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

Managing Vineyard Managing Vineyard Diseases and PestsDiseases and Pests

Anne DeMarsay and Joseph A. Anne DeMarsay and Joseph A. FiolaFiola

Maryland Cooperative Extension, Maryland Cooperative Extension, Western RegionWestern Region

Keedysville, MarylandKeedysville, Maryland

IIntegrated ntegrated CCrop rop MManagementanagement Elements of ICMElements of ICM

– Plant virus-free vines of disease-Plant virus-free vines of disease-resistant varietiesresistant varieties

– Use good cultural practicesUse good cultural practices Bio-renovation/perennial weed controlBio-renovation/perennial weed control Canopy managementCanopy management SanitationSanitation Prevent winter injury to vinesPrevent winter injury to vines

– Use biological control of pests Use biological control of pests where possiblewhere possible

– Use chemical controls appropriate Use chemical controls appropriate to diseases and peststo diseases and pests

Bio-renovation ProgramBio-renovation Program

Start in the spring Start in the spring 2 years2 years before planting before planting vinesvines

ObjectivesObjectives– Increase organic matterIncrease organic matter in soil to improve in soil to improve

fertility (nitrogen content and nutrient-holding fertility (nitrogen content and nutrient-holding capacity) and efficacy of herbicidescapacity) and efficacy of herbicides

– Reduce/eliminate residual herbicidesReduce/eliminate residual herbicides– Reduce pathogenic nematodes Reduce pathogenic nematodes to protect roots to protect roots

and avoid transmission of virusesand avoid transmission of viruses– Control perennial weedsControl perennial weeds

Nematode TestingNematode Testing Nematode testingNematode testing services available from services available from

the Plant Nematology Laboratory, Univ. of the Plant Nematology Laboratory, Univ. of MD, College ParkMD, College Park– Forms available from county Extension office Forms available from county Extension office

or Plant Nematology Laboratory or Plant Nematology Laboratory – Instructions for sampling at Instructions for sampling at

http://nematology.umd.eduhttp://nematology.umd.edu

Plant Pathogenic NematodesPlant Pathogenic Nematodes

© CABI Bioscience, Egham, UK, 2004

Sourced from www.cabi-bioscience.org

Stylet on root-feeding nematode

Courtesy U. Wyss, used by permission of the Society of NematologistsSourced from http://www.apsnet.org

Dagger nematode feeding on a fig root

Nematode DamageNematode Damage

LeftLeft: grapevine roots : grapevine roots damaged by lesion damaged by lesion nematodesnematodes

RightRight: a healthy root : a healthy root systemsystem

©Howard Ferris, 1999. Used by permission of author. Sourced from: http://plpnemweb.ucdavis.edu/Nemaplex

Benefits of Canopy Benefits of Canopy ManagementManagement

Good canopy management promotes early Good canopy management promotes early ripening ripening ANDAND decreases fungal diseases of fruit decreases fungal diseases of fruit

– Allows sunlight to penetrate canopyAllows sunlight to penetrate canopy– Increases air circulation and decreases humidity in Increases air circulation and decreases humidity in

canopycanopy– Promotes early drying of leaves and clusters after Promotes early drying of leaves and clusters after

dew or raindew or rain

Avoid excessive fertilizationAvoid excessive fertilization, which can make , which can make canopy management more difficultcanopy management more difficult

Cultural Practices: Canopy Management

Light exposureAir exposurePesticide exposure

Cultural Practices: Weed Control

Weeds harbor insects and may be hosts for diseases

Chemical Disease ControlChemical Disease Control

Chemical controls are effective for many Chemical controls are effective for many fungal diseases but not bacterial or viral fungal diseases but not bacterial or viral diseasesdiseases

For maximum effectiveness:For maximum effectiveness:– Identify the disease and choose the right Identify the disease and choose the right

productproduct– Follow the label—the label is the law!Follow the label—the label is the law!– Timing is criticalTiming 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

Powdery Mildew

Active (sporulating) leaf infections

Powdery Mildew

Fruit cluster infection

Older leaf lesions

Black Rot

Fruiting bodies in leaf lesion

Black Rot

Photos: Turner B. Sutton, by permission

Black Rot

Photos: Turner B. Sutton, by permission

Lesions on shoot and rachis

Lesions on young leaf (left) and older leaf (right)

Photos: Midwest Grape Production Guide, Ohio State University Extension Bulletin 919, Columbus, Ohio, 2005, p. 71.

