The Alleopathic Interactions Between Karlodinium micrum and Amoebophrya sp.

            In the Protistan Ecology lab, we work with microscopic organisms like dinoflagellates.  Dinoflagellates are unicellular protists commonly regarded as algae.  When they occur in abundant numbers, they produce algal blooms, better known as red tides.  These red tides can cause a number of problems that can include fish kills and decreases in the economy through tourism and the aquaculture.  Recently it has been implicated that viruses, eukaryotic parasites and bacteria are microbial controls of these red tides.  In order for us to find even better control of these red tides, we must first understand the biology and ecology of dinoflagellates and then the ecology of red tides that they are prone to cause.

            Two of the dinoflagellates that we grow in our lab are Karlodinium micrum and Akashiwo Sanguinea.  Karlodinium micrum is a toxic dinoflagellate that forms red tides in the Chesapeake Bay with densities as high as 100,000 cells/mc.  Akashiwo Sanguinea is a non-toxic dinoflagellate that also forms red tides in the Chesapeake Bay with densities at about 1,000 cells/mc.  In our lab, we also grow a host specific parasite dinoflagellate, Amoebophrya species, which infects other free-living dinoflagellates. 

            During this summer, my project was to determine whether Karlodinium micrum had an affect on the infection rates of Akashiwo Sanguinea with Amoebophrya species.  My results concluded that Karlodinium micrum did in fact have an affect on the infection rates of Akashiwo Sanguinea with Amoebophrya species, causing them to decrease.  What I was not able to prove was whether the bacteria caused the decrease or dissolved chemicals utilized in my experiment.