Comparative effects of herbicides on photosynthesis and growth of tropical estuarine microalgae

Magnusson, Marie, Heimann, Kirsten, and Negri, Andrew P. (2008) Comparative effects of herbicides on photosynthesis and growth of tropical estuarine microalgae. Marine Pollution Bulletin, 56 (9). pp. 1545-1552.

[img] PDF (Published Version)
Restricted to Repository staff only

View at Publisher Website:


Pulse amplitude modulation (PAM) fluorometry is ideally suited to measure the sub-lethal impacts of photosystem II (PSII)-inhibiting herbicides on microalgae, but key relationships between effective quantum yield [Y(II)] and the traditional endpoints growth rate (μ) and biomass increase are unknown. The effects of three PSII–inhibiting herbicides; diuron, hexazinone and atrazine, were examined on two tropical benthic microalgae; Navicula sp. (Heterokontophyta) and Nephroselmis pyriformis (Chlorophyta). The relationships between Y(II), μ and biomass increase were consistent (r2 greater-or-equal, slanted 0.90) and linear (1:1), validating the utility of PAM fluorometry as a rapid and reliable technique to measure sub-lethal toxicity thresholds of PSII-inhibiting herbicides in these microalgae. The order of toxicity (EC50 range) was: diuron (16–33 nM) > hexazinone (25–110 nM) > atrazine (130–620 nm) for both algal species. Growth rate and photosynthesis were affected at diuron concentrations that have been detected in coastal areas of the Great Barrier Reef.

Item ID: 6851
Item Type: Article (Research - C1)
ISSN: 1879-3363
Keywords: diatom; chlorophyte; diuron; triazine; PAM fluorometry; Great Barrier Reef
Date Deposited: 03 Mar 2010 01:06
FoR Codes: 05 ENVIRONMENTAL SCIENCES > 0502 Environmental Science and Management > 050204 Environmental Impact Assessment @ 50%
05 ENVIRONMENTAL SCIENCES > 0503 Soil Sciences > 050399 Soil Sciences not elsewhere classified @ 50%
SEO Codes: 86 MANUFACTURING > 8607 Agricultural Chemicals > 860799 Agricultural Chemicals not elsewhere classified @ 50%
86 MANUFACTURING > 8607 Agricultural Chemicals > 860703 Crop Protection Chemicals @ 50%
Downloads: Total: 2
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page