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A mathematical model for Banana Xanthomonas Wilt (BXW) spread by insect vector is presented. The model incorporates inflorescence infection and vertical transmission from the mother corm to attached suckers, but not tool-based transmission by humans. Expressions for the basic reproduction number $R_0$ are obtained and it is verified that disease persists, at a unique endemic level, when $R_0>1$. From sensitivity analysis, inflorescence infection rate and roguing rate were the parameters with most influence on disease persistence and equilibrium level. Vertical transmission parameters had less effect on persistence threshold values. Parameters were approximately estimated from field data. The model indicates that single stem removal is a feasible approach to eradication if spread is mainly via inflorescence infection. This requires continuous surveillance and debudding such that a 50% reduction in inflorescence infection and 2–3 weeks interval of surveillance would eventually lead to full recovery of banana plantations and hence improved production.

Roguing and replanting is a widely accepted control strategy of infectious diseases with limited reproduction capacity in orchards. Little is known about the effects of this type of management on the dynamics of the infectious disease. In this paper we analyze a model for the dynamics of a S-I-R type epidemic under roguing and replanting. The model is structured with respect to the number of infections on a tree. Trees are assumed to be rogued, and replaced by uninfected trees, when the number of infections on the tree reaches a threshold value, L_max. It is shown that increasing L_max can lead to large amplitude periodic fluctuations in the infectious disease and the number of trees rogued per year. We compare the L_max which leads to periodic solutions, with the final value, L_∞, theorem of the classical Kermak and McKendrick model. It is shown that the non-trivial steady state is stable if L_max<L_∞. Periodic solutions can only arise when L_max>L_∞. A biological interpretation of this result is given.