Disease Control

The most common controls for garlic diseases include the use of disease-resistant cultivars and pathogen-free seed and bulbs, as well as cultural practices including crop rotation and crop residue management that restrict the pathogens. 

Blue Mold Rot (Penicillium spp.)

Blue mold is typically most problematic as a storage disease, although planting infected seed cloves can result in poor stands. Several Penicillium species cause blue mold, and these species are common in soil, on plant and animal debris, and in senescing plant tissues. Some species may be carried on infected cloves or seed. The fungus presents as a mass of gray to blue-gray fungal growth on the bulb, and in the field, yellowed, and stunted plants may be observed. These pathogens are opportunistic and typically invade bulbs through wounds, mechanical bruises, or freezing injury. Control other diseases and pests in the field to prevent avenues for infection. Harvest and handle bulbs gently and dry promptly. Store bulbs at 40°F with low relative humidity. Do not plant cloves from bulbs with mycelium, and plant soon after separating cloves to prevent potential spore spread.

FRAC Group 1:

• thiophanate methyl (Topsin M WSB): 1 lb/100 gal; REI 12h. Pre-plant treatment by immersion of garlic cloves in suspension for at least 5 minutes. Continuous agitation during application is required. Dry cloves prior to planting. 

Botrytis Neck Rot (Botrytis porri)

Botrytis porri causes neck rot of garlic and leeks. It is distinct from Botrytis allii and Botrytis aclada, which cause neck rot of onion. The pathogen is soil- and seed-borne and is readily spread through planting of infected gloves or seed. Symptoms may appear shortly before harvest or after harvest in garlic that is not cured or stored correctly. In the field, plants may appear stunted and leaves may die back. Water-soaked lesions may be seen on the neck near the soil line. Infected seeds may fail to germinate. Under moist conditions, a gray mold may develop on the surface of or between garlic scales, and distinct black sclerotia later appear around the rotting neck. These sclerotia germinate in spring and release thousands of spores, which can be wind-carried to susceptible host plants, starting new disease cycles. Under warm and wet conditions, the disease progresses quickly.  Plant certified disease-free cloves and minimize bruising or mechanical injury, especially during harvest and topping. Avoid excessive nitrogen application, which delays crop maturity and curing. Inspect plants for symptoms and signs of disease during the season as well as at harvest since plants may become infected in the field but will remain symptomless until they are in storage. Practice crop rotation and destroy and remove crop residue after harvest.

FRAC Group 3:

• azoxystrobin + difenoconazole (Quadris Top): 12 to 14 fl oz/A; PHI 7d, REI 12h, Groups 11 & 3. 
• difenoconazole + cyprodinil (Inspire Super): 16 to 20 fl oz/A; PHI 7d, REI 12h, Groups 3 & 9. Apply in sufficient volume to achieve thorough coverage. 
• difenoconazole + fluopyram (Luna Flex): 10 to 13.6 fl oz/A; PHI 7d, REI 12h, Groups 3 & 7. 
• tebuconazole + fluopyram (Luna Experience): 8 to 12.8 fl oz/A; PHI 7d, REI 12h, Groups 3 & 7.

FRAC Group 7:

• difenoconazole + fluopyram (Luna Flex): 10 to 13.6 fl oz/A; PHI 7d, REI 12h, Groups 3 & 7. 
• penthiopyrad (Fontelis): 16 to 24 oz/A; PHI 3d, REI 12h. 
• pydiflumetofen + fludioxonil (Miravis Prime): 11.4 fl oz/A; PHI 7d, REI 12h, Groups 12 & 7. Apply preventively, in sufficient volume to achieve thorough coverage.
• pyraclostrobin + fluxapyroxad (Merivon Xemium): 8 to 11 fl oz/A; PHI 7d, REI 12h, Groups 11 & 7. 
• pyrimethanil + fluopyram (Luna Tranquility): 16 to 27 fl oz/A; PHI 7d, REI 12h, Groups 9 & 7.
• tebuconazole + fluopyram (Luna Experience): 8 to 12.8 fl oz/A; PHI 7d, REI 12h, Groups 3 & 7.

