PHYSIOLOGICAL ADAPTATION OF AN APHANOMYCES-ASTACI STRAIN ISOLATED FROM THE FRESH-WATER CRAYFISH PROCAMBARUS-CLARKII

Physiological, epidemiological and genetical properties of an Aphanomy ces astaci strain (Pc) isolated from the warm water crayfish, Procamba rus clarkii, were compared to other A. astaci strains isolated from th e cold water crayfish Astacus astacus, Astacus leptodactylus and Pacif astacus leniusculus. Morphology, virulence at 10 degrees C and several physiological characters were similar to the rest of A. astaci strain s used for comparison. However, the strain Pc was able to grow faster and release zoospores at higher temperatures. This means that the Pc s train is virulent towards crayfish at higher temperatures than any pre viously investigated strains. The application of RAPD-PCR demonstrated that this isolate is genetically separated from all other described s trains.