Potato leafroll virus

Potato leafroll virus (PLRV) is a major plant pathogen within the genus Polerovirus, family Solemoviridae. This virus is one of the most economically significant viral threats to potato production worldwide, known to cause systemic infections that severely restrict plant growth and reduce tuber quality.

The virus primarily affects Solanaceous crops, with potatoes being the most susceptible host. Infection is characterized by the upward rolling of leaflets, particularly on the upper leaves, which often become leathery and chlorotic. In susceptible varieties, the virus may also induce net necrosis in the tubers, which significantly reduces their commercial value and marketability.

The biological transmission of PLRV is carried out in a persistent, circulative manner by aphid species, most notably the green peach aphid (Myzus persicae). Once an aphid ingests the virus from an infected plant, the virus moves through the aphid's gut into the hemolymph and eventually into the salivary glands, allowing the insect to transmit the disease for the remainder of its life cycle.

Environmental conditions that favor aphid population explosions are directly linked to the rapid spread of the virus within and between potato fields. The virus is non-mechanically transmitted in the field but is readily spread through the planting of infected tubers. This accumulation of the virus in seed stocks is the primary driver of potato degeneration.

Integrated management is essential for controlling PLRV, as there are no chemical treatments to cure infected plants. The most effective strategies include:

• Utilizing certified virus-free seed tubers for planting.
• Implementing strict aphid control programs using systemic insecticides.
• Employing spatial isolation of seed production fields from commercial crops.
• Early detection and roguing of infected potato plants.

Losses caused by PLRV are severe, often reaching up to 80% under heavy pressure. By combining resistant cultivars, rigorous monitoring of aphid populations, and strict adherence to certification standards, farmers can successfully mitigate the damage caused by this persistent viral disease.