Disease control and its selection for damaging plant virus strains in vegetatively propagated staple food crops; a theoretical assessment

Abstract

Viral diseases are a key constraint in the production of staple food crops in lesser developed countries. New and improved disease control methods are developed and implemented without consideration of the selective pressure they impose on the virus. In this paper, we analyse the evolution of within-plant virus titre as a response to the implementation of a range of disease control methods. We show that the development of new and improved disease control methods for viral diseases of vegetatively propagated staple food crops ought to take the evolutionary responses of the virus into consideration. Not doing so leads to a risk of failure, which can result in considerable economic losses and increased poverty. Specifically in vitro propagation, diagnostics and breeding methods carry a risk of failure due to the selection for virus strains that build up a high within-plant virus titre. For vegetatively propagated crops, sanitation by roguing has a low risk of failure owing to its combination of selecting for low virus titre strains as well as increasing healthy crop density.

Vector preference and host defense against infection interact to determine disease dynamics

“…In agriculture, the development and use of better defended varieties or breeds is a common strategy for disease management (van den Bosch et al 2006, 2007). Following the recommendations of van den Bosch et al (2007), our results indicate that understanding the precise form of defense is critical for disease management. This is particularly true for vector‐borne pathogens, where vector behavior may accentuate epidemiological differences in the effects of host defense on pathogen spread.…”

Modeling and Analysis of Integrated Pest Control Strategies via Impulsive Differential Equations

“…On the other hand, another parameter considered in the ecosystem is the within-plant virus titre (denoted hereafter by ). As pointed out in [32], this parameter deeply influences both the viral transmission in the crops and the corresponding disease symptoms, which in turn affect the roguing rates and recovery and detection probabilities. Therefore, van den Bosch et al assume the parameters , , , and to be -dependent, and they suggest certain functional relations to quantify these interactions, motivated by some previous field studies.…”

“…A low-dimensional model considering cultural practices as the only disease control action is proposed by van den Bosch et al [32]:…”

A Plant Virus Disease Model with Periodic Environment and Pulse Roguing

“…Mathematical models for plant virus diseases have been proposed to describe, analyze, and predict epidemics of plant diseases for the ultimate purposes of developing and testing control strategies and tactics for plant protection . A mathematical model was studied by Fishman et al.…”