Aside from the heat wave this year affecting blueberry crops, there is also a new blueberry scorch virus. The original scorch virus causes damage to a plant’s leaves, shoot, and fruit production; it is also latent for 2 years before these systems develop meaning farmers are not able to treat the crops right away. During bloom is when BlSV symptoms can be seen most clearly. In extreme circumstances, after an early bloom, blooms and foliage swiftly rot and dry up.
Depending on the blueberry variety, blighted flowers may stay on the shrub throughout the summer and into the next year. Along their borders, leaves occasionally turn yellow. Plants that exhibit these signs typically deteriorate and wither over time. Other, more subtle symptoms include a lack of flowers or a “twiggy” look, as well as red line patterns on leaves in the fall and leaf mottling. Even though the scorch virus has been around since the 2000’s this year has caused a significant loss to blueberry crops in the Fraser Valley. It seems that about 18 percent of visibly diseased plants are testing negative for the scorch virus and the blueberry shock virus for an unknown reason in 2020 meaning this rapidly spreading disease might be something else entirely.
Researchers are working tirelessly to try and diagnose and prevent this disease from spreading further. So far it has been determined that there are two new strains of a blueberry virus and one new shock virus.
https://thegrower.org/news/researchers-look-source-disease-afflicting-bc-blueberry-plants