Fire blight is a destructive bacterial disease of apples and pears that kills blossoms, shoots, limbs, and, sometimes, entire trees. The disease is generally common throughout the United States wherever apples are grown. However, outbreaks are typically very erratic, causing severe losses in some orchards in some years and little or no significant damage in others. This table shows the fire blight resistance rating of numerous apple cultivars.
|Apple cultivar||Fire blight resistance rating (z)||Apple cultivar||Fire blight resistance rating (z)|
|Arkansas Black||MR||Mollies Delicious||S|
|Fuji||HS||Rhode Island Greening||HS|
|Grimes Golden||S||Stark Bounty||MR|
|Gravenstein Holly||S||Stark Splendor||MR|
MR = moderately resistant. Control needed only with fire blight susceptible rootstocks or under high disease pressure.
S = susceptible. Control usually needed when conditions are favorable for infection.
HS = highly susceptible. Control always needed when conditions are favorable for infection. These cultivars should receive first priority when control is required.
See Fire Blight of Apple for more information.
Prepared by K. S. Yoder and A. R. Biggs from personal observations and the following sources:
van der Zwet, T., and S. V. Beer. 1995. Fire blight – Its nature, prevention, and control. USDA Agriculture Information Bulletin Number 631.
Management Guide for Low-Input Sustainable Apple Production, A publication of the USDA Northeast LISA Apple Production Project and Cornell University, Rodale Research Center, Rutgers University, University of Massachusetts, and University of Vermont. 1990. (Apple disease management section by D. A. Rosenberger, Cornell University).
A Grower’s Guide to Apple Insects and Diseases in the Southeast. 1993. Alabama Cooperative Extension Service, Auburn University, Circular ANR-838. Eds. J. R. McVay, J. F. Walgenbach, E. J. Sikora, and T. B. Sutton.