Effect of UV‐B radiation and humic substances on growth and motility of Gyrodinium aureolum

• DOI: 10.4319/lo.1993.38.7.1570
• Publication Date: 2010-05-17T23:55:49Z
• Authors: Tom Nielsen; Nils G.A. Ekelund
• Keywords: Dinoflagellate; Phototaxis

We investigated the effect of ultraviolet‐B radiation (280–320 nm) on growth and motility marine dinoflagellate Gyrodinium aureolum in presence humic substances. The specific rate after 7 d UV‐B BE (biologically effective radiation) exposure (2.15 kJ m −2 −1 ) decreased by 92% compared to control. for treated cells increased 18, 26, 10% when were cultured medium enriched with substances (1.7, 4.2, 8.3 mg liter ). However, was lower at highest substance than two concentrations. When used as a filter shade organisms from without substantial changes amount white light, instead being added medium, concentration had little or no G. aureolum, whether not. Phototactic orientation UV‐B‐treated significantly weaker control actinic light (400–700 nm, 47 during treatment reduced inhibition positive phototaxis aureolum.