Susceptibility of highbush blueberry (Vaccinium corymbosum L.) cultivars to Godronia canker (Godronia cassandrae f. sp vaccinii) in Norway

Godronia canker, caused by the fungus Godronia cassandrae f. sp. vaccinii, was detected for the first time on highbush blueberry (Vaccinium corymbosum ) in Norway in 1995, and has caused severe stem wilting and dieback of youn g bushes. The disease was investigated over five years (1995-1999) in two e xperimental plantings, and in a survey carried out in 51 highbush blueberry plantings in Norway during the summer of 1998. Altogether, 31 cultivars we re included in the investigations. None of the cultivars were completely re sistant, but there were great differences in susceptibility. 'Goldtraube' a nd 'Hardyblue' were the most resistant cultivars, but 'Bluetta' and 'Patrio t' also seemed to have low susceptibility to Godronia canker. 'Ama', 'Heerm a' and 'Spartan' had low to moderate susceptibility, 'Berkeley' 'Bluecrop', 'Duke' and 'Ivanhoe' had moderate to high susceptibility, and 'Blueray', 'C ollins: 'Earliblue', and 'Jersey' were most susceptible. The latter four sh ould not be recommended for highbush blueberry production in the cool, wet climate of Norway.