Panicum mosaic virus

Panicum mosaic virus (Panicovirus panici) is a viral plant pathogen that primarily affects members of the Poaceae family. As a systemic disease, it infiltrates the vascular system of the host plant, severely disrupting metabolic functions, nutrient transport, and overall development, leading to substantial yield losses in agricultural settings.

The primary host for this virus is proso millet (Panicum miliaceum). However, the virus has a broad host range, infecting various species of wild grasses. These wild grasses serve as an essential reservoir, allowing the virus to survive throughout the winter and infect new crops during the growing season.

Symptoms of the infection typically include a mosaic pattern on the leaves, characterized by light green and yellow chlorotic streaks. Infected plants often exhibit stunted growth, reduced tillering, and distorted leaf blades. In severe cases, the panicles fail to develop properly, leading to sterility or shriveled, low-quality grains that significantly diminish the harvest.

The virus is primarily transmitted by insect vectors, specifically aphids and leafhoppers. These insects acquire the virus by feeding on infected plant tissues and subsequently transmit it to healthy plants during the probing and feeding process. The environmental conditions favoring the proliferation of these insect populations are the primary drivers of rapid disease transmission within a field.

Managing Panicum mosaic virus requires an integrated approach, as there are no direct chemical treatments to cure the viral infection once it has established. Effective strategies include:

• Rigorous management of insect vectors using appropriate insecticides.
• Eliminating weeds and alternate grass hosts in and around the planting area.
• Planting resistant or tolerant cultivars when available.
• Implementing crop rotation to prevent the buildup of viral inoculum in the soil or local ecosystem.