A NOVEL IMMOBILIZED ALGICIDAL BACTERIA (DINOSHIELD) FOR CONTROLLING HARMFUL DINOFLAGELLATES: ESTABLISHING APPLICATION RATES

Previous research investigated the bacterium, Shewanella sp. IRI-160, exhibitalgicidal activity against all harmful dinoflagellates tested while having no negative impacts on other phytoplankton groups tested. Shewanella sp. secrete soluble compounds responsible for the reported algicidal activity and does not require direct . may concerns about . Recent research explored delivering the algicidal product by immobilizing the bacteria and cell-free filtrate in retrievable non-toxic alginate hydrogel matrices designated “DinoSHIELDs”. This study focused on optimizing conditions for algicide delivery within the DinoSHIELD configuration. To establish an effective application rate, several factors were considered bacterial concentration, growth media, and preservation approach; algicidal filtrate potency; K brevis cell density and culture conditions; DinoSHIELD concentrations and contact/exposure time; as well as deployment materials. The objective was to identify an effective rate and limit the total cost and need for long-term cooled storage space while maximizing potency and product stability. This application rate will be tested at scale in future field efforts along the west coast of Florida, USA during active bloom events in confined and unconfined treatment plots up to one acre for routine red tide management in the region.

Primary Presenter: William Holland, Department of Commerce NCCOS (chris.holland@noaa.gov)

Authors:

Lynn Wilking, CSS Inc. Consolidated Safety Services, Inc.  (lynn.wilking@noaa.gov)

Ransom Hardison, National Centers for Coastal Ocean Science, National Oceanic and Atmospheric Administration,  (rance.hardison@noaa.gov)

Yanfei Wang, University of Delaware,  (yfwang@udel.edu)

Alan Kennedy, Environmental Laboratory, US Army Engineer Research and Development Center,  (alan.j.kennedy@usace.army.mil)

Kathryn Coyne, University of Delaware  (kcoyne@udel.edu)

Kaytee Pokrzywinski, National Centers for Coastal Ocean Science, National Oceanic and Atmospheric Administration,  (kaytee.pokrzywinski@noaa.gov)