The role of viruses in the phytobiome

Authors: SCHOELZ, JAMES - University Of Missouri; Stewart, Lucy

Submitted to: Annual Review of Virology
Publication Type: Review Article
Publication Acceptance Date: 6/14/2018
Publication Date: 7/26/2018
Citation: Schoelz, J.E., Stewart, L.R. 2018. The role of viruses in the phytobiome. Annual Review of Virology. 5:93-111. https://doi.org/10.1146/annurev-virology-092917-043421.
DOI: https://doi.org/10.1146/annurev-virology-092917-043421

Interpretive Summary: The role of viruses in the phytobiome, which is defined by the American Phytopathological Society as "plants, their environment, and their associated communities of organisms" is reviewed. Within the phytobiome, the importance of microbial communities for plant health including nutrient uptake and resistance to disease are increasingly of interest in agriculture and agricultural research. Viruses also impact plant health by infecting all the biotic components of the phytobiome, including soil bacteria, nematodes, arthropods including those that vector plant-infecting viruses, and plant-associated fungi. However, the impacts of viruses on components of and the entire phytobiome can be more difficult to experimentally study, although research so far shows their impact (not always detrimental) on plant biotic and abiotic interactions and in plant-insect-virus interactions, and in hypovirulence of phytopathogenic fungi. This article reviews current information on the impact and role of viruses on the phytobiome and on plant health, which is likely to be important although currently understudied, and is of interest to virologists and plant biologists interested in the phytobiome.

Technical Abstract: Viruses are an important but sequence-diverse and often understudied component of the phytobiome. We succinctly review current information on how plant viruses affect plant health and physiology directly, and consequently have the capacity to modulate plant interactions with their biotic and abiotic environments. Virus interactions with other biota in the phytobiome, incuding arthropods, fungi and nematodes, may demonstrably or hypothetically affect plant health. For example, viruses interact with and modulate the interface between plants and insects. This has been extensively studied for insect-vectored plant viruses, some of which also infect their vectors. Other viruses have been shown to alter the impacts of plant-interacting phytopathogenic and nonpathogenic fungi and bacteria. Viruses infecting nematodes have also recently been discovered, but the impact of these and phage infecting soil bacteria on plant health remain largely unexplored.