Biological control of bloom algae in the southern of Caspian Sea

In recent years the incidence of algal blooms caused by Nodularia to become one of the serious problems and is threated life of aquatic organisms in the southern Caspian Sea. Nodularia is a Blue-green algae (cyanobacteria group) and due to production of nodularin toxin is importance. In this study, the first, three species of Pseudomonas including aeruginosa, putida and fluorescens were isolated from Tajan river estuary and identified using biochemical tests and compared to standard species. The trend of Nodularia spumigena biomass (log 5) and pseudomonas species (log 7 and 8) were examined in 30 treatments for 10 days in aquarium scale. Parameters such as chlorophyll a, dissolved oxygen, phosphate and nitrate were tested at different time the same time. The results showed that the decline trend of nodularia in aeruginosa and mixed species treatments were better than other treatments and log 8 of bacterium was also more inhibitory effect than to log 7. Similar results were observed in double layer on agar medium and latter treatments had algaecide effect on nodularia. However, putida and fluorescens treatments had algaestatic properties. Concentration of chlorophyll a, dissolved oxygen and nitrate in all treatments, especially aeruginosa and mixed bacteria have been often decreased (p