Isozyme Analysis of Ganoderma Isolates from Infected Oil Palm and Coconut Stumps in Malaysia

Seventy-three Ganoderma isolates from infected oil palm and coconut stumps were obtained from basidiomata collected from various locations in Malaysia. The isozymes of these isolates were analysed using polyacrylamide gel electrophoresis (PAGE) with the objective of determining the relatedness between Ganoderma isolates from infected oil palm and coconut stumps. A total of 25 enzyme systems were studied but only 16 were successfully typed. These were acid phosphatase (ACP), alkaline phosphatase (AKP), alcohol dehydrogenase (ADH), aconitase (ACO), hydroxy-butyrate dehydrogenase (HBDH), glutamate oxaloacetate transaminase (GOT), isocitrate dehydrogenase (IDH), hexokinase (HK), malic enzyme (ME), malate dehydrogenase (MDH), peroxidase (PRX), phosphoglucomutase (PGM), shikimate dehydrogenase (SKDH), leucine amino peptidase (LAP), peptidase D (PEP D) and esterase (ES). Only 3 isozyme systems, ADH, GOT and PRX showed monomorphic patterns whereas the other 13 showed polymorphic patterns. There were no distinct isozyme bands or patterns that could differentiate between Ganoderma isolates from infected oil palm and coconut stumps as variations occurred between and within the isolates of the two groups of Ganoderma. A dendrogram based on the cluster analysis of the isozyme data demonstrated that Ganoderma isolates from infected oil palm and coconut stumps showed high levels of similarity and were clustered together which indicating close relatedness. The finding that Ganoderma isolates from infected oil palm and coconut stumps are closely related would have important implications in the formulation of methods for disease management.