Apricot: Shothole (Coryneum blight)

Biology

Shothole is a fungal disease which attacks leaves, buds, blossoms, fruits, and twigs. Twig cankers are rare on apricot. On apricot, the fungus often infects and kills buds, which may be covered with a shiny, gummy material. Lesions on leaves and fruit are initially small purplish areas which expand into brown spots with light centers. The lesions are seldom larger than 1⁄4″ in diameter. The infected spots on leaves often die and drop out in warm weather, giving leaves a “shothole” appearance. The fungus probably overwinters on the bark and in infected buds. Spores are easily spread by water.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

• Prune and destroy dead buds and cankered twigs if present.
• Rake and destroy infected leaves.
• Avoid overhead watering.
• Space plantings and prune to provide good air circulation.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

• Apply copper fungicides or chlorothalonil products at leaf drop in late fall before heavy rains.
• Apply IMMUNOX or chlorothalonil products in spring when petals fall.
• NOTE: Bonide Fung-onil is for spring use only.
• Homeowners should not make foliar applications to trees over 10 ft tall.
• Consult a commercial pesticide applicator for treatment of trees and shrubs over 10 ft. tall.

Approved Pesticides

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.

• Bonide Fung-onil Multi-Purpose Fungicide Concentrate
  Active ingredient: chlorothalonil [EPA registration number: 60063-9-4]
• Bonide Liquid Copper Fungicide Concentrate/Organic Gardening
  Active ingredient: copper octanoate [EPA registration number: 67702-2-4]
• GardenTech Daconil Fungicide Concentrate
  Active ingredient: chlorothalonil [EPA registration number: 67572-82-71004]
• Monterey Liqui-Cop Copper Fungicidal Garden Spray
  Active ingredient: copper-ammonia complex [EPA registration number: 54705-7]
• Ortho Max Garden Disease Control Concentrate
  Active ingredient: chlorothalonil [EPA registration number: 239-2522]
• Spectracide IMMUNOX Multi-Purpose Fungicide Spray Concentrate
  Active ingredient: myclobutanil [EPA registration number: 9688-123-8845]
• This list may not include all products registered for this use.

Additional Images