Root Rot of Macadamia Caused by Ganoderma lucidum and Kretzschmaria clavus in Taiwan

Abstract

About 10% of macadamia trees at Puli showed various degrees of decline due to extensive root decay. The decay also extended to the main trunk and eventually caused the death of tree s. Infected tissues of most diseased trees turned soft. This was found to be caused by Ganoderma lucidum. Other declining trees were resulted from invasion by Kretzschmaria clavus which formed black lines on infected tissues. Ganoderma lucidum grew faster and appeared to thrive at relatively high temperature in comparsion with K. clavus. 在埔里地區，由於根腐病之蔓延，約有10％之澳洲胡桃顯現不同程度之枯萎。而且這種組織腐敗擴展至主幹，最後引起樹木死亡。 大部份染病的澳洲胡桃組織軟化，證實系由靈芝Ganodorma lucidum感染所致。另有部份衰敗的植株，則因Kretzschmaria clavus侵入之故，病菌並在木材上形成黑色線紋，但組織並不軟化。與K. clavus相較，G. lucidum生長較快速，且偏好高溫。