FRAC Group 9:

• cyprodinil (Vangard WG): 5.5 to 10 oz/A; PHI 7d, REI 12h. Thorough plant coverage is essential.
• cyprodinil + fludioxonil (Switch 62.5 WG): 11 to 14 oz/A; PHI 0d, REI 12h, Groups 9 & 12. Suppression only.
• difenoconazole + cyprodinil (Inspire Super): 16 to 20 fl oz/A; PHI 7d, REI 12h, Groups 3 & 9. Apply in sufficient volume to achieve thorough coverage. 
• pyrimethanil + fluopyram (Luna Tranquility): 16 to 27 fl oz/A; PHI 7d, REI 12h, Groups 9 & 7.

FRAC Group 11:

• azoxystrobin + difenoconazole (Quadris Top): 12 to 14 fl oz/A; PHI 7d, REI 12h, Groups 11 & 3. 
• pyraclostrobin (Cabrio EG): 12 oz/A; PHI 7d, REI 12h. Suppression only.
• pyraclostrobin + fluxapyroxad (Merivon Xemium): 8 to 11 fl oz/A; PHI 7d, REI 12h, Groups 11 & 7.

FRAC Group 12:

• cyprodinil + fludioxonil (Switch 62.5 WG): 11 to 14 oz/A; PHI 0d, REI 12h, Groups 9 & 12. Suppression only.
• pydiflumetofen + fludioxonil (Miravis Prime): 11.4 fl oz/A; PHI 7d, REI 12h, Groups 12 & 7. Apply preventively, in sufficient volume to achieve thorough coverage.

FRAC Group 22:

• chlorothalonil + zoxamide (Zing!): 30 fl oz/A; PHI 7d, REI 12h, Groups 22 & M05. Do not apply to exposed bulbs.

FRAC Group 29:

• fluazinam (Omega 500DF): 16 fl oz/A; PHI 7d, REI 12h. Do not make more than 6 applications per acre per year. Do not use an adjuvant on this crop. 

FRAC Group 49:

• chlorothalonil + oxathiapiprolin (Orondis Opti): 1.75 to 5 pt/A; PHI 7d, REI 12h, Groups 49 & M05.

FRAC Group BM02:

• Bacillus amyloliquefaciens strain D747 (Double Nickel 55^OG): 0.25 to 3 lb/A (foliar); PHI 0d, REI 4h.
• Pseudomonas chlororaphis strain AFS009 (Howler EVO^OG): 2.5 to 7.5 lb/A; PHI 0d, REI 4h. Use preventatively. 
• Streptomyces lydicus strain WYEC 108 (Actinovate AG^OG): 3 to 12 oz/A (soil-applied); PHI 0d, REI 4h.

FRAC Group M01:

• copper octanoate (Cueva^OG): 38 gal/A, 112 fl oz/1000 sq ft; PHI 0d, REI 4h. 

FRAC Group M05:

• chlorothalonil (Echo 720): 1 to 3 pt/A; PHI 14d, REI 12h. 
• chlorothalonil + oxathiapiprolin (Orondis Opti): 1.75 to 5 pt/A; PHI 7d, REI 12h, Groups 49 & M05.
• chlorothalonil + zoxamide (Zing!): 30 fl oz/A; PHI 7d, REI 12h, Groups 22 & M05. Do not apply to exposed bulbs.

FRAC Group NC:

• hydrogen peroxide + peroxyacetic acid (Oxidate 2.0^OG): 1:40 (rescue), 1:100 dilution (curative), or 1:200 to 1:400 dilution (preventative); PHI 0d, REI until sprays dry (field), 1h fogging/spraying or 0h other methods (enclosed areas). Do not tank mix with copper. 

FRAC Group P04:

• laminarin (Vacciplant): 14 to 22 fl oz/A; PHI 0d, REI 4h.

Bulb and Basal Plate Rot (Fusarium spp.)

