Field susceptibility trial of cider apple cultivars to bitter rot and black rot
- Research Date
- 2025
- Authors
- George Sundin, Kristi G. MacCready
- Priorities
- Crop Quality, Product Development, Soil Health
- Crop Categories
- Apples, Fruit
- Beverage Categories
- Cider
Fruit rots impact the supply of dessert and cider apples for Michigan’s cider industry. There is almost no information available on the susceptibility of cider apple cultivars to fruit rot infection, and little information on fungicide control. However, effective recommendationsrequire a thorough understanding of the susceptibility of cultivars to pathogens. Assessment ofdisease susceptibility of cider apple cultivars to summer fruit rots under Michigan conditions will enable growers to utilize cultivar-specific optimized spray programs for control. We determined that a few cultivars including 'Somerset Redstreak', 'Foxwhelp', 'Dabinette' and 'Nehou' were highly susceptible to bitter rot, and 'Foxwhelp', 'Yarlington Mills' and 'Nehou' were susceptible to black rot. On the plus side, the cultivars 'Liberty' and 'Tremlette Bitter' exhibited very low susceptibility to both diseases. Of fungicides tested for bitter rot control, the succinate dehydrogenase inhibitor Merivon performed the best under Michigan conditions. Our conclusion is that there are cider apple cultivars available with low susceptibility to fruit rot diseases that can be successfully grown in Michigan.