Abstract

When raspberry canes were inoculated in summer with mycelium of D. applanata, resistant genotypes developed relatively small lesions which produced few fruiting bodies in the following spring. Scores of the frequency of these fruiting bodies provided the best discrimination between genotypes. Very strong resistance was found in Rubus pileatus, R. occidentalis and R. coreanus, and in hybrids of these spp. with red raspberry. Hybrids with R. crataegifolius were less resistant. Resistance was also found in Malling 1473/35, a derivative of the cultivar Chief, and in red raspberry segregates with gene H which determines cane pubescence. Both the expression of resistance and the ranking of sources for their resistance to D. applanata was similar to that reported for Botrytis cinerea.