Four groups of 4 dairy cows were fed a diet containing 0, 5, 15 and 50ppm cyanofenphos, O-ethyl O-4-cyanophenyl phenylphosphonothioate (Surecide ^®) for 30 days. Three cows from each group were sacrificed on day 30 and the remainders were kept on a normal diet for a 30-day recovery period. Milk samples were taken at specified intervals during the entire experimental period, and liver, kidney, muscle and fat samples were collected at sacrifices. Cyanofenphos and cyanofenphosoxon residues in milk and tissues were extracted with methanol/acetonitrile and determined by gas chromatography on a 3% OV-1 column using a flame photometric detector.
In the milk of cows the residues were found only on the 50ppm treatment. The highest level of cyanofenphos (0.25ppm) occurred at day 2 and 4. The oxon level (0.06ppm) peaked at day 4. The concentration of both compounds in milk decreased thereafter, and after 30 days of feeding the residue levels of cyanofenphos and cyanofenphos-oxon were less than the detection limits. The 50ppm treatment for 30 days resulted in residues of 0.9ppm cyanofenphos and 0.09ppm cyanofenphosoxon on an average in the fat, whereas other tissues generally contained one tenth the amount of these compounds.
At the lower dosages any detectable amounts of cyanofenphos or its oxon were hardly observed. At day 60, trace amounts (0.005ppm) of cyanofenphos were sporadically detected in the tissues.

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Some factors affecting the degradation of ¹⁴C-benthiocarb (S-4-chlorobenzyl N, N-diethylthiocarbamate) labelled at the benzene-ring in soils were studied. The degradation rates of ¹⁴C-benthiocarb in three different soils under upland, oxidative flooded and reductive flooded conditions were compared. ¹⁴C-Benthiocarb was rapidly degraded under oxidative conditions, but slowly under reductive conditions. Very small differences in the degradation rates were observed among different soils. Under oxidative conditions ¹⁴C-carbon dioxide was liberated remarkably with the degradation of ¹⁴C-benthiocarb. The degradation was remarkably retarded by sterilizing the soils. The repeated application of benthiocarb, or its incorporation into the soil with simetryne, CNP or propanil had no significant effect on the degradation rate.

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The photodegradation of benthiocarb (S-4-chlorobenzyl N, N-diethythiocarbamate) under ultraviolet lights or sunlight was investigated using ¹⁴C-labelled and unlabelled compounds. Benthiocarb in the aqueous solution was more rapidly degraded by irradiation with ultraviolet lights than seven common pesticides tested. The irradiation resulted in the formation of many degradation products such as benthiocarb sulfoxide, desethyl benthiocarb, 4-chlorobenzyl alcohol, 4-chlorobenzaldehyde, 4-chlorobenzoic acid, 4-hydroxy analogues of the alcohol, the aldehyde and the acid, 8 other identified compounds and about 20 unidentified compounds. Among these, 4-chlorobenzaldehyde and the alcohol were the major products. The degradation in the aqueous solution under sunlight was also considerably rapid, and most of the degradation products detected were the same as those produced by irradiation with ultraviolet lights. The irradiation on the thin film of benthiocarb on glass plate also resulted in the formation of the same degradation products as those in the aqueous solution.

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Residue analysis of benomyl [methyl 1-(buthylcarbamoyl)-2-benzimidazolecarbamate] and thiophanate-methyl [dimethyl 4, 4-o-phenylene bis (3-thioallophanate] (TM), in various plants and soil were investigated.
Benomyl and TM were converted to MBC (methyl 2-benzimidazolecarbamate) and then determined by high speed liquid chromatograph equipped with a fluorophotometric detector.
Benomyl was extracted from plants with ethyl acetate. The solution was concentrated to about 50ml and then extracted with 0.1N hydrochloric acid. Benomyl was hydrolyzed to MBC in this process. The acidic solution was washed with ethyl acetate and adjusted to pH 6.4, then extracted with dichloromethane. The solution was evaporated and the residue was dissolved in methanol.
Benomyl in soil was extracted with methanol and the solution was evaporated under vacuum. The residue was dissolved in ethyl acetate and to the solution 0.1N hydrochloric acid was added. The acidic solution was treated as that from plants. TM and its degradation product, MBC, in soil were extracted with methanol. The extract was acidified with hydrochloric acid, and TM was extracted with dichloromethane, while MBC remained in aqueous solution. TM was converted to MBC by refluxing with copper acetate in 50% aqueous acetic acid. The reaction mixture was adjusted to pH 6.4 and was extracted with dichloromethane. The dicholomethane solution was evaporated under vacuum, and residue was dissolved in methanol. Chromatography of the methanol solution was performed on a high speed liquid chroromatograph fitted with a Hitachi-Gel # 3010 glass column (3mm×50cm). The column was eluted with methanol and water (19+1). Flow rate was 1.7ml/min. A fluorophotometer with a flow cell (2×20mm) was used as a detector. Wave length for exitation was 285nm and that for emission was 315nm. Interfering and quenching phenomena of fluorescence were not observed.
The lower limit of detection for benomyl in crop and soil were 0.008ppm and 0.01ppm respectively and those for TM and MBC in soil were both 0.03ppm. Recoveries of benomyl were 74-90% in plants and 69-98% in soil, and those of TM and MBC were 75-122% and 62-75% respectively.

