Abstract
This study investigated the incidence of Clitocybe root rot of cherry trees in Matsue-Jozan Park between March 2002 and March 2010. Of the trees studied, 63% were identified as diseased, and 37% were dead. This severe damage may be attributable to the application of wood chips to the study trees. Somatic incompatibility tests were used to determine the genet distribution of the isolates obtained from infected or dead trees. The 70 isolates obtained were classified into 10 genets. Nine genets were found in 1∼11 trees. The remaining genet was found in 27 trees, of which 25 were widely separated in a 50×75 m plot. Eleven saplings were paired with and planted near dead trees and rapidly died within 2∼4 years after planting; the isolates obtained from these saplings were the same as those obtained from the dead trees located nearby. These results suggest that the pathogen was transmitted via air-borne basidiospores and spread clonally underground in the park. The isolates from trees separated by 270 m from each other were identified as belonging to the same genet, suggesting that inocula of the pathogen were transmitted between the trees.
