Studies on the host range of Sirococcus clavigignenti-juglandacearum
In North America, butternut (Juglans cinerea) is severely affected by the fungus Sirococcus clavigignenti-juglandacearum (EPPO A1 List). So far J. cinerea is the only species where mortality has been reported, although natural infections have also been observed on hartnut (J. ailantifolia var.cordiformis). Studies were carried out in the USA to determine the susceptibility of Juglans species and hybrids, and of various other hardwood species to S. clavigignenti-juglandacearum to identify potential host plants in forests and nurseries. Artificial inoculations indicated that, although S. clavigignenti-juglandacearum was not causing lethal cankers, it could colonize and develop on Carya cordiformis, C. illinoensis, C. ovata, Prunus serotina, Quercus alba, Q. macrocarpa, Q. rubra, Q. velutina, Castanea dentata, C. mollissima, Corylus americana and C. cornuta. Several commercial cultivars of Juglans regia were found moderately to highly susceptible to S. clavigignenti-juglandacearum. Although J. cinerea is the only species killed by the fungus, this study suggests that other hardwood species, including J. regia (cultivated in the EPPO region), could be infected by the fungus. However, these artificial inoculation studies need to be confirmed by further field trials and observations.
Ostry ME, Moore M (2007) Natural and experimental host range of Sirococcus clavigignenti-juglandacearum. Plant Disease 91(5), 581-584.