General Information
Information on chemical plant protectants for disease control on greenhouse vegetables must be used in the context of a "Total Disease Control Program." For example, many diseases are controlled by sanitation (no smoking, fumigating soil, using disease-free seed and seedlings, removing all dead plant parts, and washing hands and equipment before moving from one house to another), use of resistant varieties, crop rotation, seed treatment, exclusion of aphids from fall crops, and cultural practices. Always use top-quality seed or plants obtained from reliable sources. Seed are ordinarily treated by the seed producer for the control of seed decay and damping-off. However, tomato seed also should be treated with Clorox to reduce the risk of tobacco mosaic virus and certain bacterial diseases.
Most foliar diseases can be reduced or controlled by maintaining relative humidity under 90%, by keeping the air circulating in the house, and watering in such a manner to avoid wetting leaves.
Spraying with fungicides should be done as to ensure coverage of all plant surfaces. We recommend the use of high-pressure and high-volume equipment or subliming products (Exotherm Termil). Application should start prior to or as soon as the disease first appears and continued on a 7- to 14-day schedule as needed. Before starting the spray schedule, be sure to obtain a diagnosis of the disease in order to use the proper material. This information may be obtained through your local N.C. Cooperative Extension center.
CAUTION: The risk of pesticide exposure in the greenhouse is high; use protective clothing laundered daily or after each exposure; ventilate house during application and use appropriate respirator. Always use the chemical as directed on the label.
Chemical Controls
Commodity | Disease | Active Ingredient (Trade Name) | FRAC | Rate | PHI (days) | REI (hours) |
---|---|---|---|---|---|---|
Basil | Alternaria leaf spot, Botrytis, Fusarium blight | cyprodinil + fludioxinil (Switch) | 9+12 | 11 to 14 oz/A | 7 | 12h |
Downy mildew | cyazofamid (Ranman) | 21 | 2.75 to 3 fl oz/A | 0 | 12h | |
mandipropamid (Micora, Revus) | 40 | 8.0 fl oz/A | 1 | 4h | ||
Downy mildew, Pythium root rot, Rhizoctonia root rot | phosphorous acid (various) | 33 | See label | See label | See label | |
potassium phosphite (various) | 33 | See label | See label | See label | ||
Cucurbits | Angular leaf spot, Downy mildew | copper, fixed (various) | M1 | See label | See label | See label |
Downy mildew | cymoxanil (Curzate) | 27 | 3.2 to 5.0 oz/A | 3 | 12h | |
Alternaria leaf blight and spot, Gummy stem blight, Powdery mildew | cyprodinil + fludioxinil (Switch) | 9+12 | 11 to 14 oz/A | 1 | 12h | |
Alternaria leaf blight and spot, Anthracnose, Cercospora leaf spot, Gummy stem blight, Powdery mildew, Septoria leaf blight | difenoconazole + cyprodinil (Inspire Super) | 3+9 | 16 to 20 fl oz/A | 7 | 12h | |
Alternaria leaf blight, Anthracnose, Downy mildew, Suppression of Phytophthora blight | famoxadone + cymoxanil (Tanos) | 11+27 | 8 (to 10) oz/A | 3 | 12h | |
Botrytis gray mold | fenhexamid (Decree) | 17 | 1.5 lb/A or 1 to 1.5 lb/A if tank mixed | 0 | 12h | |
Alternaria leaf spot, Anthracnose, Cercospora leaf spot, Downy mildew, Gummy stem blight, Scab | mancozeb (various) | M3 | See label | See label | See label | |
Alternaria leaf spot, Cercospora leaf spot, Downy mildew, Phytophthora rot | mancozeb + zoxamide (Gavel) | M3+22 | 1.4 to 2 lb/A | 5 | 48h | |
Suppression of Downy mildew, Suppression of Phytophthora blight | mandipropamid (Revus) | 40 | 8 fl oz/A | 0 | 4h | |
Alternaria leaf spot, Botrytis, Gummy stem blight, Powdery mildew, Sclerotinia stem rot | penthiopyrad (Fontelis) | 7 | 0.375 to 0.5 fl oz/gal to treat 1,360 sq ft | 1 | 12h | |
