N I C O L E WA R D , U K P L A N T PAT H O LO GY

MANAGING DISEASES IN BACKYARD ORCHARDS

BACKYARD ORCHARDS

• Size• Plant type• Low maintenance• Resistant cultivars

• Dedication • Knowledge • Education• Continuing

education• Publications

DISEASE MANAGEMENT

• Cultivar selection• Canopy management• Sanitation • Air circulation

• Vigor • Scouting• Fungicides

CULTIVAR SELECTION

Disease Resistant Apples Recommended for Kentucky

CultivarResistance to:

Time of Harvest

Apple Scab Cedar Apple Rust Fire Blight Powdery MildewPristine VR S S R mid-JulyRedfree VR VR S S early-AugustDayton VR R MR R mid-AugustLiberty VR R* R R late-AugustSpartan MR R MR R early-SeptemberJonafree VR S S R early-SeptemberPixie Crunch VR - - - early-SeptemberCrimsonCrisp VR MR S S mid-SeptemberPriscilla VR VR* VR R mid-SeptemberSirPrize VR S R R mid-SeptemberEnterprise VR VR* MR R mid-OctoberGoldRush VR S MR S mid-OctoberWinecrisp VR MR VR MR mid-OctoberSundance VR VR VR VR mid-October

VR=very resistant, R=resistant, MR=moderately resistant, S=susceptible, -- = insufficient information

*=although resistant to cedar apple rust, these cultivars are susceptible to cedar quince rust

Information adapted from ID-21

DISEASE-RESISTANT APPLE

• Resistant to major diseases• Scab• Cedar apple rust• Fire blight• Powdery mildew

• Not resistant to• Cork spot• Fly speck/sooty blotch

• Not insect-resistant• Bagging (ENTFACT-218)• Insecticides

SANITATION

Understanding life cycles of fungi (or bacteria) and removing source of spores. • Rake• Remove old fruit• Prune, remove cankers

SPORE POTENTIAL OF FUNGI

Optimal Conditions• Moderate temperatures• Free water• exception powdery mildew

Reproduction• Spores• Spring – sexual spores, initial

infection• Growing season – asexual spores,

repeating stage

• Wind or rain spread

FUNGAL SPORE PRODUCTION

• Asci (sexual spores) formed in fall and overwinter in debris or bark crevices• Conidia (asexual spores)

form throughout the season, numerous

Ascocarp types: apothecia, perithecia, cleistothecia

SEXUAL SPORES

• Ascospores develop in spring• Leaf litter, debris,

cankers• Ascospores germinate

and infect plants in spring (once per season)• Initial infection• Lesions then begin to

produce conidia

INOCULUM POTENTIAL

ASEXUAL SPORES

• Asexual cycle• Inoculum (spores)

increases, repeating stage• Sporulation under

moderate conditions and high humidity

• Some conidia formed in pycnidia (sac)

ASEXUAL SPORES

BACTERIAL CELLS

BACTERIAL DISEASES

SANITATION

Understanding life cycles of fungi (or bacteria) and removing source of spores. • Rake• Remove old fruit• Prune, remove cankers• Do not work in wet

orchards• Sanitize tools

CULTURAL PRACTICES

Air circulation • Optimal conditions• High humidity• Eliminate micro-climates

• Manage canopy by pruning

CULTURAL PRACTICES

Scouting• Know the pathogen• Understand biology• Learn to recognize

Keep learning• Many sources of

information• UK College of Ag website,

fact sheets, publications

• Subscribe to newsletters or blogs

CULTURAL PRACTICES

• Sanitation • Air circulation • Canopy management• Scouting• Vigor

Not just for organicsDisease management is not effective without proper cultural practices.

WHEN ALL ELSE FAILS…OR INTENSELY MANAGED CROPS

FUNGICIDES

• Homeowners purchase • Non-restricted• Small quantities• Cost • Easy to follow instructions• Multi-use• Locally available• Safe (sometimes organic)

LIMITED PRODUCTS

Midwest Spray Guides?

• Captan• Chlorothalonil• Copper• Lime sulfur• Mancozeb• Myclobutanil• Sulfur• Thiophanate-methyl (commercial size)

WHAT’S IN A NAME?

• Trade names change• Trade names can

be confusing• Formulations

What matters is the active ingredient!

