Neonectria ramulariae causing seed rot of Fagus crenata in Japan
In Japan, during a survey of seed diseases of Fagus crenata (Japanese beech), a new fungal disease was frequently observed in a beech forest in Tazawako (Akita prefecture, Northern Honshu). Many rotting seeds were observed on the ground (split seed coats and brown cotyledons). The causal agent of this seed rot was identified as Neonectria ramulariae (anamorph: Cylindrocarpon obtusiusculum). This is the first time that this soil-borne fungus is reported to cause a disease on seeds of F. crenata.
Hirooka Y, Ichihara Y, Masuya H, Kubono T (2012) Seed rot, a new disease of beech tree caused by Neonectria ramulariae (anamorph: Cylindrocarpon obtusiusculum). Journal of Phytopathology 160(9), 504-506.