Bulb and basal plate rot of garlic is caused by several Fusarium species. Symptoms include pre-emergence decay of cloves and seedlings, decay of the stem plate and storage leaves during the growing season, and postharvest decay of cloves in stored bulbs. Infected cloves will have sunken, circular brown lesions on their outer surface and/or basal plate. Foliar symptoms may include curving, yellowing and necrosis of leaves beginning at tips, and wilt. Infection occurs mainly from the soil through the stem plate. Incidence of the disease increases with injury by onion maggot or other insects. Cloves may remain infected but non-symptomatic. The pathogen is disseminated in seed, soil, infected debris, and soil/irrigation water. Hot water seed treatment has reduced garlic clove infection by 50%, but is not enough to provide commercially acceptable control when clove infection is severe and is a logistically difficult process. Excess soil N favors Fusarium infection: take care to account for soil organic matter and cover crop N credits when fertilizing. Long (4-year) rotations to non-susceptible crops may minimize losses. Storage at 40°F also helps.

Damping-off and Seed Rot (Pythium and Rhizoctonia spp.)

Damping-off and seed rot typically occur in poorly drained soil. Seeds and roots of infected seedlings will appear water-soaked, then will decompose. Plants infected after the seedling stage will have leaves yellowing from tip to base. Avoid excessive soil moisture by improving soil drainage and planting in raised beds. Seed and soil treatments with fungicides are a recommended practice.

FRAC Group 4:

• mefenoxam (Apron XL): 0.085 to 0.64 fl oz/100 lb seed; REI 48h. Not effective for Rhizoctonia. 
• mefenoxam and mancozeb (Ridomil Gold MZ WG): 2.5 lb/A; PHI 7d, REI 48h, Groups 4 & M03. Use sufficient water to obtain thorough coverage. Do not apply more than 4 times per season.

FRAC Group 12:

• fludioxonil (Maxim 4FS): 0.08 to 0.16 oz/100 lb seed; REI 12h. For protection against seedborne and soilborne true fungi. Does not control Pythium or Phytophthora.

Downy Mildew (Peronospora destructor)

See the Onion, Scallion and Shallot disease control section for information about allium downy mildew. 

FRAC Group 3:

• azoxystrobin + propiconazole (Quilt Xcel): 17.5 to 21 fl oz/A; PHI 14d, REI 12h, Groups 11 & 3. May cause phytotoxicity if tank-mixed with EC formulations.

FRAC Group 4:

• mefenoxam + chlorothalonil (Ridomil Gold Bravo SC): 2.5 pt/A; PHI 7d, REI 48h, Groups 4 & M05. 

FRAC Group 11:

• azoxystrobin (Quadris F): 9 to 15.5 fl oz/A; PHI 0d, REI 4h. Do not make more than 1 application before alternating to a non-Group 11 fungicide.
• azoxystrobin + chlorothalonil (Quadris Opti): 2.4 to 3.6 pt/A; PHI 7d, REI 12h, Groups 11 & M05. See label for tank mix precautions. 
• azoxystrobin + propiconazole (Quilt Xcel): 17.5 to 21 fl oz/A; PHI 14d, REI 12h, Groups 11 & 3. May cause phytotoxicity if tank-mixed with EC formulations.
• famoxadone + cymoxanil (Tanos): 8 oz/A; PHI 3d, REI 12h, Groups 11 & 27. Must be tank-mixed with an appropriate contact fungicide from a different FRAC Group. Do not alternate or tank-mix with other Group 11 fungicides.
• fenamidone (Reason 500 SC): 5.5 fl oz/A; PHI 7d, REI 12h. Do not make more than 1 application before alternating to a non-Group 11 fungicide.
• pyraclostrobin (Cabrio EG): 12 oz/A; PHI 7d, REI 12h. Do not make more than 1 application before alternating to a non-Group 11 fungicide.

FRAC Group 27:

• famoxadone + cymoxanil (Tanos): 8 oz/A; PHI 3d, REI 12h, Groups 11 & 27. Must be tank-mixed with an appropriate contact fungicide from a different FRAC Group. Do not alternate or tank-mix with other Group 11 fungicides.

