A high level of resistance to cane blight caused by B. cinerea was transferred from Rubus pileatus to the red raspberry through 3 generations of backcrossing. The strength of the resistance showed little diminution through these generations and it was therefore thought that a major gene for resistance had been transferred. However, discontinuity in the level of resistance observed was detected in plants of only 1 group of the progenies and so evidence for a major gene is lacking. The results showed the considerable influence of gene H, which confers pubescence, and emphasised that resistance must be separately assessed for pubescent and non-pubescent segregates.