Peach rosette mosaic nepovirus

Peach rosette mosaic nepovirus (PRMV) is a serious viral disease caused by a member of the Nepovirus genus. This pathogen is of significant economic concern for fruit growers, as it leads to progressive decline of stone fruit trees and reduces the quality and quantity of the harvest.

The primary hosts of this virus include peach, nectarine, and sweet cherry trees, as well as grapevines. Various weed species within the orchard can also harbor the virus, acting as persistent reservoirs that complicate efforts to eradicate the pathogen from infected fields.

Infected plants typically show severe symptoms including shortened internodes, which give the foliage a bunched or "rosette" appearance. Leaves often display mottling, chlorotic rings, or line patterns. Fruit development is frequently impaired, resulting in small, misshapen fruit that lacks market value, ultimately shortening the productive life of the tree.

The virus is primarily transmitted through the soil by dagger nematodes (Xiphinema species), which feed on the root systems of host plants. Transmission can also occur via infected propagation material, such as scion wood or rootstocks, as well as through mechanical transmission during pruning operations if tools are not properly sanitized.

Management of PRMV focuses on prevention since curative treatments for infected trees do not exist. Growers should prioritize sourcing certified virus-free nursery stock, implementing strict nematode control programs, and maintaining weed-free orchard floors. Disinfecting pruning tools between trees is a mandatory practice to prevent mechanical spread within the planting.