AbstractThe viability of axillary buds, and the growth and potential yield of lateral shoots at nodes of naturally infected plants were measured on excised nodes, decapitated nursery canes or on canes from fruiting plantations. Compared with lesion-free nodes, buds at infected nodes were smaller, and fewer grew when excised and forced, although the difference in growth decreased during late winter. After Feb. those buds at infected nodes capable of forced growth grew as early as and at a similar rate to those at healthy nodes. In Apr. 70% of buds at infected nodes grew compared with 94% at healthy nodes. When Malling Delight canes were decapitated above infected nodes the emergence of lateral shoots from the terminal infected node was similar to that from healthy nodes. On a range of Scottish farm sites the emergence of shoots at infected nodes in the cropping region of canes was poorer than from uninfected nodes, but substantially better at infected nodes of Glen Clova than in Malling Jewel and Malling Orion. It is suggested that Glen Clova is relatively tolerant of the 2 pathogens. The length and potential yield of laterals developing at infected nodes in the cropping region of canes in these 3 cvs. did not differ significantly from those at lesion-free nodes. There was no significant difference in growth of nodes infected by either fungus; this may indicate a common mechanism for bud suppression.