Chrysoviruses

Chrysoviridae is a family of dsRNA viruses primarily known as mycoviruses, which infect fungi rather than plants directly. In modern agriculture, their role is significant due to their ability to influence the virulence of various fungal pathogens that threaten crop productivity worldwide.

The virus particles are non-enveloped and possess a segmented genome enclosed within an icosahedral capsid. The transmission mechanism is strictly intracellular, occurring through hyphal anastomosis or through reproductive spores of the host fungus, which limits the dispersal of the virus outside of the fungal population.

Target hosts for these viruses include major agricultural threats such as Fusarium species, Botrytis cinerea, and other pathogens responsible for pre- and post-harvest losses. By residing within these fungi, chrysoviruses can disrupt the metabolic pathways essential for the fungus to cause disease in the host plant.

Symptoms of infection in the fungus include reduced growth rates, altered pigmentation, and impaired conidiation. When a fungus is infected with these viruses, it typically exhibits a state of hypovirulence, meaning its ability to infect or damage the crop is significantly diminished compared to healthy, virus-free strains.

• Monitor fungal disease progression in fields.
• Evaluate the presence of natural mycoviral infections.
• Utilize biological control strategies involving hypovirulent strains.
• Maintain soil health to support diverse microflora.
• Implement crop rotation to disrupt host-pathogen cycles.

Current research emphasizes that utilizing chrysoviruses as biological control agents represents a sustainable approach to plant protection. By encouraging the spread of these viruses among local fungal populations, farmers can potentially reduce the severity of fungal infections without resorting to intensive fungicide applications.