Frontiers in Fungal Virus Research

Since the first discovery of mycoviruses from diseased mushroom in the early sixties, there have been extensive efforts to characterize and study mycoviruses infecting diverse fungi or fungal-like organisms including yeast, filamentous fungi and oomycetes. Representative hosts include Rosellinia spp., Fusarium spp., Sclerotinia spp. and Aspergillus spp. The characterization of a large numbers of newly discovered mycoviruses greatly enriches our knowledge of the great diversity of genome organization, virus structure, replication and gene expression strategy and transmission. The recent advent of metagenomics has further uncovered the prevalence and ecological diversities of mycoviruses in different environments. As fungi are the major causative agents for plant disease in agricultural production, research on mycoviruses is especially important, owing to the possibility of using mycoviruses as biocontrol agents for phytopathogenic fungi (as exemplified by the successful control of chestnut blight disease with hypovirus). Many mycoviruses could alter the morphology and physiology of their hosts, thus they could be used as probes into fungal morphogenesis, virulence, hyphal anastomosis, sexual crosses, asexual sporulation, metabolite synthesis and modulation of fungal-plant interactions. Moreover, some virus/host combinations such as the Cryphonectiaparasitica/viruses and Saccharomyces cerevisiae/viruses are established as an experimental model system to study virus-host and virus-virus interactions. The use of fungi as model virus hosts provides some advantages. For example, they are easily grown in artificial conditions, have a short life cycle, efficient genome manipulation methods are widely available and successful virus elimination/introduction has been achieved for some virus-fungus pathosystems.

This Research Topic widely covers the recent research findings on the study of mycoviruses encompassing all aspects of basic virology, virus-host interactions, virus evolution, virus ecology and the implementations of this knowledge for development of biological control of fungal crop diseases. We welcome the submission of original research papers as well as reviews describing any advancement in the studies on mycoviruses.