Mycoviruses: trends in plant-fungus-mycovirus interactions and ‘biocontrol’ prospects in agriculture and the environment

Mycoviruses are cosmopolitan in plants, animals, fungi, bacteria, in soils, and water. There is a scarcity of information about them, which necessitated this review to provide some leads on where research should focus. Mycoviruses are able to persist in disparate types of hosts by utilizing diverse measures. They may engage either parasitic, pathogenic, or mutualistic tendencies. Mycoviruses employ many existential strategies that can be utilized by man. Hypovirulence may be induced in fungal hosts by mycoviruses via RNA silencing, alteration of genetic expression, and disruption of the transcriptome. Mycoviruses interact with killer phenotypes of yeasts and Ustilago spp. and proffer advantages to these fungi. Mycovirus interaction with some plants result in provision of thermal tolerance to plants. Based on their mode of microbe destruction mycoviruses may be used for waste disposal and termination of some life processes. For instance, grazer viruses completely oxidize the organic content of their host into carbon dioxide and inorganic nutrients, while lytic viruses release the organic material from their hosts without modification. Viruses may be utilized to facilitate the exchange of genetic material from one host to another. However, pathogenic mycoviruses exist especially in mushrooms.