FRAC Group 29:

• fluazinam (Omega 500F): 16 fl oz/A; PHI 7d, REI 12h. Use sufficient water for thorough coverage, but not less than 5 gal/A. Do not use an adjuvant.  

FRAC Group 40:

• ametoctradin + dimethomorph (Zampro): 14 fl oz/A; PHI 0d, REI 12h, Groups 45 & 40.
• dimethomorph (Forum): 6 fl oz/A; PHI 0d, REI 12h. Must be tank-mixed with a non-Group 40 fungicide. Apply in adequate water.
• mandipropamid (Revus): 5.5 to 8 fl oz/A; PHI 7d, REI 4h. A silicone-based adjuvant must be added. Make no more than 2 applications before rotating to a non-Group 40 fungicide.
• oxathiapiprolin + mandipropamid (Orondis Ultra): 5.5 to 8 fl oz/A; PHI 7d, REI 4h, Groups 49 & 40. 

FRAC Group 45:

• ametoctradin + dimethomorph (Zampro): 14 fl oz/A; PHI 0d, REI 12h, Groups 45 & 40.

FRAC Group 49:

• oxathiapiprolin + mandipropamid (Orondis Ultra): 5.5 to 8 fl oz/A; PHI 7d, REI 4h, Groups 49 & 40.

FRAC Group BM02:

• Bacillus amyloliquefaciens strain D747 (Double Nickel 55^OG): 0.25 to 3 lb/A (foliar); PHI 0d, REI 4h.

FRAC Group M01:

• copper hydroxide (Kocide 3000): 0.75 to 1.5 lb/A; PHI 0d, REI 48h. May cause phytotoxicity to leaves. Do not apply in a spray solution having a pH less than 6.5 or tank mix with Aliette. An OMRI-listed formulation is available (Kocide 3000-O^OG).

FRAC Group M03:

• mancozeb (Dithane F45): 2.4 qt/A; PHI 7d, REI 24h. Do not apply to exposed bulbs. 
• mefenoxam and mancozeb (Ridomil Gold MZ WG): 2.5 lb/A; PHI 7d, REI 48h, Groups 4 & M03. Use sufficient water to obtain thorough coverage. Do not apply more than 4 times per season.

FRAC Group M05:

• azoxystrobin + chlorothalonil (Quadris Opti): 2.4 to 3.6 pt/A; PHI 7d, REI 12h, Groups 11 & M05. See label for tank-mix precautions. 
• mefenoxam + chlorothalonil (Ridomil Gold Bravo SC): 2.5 pt/A; PHI 7d, REI 48h, Groups 4 & M05. 

FRAC Group P07:

• phosphorous acid (Fosphite): 1 to 3 qt/in a minimum of 20 gal/A; PHI 0d, REI 4h. Do not apply to plants that heat- or moisture-stressed. Do not apply directly to copper-treated plants within 20-day interval to avoid plant injury.

Garlic Bloat Nematode (Ditylenchus dipsaci)

Ditylenchus dipsaci is a nematode species that infects germinating garlic seed and is primarily borne in seed cloves as well as onion. The nematode itself has limited mobility, but can be easily spread in infested soil, on equipment, and in infected seed and plant material. D. dipsaci is common in all temperate regions. It is an obligate parasite of plants, and populations of the nematode exhibit marked host preferences. The nematodes aggregate into a mass called nematode wool and with slow drying can persist in infested fields for extended periods. Symptoms of infection include leaf yellowing, erratic stands, stunting, looping, and bending of leaves, twisting, and growth deformities since nematodes feed on roots and eventually the basal plate and bulb.  Bulb damage can be mistaken for Fusarium basal plate rot with decay occurring both at the neck and the basal plate. Infected bulbs often will lack some or all roots, and have a puffy, swollen, or bloated appearance. D. dipsaci can be controlled with long crop rotations including the elimination of volunteer onions, garlic, and host weeds. The primary method of controlling nematodes is hot water treatment of seed cloves but this process is difficult to do on-farm because of the large volume of water needed to be held at a specific temperature for treatment. The standard regime is 30–45 minutes at 100ºF, 20 minutes at 120ºF, and then 10–20 minutes at 64ºF–72ºF. Hot water treatment must be performed carefully to prevent damage to cloves. Chemical, physical, and cultural methods have been used to restrict damage, but most chemical treatments are no longer registered for use. The best control is prevention by sourcing seed from sources that have subjected their seed lot for seed garlic testing.

