Managing Stone FruitDiseases and Updates on

the Spray Guides

Mohammad BabadoostUniversity of Illinoisbabadoos@illinois.edu3-4 February 2015

Stone Fruit Diseases_________________________________

Bacterial spot Brown rot Updates in the spray guides

Babadoost

Updates in the Spray Guides__________________________________

New fungicide registrations Important notes

Babadoost

New Fungicides/Bactericides for Fruit Crops, 2015Common Name Trade Name Crop Diseases

Kasugamycinhydrochloride

[FRAC Code: 24]

Kasumin 2L Apple Fire blight

Pear Fire blight

Fluazinam

[FRAC Code: 29]

Omega500F

Apple Scab, sooty blotch, flyspeck,bitter rot, black rot, white rot,rust, Alternaria blotch (alsomites)

Dodine

[FRAC Code: M]

Syllit FL Apple Scab, powdery mildew, rust

Fluopyram

[FRAC Code: 7]

LunaPrivilege4.16FL

Apple Scab, powdery mildew, sootyblotch, flyspeck

Cherry(sweet &tart)

Brown rot, shot hole,powdery mildew, scab,cherry leaf spot, Botrytis fruitrot

Strawberry Powdery mildew

New Fungicides/Bactericides for Fruit Crops, 2015Common Name Trade Name Crop Diseases

Azoxystrobin +Difenoconazole

[FRAC Code:11+3]

Quadris Top1.67SC

Stone fruit(apricots,cherries,nectarines,peaches, plums,prunes)

Alternaria spot,anthracnose, brown rot(blossom blight andfruit rot), leaf rust,powdery mildew, scab,shot hole

Blueberry,Strawberry, andother berries (seethe label)

Anthracnose, leaf rust,leaf spot, powderymildew

Grape Several diseases

Quadris Top is phytotoxic to some apple cultivars (e.g.,McIntosh). Be extremely careful of the drift of Quadris Toponto apples. Do not use the same sprayer for apples andstone fruit, if you are using Quadris Top .

Babadoost

New Fungicides/Bactericides for Fruit Crops, 2015Common Name Trade Name Crop Diseases

Azoxystrobin +Propiconazole

[FRAC Code:11+3]

Quilt Xcel2.2SC

Stone fruit(apricots,cherries,nectarines,peaches,plums, prunes)

Alternaria spot,anthracnose, brown rot(blossom blight and fruitrot), cherry leaf spot, leafrust, powdery mildew,scab, shot hole

Blackberry,raspberry, andother berries(see the label)

Anthracnose,Botryosphaeria canker,rosette (Cercospora spot),leaf and cane spot,powdery mildew, rust

Strawberry Anthracnose, leaf rust, leafspot, powdery mildew

Quadris Top is phytotoxic to some apple cultivars (e.g.,McIntosh). Be extremely careful of the drift of Quadris Toponto apples. Do not use the same sprayer for apples andstone fruit, if you are using Quadris Top .

Babadoost

Important Notes______________________________________

Use streptomycin (e.g., Agri-Mycin17). If the pathogen is resistant tostreptomycin, then use Kasumin 2L(kasugamycin)

Azoxystrobin (Abound, Quadris,Quadris Top, Quilt Xcel, …) arephytotoxic on some apple cultivar.

Babadoost

Bacterial Spot of StoneFruit Diseases

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Babadoost

Lesions on upperleaf surface

Lesions on lowerleaf surface

Bacterial spot of peach: leaf symptoms

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Bacterial spot of peach: leaf chlorosis

Infected Fruit

Infected Fruit Infected Fruits at Harvest

Bacterial Spot: Fruit Symptoms

26 Jun 1 Jul 8 Jul 15 Jul

24 Jul 30 Jul 5 Aug

Bacterial spot: symptom developmenton an individual peach fruit

NC State University

Bacterial Spot of Stone Fruit______________________________________

Pathogen:Xanthomonas arboricola pv. pruni

Pathogen survival: in buds, cankers,cracks in barks, and leaf scars

Disease development is favored by:moist and warm conditions. Higherdisease severity in sandy soil.

