淡水魚類の水カビ病原因菌の生物学的性状による分類の試み

抄録

　The identification of water moulds of the family Saprolegniaceae has been based on their asexual and sexual characteristics. In this study, we attempted to classify the three genera Saprolegnia, Achlya and Aphanomyces in the Saprolegniaceae from some of their biological characteristics. The optimal temperatures for growth were 20-25°C, 30-35°C and 25-30°C for Saprolegnia, Achlya and Aphanomyces, respectively. The three genera also differed in their sensitivities to malachite green, NaCl, K₂HPO₄, sorbose and Polyphenon-100^R. The strains tested were decreasingly sensitive of NaCl and K₂HPO₄ in the order of Aphanomyces, Achlya and Saprolegnia, and to malachite green, Polyphenon-100^R and sorbose in the order of Apanomyces, Saprolegnia and Achlya. From the sensitivity tests of Aphanomyces to Polyphenon-100^R and sorbose, the pathogenic strain A. piscicida could be distinguished from the saprophytic strains. The three genera in the Saprolegniacease and some species in these genera could thus be classified on the basis of certain biological characteristics. Biological tests might thus be applicable for the classification of fungi belonging to certain genera of the Saprolegniaceae.