Submitted to: The Blueberry Bulletin
Publication Type: Experiment Station
Publication Acceptance Date: 5/8/2018
Publication Date: 5/10/2018
Citation: Polashock, J.J. 2018. Scouting, prevention and recommendations for blueberry viruses [abstract]. The Blueberry Bulletin. 34(2):2.
Technical Abstract: It is important to remember that blueberry viruses are systemic and virus infections in plants cannot be cured. New fields should be planted with clean virus-tested planting stock. Since viruses can move in from the wild, fields should be monitored for appearance virus symptoms. To help prevent spread, the vectors must be controlled. Sucking insects, such as aphids, can be vectors. Nematodes can also vector viruses. Symptomatic plants should be confirmed to be infected since other problems, such as insect damage, herbicide damage, and abiotic events, can mimic symptoms of virus infection. It is important to remember that symptoms can vary among blueberry cultivars. Even though symptoms might appear mild in the infected cultivar, symptom expression in other cultivars might be severe. Symptom expression can also vary from year to year. Thus, infected plants should be removed regardless of symptom severity at the time of discovery. When removing infected plants, the cuttings or rogued bushes should not be left near healthy plants. Several virus diseases are known to be present in New Jersey. These include Red Ringspot, Scorch, Shoestring and Necrotic Ringspot. Briefly, symptoms are as follows. Red Ringspot- Red rings or blotches on leaves and sometimes stems, red rings on ripening fruit that disappear when the fruit are fully ripe. Vector is unknown. Scorch- Blossom blight (giving a ‘scorched’ appearance), shoot dieback, leaf chlorosis, red line patterns on leaves can appear in late summer. Vectored by aphids. Shoestring- Red strap-shaped leaves, pink streaks on stems and flowers, red ‘oakleaf’ pattern on leaves, reddish purple fruit. Vectored by aphids. Necrotic Ringspot- Crinkled or misshapen leaves, necrotic spots on leaves that may fall out, rosette leaves on some cultivars. Bushes decline and die. Vectored by nematodes. Several guides available that show photos of symptoms in virus infected plants. When using any guide, note that all viruses listed may not be found in all areas However, it is important to be vigilant since ‘new’ viruses can move in from many sources including planting stock purchased from out of state. Spread can often be prevented if steps are quickly taken to eradicate new introductions.