, better quality and quantity of harvested cassava.