Cause Passalora capsicicola (syn. Cercospora capsici), a fungus that overwinters on dead plant parts.
Symptoms Round or oblong leaf spots occur, which at first are water-soaked and up to 0.5 inch in diameter, but later turn tan with a dark marginal ring. Centers often drop out as the spots age. Spots develop on stems and petioles and, when numerous, leaves turn yellow and may drop or wilt. Defoliation is often serious, exposing pepper fruit to sunburn.
Cultural control
- Practice at least a two-year rotation between solanaceous crops, but three-year rotations are better for the management of other diseases.
- Use pathogen-free seed.
- Inspect transplants and discard diseased plants before transplanting.
- Use drip rather than overhead irrigation.
- Destroy diseased plants by soil incorporation.
Chemical control
- Aprovia Top (Group 7 + 3) at 10.5 to 13.5 fl oz/A on 7- to 10-day intervals. Do not make more than two (2) sequential applications before alternating to a labeled fungicide with a different mode of action. Preharvest interval is 0 days. 12-hr reentry.
- Chlorothalonil (Group M5) formulations are labeled.
- Bravo Weather Stik at 1.5 pints/A or Bravo Ultrex at 1.4 lb/A on 7- to 10-day intervals. Preharvest interval is 3 days. 12-hr reentry.
- Echo 720 at 1.5 pints/A on 7- to 10-day intervals. Preharvest interval is 3 days. 12-hr reentry.
- Copper (Group M1) applications during wet periods may help but avoid build-up of copper in the soil.
- Badge SC at 0.75 to 2.25 pints/A and 0.5 to 2 Tbsp/1,000 sq ft in greenhouses on 3- to 10-day intervals. Preharvest interval is 0 days. 24-hr reentry for greenhouse use; 48-hr reentry for all other applications.
- Champ Formula 2 at 1.33 to 2 pints/A. 48-hr reentry.
- Cueva at 0.5 to 2 gal100 gal water on 7- to 10-day intervals. May be applied on the day of harvest. 4-hr reentry. O
- Cuprofix Ultra 40 Disperss at 1.25 to 3 lb/A on 5- to 10-day intervals. 48-hr reentry.
- Kocide 2000 at 1.5 to 2.25 lb/A or Kocide 3000 at 0.75 to 1.25 lb/A on 7- to 10-day intervals. 48-hr reentry.
- Liqui-Cop at 1.5 to 3 teaspoons/gal water. H
- Previsto at 1 to 2 quarts/A on 5- to 10-day intervals. 48-hr reentry. O
- Demethylation-inhibiting (DMI) fungicides (Group 3) are registered for use. Alternate or tank-mix with a non-Group 3 fungicide for resistance management.
- Rhyme at 7 fl oz/A on 7- to 14-day intervals. Preharvest interval is 0 days. 12-hr reentry.
- Topguard at 14 fl oz/A on 7-day intervals. Preharvest interval is 0 days. 12-hr reentry.
- Orondis Opti (Group M5 + 49) at 1.75 to 2.5 pints/A on 7- to 10-day intervals. Do not apply more than two (2) sequential applications. Preharvest interval is 3 days. 12-hr reentry.
- Strobilurin fungicides (Group 11) are labeled for use. Do not make more than one (1) application of a Group 11 fungicide before alternating to a labeled fungicide with a different mode of action.
- Dexter Max (Group M3 + 11) at 1.7 to 2.25 lb/A on 7- to 10-day intervals. Preharvest interval is 7 days. 24-hr reentry.
- Quadris Top (Group 3 + 11) at 8 to 14 fl oz/A on 7- to 10-day intervals. May be applied the day of harvest. 12-hr reentry.
- Trilogy at 0.5% to 1%. Not labeled for use in Oregon. Do not use above 90°F or when plants are under heat or moisture stress. Do not use when foliage is wet as good coverage is essential. Poor control as a stand-alone product. 4-hr reentry. O