Purple Blotch (Alternaria porri)

See the Onion, Scallion & Shallot disease control section for information about purple blotch.

FRAC Group 3:

• azoxystrobin + difenoconazole (Quadris Top): 12 to 14 fl oz/A; PHI 7d, REI 12h, Groups 11 & 3. 
• azoxystrobin + propiconazole (Quilt): 14 to 21 fl oz/A; PHI 14d, REI 12h, Groups 11 & 3. Make only 1 application before alternating to a non-Group 11 fungicide. See label for phytotoxicity warnings.
• difenoconazole + cyprodinil (Inspire Super): 16 to 20 fl oz/A; PHI 7d, REI 12h, Group 3 & 9. Apply in sufficient volume to achieve thorough coverage.
• difenoconazole + fluopyram (Luna Flex): 10 to 13.6 fl oz/A; PHI 7d, REI 12h, Groups 3 & 7.
• propiconazole (Tilt): 4 to 8 fl oz/A; PHI 14d, REI 24h. Apply in sufficient water to provide thorough coverage. Most effective when applied and allowed to dry. 

FRAC Group 4:

• mefenoxam + chlorothalonil (Ridomil Gold Bravo SC): 2.5 pt/A; PHI 7d, REI 48h, Groups 4 & M05.

FRAC Group 7:

• boscalid (Endura): 6.8 oz/A; PHI 7d, REI 12h. Do not make more than 2 consecutive applications before rotating to a non-Group 7 fungicide.
• difenoconazole + fluopyram (Luna Flex): 10 to 13.6 fl oz/A; PHI 7d, REI 12h, Groups 3 & 7.

• fluopyram (Velum Prime): 6.5 to 6.84 fl oz/A; PHI 30d, REI 12h. Note longer PHI.

• penthiopyrad (Fontelis): 16 to 24 oz/A; PHI 3d, REI 12h. 
• pydiflumetofen + fludioxonil (Miravis Prime): 6.8 to 11.4 fl oz/A; PHI 7d, REI 12h, Groups 12 & 7. Apply in sufficient volume to achieve thorough coverage.
• pyraclostrobin + boscalid (Pristine): 10.5 to 18.5 oz/A; PHI 7d, REI 12h, Groups 11 & 7. Do not make more than 2 applications before alternating with a non-Group 7 fungicide.

• pyrimethanil + fluopyram (Luna Tranquility): 16 to 27 fl oz/A; PHI 7d, REI 12h, Groups 9 & 7.

FRAC Group 9:

• cyprodinil + fludioxonil (Switch 62.5 WG): 11 to 14 oz/A; PHI 7d, REI 12h, Groups 9 & 12. Do not make more than 2 consecutive applications before rotating to a non-Group 9 fungicide. 
• difenoconazole + cyprodinil (Inspire Super): 16 to 20 fl oz/A; PHI 7d, REI 12h, Group 3 & 9. Apply in sufficient volume to achieve thorough coverage.
• pyrimethanil (Scala SC): 18 fl oz/A; PHI 7d, REI 12h.

• pyrimethanil + fluopyram (Luna Tranquility): 16 to 27 fl oz/A; PHI 7d, REI 12h, Groups 9 & 7.

