Growth and domoic acid production of Pseudo-nitzschia on multiple scales

Abstract

The toxin-producing diatom Pseudo-nitzshcia has been monitored in a bloom for the last three years (2009-2011) in East Sound, WA. To expand the understanding of the dynamics of toxin production, especially in response to climate change and ocean acidification, two additional studies were conducted, including an ocean acidification mesocosm, and a laboratory growth experiment using low pH and low Silica conditions. Results from the mesocosm experiment were inconclusive. The Pseudo-nitzschia multiseries cultures grown in the laboratory were grown under low pH and low silica conditions. The pH was controlled by adding CO2 saturated water to the cultures, instead of HCl, which has been previously done by other studies. Growth of P. multiseries was unaffected by low pH, and was negatively affected by silica limitation.