Host range of Plasmodiophora brassicae in North Dakota

Abstract

Plasmodiophora brassicae causes clubroot on brassica crops and is a new emerging disease on rapeseed in North
Dakota. A two-year study was conducted to document the host range and symptomology on various brassica hosts to
P. brassicae infections in field conditions. The results indicated that out of the 13 Brassica hosts tested, 12 of them
developed ellipsoidal galls on roots exhibiting the clubroot symptomology with a disease index (DI) ranging from 41 to
100%. False flax/ camelina (Camelina sativa) showed the least susceptibility among the brassica hosts tested.
Symptomology of clubroot on various brassica hosts will serve as a pictorial guide in the future to educate growers and
in choosing non-brassica cover crops in clubroot infected fields.