Effect of Nannochloris sp. on the Toxicity of Four Algae

Abstract

The effect of Nannochloris sp. on the toxicity of cultures of four algae was evaluated using a Microtox 500 that measures the effect on a light-producing bacterium, Vibrio fischeri. Cultures of four algae produced a toxic effect, but in the presence of Nannochloris sp., the effect was reversed, and a stimulatory effect was observed. The effect was tested for Microcystis aeroginosa, Cyclotella menengheniana, Scenedesmus dimorphis, and Lyngbya sp. using cultures obtained from the University of Texas Culture Collection of Algae.

Keywords:

• Red tide
• HABs
• Allelopathy

Notes

^a N=5.

^bC, control sample: 50 mL of culture; T, test sample: 50 mL of each culture, with the following concentrations (million cells/L): S. dimorphis, 2.0; Nannochloris sp., 2.2; C. meninghiniana, 2.5; M. aeroginosa, 3.0; Lyngbya sp., 3.5.