Phomopsis Cane and Leaf Spot

Phomopsis Cane and Leaf Spot

Photos: Turner B. Sutton, by permission

Downy Mildew

Young “oil spot” lesions on upper leaf surfaces

Photo: J. Pscheidt, by permission. From http://plant-disease.ippc.orst.edu/

Downy Mildew

“Cottony” sporulation on underside of leaf

Downy Mildew

Sporulation on fruit clusters destroyed by DM

Botrytis Bunch Rot

Sporulation on leaf lesion

Shoot infection

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Botrytis Bunch Rot

Photos: (L) Turner B. Sutton, by permission; (R) APS Small Fruit Digital Image Collection

Insect Pest ManagementInsect Pest Management Take action against an insect pest only after:Take action against an insect pest only after:

– You are certain the insect is presentYou are certain the insect is present– The insect poses a threat to your crop The insect poses a threat to your crop

Action thresholdAction threshold: the pest density that requires : the pest density that requires control to avoid economic damagecontrol to avoid economic damage

Monitoring methodsMonitoring methods– ScoutingScouting– TrappingTrapping

Know the insect’s life cycle and activity inKnow the insect’s life cycle and activity inrelation to vine phenologyrelation to vine phenology

Biological Control of Pests

Protect beneficial insects that prey on plant pests

Insect Pest Monitoring Methods

Scouting for insects and damage

Insect Pest Monitoring Methods

Pheromone traps

Insect Pest Monitoring Methods

Colored sticky traps

Monitor Activity for Effective Control

Understand the Insect’s Life Cycle

Grape root borer larva

Understand the Insect’s Life Cycle

Grape root borer larvae feed for two years before pupating

Understand the Insect’s Life Cycle

. . . And are best controlled as adult moths

Understand the Insect’s Life Cycle

Insect Control Options

Mating disruption with pheromones

Mass trapping, with or without pheromones

Parasitism/predation by natural enemies

Insecticides

Insect Pests on Foliage

Leafhoppers cause

“hopper burn”

Insect Pests on Foliage

Japanese beetles skeletonize leaves

Insect Pests on Foliage

Grape phylloxera forms galls on leaves and susceptible rootstocks

Pest Management Spray Programfor a Non-Bearing Vineyard

Timing Target Materials

New shoots(start at ½ -1”)

Every 10 days(3 sprays)

Powdery mildew Mancozeb plus a PM fungicide (sulfur, oil, an SI, Quintec, Endura)

Pre-bloom to post-bloom

Every 10 days(3 sprays)

Powdery mildewDowny mildew

Mancozeb plus a PM fungicide (sulfur, an SI, Quintec, Endura)

Pest Management Spray Programfor a Non-Bearing Vineyard

Timing Target Materials

Cover sprays

Every 14-21days 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)

ReferencesReferences A Pocket Guide for Grape IPM Scouting in the North Central & A Pocket Guide for Grape IPM Scouting in the North Central &

Eastern U.S.Eastern U.S.

Guidelines for Developing an Effective Fungicide Spray Guidelines for Developing an Effective Fungicide Spray Program for Wine Grapes in Maryland, 2008 Program for Wine Grapes in Maryland, 2008 (April 2008)—(April 2008)—section on non-bearing vineyardssection on non-bearing vineyards

Home Fruit Production Guide, MD EB 125. Home Fruit Production Guide, MD EB 125. Available for Available for $8.00+ S&H from UMD Home & Garden Info Center: $8.00+ S&H from UMD Home & Garden Info Center: www.hgic.umd.eduwww.hgic.umd.edu

Other University pest management guides (Cornell-Penn Other University pest management guides (Cornell-Penn State, Virginia Tech)—commercial and home gardeningState, Virginia Tech)—commercial and home gardening

Dr. Wayne Wilcox, Cornell—annual notes on disease controlDr. Wayne Wilcox, Cornell—annual notes on disease control

APS APS Compendium of Grape DiseasesCompendium of Grape Diseases

Anne DeMarsay, Ph.D.Specialist in Fruit PathologyMaryland Cooperative ExtensionCentral Maryland REC—Upper Marlboro 2005 Largo RoadUpper Marlboro, MD 20774-8508Phone: (301) 627-8440

Email: [email protected]

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