Grzyby zasiedlające nasiona stewarcji pseudokameliowatej (Stewartia pseudocamellia Max.) oraz ich chorobotwórczość [Fungi isolated from Stewartia pseudocamellia Max. seeds and their pathogenesis]

The aim of studies was to determine typical composition of fungi occurring on seeds of Stewartia pseudocamellia.The studies conducted on 100 disinfected and 100 nondisinfected seeds of these plants.Isolates of Alternaria alternata, Fusarium oxysporum, Cylindrocarpon radicicola and Rhizoctonia solani were characterized by pathogenicity towards the investigated Stewartia pseudocamellia. In the laboratory experiment, 204 isolations of microorganisms were obtained that belonged to 20 species and form of fungi and bacteria. Among fungi there were both of parasite (Alternaria alternata, Botrytis cinerea, Fusarium spp., Rhizoctonia solani) and typical saprophytic (Cladosporium spp., Penicillium spp., Aspergillus spp., Epicoccum spp., Mucor spp.). The dominant fungus on seeds was Alternaria alternata. Among the investigated isolates only one isolate (R4) Rhizoctonia solani, was strongly pathogenic, isolates (A1) Alternaria alternata were weakly pathogenic to seedlings of Stewartia pseudocamellia