SUSCEPTIBILITY OF RED FRUITED PEAR CULTIVARS TO FIRE BLIGHT

Red-fruited pear cultivars were evaluated for relative susceptibility to fire blight by inoculation under greenhouse and field conditions.
Other pear cultivars, from which red sports arose or which were used in controlled crosses in red cultivar development were also evaluated.
Red-fruited cultivars grown commercially in southern Oregon were observed for severity of fire blight under conditions of natural infection, and for horticultural characteristics which could affect fire blight incidence.
The epiphytotic severity observed in commercial orchards appeared to correspond most closely to the percent of shoot length blighted after 2 weeks in greenhouse inoculation experiments than the percent of shoot length blighted after 4 weeks in greenhouse or field inoculation experiments.
Tree vigor and tendency to produce secondary bloom did not consistently correspond with epiphytotic severity. ‘Rogue Red’ and ‘Regal Red Comice’ showed the most resistance to fire blight among red-skinned cultivars, while ‘Canal Red’, ‘Sensation Red Bartlett’, ‘Rosired Bartlett’, and ‘Red Clapp’s Favorite’ were the most susceptible.

IV International Workshop on Fire Blight

D. Sugar, P. Buskirk, T. Zwet, R. Bell

https://doi.org/10.17660/ActaHortic.1987.217.49