Herbicide Toxicity to Lemna: Test
Comparative toxicity of 16 herbicides to Lemna
Toxicity is based on counting the fronds in the cultures each
day. The EC50 is the concentration of the
dissolved test substance that
gives a 50% inhibition of growth rate.
Data from Fairchild et al. 1997 (see below), cited in Appendix 5:
Davy, Richard Petrie, and Jerry Smrchek, EPA; Ted Kuchnicki and
PMRA, USEPA Scientific Advisory Panel Briefing "Proposal to
non-target plant toxicity testing under NAFTA." June 27-29,
Fairchild, J.F., D.S. Ruessler, P.S. Heverland and A.R. Carlson.
1997. "Comparative Sensitivity of Selenastrum capricornutum
and Lemna minor to Sixteen Herbicides." Arch. Environ.
Contam. Toxicol., 32: 353-357.
Lemna growth assays are
determine if and how toxic a chemical is to green
plants. Duckweeds are also used in research to understand why
a chemical is
toxic. Many classes of toxins have been studied, ranging
elements (e.g. selenium and heavy
metals) to fungal toxins, pesticides
and industrial chemicals.
- Lemna test abstracts from the Annual Meetings of the
Society for Environmental Toxicology and Chemistry (SETAC).
These abstracts provide the results from a wide variety of
US Meeting ] [ 2002
US Meeting ] [ 2002
SETAC Europe ]
- Photooxidation products of environmental contaminants.
Lemna was used to show that ultraviolet light enhances
of certain aromatic substances to more toxic products.
the laboratory of B.M.
Greenberg, University of Waterloo, Ontario:
Mallakin A et al. (1999) "Impacts of structural
photomodification on the toxicity of environmental contaminants:
anthracene photooxidation products." Ecotoxicol
Environ Safety 43(2):204-12.
- Water leaching from smelters and
tailings often contains heavy metals not recovered in
T.L. Williams, M.J. Lydy, and A.L. Youngman (Wichita State
University, KS) Utilization of a duckweed bioassay to evaluate
leaching of heavy metals
in smelter-contaminated soils. 12th Annual Conference
Waste Research, Kansas City, MO, 1997.
Fungi produce some of the most toxic
substances known. Lemna bioassays are useful in
discovering and studying these (often) food-borne toxins:
Vesonder, Ronald F.
and Weisleder, David (USDA, Peoria, IL) Metabolites from Fusarium
spp. inhibitory to growth of Lemna minor L.
TEKTRAN, United States Department
of Agriculture, Agricultural Research Service, 1998.
"Corn containing toxins produced by fungi when used as farm
animal food can make the animal sick. In this report,
the usefulness of a
bioassay using a water plant called duckweed is demonstrated
for finding toxins
in corn harmful to animals."
to abstract ]
Abbas, Hamed K., Duke,
Stephen O., Merrill, A.H., Wang, E. and Shier, W.T. (USDA/ARS
Southern Weed Science Lab.,
Stoneville, MS) "Phytotoxicity of australifungin produced by
Sporomiella australis AAL toxin and fumonisin B1 to
duckweed (Lemna pausicostata L.)" TEKTRAN, United
States Department of Agriculture, Agricultural Research
"This paper describes the effects of australifungin which is
a newly discovered ceramide synthase inhibitor. The
compounds that affect this
enzyme, especially fumonisin B1, are toxic to animals.
It is our goal
to find a safe and effective weed control agent that works at
site. We demonstrate in this study that australifungin
- Ethylene glycol is the
main component of automotive antifreeze:
Barber, John T.,
Dana A., Ensley, Harry E., Yatsu, Lawrence Y. (Tulane University),
Duckweed, diols and death. American Society of Plant
Physiologists Annual Meeting, 1997.
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Revised: April 25, 2003