Possible use of viruses as a microbiological agent against harmful algal blooms

The ecological importance of aquatic viruses has recently been highlighted.We isolated 2 double stranded DNA Viruses, HaV and HcV, infecting harmful algal bloom (HAB)-causing microalgae, Heterosigma akashiwo and Heterocapsa circularisquama, respectively.We have been investigating their physiological and ecological features especially focusing on the relationships between viruses and host algae.Through cross infection experiments, it has been strongly suggested that viral infection play an important role in regulating the host population dynamics both quantitatively and qualitatively in the natural environment, especially in the final stage of H. akashiwo blooms.Based on the data accumulated so far, in the present paper, the possible use of the viruses to control HABs is discussed.