Disease Control

Leaf Blight (Cercospora or Septoria)

NOTE:  For the materials listed below, one product trade name and formulation is provided for each active ingredient (common name) as an example of rates, days to harvest (dh), REI, and special instructions. In many cases there are other products available with the same active ingredient. Please see Table 20 and Alphabetical Listing by Trade Name for more information on products with the same active ingredients.

Use certified, disease-free seed or treat seed with hot water or fungicides.  Practice careful sanitation in transplant greenhouses or rotate ground seedbeds.  Irrigate early in the day to allow foliage to dry quickly.  Use wider plant spacing and/or raised beds to improve air circulation.  Plant resistant or tolerant varieties where available.  Apply fungicides based upon a disease forecasting system.

azoxystrobin (Quadris): 9.0-15.5 fl oz/A. (0 dh, REI 4h, Group 11). Do not apply more than one application before alternating with a non-Group 11 fungicide.

chlorothalonil (Bravo Ultrex): 1.8-2.7 lb/A. (7 dh, REI 12h, Group M5). Repeat at 7 day intervals as needed.  

 copper sulfate (Basic Copper 50 W HB). 0.5-2 lb/A. ( 0 dh, REI 48h, Group M1). Do not apply in a spray solution having a pH less than 6.5.

propiconazole (PropiMax EC): 4 fl oz/A. ( 7dh, REI 24h, Group 3). 

trifloxystrobin (Flint): 2.0-3.0 oz/A. (7 dh, REI 12h, Group 11). Do not make more than one application before alternating with a non-Group 11 fungicide. Do not alternate with Quadris.

Basal Stalk Rot (Rhizoctonia)

A two-year rotation is recommended to prevent buildup of disease-causing organisms.  Avoid crops such as alfalfa and legume cover crops which can increase disease risk.  Avoid cultivating late in the season.  Maintain storage conditions at 50°F .

azoxystrobin (Quandris):  0.4 to 0.8 fl oz/1,000 row feet (0 dh, REI 4h, Group 11) (see label for clarification).  Apply in a 7" band in-furrow or shortly after emergence.  After emergence, direct application to stem.