Latin name: (no Latin name)
Reason for Concern:
1) Causes economic damage in B.C. and northern Washington.
2) Can reduce growth and cause crumbly fruit resulting in severe quality and yield loss.
3) The fruit from infected plants often will not make IQF grade and is sold as lower value produce.
4) If a field is infected with RBDV, it needs to be replanted on a 5 or 6 year cycle (compared to 15-20 years for healthy plants) because the yield and quality losses are too great for the grower to maintain any profit margin.
Most commercially recommended varieties do not show any leaf symptoms. Leaf tissue lab testing is the only way to confirm presence of RBDV. Crumbly fruit is the most common symptom, but other factors can cause crumbly fruit. Infected plants are neither bushy nor dwarfed, but stunting and shorter canes occur in some varieties. Some varieties, such as Autumn Bliss, may also show leaf yellowing.
A seed and pollen-born virus that spreads during bloom, honeybees move the infected pollen from plant to plant. A pollinated blackberry flower infects the embryo and the mother plant. The exact mechanism by which RBDV infects the seed and mother plant is unknown. Temperature, humidity levels, insect vectors and spread from native vegetation can affect transmission. Studies have already shown that native Rubus species such as thimbleberry (R. parviflorus) can be naturally infected with RBDV.