Managing Stone Fruit Diseases and Updates on the Spray Guides Mohammad Babadoost University of Illinois babadoos@illinois.edu 3-4 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, 2015 Common Name Trade Name Crop Diseases Kasugamycin hydrochloride [FRAC Code: 24] Kasumin 2L Apple Fire blight Pear Fire blight Fluazinam [FRAC Code: 29] Omega 500F Apple Scab, sooty blotch, flyspeck, bitter rot, black rot, white rot, rust, Alternaria blotch (also mites) Dodine [FRAC Code: M] Fluopyram [FRAC Code: 7] Syllit FL Apple Scab, powdery mildew, rust Luna Privilege 4.16FL Apple Cherry (sweet & tart) Strawberry Scab, powdery mildew, sooty blotch, flyspeck Brown rot, shot hole, powdery mildew, scab, cherry leaf spot, Botrytis fruit rot Powdery mildew
New Fungicides/Bactericides for Fruit Crops, 2015 Common Name Trade Name Crop Diseases Azoxystrobin + Difenoconazole [FRAC Code: 11+3] Quadris Top 1.67SC Stone fruit (apricots, cherries, nectarines, peaches, plums, prunes) Alternaria spot, anthracnose, brown rot (blossom blight and fruit rot), leaf rust, powdery mildew, scab, shot hole Blueberry, Strawberry, and other berries (see the label) Anthracnose, leaf rust, leaf spot, powdery mildew Grape Several diseases Quadris Top is phytotoxic to some apple cultivars (e.g., McIntosh). Be extremely careful of the drift of Quadris Top onto apples. Do not use the same sprayer for apples and stone fruit, if you are using Quadris Top. Babadoost
New Fungicides/Bactericides for Fruit Crops, 2015 Common Name Trade Name Crop Diseases Azoxystrobin + Propiconazole [FRAC Code: 11+3] Quilt Xcel 2.2SC Stone fruit (apricots, cherries, nectarines, peaches, plums, prunes) Alternaria spot, anthracnose, brown rot (blossom blight and fruit rot), cherry leaf spot, leaf rust, powdery mildew, scab, shot hole Blackberry, raspberry, and other berries (see the label) Anthracnose, Botryosphaeria canker, rosette (Cercospora spot), leaf and cane spot, powdery mildew, rust Strawberry Anthracnose, leaf rust, leaf spot, powdery mildew Quadris Top is phytotoxic to some apple cultivars (e.g., McIntosh). Be extremely careful of the drift of Quadris Top onto apples. Do not use the same sprayer for apples and stone fruit, if you are using Quadris Top. Babadoost
Important Notes Use streptomycin (e.g., Agri-Mycin 17). If the pathogen is resistant to streptomycin, then use Kasumin 2L (kasugamycin) Azoxystrobin (Abound, Quadris, Quadris Top, Quilt Xcel, ) are phytotoxic on some apple cultivar. Babadoost
Bacterial Spot of Stone Fruit Diseases Babadoost
Lesions on upper leaf surface Lesions on lower leaf surface Bacterial spot of peach: leaf symptoms Babadoost
Bacterial spot of peach: leaf chlorosis Babadoost
Bacterial Spot: Fruit Symptoms Infected Fruit Infected Fruit Infected Fruits at Harvest
Bacterial spot: symptom development on an individual peach fruit 26 Jun 1 Jul 24 Jul 8 Jul 30 Jul 15 Jul 5 Aug 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. Higher disease severity in sandy soil.
Management of Bacterial Spot Control of the disease: challenging Disease resistance: resistance of peaches and nectarines varies in susceptibility/resistance (see attached handout) Nutrient stress: higher disease severity Sandy soil: prevent sand blowing Chemical use: copper, oxytentracycline
What Coppers Can and Cannot Do THY CAN: - Prevent/delay the start of the epidemic - Slow the progress of the epidemic THY CANNOT: - Stop the epidemic as long as conditions remain favorable for infection and disease development - radicate/cure infections
Applications of Copper Sprays 2.0-2.5 lb Cu/A 1.5-2.0 lb Cu/A arly bud-break Pink-bud 1.0 lb Cu/A Blossoms opening
Applications of Copper Sprays 0.50 lb Cu/A 0.10-0.25 lb Cu/A (+ Mycoshield) Petal-fall Shuck-split/Shuck-off Copper phytotoxicity may begin to occur
Copper (Cu) in the Compounds Kocide: Cu(OH)2, 64 Cu/98 Cu (OH)2 For 2 lb Cu, 3 lb Kocide needed Copper sulfate: CuSO4, 64 Cu/160 CuSO4 For 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 weeks following petal fall (until pit-hardening). - Sprays of fixed copper from dormant bud through shuck split can reduce fruit infection. Cover sprays containing Mycoshield and/or low rates of copper can reduce fruit loss. - Time of applications is critical; sprays should be applied prior to rainfall, but with sufficient time for the chemicals to dry. - Chemical sprays, however, are not totally effective on highly susceptible cultivars in years when conditions 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 brown fuzzy appearance, no fruit surface pitting, skin cracking may occur. No leaf symptoms.
Brown Spot of Stone Fruit Babadoost
Brown rot of stone fruit
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 of Monilinia fructicola in 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 airmovement Disk the ground in spring to prevent spore production 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 (32 F) immediately
Fungicide fficacy for Stone Fruit Brown Rot Fungicide BrownR. Brown Bloom R. Fruit Brown R. Brown R. Fruit Fungicide Bloom Adament Procure* G Bravo G --- Rally* G Captan G F-G Rovral --- Captevate Quash G levate Quadr. Top Fontelis Quilt Xcel Indar* Scala G G Inspir Super Sulfur F P Luna Sensa. Syllit* --- P Merivan Topguard Orbit* Topsin-M* Pristine G G Vangard G G P = poor; F = fair; G = good; = excellent; --- = unknown. * = resistance reported.
Illinois Peach Questions/Comments Babadoost