EFFECTS OF STREPTOMYCES SP. ON GROWTH OF RUBBERWOOD SAPSTAIN FUNGUS LASIODIPLODIA THEOBROMAE

An actinomycete isolated from the soil, identified as Streptomyces sp. SA18, was found to be an effective antagonist against the fungus Lasiodiplodia theobromae that caused sapstain on rubberwood. One of the antagonistic factors responsible for this inhibitory effect was identified as chitinase enzyme production, which degraded the chitin of fungal cell wall to N-acetyl D-glucosamine. In the chitin agar plate inoculated with Streptomyces sp. SA18, the dye bound with stable chitin and fluoresced under ultra violet light. On the contrary, chitin-free portions appeared dark indicating degradation of chitin by chitinase enzyme produced by Streptomyces sp. SA18.