Bull's-eye Rot
Neofabraea malicorticis (anamorph: Cryptosporiopsis curvispora), N
0 host plants · Fungal
Last updated
Bulls-eye rot appears as concentric rings on fruit, resembling a target or bull's-eye pattern. You see brown spots develop during storage or final ripening stages. The fungal disease affects fruit quality and marketability significantly. Manage through good sanitation, proper harvesting techniques, and appropriate storage conditions.
Reduce moisture around affected tissue by improving drainage and air circulation. Remove rotted material cleanly and dispose of it away from the planting area. Avoid wounding healthy tissue during cleanup, as fresh wounds create new entry points. If the problem keeps returning, evaluate whether the site is too wet or poorly drained for the species you are growing.
Quick Reference
Management
Fall (August-October) for fruit infection; spring (March-May) for canker development and shoot infection. Peak fall vulnerability: 8 weeks pre-harvest. source: PNW Plant Disease Management Handbook
Fall: cool wet conditions (50-60°F) with rain; fruit most vulnerable 8 weeks pre-harvest. Spring: wet conditions during canker development and sporulation. High-rainfall areas west of Cascade Range at greatest risk. source: PNW Plant Disease Management Handbook
Cultural Controls
- Aggressive scouting for and removal of cankers is the key to long-term control. PNW Plant Disease Management Handbook
- Prune out cankers in dry weather before fall rains. Use a pruning knife to cut several inches above and below canker margin. Remove all brown strands (infected tissue) in sapwood. Sterilize knife after each canker removal. PNW Plant Disease Management Handbook
- Trees heavily infested (4+ cankers on majority of branches and trunk) should be removed and burned. PNW Plant Disease Management Handbook
- Establish new plantings with clean stock free of visible cankers. Locate new orchards as far as possible from older orchards with existing cankers. PNW Plant Disease Management Handbook
- Scout new orchards regularly; early detection aids overall control. PNW Plant Disease Management Handbook
- All apple cultivars are susceptible. Avoid highly susceptible cultivars: 'Akane', 'Baldwin', 'Chehalis', 'Elstar', 'Empire', 'Gala', 'Gravenstein', 'Melrose', 'Sinta', 'Spartan'. PNW Plant Disease Management Handbook
Bull's-eye rot is severe in high-rainfall apple-growing areas west of the Cascade Range and coastal British Columbia. N. malicorticis is the most common species in western Washington; N. vagabunda and N. kienholzii have also been confirmed here. Maritime moisture and persistent fall rain drive spore dispersal from limb cankers to maturing fruit. The disease is less significant in drier east-side growing regions.
Sources & References
Primary: PNW Plant Disease Management Handbook
- PNW Plant Disease Management Handbook (Anthracnose/Bull's-eye Rot)
- PNW Plant Disease Management Handbook (Perennial Canker/Bull's-eye Rot)
- PNW Plant Disease Management Handbook (Bull's-eye Rot)
- WSU Tree Fruit (Apple Anthracnose)
- WSU Tree Fruit (Bull's Eye Rot)
- WSU HortSense (Anthracnose)
- WSU HortSense (Perennial Canker)
- WSU Extension FS297E (Anthracnose Canker IMP for Home Gardeners)