Caneberry Disease Update Emphasis on Cane Disease Research. Phillip M. Brannen Plant Pathology Department University of Georgia

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1 Caneberry Disease Update Emphasis on Cane Disease Research Phillip M. Brannen Plant Pathology Department University of Georgia

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3 Cane Diseases Cane blight Spur blight Anthracnose Orange cane blotch Botrytis gray mold Botryosphaeria cane canker Purple blotch

4 Cultural Disease Management Destroy wild brambles within 600 feet of the production area. Consider use of tissue-cultured plants to prevent introduction. Bramble fields should be located in direct sunlight with good air circulation. Improve air circulation when possible, based on site location, pruning, etc. Black plastic may help. Remove and destroy old floricanes immediately after harvest. Do not apply excessive nitrogen. Control weeds within and between rows.

5 Anthracnose (Elsinoe veneta)

6 Anthracnose (Elsinoe veneta) The pathogen attacks black/red raspberries and blackberries. Early infections are most important. The fungus overwinters on old canes. Remove old fruiting canes and infected primocanes and destroy (bury or burn) the tissue. Copper compounds and lime sulfur (delayed dormant only) are of value. Bordeaux mix just before budbreak is recommended in California. Other efficacious chemical fungicides include Abound, Cabrio, Captan, Captevate, Nova, and Pristine.

7 Evaluation of fungicides for control of foliar, cane, and post-harvest diseases of red raspberry, Childers et al., 2002

8 Spur Blight (Didymella applanata)

9 Spur Blight (Didymella applanata) This disease impacts Rubus spp., and it is a major pathogen of red raspberries. Lime sulfur in the late-dormant application window is useful for management. Bloom to preharvest sprays with effective fungicides also reduce infection. Efficacious fungicides include Abound, Captan, Cabrio, Kocide, Pristine, Prophyt, Rally, Switch. Regalia and Sil-Matrix have shown efficacy as well, and these are OMRI approved.

10 Botrytis Gray Mold (Botrytis cinerea) Blackberry and Raspberry problem Blackberry stamen blight causes incomplete/distorted or dried up berries Raspberry bloom and fruit rot problem Cultural Prune for open growth

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13 Purple Blotch (Septocyta ruborum) Bordeaux mix, coppers, Abound, and Pristine have been reported to have activity.

14 Cane Blight (Leptosphaeria coniothyrium)

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19 Cane Blight (Leptosphaeria coniothyrium) This disease impacts all Rubus spp., and it is a major pathogen of blackberries in the Southeast. The pathogen invades wounded tissues and then enters the plant vascular tissue. This disease is especially aggressive in wet years. Younger primocane tissues may be more susceptible to infection. Prune when four days of dry weather are expected. Pinch prune when possible. Destroy old floricanes after harvest. Use chemical fungicides such as Abound, Cabrio, Captevate, Cabrio and Pristine. Quilt Xcel and other fungicides should be reviewed.

20 M. Rahman, West Virginia University, 2013 Fungicides from existing recommendations did not provide good efficacy. Newer fungicides provided better control. Inspire XT (difenoconazole + propiconazole) was best, followed by Quilt Xcel (azoxystrobin + propiconazole) and Quadris Top (azoxystrobin + difenoconazole). In vitro studies indicated fungal resistance may have developed to Pristine and Cabrio. Studies also concluded that early cane removal was very important.

21 Incidence of Cane Blight (2013) * Justin Shealey

22 Incidence of Cane Blight (2014) Justin Shealey

23 Incidence of Cane Blight (2014) Jeremy Taylor

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26 Botryosphaeria cane canker of blackberry

27 Botryosphaeria cane canker of blackberry

28 Patrick Willis and Tim Flanders

29 Phil Harmon, Univ. of Florida

30 Jeremy Taylor, 2013

31 Eddie Beasley and Jeremy Taylor, 2014

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