Panicum streak virus

The causal agent of this disease is the Panicum streak virus, classified within the genus Mastrevirus of the Geminiviridae family. As a single-stranded DNA virus, it targets monocotyledonous plants, leading to systemic infection that disrupts essential physiological functions, primarily affecting photosynthesis and plant development.

The primary hosts for this virus are various species within the Panicum genus, along with several wild grass species. These wild grasses often act as critical reservoirs for the pathogen, allowing the virus to survive and persist in the environment even when cultivated host crops are absent from the field.

Key symptoms include the development of distinct chlorotic stripes running parallel to the leaf veins. As the disease progresses, these stripes may coalesce, causing significant yellowing of the foliage, stunted plant growth, and a noticeable reduction in leaf area, which severely impairs the plant's ability to produce grain effectively.

Transmission of the virus occurs primarily through insect vectors, specifically leafhoppers. The spread of the infection is highly dependent on the population density of these vectors, which flourishes under warm and dry climatic conditions. The virus spreads rapidly as these insects feed on infected reservoir plants and subsequently migrate to susceptible crops.

The economic impact of Mastrevirus panici is significant, characterized by yield losses and reduced grain quality. Management strategies focus on an integrated approach: eliminating wild grass hosts, applying insecticides to control leafhopper populations during critical growth stages, and selecting resistant or tolerant varieties to minimize the overall impact of the viral infection.

• Regular scouting for leafhopper activity in fields.
• Timely application of systemic insecticides.
• Removal of grassy weeds from field borders.
• Implementation of crop rotation to break the disease cycle.