Grape IPM in the Northeast
Trace Bloom (5 percent Bloom)
IPM practice to be implemented
- continue disease management protocols
- weather parameters of temperature, precipitation, leaf wetness, and relative humidity
Inoculum available for infection
- Botrytis bunch rot 211k pdf file, and see discussion below.
- powdery mildew 490k pdf file
- black rot 548k pdf file
- Phomopsis Cane and Leaf Spot 277k pdf file
- downy mildew 300k pdf file
Botrytis is a fungus that causes a bunch rot of clusters and a blight of blossoms, leaves, and shoots. The bunch rot phase of the disease can cause severe economic losses, particularly on tight-clustered French hybrid and Vitis vinifera cultivars. Botrytis can colonize dead floral parts within clusters and infect the berries, rachises, or pedicels. A bloom fungicide application is generally not necessary in most years. If the bloom period is warm (average day and night temperatures >60°F) and wet, a fungicide application for Botrytis may be warranted.