Blueberry shock virus

Blueberry shock virus (BlShV) is a serious viral disease caused by a member of the Ilarvirus genus. It primarily impacts highbush blueberry plantations, but it also has the potential to infect cranberry, which can serve as a reservoir for the pathogen in mixed agricultural environments.

The characteristic signs of the disease appear abruptly during the spring flowering season. Infected plants show sudden wilting, followed by the browning and necrosis of flowers and young foliage. The appearance of the plant often mimics severe frost damage, which is why the condition is commonly referred to as a "shock" to the plant system.

Transmission occurs primarily through the spread of infected pollen. Pollinating insects, such as honeybees and bumblebees, carry the virus while moving from flower to flower. Since the virus is systemic, once a plant is infected through its blossoms, the virus spreads to the rest of the plant's tissues, establishing a permanent infection.

The economic impact of this disease is significant, primarily due to immediate crop loss. In the first year of infection, fruit production is typically halted. Although infected plants may eventually recover and resume normal growth after several years, they remain latent carriers of the virus and continue to pose a threat to surrounding healthy plants.

Management of the disease relies heavily on exclusion and sanitation, as there is no chemical cure. Producers should prioritize sourcing planting material from certified virus-free nurseries. If a plant exhibits symptoms, it must be rogued out and destroyed immediately to prevent the cycle of pollen-borne transmission to the rest of the field.