Botrytis gray mold, Corynespora leaf spot, Early blight, Gummy stem blight, Powdery mildew, Scab | polyoxin D zinc salt (Affirm, OSO) | 19 |
See label |
0 | 4h | |
Powdery mildew | potassium bicarbonate (Milstop) | NC | 1.25 to 5.0 lb/100 gal | 0 | 1h | |
cyflufenamid (Torino) | U6 | 3.4 oz/A | 0 | 4h | ||
sulfur (various) | M2 | See label | See label | See label | ||
triflumizole (Procure, Terraguard) | 3 | See label | 1 | 12h | ||
Alternaria leaf spot, Anthracnose, Cercospora leaf spot, Downy mildew, Gummy stem blight, Scab, Target spot | potassium phosphite + chlorothalonil (Catamaran) | 33+M5 | 4 pt/A or 6 pt/A depending on disease | 1 | 12h | |
Damping off and root rots (Phytophthora spp. and Pythium spp.) | propamocarb hydrochloride (Previcur Flex) | 28 | See label | 2 | 12h | |
Lettuce | Downy mildew | cymoxanil (Curzate) | 27 | See label | See label |
12h |
Alternaria leaf spot, Botrytis gray mold, Sclerotinia rot, Basal rot, Septoria leaf spot, Suppression of Powdery mildew | cyprodinil + fludioxinil (Switch) | 9+12 | 11 to 14 fl oz/A | 0 | 12h | |
Botrytis gray mold, Drop rot, Sclerotinia minor, Watery soft rot | dicloran (Botran) | 14 | See label | 14 | 12h | |
Downy mildew, White rust | famoxadone + cymoxanil (Tanos) | 11+27 | 8 to 10 oz/A | 1 | 12h | |
Botrytis gray mold | fenhexamid (Decree) | 17 | See label | 3 | 12h | |
Anthracnose, Downy mildew | manxozeb (various) | M3 | See label | See label | See label | |
Downy mildew | mandipropamid (Micora, Revus) | 40 | See label | See label | 4h | |
Alternaria leaf spot, Botrytis gray mold, Cercospora leaf spot, Powdery mildew, Septoria leaf spot | penthiopyrad (Fontelis) | 7 | 14 to 24 fl oz/A | 3 | 12h | |
Alternaria leaf spot, Anthracnose, Botrytis, Cercospora leaf spot, Powdery mildew | potassium bicarbonate (Milstop) | NC | 1.25 to 5.0 lb/A | 0 | 1h | |
Damping off root rots (Phytophthora and Pythium spp.) | propamocarb hydrochloride (Previcur Flex) | 28 | See label | 2 | 12h | |
Powdery mildew | sulfur (various) | M2 | See label | See label | See label | |
Alternaria leaf spot/black spot, Powdery mildew | triflumizole (Procure) | 3 | 6 to 8 fl oz/A | 0 | 12h | |
Tomato (after transplanting in a greenhouse) | Anthracnose, Black mold, Early blight, Gray leaf spot, Powdery mildew, Septoria leaf spot, Target spot | azoxystrobin + difenoconazole (Quadris Top) | 11+9 | 8 fl oz/A | 0 | 12h |
Anthracnose, Bacterial speck and spot, Early blight, Gray leaf mold, Late blight, Septoria leaf spot | copper, fixed (various) | M1 | See label | See label | See label | |
Late blight, Phytophthora blight | cyazofamid (Ranman) | 21 | See label | 0 | 12h | |
Late blight | cymoxanil (Curzate) | 27 | 3.2 to 5.0 oz/A | 3 | 12h | |
mefenoxam + mancozeb (Ridomil Gold) | 4+M3 | 2.5 lb/A | 5 | 48h | ||
Early blight, Botrytis gray mold, Powdery mildew | cyprodinil + fludioxinil (Switch) | 9+12 | 11 to 14 oz/A | 3 | 12h | |
Anthracnose, Black mold, Botrytis gray mold, Early blight, Gray leaf spot, Leaf mold, Powdery mildew, Septoria leaf spot, Target spot | difenoconazole + cyprodinil (Inspire Super) | 3+9 | 16 to 20 fl oz/A | 0 | 12h | |
Phytophthora and Pythium root rots | etridiazole (Terramaster) | 14 | 6 to 7 fl oz/A | 3 | 12h | |
fosetyl-Al (various) | 33 | 2.5 to 5 lb/A | 14 | 12h | ||
Anthracnose, Early blight, Late blight, Leaf mold, Septoria leaf spot, Suppression of: Bacterial canker, spot, and speck; Buckeye rot | famoxadone + cymoxanil (Tanos) | 11+27 | See label | 3 | 12h | |
Botrytis gray mold | fenhexamid (Decree) | 17 | See label | 0 | 12h | |
