COS 293-4 - CANCELLED - Hosts, humans and viruses: characterizing a prevalent wild plant-virus interaction across anthropogenic disturbance clines

Abstract: Interactions between plants and viruses have ecological and evolutionary implications for wild plant hosts and cultivated crop species. However, virus diversity is not well characterized across wild plant groups, and interdisciplinary methods are necessary to identify mechanisms that structure plant-associated virus biodiversity and distributions. Here we present the first comprehensive study of a widespread plant-virus interaction and identify humans as critical facilitators in the spread of turnip mosaic virus (TuMV) across populations of the wild host Hesperis matronalis. Our study addresses the hypotheses that i) TuMV induces visible disease symptoms in H. matronalis, ii) wild hosts have evolved genetic tolerance to TuMV infection and iii) human aesthetic preferences have facilitated the persistence of TuMV in wild H. matronalis populations. We address these questions using interdisciplinary methods including molecular and genomic analyses of virus communities, experimental infection trials, spatial modeling and focus group surveys of stakeholder communities.

Enzyme-linked immunosorbent assays (ELISA) and deep sequencing of RNA virus communities from wild collected H. matronalis tissue confirm that TuMV is prevalent across upstate New York. Results from experimental infection trials show that TuMV infection induces disease symptoms including leaf mottle and color breaking petals, indicating a causative relationship between TuMV and observable phenotypic changes. Furthermore, these experimental infection studies were conducted under common garden conditions, and we show that there is genetic tolerance to TuMV that varies between host genotypes. In order to determine how widespread this plant-virus symbiosis is across North America, we constructed predictive virus distribution models using host and virus presence data from across abiotic and anthropogenic environmental clines. Model results indicate that host density and human-associated land impacts are more important than abiotic conditions for predicting the distribution of TuMV in wild H. matronalis populations. This result, along with evidence of variable host tolerance, motivates future surveys to characterize virus prevalence and consequences from the center of the TuMV-Hesperis range in the Great Lakes region to expanding western and northern edges. Finally, we engaged with socioecological data and local stakeholders to study potential mechanisms through which humans interact with the widespread TuMV-Hesperis pathosystem, and show that anthropogenic land use and aesthetic preferences facilitate virus persistence. Overall, this study unites diverse methodological approaches to characterize the extent of a prevalent plant virus across heterogenous landscapes and between host populations.