Managing Vineyard Diseases and Pests Anne DeMarsay and Joseph A. Fiola Maryland Cooperative Extension, Western Region Keedysville, Maryland

Integrated Crop Management Elements of ICM – Plant virus-free vines of disease-resistant varieties – Use good cultural practices  Bio-renovation/perennial weed control  Canopy management  Sanitation  Prevent winter injury to vines – Use biological control of pests where possible – Use chemical controls appropriate to diseases and pests

Bio-renovation Program Start in the spring 2 years before planting vines Start in the spring 2 years before planting vines Objectives Objectives – Increase organic matter in soil to improve fertility (nitrogen content and nutrient-holding capacity) and efficacy of herbicides – Reduce/eliminate residual herbicides – Reduce pathogenic nematodes to protect roots and avoid transmission of viruses – Control perennial weeds

Nematode Testing Nematode testing services available from the Plant Nematology Laboratory, Univ. of MD, College Park Nematode testing services available from the Plant Nematology Laboratory, Univ. of MD, College Park – Forms available from county Extension office or Plant Nematology Laboratory – Instructions for sampling at

Benefits of Canopy Management Good canopy management promotes early ripening AND decreases fungal diseases of fruit Good canopy management promotes early ripening AND decreases fungal diseases of fruit – Allows sunlight to penetrate canopy – Increases air circulation and decreases humidity in canopy – Promotes early drying of leaves and clusters after dew or rain Avoid excessive fertilization, which can make canopy management more difficult Avoid excessive fertilization, which can make canopy management more difficult

Chemical Disease Control Chemical controls are effective for many fungal diseases but not bacterial or viral diseases Chemical controls are effective for many fungal diseases but not bacterial or viral diseases For maximum effectiveness: For maximum effectiveness: – Identify the disease and choose the right product – Follow the label—the label is the law! – Timing is critical

Chemical Disease Control Monitor weather conditions as well as crop phenology and adjust your spray schedule as needed

Chemical Disease Control  Buy the right sprayer and maintain it carefully  Calibrate your sprayer at the beginning of the season  Use the right nozzles and pressure for good canopy penetration  Use adequate spray volume for thorough coverage  Avoid drift

Pathogens of Grapes  Bacteria (crown gall, Pierce’s disease)  Fungi (powdery mildew)  Viruses (leafroll, tomato ringspot decline)  Phytoplasmas (grapevine yellows)

Major Fungal Diseases of Grape  Powdery mildew  Black rot  Phomopsis cane & leaf spot (and fruit rot)  Downy mildew  Botrytis bunch rot

Insect Pest Management Take action against an insect pest only after: Take action against an insect pest only after: – You are certain the insect is present – The insect poses a threat to your crop Action threshold: the pest density that requires control to avoid economic damage Action threshold: the pest density that requires control to avoid economic damage Monitoring methods Monitoring methods – Scouting – Trapping Know the insect’s life cycle and activity in relation to vine phenology Know the insect’s life cycle and activity in relation to vine phenology

Pest Management Spray Program for a Non-Bearing Vineyard TimingTargetMaterials New shoots (start at ½ -1”) Every 10 days (3 sprays) Powdery mildewMancozeb plus a PM fungicide (sulfur, oil, an SI, Quintec, Endura) Pre-bloom to post-bloom Every 10 days (3 sprays) Powdery mildew Downy mildew Mancozeb plus a PM fungicide (sulfur, an SI, Quintec, Endura)

Pest Management Spray Program for a Non-Bearing Vineyard TimingTargetMaterials Cover sprays Every days until frost Powdery mildew Downy mildew Japanese beetle* Captan or a phosphite plus a PM fungicide (sulfur, an SI, Quintec, Endura) *Add Sevin to Jul-early Aug sprays (1 or 2)

References A Pocket Guide for Grape IPM Scouting in the North Central & Eastern U.S. A Pocket Guide for Grape IPM Scouting in the North Central & Eastern U.S. Guidelines for Developing an Effective Fungicide Spray Program for Wine Grapes in Maryland, 2008 (April 2008)— section on non-bearing vineyards Guidelines for Developing an Effective Fungicide Spray Program for Wine Grapes in Maryland, 2008 (April 2008)— section on non-bearing vineyards Home Fruit Production Guide, MD EB 125. Available for $8.00+ S&H from UMD Home & Garden Info Center: Home Fruit Production Guide, MD EB 125. Available for $8.00+ S&H from UMD Home & Garden Info Center: Other University pest management guides (Cornell-Penn State, Virginia Tech)—commercial and home gardening Other University pest management guides (Cornell-Penn State, Virginia Tech)—commercial and home gardening Dr. Wayne Wilcox, Cornell—annual notes on disease control Dr. Wayne Wilcox, Cornell—annual notes on disease control APS Compendium of Grape Diseases APS Compendium of Grape Diseases

Anne DeMarsay, Ph.D. Specialist in Fruit Pathology Maryland Cooperative Extension Central Maryland REC—Upper Marlboro 2005 Largo Road Upper Marlboro, MD Phone: (301) Got a Question?