FRAC Group 11:

• azoxystrobin (Quadris F): 6 to 12 fl oz/A; PHI 0d, REI 4h. Do not rotate with other Group 11 fungicides.
• azoxystrobin + chlorothalonil (Quadris Opti): 1.6 to 3.2 pt/A; PHI 7d, REI 12h, Groups 11 & M05. See label for tank mix precautions. 
• azoxystrobin + difenoconazole (Quadris Top): 12 to 14 fl oz/A; PHI 7d, REI 12h, Groups 11 & 3. 
• azoxystrobin + propiconazole (Quilt): 14 to 21 fl oz/A; PHI 14d, REI 12h, Groups 11 & 3. Make only 1 application before alternating to a non-Group 11 fungicide. See label for phytotoxicity warnings. 
• famoxadone + cymoxanil (Tanos): 8 oz/A; PHI 3d, REI 12h, Groups 11 & 27. Must be tank mixed with an appropriate contact fungicide from a different FRAC Group. Do not alternate or tank-mix with other Group 11 fungicides. 
• fenamidone (Reason 500 SC): 5.5 fl oz/A; PHI 7d, REI 12h. Do not make more than 1 application before alternating to a non-Group 11 fungicide.
• pyraclostrobin (Cabrio EG): 8 to 12 oz/A; PHI 7d, REI 12h. Do not rotate with other Group 11 fungicides.
• pyraclostrobin + boscalid (Pristine): 10.5 to 18.5 oz/A; PHI 7d, REI 12h, Groups 11 & 7. Do not make more than 2 applications before alternating with a fungicide from a different FRAC Group.

FRAC Group 12:

• cyprodinil + fludioxonil (Switch 62.5 WG): 11 to 14 oz/A; PHI 7d, REI 12h, Groups 9 & 12. Do not make more than 2 consecutive applications before rotating to a non-Group 9 or 12 fungicide. 
• pydiflumetofen + fludioxonil (Miravis Prime): 6.8 to 11.4 fl oz/A; PHI 7d, REI 12h, Groups 12 & 7. Apply in sufficient volume to achieve thorough coverage.

FRAC Group 19:

• polyoxin D (OSO 5%SC): 6.5 to 13 fl oz/A; PHI 0d, REI 4h. Apply preventatively as a foliar spray.

FRAC Group 22:

• chlorothalonil + zoxamide (Zing!): 30 fl oz/A; PHI 7d, REI 12h, Groups 22 & M05. Do not apply to exposed bulbs.

FRAC Group 27:

• famoxadone + cymoxanil (Tanos): 8 oz/A; PHI 3d, REI 12h, Groups 11 & 27. Must be tank-mixed with an appropriate contact fungicide from a different FRAC Group. Do not alternate or tank-mix with other Group 11 fungicides. 

FRAC Group 29:

• fluazinam (Omega 500DF): 16 fl oz/A; PHI 7d, REI 12h. Do not make more than 6 applications per acre per year. Do not use an adjuvant on this crop. 

FRAC Group 49:

• chlorothalonil + oxathiapiprolin (Orondis Opti): 1.75 to 5 pt/A; PHI 7d, REI 12h, Groups 49 & M05.

FRAC Group BM02:

• Bacillus amyloliquefaciens strain D747 (Double Nickel 55^OG): 0.25 to 3 lb/A (foliar); PHI 0d, REI 4h.
• Pseudomonas chlororaphis strain AFS009 (Howler EVO^OG): 2.5 to 7.5 lb/A; PHI 0d, REI 4h. Use preventatively. 

FRAC Group M01:

• copper hydroxide (Kocide 3000): 0.75 to 1.5 lb/A; PHI 0d, REI 48h. Do not apply in a spray solution having a pH less than 6.5 or tank mix with Aliette. An OMRI-listed formulation is available (Kocide 3000-O^OG).

FRAC Group M03:

• mancozeb (Dithane F45 Rainshield): 2.4 qt/A; PHI 7d, REI 24h. Do not apply to exposed bulbs. 

