In vitro interaction between Phlebiopsis sp. and Ganoderma philippii isolates

Ganoderma philippii causes root-rot disease in a wide range of commercial perennial woody crops such as rubber and tropical acacias. In terms of productivity loss, the disease is considered as the most economically damaging disease of Acacia mangium. Many strategies to manage root rot have been developed and applied, including application of biological control which has focused on species and strains of the ascomycete genus Trichoderma. This research aimed to test the potential of a wood-rotting basidiomycete as a biocontrol agent for root rot caused by Ganoderma philippii. This basidiomycete was isolated from a Eucalyptus pellita stump in a coppicing trial in Riau province, central Sumatra. DNA sequence analysis indicated that this isolate is most likely a Phlebiopsis sp. In vitro tests and microscopic morphological description of mycelial interactions between the Phlebiopsis and G. philippii isolates showed a mycoparasitic reaction. This result offered an alternative potential fungal isolate for root-rot management in Indonesia as Phlebiopsis gigantea is already successfully used as a biocontrol agent for managing root rot caused by Heterobasidion annosum throughout pine forests in Europe and North America.