Ripe Rot (2023)
Ripe rot is a late-season disease caused by multiple species of the fungus Colletotrichum. The disease reduces fruit yield and adversely affects the chemical composition and quality of grapes and wine, leading to undesirable flavors and color.
Sour Rot (2021)
Sour rot of grape is a disorder causing the microbial breakdown of ripening berries rendering them unsuitable for wine production. (PLPATH-FRU-50)
Grape Black Rot (2017)
Black rot is one of the most damaging diseases of grapes in Ohio and other northeastern states. The fungus can infect the leaves, shoots, berries, tendrils, rachises and cluster stems (peduncles) of grapes. (PLPATH-FRU-24)
Downy Mildew of Grape (2008)
Downy mildew is a major disease of grapes throughout the eastern United States. The fungus causes direct yield losses by rotting inflorescences, berries, clusters and shoots. Indirect losses can result from premature defoliation of vines due to foliar infections. (HYG-3013-08)
Powdery Mildew of Grape (2008)
The disease generally is considered less economically important in Ohio than black rot or downy mildew. However, uncontrolled, the disease can be devastating on susceptible varieties under the proper environmental conditions. (HYG-3-18-08)
Botrytis Bunch Rot or Gray Mold of Grape (2008)
Bunch rot can cause serious losses on highly susceptible grape varieties. Although berries of all grape varieties are susceptible to bunch rot, losses generally are greater on tight-clustered varieties. (HYG-3025-08)
Bitter Rot of Grape (2008)
Bitter rot is easily confused with black rot, which is a common disease of grapes throughout Ohio. The ability to distinguish between these two diseases could be vital for growers and especially winemakers. If 10 percent of the berries used to make wine are infected with bitter rot, the wine may be undrinkable. (HYG-3032-08)
Eutypa Dieback of Grape (2008)
Eutypa dieback is the new name for the trunk and arm phase of what was once known as “dead-arm”. The earliest symptom is a canker that generally forms around pruning wounds in older wood of the main trunk. These cankers are usually difficult to see because they are covered with bark. (HYG-3203-08)
Anthracnose of Grape (2008)
Anthracnose reduces the quality and quantity of fruit and weakens the vine. Once the disease is established in a vineyard, it can be very destructive. (HYG-3208-08)
Phomopsis cane and Leaf Spot of Grape
Disease incidence of Phomopsis cane and leaf spot appears to be increasing in many vineyards throughout the Midwest. Crop losses up to 30 percent have been reported in some Ohio vineyards in growing seasons with weather conducive to disease development. (PLPATH-FRU-47)
Bacterial Crown Gall of Fruit Crops (2008)
Crown gall is caused by the bacterium Agrobacterium tumefaciens. This bacterium has the widest host range of any plant pathogen. All fruit crops grown in Ohio are susceptible. The disease is particularly destructive on brambles (raspberries and blackberries) and grapes. (HYG-3301-08)
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