Test of biostimulant effect of microalgae (Phaeodactylum tricornutum) on basil (Ocimum basilicum)

• Published in: NIBIO Rapport 2023
• Main Authors: Øgaard, Anne Falk, Umetani, Ikumi, Kechasov, Dmitry
• Format: Report
• Language: English

This report shows results from an experiment where it was investigated whether a powder of freeze-dried microalgae (Phaeodactylum tricornutum) had a biostimulating effect on the growth and content of nutrients and antioxidants in basil (Ocimum basilicum). The effect of the microalgae powder was tested as a supplement to either mineral fertilizer or a commercial organic fertilizer. We found no significant effect on the yield of applied microalgae powder, but there was a tendency for a higher yield with added microalgae powder for the treatment with organic fertiliser. This may be due to additional nitrogen supply with the microalgae powder. With mineral fertiliser, there was the opposite tendency, highest yield without microalgae powder. The only statistically significant effect of the microalgae powder was an increase in the concentration of boron for the treatment with organic fertiliser. This was probably an effect of a significant additional supply of boron with the microalgae biomass. There was a tendency for an increased concentration of copper with the addition of microalgae powder with both mineral and organic fertiliser, although the additional copper supply with the microalgae powder was small. With organic fertiliser, there was also a tendency towards increased phosphorus and potassium concentrations with the addition of microalgae powder. This could be a biostimulating effect as the additional phosphorus and potassium supply with the microalgae powder was small, but as mentioned, the effect was not statistically significant. We found no significant differences between the treatments for total antioxidant content.