SCANNING ELECTRON-MICROSCOPY OF HYPHAL INTERACTION BETWEEN STREPTOMYCES-GRISEOVIRIDIS AND SOME PLANT PATHOGENIC FUNGI

The interaction between Streptomyces griseoviridis and the pathogens A lternaria brassicicola, Botrytis cinerea, Fusarium oxysporum, Mycocent rospora acerina, Rhizoctonia solani and Sclerotinia sclerotiorum was s tudied by SEM both on autoclaved seeds and living seedlings of turnip rape and carrot and the fungi Phomopsis sclerotioides and Pythium ulti mum on cucumber seedlings. The samples were prepared by the standard m ethod for examination by scanning electron microscope. The hyperparasi tism of S. griseoviridis was clearly shown. S. griseoviridis tightly w ound around Alternaria conidia and Sclerotinia hyphae, eventually disi ntegrating them. It grew along the hyphae of B. cinerea, P. sclerotioi des and M. acerina, dissolving them. The hypha of F. oxysporum seemed to be slightly affected, and its conidia not at all. The hyperparasite grew only loosely on the hypha of R. solani and on the mycelium and o ogonia of Pythium which seemed not to sustain much injury.