Seth Davis, University of Idaho – Beneficial plant viruses

There can be some surprising benefits to being sick.

Seth Davis, postdoctoral scientist at the University of Idaho, explains how sometimes when a plant gets a virus, it can be a good thing.

Dr. Seth Davis received his B.S. in Forestry, M.S. in Forest Entomology, and Ph.D. in Forest Science from Northern Arizona University, and Dr. Davis worked as a postdoctoral researcher on a large-scale, transdisciplinary climate change project at the University of Idaho before coming to Cal Poly.

Davis’ work is focused on the microbial and chemical ecology of plant-insect interactions in forest and agricultural ecosystems. Research interests in the lab are broad and include population genetics and phenomics of plants and insects. Current projects are related to understanding how pathogens alter the behavior of insect vectors, the role of plant chemistry in mediating ecological dynamics, and the effects of biotic and environmental stress on plant chemical signaling.

Beneficial Plant Viruses

Yes, a virus infection can actually be a good thing for a plant under some conditions! In a biological twist, a virus that damages wheat production worldwide may boost yields of infected plants under drought conditions, our research shows.

Viruses are known for the diseases they cause in humans, animals or crop plants. But there can be other effects, even including some that are beneficial to the infected hosts in certain contexts. These effects can help understand species interactions in ecosystems and identify opportunities to harness the benefits to improve human well being.

Within a large, interdisciplinary project on climate change and wheat production, we began studying the combined effects of drought stress and Barley yellow dwarf virus, which is one of the most serious pathogens of wheat worldwide. How, we asked, might these two stresses interact to affect wheat production?

Seth Davis & Sanford Eigenbrode

In a greenhouse study, we discovered that Barley yellow dwarf virus-infected plants tolerated drought conditions better than uninfected controls, producing more and heavier seeds than non-infected plants when grown with too little water, evidently by causing  plants to retain more water, move photosynthates and grow.

We were surprised, but the finding is consistent with work on drought stress and other plant virus systems. Importantly, though, this effect concerns a world staple so it could have big ramifications.

Adding another level of complexity, Barley yellow dwarf virus is transmitted by aphids, and the infected plants become better hosts for these aphids! This difference is more pronounced when plants are drought stressed. So the effects have implications for pest abundance and for virus spread under climate change.

We are pursuing the mechanisms that produce these effects so that the exciting ecology can inform innovative technology to help with a changing world.