Colletotrichum betachrysovirus

Betachrysovirus colletotrichi is a double-stranded RNA mycovirus that specifically infects fungi of the Colletotrichum genus. As a mycovirus, it does not attack plants directly but instead infects the fungal pathogen responsible for anthracnose disease, making it a subject of significant interest in the field of biological plant protection.

This virus targets various Colletotrichum species, which are known to cause severe damage to a wide range of crops, including strawberries, legumes, cereals, and trees. These fungi typically cause localized lesions, rotting of fruits, and blighting of stems, leading to severe economic losses in both open-field and greenhouse production.

The presence of Betachrysovirus colletotrichi induces physiological changes in the fungal host, a phenomenon often described as hypovirulence. Symptoms within the fungal colony include reduced mycelial growth rates, diminished pigment production, and a significant decrease in sporulation capacity, which limits the fungus's ability to infect new plant hosts.

Development and spread of the virus within fungal populations occur primarily through vegetative compatibility, where the virus is transmitted between hyphae during anastomosis. Environmental conditions that favor the proliferation of Colletotrichum, such as high humidity and moderate temperatures, also facilitate the rapid spread of the virus throughout the pathogenic fungal population.

The potential for using this mycovirus in agriculture revolves around the concept of biological control. Key aspects of managing fungal diseases using this approach include:

• Reducing the aggressiveness and virulence of the pathogen.
• Deploying hypovirulent strains to outcompete natural pathogenic populations.
• Enhancing natural disease suppression in soil and plant surfaces.
• Developing sustainable biological control agents to reduce fungicide reliance.

Effective prevention and protection against anthracnose still require a multi-faceted approach. While mycoviruses offer promise for long-term biocontrol, agronomists should prioritize crop rotation, sanitizing agricultural tools, removing crop residues, and using certified disease-free seeds to minimize the pressure of fungal diseases.