Anthracnose, Bacterial speck and spot, Early blight, Gray leaf spot, Late blight, Leaf mold, Septoria leaf spot | mancozeb (various) | M3 | See label | See label | See label | |
mancozeb + copper (ManKocide) | M1+M3 | See label | 5 | 48h | ||
mancozeb + zoxamide (Gavel) | M3+22 | 1.5 to 2 lb/A | 5 | 48h | ||
Anthracnose, Black mold, Early blight, Gray leaf spot, Late blight, Leaf mold, Powdery mildew, Septoria leaf spot, Target spot | mandipropamid + difenoconazole (Revus Top) | 3+40 | 5.5 to 7 fl oz/A | 1 | 12h | |
Powdery mildew, Southern blight | myclobutanil (Rally) | 3 | 2.5 to 4 oz/A | 0 | 48h | |
Anthracnose, Black mold, Botrytis gray mold, Early blight, Gray leaf spot, Leaf mold, Basal stem rot, Powdery mildew, Septoria leaf spot, Target spot, Suppression of Anthracnose | penthiopyrad (Fontelis) | 7 | 0.5 to 0.75 fl oz/gal per 1,360 sq ft | 0 | 12h | |
Phytophthora root rot | phosphorous acid (various) | 33 | See label | See label | See label | |
Botrytis rot, Early blight, Powdery mildew, Suppression of Anthracnose | polyoxin D zinc salt (Affirm, OSO) | 19 | See label | 0 | 4h | |
Early blight, Gray leaf mold, Gray leaf spot, Late blight, Septoria leaf spot, Target spot | potassium phosphite + chlorothalonil (Catamaran) | 33+M5 | See label | 0 | 12h | |
Damping off and root rots (Pythium and Phytophthora spp.) | propamocarb hydrochloride (Previcur Flex) | 28 | See label | 5 | 12h | |
Botrytis gray mold | pyraclostrobin + boscalid (Pageant Intrinsic) | 7+11 | 23 oz/A | 0 |
12h |
|
Botrytis gray mold, Early blight | pyrimethanil (Scala) | 9 | 7 fl oz/A | 1 | 12h | |
Powdery mildew | sulfur (various) | M2 | See label | See label | See label | |
triflumizole (Terraguard) | 3 | 2 to 4 fl oz/100 gal | 1 | 12h | ||
Anthracnose, Early blight, Septoria leaf spot | zinc dimethyl-dithio-carbamate (Ziram) | M3 | 3 to 4 lb/A | 7 | 48h |
Note: This information was adapted from the Southeastern Vegetable Handbook in 2017.
Other Links
For assistance with a specific problem, contact your local N.C. Cooperative Extension center.
Acknowledgements
Charles Averre, S. F. Jenkins, Paul B. Shoemaker
Note on Recommendations
Recommendations of specific chemicals are based upon information on the manufacturer's label and performance in a limited number of trials. Because environmental conditions and methods of application by growers may vary widely, performance of the chemical will not always conform to the safety and pest control standards indicated by experimental data. All recommendations for pesticide use were legal at the time of publication, but the status of registration and use patterns are subject to change by actions of state and federal regulatory agencies.
Publication date: Dec. 6, 2017
The use of brand names in this publication does not imply endorsement by NC State University or N.C. A&T State University of the products or services named nor discrimination against similar products or services not mentioned.
Recommendations for the use of agricultural chemicals are included in this publication as a convenience to the reader. The use of brand names and any mention or listing of commercial products or services in this publication does not imply endorsement by NC State University or N.C. A&T State University nor discrimination against similar products or services not mentioned. Individuals who use agricultural chemicals are responsible for ensuring that the intended use complies with current regulations and conforms to the product label. Be sure to obtain current information about usage regulations and examine a current product label before applying any chemical. For assistance, contact your local N.C. Cooperative Extension county center.
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