Vector-transmitted diseases of plants have had devastating effects on agricultural production worldwide, resulting in drastic reductions in yield for crops such as cotton, soybean, tomato, and cassava. Plant-vector-virus models with continuous replanting are investigated in terms of the effects of selection of cuttings, roguing, and insecticide use on disease prevalence in plants. Previous models are extended to include two replanting strategies: frequencyreplanting and abundance-replanting. In frequency-replanting, replanting of infected cuttings depends on the selection frequency parameter ε, whereas in abundance-replanting, replanting depends on plant abundance via a selection rate parameter also denoted as ε. The two models are analysed and new thresholds for disease elimination are defined for each model. Parameter values for cassava, whiteflies, and African cassava mosaic virus serve as a case study. A numerical sensitivity analysis illustrates how the equilibrium densities of healthy and infected plants vary with parameter values. Optimal control theory is used to investigate the effects of roguing and insecticide use with a goal of maximizing the healthy plants that are harvested. Differences in the control strategies in the two models are seen for large values of ε. Also, the combined strategy of roguing and insecticide use performs better than a single control.

媒介传播的植物病害已对全世界的农业生产造成了毁灭性影响，导致棉花，大豆，番茄和木薯等农作物的产量大幅度下降。在选择插条，生熟和使用杀虫剂对植物疾病流行的影响方面，研究了具有连续补植的植物-载体-病毒模型。先前的模型已扩展为包括两种重新种植策略：频率重新种植和丰度重新种植。在频率补种中，受感染插条的补种取决于选择频率参数ε，而在丰度补种中，补种取决于通过选择率参数（也称为ε）的植物丰度。 分析了两个模型，并为每个模型定义了消除疾病的新阈值。木薯，粉虱和非洲木薯花叶病毒的参数值用作案例研究。数值敏感性分析说明了健康植物和受感染植物的平衡密度如何随参数值变化。最佳控制理论用于调查流氓和杀虫剂使用的影响，目的是最大限度地提高收获的健康植物。对于较大的ε值，可以看到两个模型中控制策略的差异。 同样，流氓和杀虫剂组合使用的策略比单个控件要好。