Optimization of Growth Condition for Aquatic Fungi (Saprolegnia species) Isolated from Economically Important Freshwater Fishes

The present study was aimed to optimize the culture media, temperature, pH and sodium chloride concentration for the growth of isolated and characterized Saprolegnia strains which were isolated from four economically important infected fish specis i.e. Catla catla, Labeo rohita, Cirrhinus mrigala and Cyprinus carpio. Identification and characterization of Saprolegnia species was made by observing colony morphology and asexual reproductive organs under binocular light microscope. The result showed that the Saprolegnia sp. grown well in Sabourd’s Dextrose Agar media at optimum temperature 25oC, neutral pH 7 and 0.01% sodium chloride content. The progress of optimization is helpful to measure the occurrence, distribution, outbreaks and epidemiological survey of aquatic fungi. This susceptibility study of pathogen provides an idea to prevent before the onset/outbreak of infectious diseases and helpful in designing the bio-control agent for the Saprolegnia strains.