Asymmetrical over-infection as a process of plant virus emergence

作者：Fabre Frederic^*; Chadoeuf Joel; Costa Caroline; Lecoq Herve; De**iez Cecile

来源：Journal of Theoretical Biology, 2010, 265(3): 377-388.

DOI：10.1016/j.jtbi.2010.04.027

• Biological invasion
• Epidemiology
• Landscape
• State-space model
• Watermelon mosaic virus

Disentangling the role of epidemiological factors in plant pathogen emergences is a prerequisite to identify the most likely future invaders. An example of emergence was recently observed in France: in 10 years, "classic" (CL) strains of Watermelon mosaic virus (WMV) were displaced at a regional scale by newly introduced "emerging" (EM) strains. Here we analyse a 3 years dataset describing the co-dynamics of CL and EM strains at field scale using state-space models estimating jointly: (i) probabilities of primary and secondary infection and (ii) probabilities of over-infecting with a CL [EM] strain a plant already infected with an EM [CL] strain. Results especially indicate that it is more than 3 times less probable for a CL strain to over-infect an EM infected plant than for an EM strain to over-infect a CL infected plant. To investigate if these asymmetric interactions can explain the CL/EM shift observed at regional scale, an exploratory model describing WMV epidemiology over several years in a landscape composed of a reservoir and a cultivated compartment is introduced. In most simulations a shift is observed and both strains do coexist in the landscape, reaching an equilibrium that depends on the probabilities of over-infection.

• 出版日期2010-8-7