In Vitro Inhibition of Growth in Saprolegnia sp. Isolated from the Eggs of Persian Sturgeon Acipenser persicus (Pisces: Acipenseriformes) by Pseudomonas aeroginosa (PTCC:1430)

Saprolegnia is one of the most important agents decreasing the eggs survival rate in sturgeon hatcheries. There are some chemical substances for controlling the fungal infection of eggs. In this study, an attempt was made to introduce a germ negative bacterium, Pseudomonas aeroginosa (PTCC1430)(Persian Type Culture Collection) as a biocontrol ling agent of water mold. Saprolegnia was isolated from the eggs of some infected Persian sturgeon, Acipenser persicus in a sturgeon hatchery and then was purified. P. aeroginosa was cultured in Potato dextrose Agar (PDB) media and then was prepared in 5 concentrations (103,104,105,106and107cfu.ml-1) while challenging with fungi in petri dishes under laboratory conditions. The results showed that by increasing the concentration of the bacteria in plates, hyphal growth of the fungi was reduced. The highest concentration of P. aeroginosa concentration (107) roughly stopped the fungi growth and the Minimum Inhibitory Concentration (MIC) was 104cfu.m-l. Results in this study implied the potential of P. aeroginosa (PTCC1430) as a biological agent in controlling saprolegniosis.