Blueberry Shoestring Virus

The leaves of a healthy blueberry plant are green. The same cannot be said of bushes infected with the blueberry shoestring virus (BBSSV). This disease is common to the upper and northeastern Midwest, but it is also found in Oregon, North Carolina, Washington, and New Brunswick, Canada, and is expected to spread.

Symptoms of blueberry shoestring virus (Dr. Mark Longstroth, LSU) CC BY-SA 3.0

Both lowbush (Vaccinium angustifolium) and highbush blueberries (V. corymbosum) are susceptible to the blueberry shoestring virus.

Blueberry shoestring virus symptoms

The leaves and stems of a plant infected with the blueberry shoestring virus are red and deformed. Young stems may show red streaking and leaves become significantly thinner than normal, hence the name. Ultimately, leaves become crescent-shaped and fruit production is all but eliminated.

Other symptoms of blueberry shoestring virus include an oak-leaf pattern of red surrounding leaf veins, flowers of infected plants tend to be pinkish-purple, rather than white, and discolored berries do not turn blue.

Flowers infected with blueberry shoestring virus (Dr. Mark Longstroth, LSU) CC BY-SA 3.0

Blueberry shoestring virus lifecycle

The blueberry shoestring virus may take up to 4 years to start expressing itself. This allows the disease to spread silently as aphid vectors move from plant to plant, feeding and infecting. Since this disease is spread by aphids, monitoring for and controlling these pests is the best way to keep your blueberry plants healthy.

Infected aphids spread the disease as they feed. They also lay eggs at the base of blueberry buds where they overwinter. As spring temperatures begin to rise, the eggs hatch, and a new generation of infected aphids continues the problem. These eggs tend to hatch when temperatures reach 38°F, so that’s when you need to start treating blueberry plants for aphids.

Blueberry shoestring virus management

Natural predators, such as ladybugs, especially seven-spotted lady beetles, and parasitic wasps provide significant protection against aphid-borne diseases, so avoid using broad-spectrum pesticides. Also, starting with certified pest- and disease-free plants is always a good idea. Infected plants should be bagged and removed immediately. There is no cure for the blueberry shoestring virus.

To protect your plants against the blueberry shoestring virus, do your best to keep aphids under control.