I am interested in the use of modelling and statistical techniques to solve problems in plant disease management. Plant disease epidemics are a considerable problem both in natural environments and in commerical agriculture. The overall aim of my work is to inform regulatory and industry decision making. A key focus is the application of probability theory and stochastic modelling to test monitoring and control strategies for invading epidemics. I address practical questions such as: How should we design a monitoring programme to maximise the probability to detect an epidemic soon after it begins? How do we identify and target high-risk areas in a landscape so that an epidemic can be brought under control? How can we be sure that a region is disease free if nothing is detected in a sampling program?

Current projects include work with Defra on the current Ash Dieback epidemic in the UK which is a severe threat to woodland ecosystems across the country. I use spatial-stochastic models to design optimal sampling programs for the early detection of new outbreaks. I also work closely with the US Department of Agriculture on applications such as citrus canker (Xanthomonas axonopodis p.v. citri) and citrus greening (Candidatus Liberibacter spp., syn. Huanglongbing); two pathogens which threaten the continuation of citrus production in the Americas. I am an expert member of the US Citrus Health Response Program (CHRP) and my models are used to direct statewide monitoring programs.

This is Stephen Parnell's profile.