Bioassays for Benomyl Adsorption and Persistence in Soil Leon
نویسنده
چکیده
Two bioassay methods were modified to evaluate persistence, adsorption and biological availability of the fungicide benomyl in soil. The amount of biologically-available fungicide was assayed using the fungus Penicillium expansum Link ex Gray. The bioassay results were not significantly different from those obtained by spectrophotometry. The bioassays detected methyl 2-benzimidazole carbamate (MBC), which is the major toxic degradation compound of benomyl, to a limit of detection of 0.2 μg g and a limit of quantitation of 0.5 μg g in soil and leachate. The bioassays could be completed within two days. The amount of MBC adsorbed by soil varied, depending on soil type and fungicide concentration. In vitro soil degradation studies showed a half life for MBC of around four weeks.
منابع مشابه
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