ACTIVE INGREDIENTS

Bonide Fungicides:

• Captan 50 WP – captan• Fruit Tree Spray – captan• Copper Dust, Liquid concentrate or RTU – Copper• Fungonil concentrate or RTU – chlorothalonil• Fungonil RTS - propiconazole

Apple & Pearscab x x x x x xfire blight x xpowdery mildew x x x xrust x x x xfruit rots x x

brown rot x x x x x xpeach leaf curl x x x xscab x x x xblack knot of plum x x xcherry leaf spot x x x x x

black rot x x x xpowdery mildew x x x xdowny mildew x x xphomopsis cane & leaf spot x x x

anthracnose x xcane blight x xspur blight x x

leaf spot xfruit rots xpowdery mildew x

mummy berry xphomopsis twig blight x

Brambles

Strawberry

Blueberry

Apple & Pear

Peach, Plum, Cherry

Grape

Propiconazole is labeled for non-bearing fruit trees.

FORMULATIONS

Spectracide Fungicides: myclobutanil

• Immunox Multi-purpose concentrate• Fruit, veggies, nuts, plus ornamentals

• Immunox Lawn Disease Control concentrate hose-end• Immunox Lawn Disease Control granules• Immunox 3-in-1 Insect and Disease + Fertilizer• Ornamental plants only

• Immunox Plus Insect and Disease Control aerosol• Insect and Disease Control concentrate

• No longer available (name change?)

AVAILABILITY

• Ortho – Home Depot, Lowes, Tractor Supply• Spectracide – Lowes• Bonide – Southern States

AVAILABILITY

Immunox Multi-Purpose Fungicide Conc• Only myclobutanil

product labeled for fruit and veggies

• Lowes (local) may not carry (available for store pick-up)

• Know what you need – don’t settle for something else

FUNGICIDE TIPS

• Don’t use commercial products• Don’t borrow fungicides• Restricted-use• Unmarked• Not labeled for fruit

• Insecticides don’t kill fungi• Same active ingredient but different trade name

is often not the same product• Surfactants• Label is the law

• Know your agent• Develop a relationship

ORGANICS

OMRI or Low Impact?

• Copper (surfactant dependent)

• Bonide Liquid Copper Conc or RTU• Ferti-lome Natural Guard Copper Soap• Ortho Elementals Garden Dis Control• Southern Ag Liquid Copper

• Lime sulfur• BSP Lime-Sulfur Solution • Green Cypress Lime Sulfur (Monterey)

• Sulfur • Bonide Sulfur Dust• Safer Garden Fungicide Conc

SPRAY SCHEDULESSIMPLIF IED FOR BACKYARDS

APPLE & PEAR

• Bud to bloom – 4 applications• Scab, powdery mildew, rust

• Petal Fall plus 8 covers• Fruit rots, scab

No one fungicide can be used• Fruit tree spray usually contains captan • not effective against all diseases

• Resistant cultivars affect priorities

APPLE DISEASES

PEACH, PLUM, & CHERRY

• Dormant• Peach leaf curl, black knot of plum

• Bloom plus covers – 8 applications until 3-4 wks before harvest• Scab, brown rot, black knot of plum, cherry leaf spot

Just one fungicide required• Fruit tree spray usually contains captan • Usually effective against all diseases

PEACH DISEASES

GRAPE

• Pre-bloom• Black rot, phomopsis, mildews• Myclobutanil – black rot, powdery mildew• Captan / Mancozeb – black rot, downy mildew, phomopsis

• Post-bloom plus 2 covers• Black rot, powdery mildew, downy mildew

• 3rd & 4th cover• Downy and powdery

Multiple fungicides required

GRAPE DISEASES

BRAMBLES

• Bud break – if disease has been a problem• Anthracnose, cane blight, spur blight

BLACKBERRY DISEASES

STRAWBERRY

• Bloom – if weather is rainy• Fruit rots, leaf spots

• After harvest – if required• Leaf spots

STRAWBERRY DISEASES

BLUEBERRY

• Green tip to bloom – 3 applications• Stem cankers and mummy berry if history of disease

BLUEBERRY DISEASES

SUMMARY

• Some fruit require intense management• Preventative sprays

• Keep learning• Diseases identification• Cultural practices• Fungicide labels• Efficacy of fungicides

• Know your agent• Ask questions• Field visits• Educational materials• Diagnostics

Nicole Ward, Extension Specialist

Department of Plant Pathologywww.ca.uky.edu/agcollege/plantpathology/people/ward.htm

nicole.ward@uky.edu

859-218-0720 office859-797-3333 mobile/text

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