FRAC Group M05:

• azoxystrobin + chlorothalonil (Quadris Opti): 1.6 to 3.2 pt/A; PHI 7d, REI 12h, Groups 11 & M05. See label for tank mix precautions. 
• chlorothalonil (Bravo Weather Stik): 1 to 3 pt/A; PHI 7d, REI 12h. When disease is present, use the higher rate. Apply in sufficient water to obtain thorough coverage of tops. 
• chlorothalonil + oxathiapiprolin (Orondis Opti): 1.75 to 5 pt/A; PHI 7d, REI 12h, Groups 49 & M05.
• chlorothalonil + zoxamide (Zing!): 30 fl oz/A; PHI 7d, REI 12h, Groups 22 & M05. Do not apply to exposed bulbs.
• mefenoxam + chlorothalonil (Ridomil Gold Bravo SC): 2.5 pt/A; PHI 7d, REI 48h, Groups 4 & M05

Stemphylium Leaf Blight (Stemphylium spp.)

See the Onion, Scallion & Shallot disease control section for information about Stemphylium leaf blight.

FRAC Group 3:

• azoxystrobin + difenoconazole (Quadris Top): 12 to 14 fl oz/A; PHI 7d, REI 12h, Groups 11 & 3. 
• difenoconazole + benzovindiflupyr (Aprovia Top): 10.5 to 13.5 fl oz/A; PHI 7d, REI 12h, Groups 7 & 3. Do not make more than 2 consecutive applications before switching to a non-Group 7 or 3 fungicide.
• difenoconazole + cyprodinil (Inspire Super): 16 to 20 fl oz/A; PHI 7d, REI 12h, Groups 3 & 9. Apply in sufficient volume to achieve thorough coverage. 
• difenoconazole + fluopyram (Luna Flex): 10 to 13.6 fl oz/A; PHI 7d, REI 12h, Groups 3 & 7. 
• tebuconazole + fluopyram (Luna Experience): 12.8 fl oz/A; PHI 7d, REI 12h, Groups 3 & 7.

FRAC Group 7:

• difenoconazole + benzovindiflupyr (Aprovia Top): 10.5 to 13.5 fl oz/A; PHI 7d, REI 12h, Groups 7 & 3. Do not make more than 2 consecutive applications before switching to a non-Group 7 or 3 fungicide.
• difenoconazole + fluopyram (Luna Flex): 10 to 13.6 fl oz/A; PHI 7d, REI 12h, Groups 3 & 7. 
• penthiopyrad (Fontelis): 16 to 24 oz/A; PHI 3d, REI 12h. 
• pydiflumetofen + fludioxonil (Miravis Prime): 6.8 to 11.4 fl oz/A; PHI 7d, REI 12h, Groups 12 & 7. Apply preventatively in sufficient volume to ensure good coverage.
• pyraclostrobin + fluxapyroxad (Merivon Xemium): 4 to 11 fl oz/A; PHI 7d, REI 12h, Groups 11 & 7. Do not apply more than 2 consecutive applications before switching to a non-Group 7 or 11 fungicide.
• pyrimethanil + fluopyram (Luna Tranquility): 16 to 27 fl oz/A; PHI 7d, REI 12h, Groups 9 & 7.
• tebuconazole + fluopyram (Luna Experience): 12.8 fl oz/A; PHI 7d, REI 12h, Groups 3 & 7.

FRAC Group 9:

• cyprodinil + fludioxonil (Switch 62.5 WG): 11 to 14 oz/A; PHI 7d, REI 12h, Groups 9 & 12. 
• difenoconazole + cyprodinil (Inspire Super): 16 to 20 fl oz/A; PHI 7d, REI 12h, Groups 3 & 9. Apply in sufficient volume to achieve thorough coverage. 
• pyrimethanil + fluopyram (Luna Tranquility): 16 to 27 fl oz/A; PHI 7d, REI 12h, Groups 9 & 7.

FRAC Group 11:

• azoxystrobin + difenoconazole (Quadris Top): 12 to 14 fl oz/A; PHI 7d, REI 12h, Groups 11 & 3. 
• pyraclostrobin + fluxapyroxad (Merivon Xemium): 4 to 11 fl oz/A; PHI 7d, REI 12h, Groups 11 & 7. Do not apply more than 2 consecutive applications before switching to a non-Group 7 or 11 fungicide.

