Raspberry ringspot

Raspberry ringspot virus (RRSV) is a significant plant pathogen belonging to the Nepovirus genus. This virus causes systemic infections in a wide range of fruit and vegetable crops, with raspberries, strawberries, and grapevines being particularly susceptible to its detrimental effects.

The biology of RRSV involves specific soil-borne nematodes, primarily Longidorus and Xiphinema species, which act as vectors. The virus particles attach to the nematode's esophagus and are transmitted when the vector feeds on the roots of healthy plants. Once introduced into the root system, the virus spreads through the plant's vascular tissue, leading to a permanent systemic infection.

The symptoms are highly indicative of viral stress: infected leaves develop chlorotic rings, mosaic patterns, and significant distortion. Plants often show stunted growth, reduced vigor, and poor fruit quality. In severe cases, the entire plant may collapse, leading to substantial yield losses in commercial berry production systems.

Development and spread of the virus are favored by moist soil conditions, which facilitate the mobility and feeding activity of the vector nematodes. Furthermore, the virus can persist in perennial weeds, allowing it to survive for long periods in the soil even without the primary host crop. This makes crop rotation and weed management essential components of any control strategy.

Control and prevention are primarily based on the following practices:

• Sourcing healthy, virus-tested planting material from reputable nurseries.
• Rigorous soil testing to detect nematode populations before planting.
• Implementing soil disinfection or nematicide treatments to reduce vector density.
• Prompt roguing and destruction of symptomatic plants to limit spread.
• Maintaining a clean environment by eliminating weed reservoirs.

Effective management requires a long-term approach, focusing on exclusion and vector control. Because there is no chemical cure for systemic viral infections in plants, preventing the introduction of the virus remains the only economically viable strategy for commercial producers.