Three aphid-transmitted viruses encourage vector migration from infected common bean (Phaseolus vulgaris) plants
Through a combination of volatile and surface cues
Abstract
Bean common mosaic virus (BCMV), bean common mosaic necrosis virus (BCMNV), and cucumber mosaic virus (CMV) are important pathogens of common bean (Phaseolus vulgaris), a crop vital for food security in sub-Saharan Africa. These viruses are vectored by aphids non-persistently, with virions bound loosely to stylet receptors. These viruses also manipulate aphid-mediated transmission by altering host properties. Virus-induced effects on host-aphid interactions were investigated using choice test (migration) assays, olfactometry, and analysis of insect-perceivable volatile organic compounds (VOCs) using gas chromatography (GC)-coupled mass spectrometry, and GC-coupled electroantennography. When allowed to choose freely between infected and uninfected plants, aphids of the legume specialist species Aphis fabae, and of the generalist species Myzus persicae, were repelled by plants infected with BCMV, BCMNV, or CMV. However, in olfactometer experiments with A. fabae, only the VOCs emitted by BCMNV-infected plants repelled aphids. Although BCMV, BCMNV, and CMV each induced distinctive changes in emission of aphid-perceivable volatiles, all three suppressed emission of an attractant sesquiterpene, α-copaene, suggesting these three different viruses promote migration of virus-bearing aphids in a similar fashion.
This is a publication arising from the Sustainable Crop production for International Development (SCPRID) programme.
Citation
Wamonje F, Tungadi T, Murphy A, Pate A, Woodcock C, Caulfield J, Mutuku M, Cunniffe N, Bruce T, Gilligan C, Pickett J, Carr J (2020). Three aphid-transmitted viruses encourage vector migration from infected common bean (Phaseolus vulgaris) plants through a combination of volatile and surface cues. Front Plant Sci 11:1981.