Many important plant diseases are vectored by insects, and the dependence of pathogens and insect herbivores on a common plant host creates the potential for antagonistic and mutualistic interactions that may have large implications for disease transmission. Pathogen-induced effects on plant traits affecting their suitability for herbivores or the cues presented to foraging insects are likely to be central to these interactions. Yet, the ecology and evolution of plant-pathogen-vector interactions is not well understood. A few recent studies have shown that virus-induced plant organic volatiles are attractive to aphid vectors, but broader implications for disease ecology and pathogen evolution have not been investigated. I propose here to explore the ecology of vector-borne viral and bacterial pathogens of the wild gourd Cucurbita pepo subsp. texana. Previous work in this system suggests that infection by an aphid-vectored virus, ZYMV, and a beetle-vectored bacterial pathogen, Erwinia trachephila, are dependent on the selective behaviour of their respective vectors. I will thus explore the effects of pathogen-induced changes in plant volatiles and insect behaviour, and their impact on pathogen transmission. I will examine variation within natural pathogen populations for these effects, to gain a better understanding of their adaptive nature and their consequences in pathogen epidemiology and evolution. I will also develop a second study system, involving the plant Arabidopsis thaliana and a whitefly-vectored virus (CaMV) to extend this valuable model to questions relating to plant-pathogen-vector interactions, which would greatly facilitate the elucidation of underlying mechanisms. The proposed work will be performed jointly at the department of entomology of the Pennsylvania State University, USA, a worldwide leader in the fields of chemical ecology and disease dynamics, and the laboratoire Ecologie, Systématique et Evolution at Université Paris-Sud 11, France.
Fields of science
Call for proposal
See other projects for this call