Plant reoviruses

Plant reoviruses (Reovirales) are a significant group of phytopathogenic viruses characterized by a double-stranded RNA genome. These viruses cause severe systemic diseases in various crops, leading to substantial economic losses in agricultural sectors worldwide, particularly in tropical and temperate regions where their vectors thrive.

These pathogens primarily target monocotyledonous plants, with rice, maize, and sugarcane being the most susceptible hosts. The virus colonizes the plant's phloem, effectively disrupting the transport of nutrients and photosynthesis products, which leads to the collapse of the plant's structural and reproductive integrity.

The most common symptoms include stunted growth (dwarfing), chlorotic stripes, leaf gall formation, and intense yellowing or reddening of leaves. In affected rice crops, the plants often exhibit excessive tillering, and the formation of the panicle is either incomplete or entirely suppressed, resulting in poor grain quality.

Reoviruses are exclusively transmitted by insect vectors, primarily leafhoppers and planthoppers, in a persistent-propagative manner. The virus not only survives but multiplies within the insect's body, ensuring that once a vector becomes infective, it remains a threat to crop health for the remainder of its lifespan.

Effective management requires an integrated pest management (IPM) strategy focused on minimizing vector populations and removing alternative weed hosts. Current preventative measures include the cultivation of resistant crop varieties, the use of virus-free seeds, and the application of systemic insecticides at critical stages of plant development to prevent early infection.