Fungicidal tests

A series of benzoxazolo[3,2-r][l,2,4]triazoles have been synthesized and submitted to herbicidal and fungicidal testing < 1997IJC(B)711 >, the most active being compound 385 (Figure 25) in both analyses. 

The action of anti-oomycete fungicides on spectrin-like protein(s) localization was compared with that of fluopicolide. Different times of treatment were tested, from 3 min to 24 h. Figure 19.6 illustrates the results obtained after 2 h of treatment. None of the fungicides tested (iprovalicarb, fenamidone, dimethomorph, metalaxyl and zoxamide) induced spectrin-like protein redistribution. Unlike for... 

Florasulam and trifloxystrobin are both observed to metabolize rapidly in the wheat cell culture system (Figure 4), with half lives calculated using a nonlinear fit at 1S.4 and 15.S hours, respectively. Azoxystrobin was also observed to be metabolized, but the rate of metabolism was much slower than that of florasulam and trifloxystrobin (84% parent remaining 48 hours after treatment). It was not possible to accurately calculate the half life for azoxystrobin (the half life exceeded the incubation time), but it was extrapolated to be approximately 230 hours. All the other fungicides tested were stable over the 48 hour... 

Table 10 Paint film fungicide test methods (www.oecd.org, 2000, Bagda, E., 2000)...

Evaluations have been conducted using deer, a multiple-choice preference-testing apparatus, and tetramethylthiuram disulfide [137-26-8] (TMTD) (29) or the fungicide thiram as a standard repeUent for competitive tests with repeUent-treated food (78). 

Bunte salts have bacterial, insecticidal, and fungicidal properties, and are also used as chelating agents (qv) or surfactants (qv) (97,98). Bunte salts have been tested for preirradiation protection for mammals exposed to lethal radiation doses (99,100) (see Radioprotectiveagents). 

Another section of the EPA, the Office of Prevention, Pesticides, and Toxic Substances (OPPT), has recently updated and harmonized its testing guidelines for evaluating the developmental and reproductive effects of pesticides and industrial chemicals to include an assessment of endocrine disrupting properties. These guidelines will be used in future testing of pesticides under both the Toxic Substances Control Act (TSCA) and the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). 

Of agricultural importance is the plant-growth regulating activity of 6,8-dichloro-2-methyl-3-carboxymethyl-4(3H) quinazolinone which was as potent as 2,4-dichlorophenoxyacetic acid in the Lepidium test. 4-Hydroxy-5,6,7,8-tetrahydroquinazoline has been patented with reference to fungicidal activity. 

This type of test may be used to investigate bactericidal, sporicidal or fungicidal activity. 

This far into a nitrosamine symposium it should hardly be necessary to point out that nitrosamines are technically just one of a group of Ji-nitroso compounds that also includes nitros-amides, nitrosocarbamates, nitrosoureas, etc. Or that nitrosa-table pesticides encompass all the categories just mentioned and more. Or that many diverse pesticides, including herbicides, insecticides, and fungicides have been converted to Ji-nitroso derivatives in the laboratory (a recent review contained a 3-page, probably incomplete, compilation), or that some of the Ji-nitroso compounds thus synthesized were determined to be carcinogenic in test animals or mutagenic in various assays. 

Analytical chemistry is a critical component of worker safety, re-entry, and other related studies intended to assess the risk to humans during and subsequent to pesticide applications. The analytical aspect takes on added significance when such studies are intended for submission to the U.S. Environmental Protection Agency and/or other regulatory authorities and are thus required to be conducted according to the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) Good Laboratory Practice (GLP) Standards, or their equivalent. This presentation will address test, control, and reference substance characterization, use-dilution (tank mix) verification, and specimen (exposure matrix sample) analyses from the perspective of GLP Standards requirements. 

Further insight on the frequency of multiple residues is evident in Table 14.4, which shows the number of residues found per sample for selected foods tested in 2004 by the PDP. Conventional apples were found to contain, on average, 3.6 residues, while the one positive organic sample had a very minute level of the post-harvest fungicide thiabendazole. The level of residue found in the one positive organic apple sample was 0.0002 parts per million, while the mean thiabendazole residue found in 641 positive conventional samples was 0.43 ppm, over 2100 times higher than the level found in the organic sample. 

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