PREDOMINANT EPIPHYTIC BACTERIA ON DAMAGED POLYMNIA-SONCHIFOLIA LEAVES, AND THEIR METABOLIC PROPERTIES ON PHENOLICS OF PLANT-ORIGIN

The epiphytic microfloral population on damaged and nondamaged leaf su rfaces of Polymnia sonchifolia (Compositae) was examined, and metaboli c properties of microbes predominant on the damaged leaves were studie d. On the damaged leaf surface, some epiphytic Gram-negative bacteria able to metabolize phenolic compounds of plant origin were highly asce ndant. The most dominant bacterium, Pseudomonas viridiflava had a high activity of peroxidase on pyrocatechol, while the second major bacter ium Phyllobacterium myrsinacearum, produced 4-hydroxycinnamate decarbo xylase. Thus, it was likely that epiphytic bacteria predominant on dam aged leaves can metabolize plant phenolics. These epiphytic bacteria f requently formed mixed colonies during their isolation, and the mixed colonies were retarded in their growing rate compared with single colo nies of each.