Fruit Crops Apples. Diseases of Apples and Fungicides Labeled for Control

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1 Diseases of and Fungicides Labeled for Control Disease Bitter Rot (Glomerella cingulata = Colletotrichum gloeosporioides) Symptoms: Although infection can occur at any stage of fruit development, most infection occurs after mid as the fruit approaches maturity. The disease is characterized by sunken and (more or less) soft and watery, pinkish to brown rotten spots on the fruit. The rotten tissue has a bitter taste. Source of Inoculum: The fungus survives from to in mummified fruit and in dead wood and cankers. Fungal spores are dispersed primarily in splashing water, and disease develops best under warm, moist conditions. Control: Remove mummified fruit and dead wood. Follow the apple spray schedule; late cover sprays are important. Cedar Apple Rust (Gymnosporangium juniperi virginianae) Symptoms: Galls or cedar apples are produced on eastern red cedar and yellow orange spots are produced on the leaves and fruit of apples and crabapples. Source of Inoculum: The cedar apple rust fungus survives from to on the familiar cedar apples on eastern red cedar. Wind borne spores are produced during periods of rain in the spring. Control: Rust can be avoided by eradicating cedar trees within 2 miles of apples. Follow the apple spray schedule. Fire Blight (Erwinia amylovora) Symptoms: Affects blossoms, leaves, twigs and young fruit. Infected blossoms wilt suddenly and turn dark brown, followed by blighting of leaves and terminals. Infected twigs and leaves turn dark brown to black, and leaves cling to the stem, often remaining attached most of the. Source of Inoculum: The bacteria overwinter at the base of blighted twigs or in cankers on larger limbs. Bacteria are spread by bees and splashing rains. Control: Spray during bloom with copper fungicides or streptomycin according to manufacturer s directions. Prune out and burn infected twigs. Cut inches below affected tissue. Dip pruning tools in 10 percent chlorine bleach solution between cuts. Phytophthora Crown, Collar and Root Rot (Phytophthora spp.) Symptoms: Foliar symptoms include thinning of the canopy, poor Fungicides a Adament (tebuconazole + trifloxystrobin) b Captan, Captec (captan) Flint (trifloxystrobin) b Pristine (boscalid + pyraclostrobin) Thiophanate Methyl (thiophanate methyl) Ziram (ziram) Adament (tebuconazole + trifloxystrobin) Bayleton (triadimefon) Cuprofix (copper sulfate) Flint (trifloxystrobin) Inspire Super (cyprodinil + difenoconazole Penncozeb (mancozeb) Pristine (boscalid + pyraclostrobin) b Procure (triflumizole) Rally (myclobutanil) Sovran (kresoxim methyl) b Tebuzol (tebuconazole) Ziram (ziram) Agri mycin, Firewall (streptomycin sulfate) Aliette, Legion (aluminum tris) Champ, Champion, Kocide, Stretch (copper hydroxide) Cuprofix (copper sulfate) ManKocide (copper hydroxide + mancozeb) b Nordox (cuprous oxide) Aliette, Legion (aluminum tris) Champ, Champion, Kocide, Stretch

2 Disease shoot growth and gradual decline. Removal of the outer bark reveals a reddish brown to brown decay of the phloem and cambium with distinct margins between diseased and healthy tissue. Source of Inoculum: These pathogens are soil borne organisms. Control: Use a combination of practices, including proper site selection, improving drainage and managing soil water, using resistant rootstocks and preventative applications of selected fungicides. Fungicides a (copper hydroxide) Cuprofix (copper sulfate) ManKocide (copper hydroxide + mancozeb) MetaStar (metalaxyl) Ridomil (mefenoxam) a name (chemical name) b For disease suppression only. Fungicide Spray Schedule for Developmental Stage Disease(s) Delayed Dormant to ½ Green Tip Scab Tight Cluster, Pre Pink Scab and powdery mildew Pink Scab, powdery mildew and cedar apple rust Bloom Fire blight, scab, powdery mildew and cedar apple rust Petal Fall Fire blight, scab, powdery mildew and cedar apple rust First Cover Spray Scab, powdery mildew, cedar apple rust and fruit rots Second Cover Spray Scab and fruit rots Third Through Seventh Cover Sprays Scab, fruit rots, sooty blotch and fly speck

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4 Fungicides Labeled for Use on aluminum tris (O ethyl phosphonate) Aliette Legion 80 WDG (in 500 gallons water) (0.5 1 pound/ 100gallons) See label; do not apply within two three weeks of leaf senescence; do not mix with copper fungicides boscalid + pyraclostrobin Pristine WDG to 10 day interval; no more than two sequential applications; no more than four applications or 74 per acre per captan Captan, Captec 50 WP 80 WDG 4L quarts 2.5, 1.6 and 1.25 quarts/ 100 gallons water See label; no more than 64, 40 or 32 quarts per acre per year For post harvest treatment of fruit M4 0 copper hydroxide Champ, Champion, Kocide, Stretch Metallic copper 2.16% 15% 24.4% 30% 35% 37.5% 40% 50% Spray / Drench 2 8 / pint / 5.33 pint / 2.75 pint / / / / / 4 See label; may cause injury to sensitive varieties; for control of fire blight only from silver tip to green tip; do not use in spray solution with ph less than 6.5; for control of crown and root rot, mix in 100 gallons of water and drench 4 gallons per tree; do not apply to soil with a ph of less than 5.5 M1 1 2 copper hydroxide + mancozeb ManKocide Metallic copper 30% Spray / Drench 8 16 / per acre per ; do not graze livestock in treated M1 + M3 NA

