Raspberry root rot is a serious soil-borne disease caused by the fungal infection of raspberry roots, crowns and the bases of young and old canes by Phytophthora. Several Phytophthora species are known to infect red raspberry, but the most prevalent pathogen in serious disease outbreaks is Phytophthora fragariae var rubi, which is very closely related to the fungus causing strawberry red core.
Death of lateral shoots due to root rot in fruiting cane
and failure of spawn growth
Raspberry root rot only became apparent as a problem for Scottish raspberry producers in the mid-1980's, but with its rapid spread and severity across Europe work began at The James Hutton Institute on this major disease problem facing the soft fruit industry. Root rot is now the most destructive disease of raspberries in the UK. All parts of the plant below or at ground level can be infected and affected canes die in the first year of growth or their buds fail to emerge at the start of the second growing season. Alternatively, emerged laterals wilt and die at any time from emergence until late in fruiting.
Root rot lesion at base of primocane