Fire Blight Susceptibility of Fruiting Trees of Some Apple Rootstock Clones1
in HortScienceAbstract
After a severe fire blight epiphytotic, fruiting trees of rootstock cultivars were scored for kill of fruit spurs, for lesion extension, and total tree damage. Spur infections were heaviest on ‘M 9’, ‘M 12’, ‘M 16’, ‘M 25’, ‘M 26’ and ‘Rotyp’. Damage to ‘M 9’ and ‘M 26’ trees was especially severe. Least affected were ‘M 2’, ‘M 7’, ‘M 15’ and a Malus prunifolia selection, PI 286613. Intermediate susceptibility was indicated for ‘M 27’ and a red-leaved introduction from the USSR, PI 274842.
Contributor Notes
Received for publication January 22, 1973. Approved by the Director of the New York State Agricultural Experiment Station for publication as Journal Paper No. 2003.
Department of Pomology and Viticulture.
Department of Plant Pathology.