5 orchards copper oxychloride + copper hydroxide Badge X 2 Metallic copper 28% s Cu 2+ per acre per year; may cause injury. M1 2 copper sulfate Cuprofix Metallic copper 20% 40% / / 2.5 See label; may cause injury to sensitive varieties; for control of fire blight only from silver tip to green tip; do not use in spray solution with ph less than 6.5; for control of crown and root rot, mix in 100 gallons of water and drench 4 gallons per tree; do not apply to soil with a ph of less than 5.5 M1 0.5 cuprous oxide Nordox Metallic copper 50.1% 1 16 See label; may cause injury to sensitive varieties; M1 1 cyprodinil Vangard 75 WG 5 (alone) 3 5 (tank mix) See label; 7 to 10 day interval; no more than 22 per acre per 9 72 cyprodinil + difenoconazole Inspire Super EC fluid two sequential applications; no more than 60 fluid per acre per difenoconazole Inspire Super MP 2.08 EC 4 fluid See label; tank mix with Vangard; no more than 20 fluid per acre per 3 72 fenarimol Rubigan Vintage 1 EC 8 12 fluid See label; 7 to 14 day interval; no more than 84 fluid per acre per 3 30

6 fenbuconazole Indar 2F 75 WSP 6 8 fluid 2.67 four applications, 32 fluid or per acre per ; do not graze livestock in treated orchards 3 14 fludioxonil Scholar 1.92 SC fluid /100 gallons fluid / 200,000 of fruit See label; for postharvest fruit treatment; for best decay control, apply once prior to and once after storage, just prior to marketing 12 NA kresoximmethyl Sovran 50 WG two sequential applications; no more than four applications or 25.6 per acre per mancozeb Dithane, Manzate, Penncozeb 4 F 75 DF 80 WP 4.8 quarts, 6.4 or quarts, 3.2 or 3 See label; use higher rates only in a prebloom spray schedule; use lower rates only in an extended application schedule; use one schedule or the other, do not combine or integrate them; do not graze livestock in treated orchards M3 77 mefenoxam Ridomil 4 EC 4 SL 2 quarts per acre or 1.5 fluid per 1,000 square feet as a soil spray See label; apply in early spring before growth starts and in the fall after harvest. 4 NA 0.5 pint per 100 gallons of water as a soil drench

7 metalaxyl MetaStar 2E AG 2 gallons per acre or 6 fluid per 1,000 square feet as a soil spray 1 quart per 100 gallons as a soil drench See label; apply in early spring before growth starts and in the fall after harvest. 4 NA myclobutanil Rally 40 WSP per acre per 3 14 oxytetracycline calcium complex Mycoshield 17% 16 /100 gallons (200 ppm) five applications per ; begin spraying at 10 percent bloom; 3 to 6 day interval; do not graze livestock in treated orchards phosphite (phosphorous acid salts) Alude, Fosphite, Fungi phite, Helena Prophyt, Phorcephite, Phostrol, Rampart, Topaz Phosphorous acid (lb/gal) 1 2 quarts 1 3 quarts 2 4 pints pints See label pyrimethanil Scala SC 7 10 fluid (alone) 5 fluid (tank mix) 40 fluid per acre per ; use lower rate only when tank mixed with another product labeled for the same use 9 72 streptomycin sulfate Agri Mycin 17, Firewall 17% a.i ( ppm at 600 gallons per acre)) Begin spraying at percent bloom, then every three to four days during remainder of bloom; spray every days after petal fall to control twig blight 25 50

8 sulfur IAP Dusting Sulfur, Liquid Sulfur Six, Microthiol Disperss, Super Six Liquid Sulfur, Thiolux Jet, 80% Thiosperse, Wettable Sulfur 53% L 80% 90% 98% pints See label; do not use when hot or when temperatures are expected to be above 90 degrees F over the next three days; do not use within two weeks of an oil spray M2 1 tebuconazole Tebuzol 45 DF 4 8 (2 per 100 gallons) 3 per acre per 3 75 tebuconazole + trifloxystrobin Adament 50 WG when tank mixed with captan (1.2 a.i.) two sequential applications; no more than four applications or 22 per acre per thiabendazole Mertect 340 F 16 fluid per 100 gallons See label; for use as a post harvest fruit treatment; do not treat for more than three minutes. 1 NA thiophanatemethyl Thiophanatemethyl, Topsin, T Methyl 4.5 FL 70 WP 85 WDG fluid pound 80 fluid, 4 or 3.3 per acre per, respectively 1 1 triflumizole Procure 50 W 480 SC fluid See label; should be tank mixed with another labeled fungicide; no more than 64 or 64 fluid per acre per ; follow rotational crop restrictions 3 14 trifloxystrobin Flint 50 WP

9 two sequential applications; no more than four applications or 11 per acre per ziram Ziram 76 DF per acre per M3 14