Differences in susceptibility of the nine Fagaceae species to Raffaelea quercivora

Abstract

Seedlings of nine Fagaceae species (Quercus variabilis, Q. dentata, Q. aliena, Castanea crenata, Q. acuta, Q. gilva, Q. myrsinifolia, Q. sessilifolia, Castanopsis cuspidata) native to Japan were inoculated with Raffaelea quercivora, a pathogenic fungus of Japanese oak wilt, in order to assess their susceptibility to this pathogen. The seedlings of these species were compared with species susceptible (Q. crispula and Q. serrata) and weakly susceptible (Q. glauca and Castanopsis sieboldii) to the fungus. The relative areas of non-conducting sapwood on stem cross-sections in Q. variabilis, Q. dentata, C. crenata and Q. aliena was significantly larger than that in Q. glauca and C. sieboldii, and was similar to Q. crispula and Q. serrata. These results indicate that Q. variabilis, Q. dentata, C. crenata and Q. aliena are susceptible to R. quercivora.