Management of Bacterial Spot_______________________________________

Control of the disease: challenging

Disease resistance: resistance ofpeaches and nectarines varies insusceptibility/resistance (seeattached handout)

Nutrient stress: higher disease severity

Sandy soil: prevent sand blowing

Chemical use: copper, oxytentracycline

THEY CAN:- Prevent/delay the start of the epidemic- Slow the progress of the epidemic

THEY CANNOT:- Stop the epidemic as long as conditions

remain favorable for infection anddisease development

- Eradicate/cure infections

What Coppers Can and Cannot Do

Early bud-break Pink-bud Blossoms opening

Applications of Copper Sprays2.0-2.5 lb Cu/A 1.5-2.0 lb Cu/A 1.0 lb Cu/A

Applications of Copper Sprays

Petal-fall Shuck-split/Shuck-off

Copper phytotoxicity may begin to occur

0.50 lb Cu/A 0.10-0.25 lb Cu/A (+ Mycoshield)

Copper (Cu) in the Compounds______________________________________

Kocide: Cu(OH)2,64 Cu/98 Cu (OH)2For 2 lb Cu, 3 lb Kocide needed

Copper sulfate: CuSO4,64 Cu/160 CuSO4For 2 lb Cu, 5 lb copper

sulfatge

Babadoost

Controlling Bacterial Spot(Summary)- Bacterial spot occurs on twigs, leaves, and fruit.

- Infections of fruit can cause significant economic loss.- Fruit infection is most severe in years when frequent

periods of rainfall occur during the 3 to 4 weeksfollowing petal fall (until pit-hardening).

- Sprays of fixed copper from dormant bud throughshuck split can reduce fruit infection. Coversprays containing Mycoshield and/or low rates ofcopper can reduce fruit loss.

- Time of applications is critical; sprays should beapplied prior to rainfall, but with sufficient time forthe chemicals to dry.

- Chemical sprays, however, are not totally effective onhighly susceptible cultivars in years whenconditions for bacterial spot are very favorable.

Bacterial Spot vs Scab

Peach bacterial spot Peach scab

Bacterial Spot vs Scab

Scab Pathogen: A fungus

(Cladosporium carpophyllium)

Symptoms: spots on fruit and twigs.Spot on fruit are circular, dark brownfuzzy appearance, no fruit surfacepitting, skin cracking may occur. Noleaf symptoms.

Brown Spot of Stone Fruit

Babadoost

Brown rotof stonefruit

Characteristics of Brown Rot_______________________________________

Pathogen: Monilinia fructicola

Crop losses: up to 100%

Major symptoms: blossom blight,spur blight, fruit rot

Fruit rot: at ripening

Favorable conditions: wet, warm

Inoculum: ascospores, conidia

Inoculum sources: mummies,twig canker

Disease cycle of brown rot of stone fruit

Overwintering of Monilinia fructicola

Sporulation ofMonilinia fructicolain spring

Blossom infection by Monilinia fructicola

Managing Brown Rot

Of Stone Fruit___________________________

Disease management

(general):

Minimize the primary inoculum (X0)

Minimize spread of the disease (r)

Brown rot management:

Minimize the primary inoculum (X0)

Management of Stone Fruit Brown Rot___________________________________________________

Sanitation

Destroy rotted fruit

Remove mommies

Prune blighted twigs

Use clean containers for harvesting

Cultural practices

Prune to ensure spray coverage and air-movement

Disk the ground in spring to prevent sporeproduction

Remove wild and neglected stone fruit trees

Management of Stone Fruit Brown Rot___________________________________________________

Spray application Fungicide applications from pink bud until

petal fall Control insects Fungicide applications prior to harvest

Varieties No variety is immune Japanese and American plumes are less

susceptible Thin-skinned and soft-flesh peaches are more

susceptible

Harvest and packing Avoid bruising, scratching, and abrasions Cool and refrigerate (32F) immediately

Fungicide Efficacy for Stone Fruit Brown Rot

Fungicide

BrownR.

BloomBrownR. Fruit Fungicide

Brown R.Bloom

BrownR. Fruit

Adament E E Procure* G

Bravo G --- Rally* E G

Captan G F-G Rovral E ---

Captevate E E Quash G E

Elevate E E Quadr. Top E E

Fontelis E E Quilt Xcel E E

Indar* E E Scala G G

Inspir Super E E Sulfur F P

Luna Sensa. E E Syllit* --- P

Merivan E E Topguard E E

Orbit* E E Topsin-M* E E

Pristine G G Vangard G G

P = poor; F = fair; G = good; E = excellent; --- = unknown.* = resistance reported.

Babadoost

Illinois Peach

Questions/Comments