Resistant rootstocks are key to surviving fireblight
Courtesy Herb Aldwinckle
Within the next two years, Cornell University plant pathologist Dr. Herb Aldwinckle hopes scientists and tree fruit nurseries will have solved the problems of propagating Cornell's Geneva 41 rootstock, which is resistant to fireblight and replant disease. It would then be a viable alternative to the Malling 9 rootstock, which is susceptible to fireblight. Right now, G.41 is in short supply because nurseries are having trouble propagating it in stoolbeds.
The Gala orchard pictured was planted in 2005 and shows varying effects of fireblight.
Look for an article in the February 15 Good Fruit Grower that contains more information about G. 41 and other disease-resistant rootstocks.