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.

Cassava mosaic disease and its whitefly vector in Cameroon: Incidence, severity and whitefly numbers from field surveys

“…However, the lowest whitefly mean count was recorded on plants with the highest severity score. This could be because virus-infected cassava leaves may be repellent to or present an unattractive environment for whitefly settling as it has been reported in other systems ( Wamonje et al, 2020 ).…”

Transcriptional and functional predictors of potato virus Y-induced tuber necrosis in potato (Solanum tuberosum)

“…Four biological processes, isoprenoid biosynthetic process, isoprenoid metabolic process, terpenoid metabolic process, and terpenoid biosynthetic process, participate in terpenoid metabolism. Terpenoids mediate plant responses to biotic and abiotic factors ( Tholl, 2006 ; Nagegowda, 2010 ), including fine-tuning host–vector–virus interactions to facilitate vector transmission ( Wamonje et al., 2020 ), and the cellular environment for viral replication ( Wu et al., 2019 ). Thus, the observed repression of these terpenoid-related processes could modulate aphid transmission and pathology of PVY in a similar fashion.…”

Epidemiological and ecological consequences of virus manipulation of host and vector in plant virus transmission

“…Interactions between vectors and non-vector herbivores and pollinators, and other tritrophic interactions can also affect virus spread [56,[85][86][87][88][89][90][91][92]. Links with vector-natural enemy associations have also been confirmed [93,94].…”