The role of pathogen‐mediated insect superabundance in the East African emergence of a plant virus

Abstract

preceding paper (Donnelly & Gilligan, 2020), we refer to this phenomenon as insect superabundance to signify high incidence at both the individual plant scale as well as the landscape scale (note that some authors prefer to refer to this phenomenon using the terminology of 'insect outbreak', or, simply 'high insect abundance').Superabundance may simply reflect high environmental suitability for the vector (henceforth we call this scenario environmentmediated insect superabundance, EMiS). An alternative cause of superabundance is the invasion of a novel insect vector strain capable of reaching higher abundance than the previously dominant strain (henceforth we call this scenario invasive vector insect superabundance, INViS). An additional cause of superabundance, however, that is independent of environmental suitability and insect invasion, is PMiS (denoting pathogen-mediated insect superabundance), in which pathogen infection improves the resource quality of

Developing a predictive model for an emerging epidemic on cassava in sub-Saharan Africa

“…As with the host landscape, the vector abundance layer provides a single atemporal snapshot, therefore assuming the vector abundance remains stable over time and the different species in the B. tabaci complex are equivalently capable of transmitting CBSIs. There is an ongoing debate over the extent to which there is an interaction between the cassava epidemics of CBSD and cassava mosaic disease (CMD) and changes in local vector abundance or the specific abundance of species within the B. tabaci complex 34,35 . Extensive experimental and modelling work would be necessary to improve our understanding of the significance of the local composition and abundance of the B. tabaci species complex on the spread of the epidemic.…”

Developing a predictive model for an emerging epidemic on cassava in sub-Saharan Africa

“…As with the host landscape, the vector abundance layer provides a single atemporal snapshot, therefore assuming the vector abundance remains stable over time and the different species in the B. tabaci complex are equivalently capable of transmitting CBSIs. There is an ongoing debate over the extent to which there is an interaction between the cassava epidemics of CBSD and cassava mosaic disease (CMD) and changes in local vector abundance or the specific abundance of species within the B. tabaci complex [33, 34]. Extensive experimental and modelling work would be necessary to improve our understanding of the significance of the local composition and abundance of the B. tabaci species complex on the spread of the epidemic.…”

A new method for the analysis of access period experiments, illustrated with whitefly-borne cassava mosaic begomovirus

“…no epidemic growth. Furthermore, elevated B. tabaci abundance has been repeatedly observed in combination with severely diseased cassava [14]-and this has been linked to a synergistic interaction between the vector and the pathogen [15][16][17][18][19]. These considerations mean that a reappraisal of the transmission efficiency of CMB-carrying whitefly is now timely.…”