FRAC Group 12:

• cyprodinil + fludioxonil (Switch 62.5 WG): 11 to 14 oz/A; PHI 7d, REI 12h, Groups 9 & 12.
• pydiflumetofen + fludioxonil (Miravis Prime): 6.8 to 11.4 fl oz/A; PHI 7d, REI 12h, Groups 12 & 7. Apply preventatively in sufficient volume to ensure good coverage.

FRAC Group BM01:

• thyme oil (Guarda): 1 gal/29–159 gal water (0.625%–3.3% v/v); PHI 0d, REI 0h.

FRAC Group BM02:

• Pseudomonas chlororaphis strain AFS009 (Howler EVO^OG): 2.5 to 7.5 lb/A; PHI 0d, REI 4h. Use preventatively. 

FRAC Group P04: 

• laminarin (Vacciplant): 14 to 22 fl oz/A; PHI 0d, REI 4h. 

White Rot (Sclerotium cepivorum)

White rot is caused by Sclerotium cepivorum, which persists for a long time in soil. It is “activated” by root exudates produced by allium crops. Infected plants will show yellowing older leaves and stunting. White, cottony mycelium appears on infected tissues, but it is rapidly converted to masses of sclerotia. The sclerotia are round, black, and very small (0.35–0.75 mm). Symptoms may be widespread in the field, or they may occur in small patches, which gradually expand. Disease development is favored by cool, moist soil conditions. Purchase disease-free seed and transplants. Avoid planting in fields with a history of white rot; there is little to be done once a field is infested with S. cepivorum, and crops should be rotated out of alliums for as long as possible. Some fungicides provide protection for the establishment of garlic, but fungicide control is marginal for full-season crops. In general, neither fungicides nor soil fumigation have provided consistent, reliable, full-season control of white rot. Hot water treatment of infected garlic seed can reduce the potential to spread white rot sclerotia but is logistically difficult to do, due to the large volume of water needed. Winter flooding and soil solarization can reduce the number of sclerotia.

FRAC Group 1:

• thiophanate methyl (Topsin M 70WP): 2 lb/A; REI 72h. Apply in-furrow at planting. Do not make more than 1 application per year. 

FRAC Group 2:

• iprodione (Rovral): 4 pt/A; REI 24h. Apply in-furrow at planting. Do not make more than 1 application per year.

FRAC Group 3:

• azoxystrobin + propiconazole (Quilt Xcel): 17.5 to 21 fl oz/A; PHI 14d, REI 12h, Groups 11 & 3. See label for phytotoxicity warnings.
• tebuconazole (Orius 3.6F): 20.5 fl oz/A; PHI 7d, REI 12h. Apply in-furrow at planting or over the top in a 4"–6" band.

FRAC Group 7:

• boscalid (Endura): 6.8 oz/A; PHI 7d, REI 12h, Group 7. Apply in-furrow at planting.

FRAC Group 9:

• cyprodinil + fludioxonil (Switch 62.5 WG): 7 to 14 oz/A; PHI 7d, REI 12h, Groups 9 & 12. Apply in-furrow at planting. 

FRAC Group 11:

• azoxystrobin + propiconazole (Quilt Xcel): 17.5 to 21 fl oz/A; PHI 14d, REI 12h, Groups 11 & 3. See label for phytotoxicity warnings.

FRAC Group 12:

• cyprodinil + fludioxonil (Switch 62.5 WG): 7 to 14 oz/A; PHI 7d, REI 12h, Groups 9 & 12. Apply in-furrow at planting. 
• fludioxonil (Cannonball WG): 3.5 to 7 oz/A; PHI 7d, REI 12h. Apply in-furrow at planting.

FRAC Group BM02:

• Bacillus amyloliquefaciens strain D747 (Double Nickel 55^OG): 0.125 to 1 lb/A (soil); PHI 0d, REI 4h.