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Lecithin obtained from soybean plants at the time of producing soybean oil controls effectively several powdery mildews and rice blast disease. Since lecithin is a ubiquitous component in living organisms and its safety as a food additive is established, it is expected that this compound may be a safe agricultural fungicide and is applicable to vegetables even during harvest. Therefore, we examined the effect of lecithin on the growth of the cucumber powdery mildew fungus, Sphaerotheca fuliginea with a scanning electron microscope. After spraying 2000ppm of the lecithin on the lower surfaces of cucumber cotyledons, conidiospores of the pathogen were inoculated on the same place. Spore germination, hyphal elongation, conidiophore formation and sporulation were observed at certain intervals. The lecithin did not inhibit remarkably spore germination, but gave some effects on spore germination, hyphal elongation and sporulation. That is, germ tubes on treated lower surfaces were stunted and became shorter than that of control. Hyphal elongation on treated surfaces was delayed, and conidiophore formation and sporulation were poorer than those on control lower surfaces. It was a striking feature that hyphal tips on the lower surfaces of cucumber cotyledon treated with lecithin became deformed, namely thin membrane-like substance appeared around hyphal tips and expanded with time. More delayed and fewer conidiophores and conidiospores were observed on the lower surface treated with the lecithin than those on the control lower surfaces. In addition, many conidiospores which were unable to release from conidiospore chain were observed on conidiophores, and such conidiospores dangled like osmund from the conidiophores on lower surfaces of cucumber cotyledon treated with the lecithin.

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Methyl parathion is included in beta-cyclodextrin in 1:2 or 1:1 molar ratio. These and the inclusion compounds of four pyrethroids including bioallethrin, tetramethrin, resmethrin, and pyrethrins were examined for their insecticidal activity to certain cotton insects under laboratory conditions. Included methyl parathion (1:2 ratio) was as toxic as free one to Anthonomus grandis, while the persistency was remarkably improved, almost all remaining after 10 days on cotton leaves under green house conditions. Inclusion did not much reduce the toxicity of methyl parathion to a parasitoid, Campoletis sonorensis, but the possible reduction in use by inclusion may reduce its side effect to natural enemy of cotton pest insects. Pyrethroids were far less toxic to the parasitoid than methyl parathion and the inclusion further improve the safety characteristic. However, higher doses seemed required for included as compared to free pyrethroids to kill Anthonomus grandis. To Heliothis virescens the included methyl parathion was toxic, but pyrethroids were toxic only by contact, and the insect which fed the included pyrethroids seemed not to be affected.

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Absorption, translocation, and metabolism of 2-iso-propylphenyl N-methylcarbamate (Mipcin^®, MIPC) in rice plants and its degradation in soils were studied by using ¹⁴C-Mipcin labeled at methyl of iso-propyl group of ring substituted side chain.
¹⁴C-Mipcin was absorbed easily from roots and leaves of rice plants, translocated to upper parts, and was lost from leaves. As predominant metabolites in straw, 2-(1-hydroxy 1-methylethyl) phenyl N-methylcarbamate and 2-iso-propylphenyl N-hydroxymethylcarbamate were detected. In grain, conjugated metabolites which were hydrolyzed to 2-iso-propylphenylcarbamate by HCl were observed.
Degradation of Mipcin in soils was more rapid under upland conditions than under flooded conditions. The main degradation products were 2-iso-propylphenylcarbamate under upland conditions and 2-iso-propylphenol under flooded conditions.
Most of these metabolites were found to be less toxic than the parent compound with respect to the inhibitory activity on cholinesterase.

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Absorption, translocation, and chemical transformation of barban [4-chloro-2-butynyl-N-(3-chlorophenyl) carbamate] in plants were studied in relation to its selective herbicidal action.
Little difference were found in the rates of translocation and chemical transformation between the susceptible (oat: Avena sativa L. ‘Victoria’) and the tolerant (wheat: Triticum aestivum L. ‘Ushio’) plants. However, the rate of absorption of barban by the intact shoots of the susceptible plant was observed to be much higher than by those of the tolerant plant. In contrast to using intact shoots, the rates of barban absorption into the sectioned tissues were found to be almost identical with both susceptible and tolerant plants, in addition that protein synthesis was inhibited by barban to the same extent in both susceptible and tolerant plants.
It is concluded that one of the main factors in determining the selectivity of barban is the differential absorption by intact shoots of both plant species.

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When applied to the leaf surface of bean plants, (+)-trans and (+)-cis permethrin [3-phenoxybenzyl 3-(2, 2-dichlorovinyl)-2, 2-dimethylcyclopropanecarboxylate] were readily metabolized in bean plants. The half-life was about 7 days and 9 days, respectively, for trans and cis Permethrin. Both isomers of permethrin underwent ester cleavage, oxidation at the phenoxy group of the alcohol and probably at the geminal dimethyl group in the acid, and conjugation of the resulting carboxylic acids and alcohols. The major metabolites derived from the alcohol moiety were glucosides of 3-phenoxybenzyl alcohol, 3- (2′-hydroxyphenoxy) benzyl alcohol and 3-(4′-hydroxyphenoxy) benzyl alcohol, and those derived from the acid moiety were glucosides of 3-(2, 2-dichlorovinyl)-2, 2-dimethylcyclopropanecarboxylic acid and probably its hydroxylated derivatives.
Both permethrin isomers and their metabolites hardly moved from the application site to the other parts of the plants.

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