Peach mosaic

Peach mosaic is a viral disease caused by the Peach mosaic virus (PmV). It is considered one of the most serious systemic diseases affecting stone fruits, as it can cause significant yield losses and long-term decline in tree health. The virus disrupts normal hormonal balances and nutrient transport, leading to a general weakening of the host tree.

The disease primarily affects species within the Prunus genus. In addition to peach, common hosts include apricot (Prunus armeniaca) and almond (Prunus dulcis). Because the virus can remain latent in some cultivars while showing severe symptoms in others, it is often difficult to detect the infection until it has already spread throughout the orchard.

Clinical signs of infection are most visible during the spring flush. Key symptoms include:

• Yellow mosaic patterns, spots, or mottling on the foliage.
• Leaf deformation, such as crinkling, puckering, or narrowing of blades.
• Shortening of internodes, resulting in a stunted or rosetted appearance of shoots.
• Fruit abnormalities, including surface pitting, bumps, and irregular ripening patterns.

The transmission of Peach mosaic occurs mainly through the movement of eriophyid mites (such as Eriophyes insidiosus), which act as natural vectors. These mites feed on infected trees and then migrate to healthy ones. Additionally, human activities play a major role in the spread, as grafting with infected scions or rootstocks is a common way the virus enters new nursery and orchard environments.

Management of Peach mosaic requires a strict exclusion strategy since there is no chemical cure for the virus. Growers should prioritize sourcing disease-free, certified stock from reputable nurseries. Periodic scouting for symptoms and mite populations is essential. Any tree suspected of being infected must be promptly removed and destroyed to prevent the vectors from spreading the virus to the remaining healthy trees.