Virus – Blueberry Field Guide

Virus Not In BC

Blueberry Leaf Mottle

(Blueberry leaf mottle virus – BLMV)
Damage: Leaves are mottled and may be malformed or strap-like. The top of bushes die back with weak regrowth occurring only at the crown.
Disease: BLMV is spread by pollen and carried by bees. It is present in Michigan.
blmv

Blueberry Red Ringspot

(Blueberry red ringspot virus – BRRV)
Damage: Circular red rings or blotches, 4-6 mm in diameter, develop on one-year-old and older stems. Older leaves develop reddish brown circular spots, 3-5 mm in diameter, in mid to late summer.
Disease: The disease is caused by BRRV and it is not known how it spreads. It is present at low incidence in Oregon and the Eastern US. ‘Bluecrop’ is resistant to this disease.
brrv

Blueberry Shoestring

(Blueberry shoestring virus – BSSV)
Damage: New and one-year-old stems show red streaks, 3-20 mm long, more on the side of the stem exposed to the sun. Leaves are elongated and strap-like (shoestring appearance), and may be reddish in colour. Blossoms have reddish streaks. Berries are reddish purple instead of blue. Yield is reduced.
Disease: BSSV is spread by the blueberry aphid, Illinoia pepperii, which is not present in BC. The virus has a latency period of 4 years before infected bushes show symptoms.
bssv

Blueberry Stunt

Damage: Bushes are severely stunted and bushy. Leaves may be spoon-shaped or cupped downward with chlorotic margins and chlorosis between the veins. Chlorotic areas turn bright red in late summer. Yield is reduced.
Disease: This disease is caused by a phytoplasma and is spread by leafhoppers. It is present in Eastern Canada and the Eastern US.
blueberry-stunt

Necrotic Ringspot

(Tobacco ringspot virus – TRSV)
Damage: Symptoms vary among cultivars. Leaves may be small, misshapen, crinkled and have small necrotic spots, 2-5 mm in diameter. Young twigs may have small brown necrotic patches. Yield is reduced. Symptoms are similar to those of ToRSV.
Disease: TRSV is spread by dagger nematodes (Xiphinema spp.) from infected to healthy roots in the soil. It causes plant decline in Oregon and the Eastern US.

Tomato Ringspot

(Tomato ringspot virus – ToRSV)
Damage: Leaves are cupped and misshapen or elongated and have pale yellow or brown circular spots of 2-5 mm in diameter. Stems may have brown, circular spots of 2-5 mm in diameter. Some shoots may appear normal, others may have misshapen leaves. An infected bush can be completely defoliated.
Disease: ToRSV is spread by dagger nematodes (Xiphinema spp.) from infected to healthy roots in the soil. The virus spreads slowly, causing plant decline in expanding circular patches in the field. It is present in Washington, Oregon and Michigan. It has been detected in BC on raspberries but not on blueberries.

Premature Fruit Drop

Damage: Flowers and leaves have red streaking during bloom. Berries begin to develop, reach 3-5 mm in size and then prematurely turn blue and drop. Infected bushes stand taller than neighbouring bushes as they have no fruit. Symptoms have only been noted on Bluecrop.
Disease: The causal agent of this disease is not well understood.

Premature Fruit DropRobert Martin, USDA-ARS

Premature Fruit Drop Leaf ReddeningRobert Martin, USDA-ARS

Premature Fruit DropRobert Martin, USDA-ARS

4-premature-fruit-drop-unhealthy-vs-healthy-bush-2

Unhealthy vs Healthy BushRobert Martin, USDA-ARS

Premature Fruit Drop Height DifferencesRobert Martin, USDA-ARS

Blueberry Shock Virus (BIShV)

Blueberry Shock

Blueberry shock virus BIShV
Damage: Flowers and/or leaves blight and die, while stems remain green. Yield is reduced. Symptoms are nearly identical to Blueberry scorch, but blighting may occur slightly earlier. Symptoms appear at blossom and remain visible from spring to mid-summer.
Disease: BIShV is spread by pollen. Infected bushes will recover in 1-4 years, but will remain infected with the virus. This virus will slowly spread through an entire field.

Blueberry Shock VirusCarolyn Teasdale, ES Cropconsult

Blueberry Shock VirusCarolyn Teasdale, ES Cropconsult

Blueberry Shock VirusCarolyn Teasdale, ES Cropconsult

Blueberry Shock Virus

Blueberry Scorch Virus (BIScV)

Blueberry Scorch

Blueberry scorch virus BIScV
Damage: Flowers and/or leaves blight and die, while stems remain green. Yield is reduced. Some varieties, like Bluecrop, may not show blighting but leaves may turn slightly yellow and yields will be reduced. Symptoms appear at blossom and remain visible from spring to mid-summer.
Disease: BIScV is spread by aphids and infected propagating plant materials. The virus can spread rapidly in the field. Bushes infected with this disease will never recover.