Abstract

Wilt and dieback of raspberry have increased during the past few years in the main raspberry districts of Norway, while yields have decreased. In 1988, 60 raspberry fields with growth problems were investigated for pathogens. Symptoms of Phytophthora root rot were found in 11 of the fields. Oospores were found in rotted roots from seven of the fields, including a clonal trial at the Njøs Research Station, planted in 1984. Phytophthora megasperma was isolated from material from the trial.