A leaching column is composed of a 1/5000-are Wagner pot filled with layers of sand, test soil, treated soil, gravel, and a pile of coarse sea sand on top. The leaching property is expressed by the precipitation that transports a pesticide vertically 10cm through soil. The reliability of a method is confirmed by the agreement between the experimental data and the simulation. For a pesticide which shows little movement, its removal % from the treated soil layer by the total precipitation can be another index. The removal % of thiram by a 504-mm precipitation was 25% and that of sodium dimethyldithiocarbamate by a 940-mm precipitation 53%, and the decomposition % of them were 0 and 11%, respectively. EDB is neither adsorbed on sand nor on Tsukuba soil. More than 46-mm and 68-mm precipitation seem to be required for non adsorptive pesticides like EDB go down 10cm vertically through sand and Tsukuba soil, respectively.

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The therapeutic potency of intraperitoneally administered methocarbamol was examined against acute oral intoxication of rats caused by lethal doses of pyrethroids (fenvalerate, cypermethrin, fenpropathrin and permethrin). Methocarbamol was initially administered a dose of 400mg/kg (body weight), followed by repeated doses of 200mg/kg, when tremors or hyperexcitability to sound was observed. Methocarbamol markedly decreased the mortality; 80% mortality caused by an administration of 850mg/kg (body weight) fenvalerate to 0%, 80% mortality by 850mg/kg cypermethrin to 0%, 60% mortality by 100mg/kg fenpropathrin to 0% and 70% mortality by 850mg/kg permethrin to 10%, and it was effective in alleviating motor symptoms such as fibrillation, tremors, hyperexcitability, clonic seizures and/or choreoathetotic movements. A subcutaneous administration of 25mg/kg (body weight) atropine sulfate was also effective in mitigating salivation produced by fenvalerate and cypermethrin.

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Thirty-nine O-alkyl S-substituted methylphosphonothiolates were synthesized from corresponding sodium O-alkyl methylphosphonothioate by alkylation and their insecticidal activity was examined. Most of the compounds showed high insecticidal activity against two strains of houseflies (SRS; a susceptible strain and 3rd Yumenoshima; a resistant strain). Their insecticidal activity was much higher than that of fenitrothion, diazinone and other common organophosphorus insecticides. The most active compound was O-ethyl S-2-propynyl methylphosphonothiolate with LD₅₀ values of 0.0072μg/fly and 0.16μg/fly to SRS and 3rd Yumenoshima, respectively. Some other compounds also demonstrated similar activity.

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In aerobic condition, a phosphine-susceptible strain of the rust red flour beetle, Tribolium castaneum, at the larval, pupal and adult stages, absorbed more phosphine than a resistant strain, although no phosphine uptake was observed in both strains in anaerobic condition. And both strains showed same uptake of phosphine in the tissues of the homogenized insects in glycine buffer. The supernatant fraction at 100, 000×g contained a main factor responsible for the intake of phosphine. The activity of this factor was promoted by the presence of molecular oxygen and was stable at pH 5-9 and temperatures up to 50°C. The results led to a scheme for the insect's resistance mechanism to phosphine.

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Bialaphos, L-2-amino-4-[(hydroxy) (methyl) phosphinoyl] butyryl-L-alanyl-L-alanine, at a concentration of 0.3 to 3mM did not inhibit glutamine synthetase (L-glutamine: ammonia ligase (ADP), EC 6.3.1.2, GS) extracted from shoots of Japanese barnyard millet (Echinochloa utilis OHWI). However, low GS activity was observed in the shoots treated with bialaphos. On the other hand, L-2-amino-4-[(hydroxy) (methyl)phosphinoyl]butyric acid (L-AMPB), a metabolite of bialaphos, inhibited GS both after extraction and in the shoot. The results suggest that bialaphos was metabolized into L-AMPB in plants and inhibited GS. The quantitative analysis of free amino acids in the bialaphos treated shoots showed a remarkable decrease in glutamine content 48hr after the treatment. An exogenous application of glutamine increased the glutamine to some extent in the bialaphos-treated shoots, but did not antagonize bialaphos in the herbicidal activity. Thus, it appears that a decrease of glutamine content by the herbicide was not a main factor to induce the herbicidal activity.

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An increase free ammonia content was confirmed in Japanese barnyard millet (Echinochloa utilis OHWI), crabgrass (Digitaria adscendens HENR.), livid amaranth (Amaranthus lividus L.) and purple nutsedge (Cyperus rotundus L.) treated with bialaphos, L-2-amino-4-[(hydroxy) (methyl) phosphinoyl] butyryl-L-alanyl-L-alanine. The ammonia content reached about 30 to 100 times higher than the control's in 24 to 48hr after the treatment. The increment was more marked in shoots than in roots of the barnyard millet, and more in leaves than in stems of livid amaranth. The accumulation was not momentary, but persistent until the death of the plant. Such a remarkable accumulation of ammonia was not observed in plants treated with any other herbicide. Therefore, the ammonia accumulation is considered to be a particular action caused by bialaphos. The close correlation between the free ammonia content and the herbicidal activity indicated that the toxicity of accumulated ammonia is a primary factor to the herbicidal activity of bialaphos.

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Condensation of amidinohydrazones with ethoxymethylenemalononitrile gave 2, 3-dihydro[1, 2, 4]triazolo[1, 5-c]pyrimidines in moderate to high yields. Of the variously substituted amidinohydrazones, aldehyde 4-monosubstituted ones were most reactive in the condensation, regardless of the nature of the 4-substituent. The 2, 3-dihydro compounds were oxidized with iron (III) chloride in aqueous acetic acid or with iodine in ethyl alcohol to give the corresponding [1, 2, 4]triazolo[1, 5-c]pyrimidines. Thirty-eight compounds were subjected to fungicidal screening tests, which showed no or weak activity against test organisms.

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The study on the mating behavior of the yellow mealworm, Tenebrio molitor L. indicated the presence of a sex attractant to the male and a copulation release pheromone. The former secreted by the female was identified as 4-methyl-1-nonanol. The latter was found in both male and female and was synergized with 4-methyl-1-nonanol.

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Three soils were perfused with ¹⁴C-molinate (S-ethyl perhydro-2-¹⁴C-azepin-1-carbothioate) and non-labelled molinate, and the number of molinate-degrading microorganisms in a perfused soil was enumerated. The soil perfusion did not change the degrading activity of all three soils. Considerable quantities of S-carboxymethyl derivatives were accumulated during the perfusion. ¹⁴CO₂ and other degradation products, four of which could be identified, were also yielded. Various strains of fungi, bacteria and actinomycetes isolated from Anjo soil degraded molinate and the ratio of these degrading microorganisms to each group of total microbial population was approximately 30%, which did not change significantly during the soil perfusion. The microorganisms degraded molinate through a co-metabolic process. Some strains of the microbes which had high degrading activity were identified as Mycobacterium sp., Flavobacterium sp., Streptomyces sp., and Fusarium sp.

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The brush-border membrane vesicles were isolated from the midgut epithelial cells of the last instar cabbage armyworm larvae (Mamestra brassicae). It was observed that ¹⁴C-UDP-N-acetylglucosamine (UDP-AGA) bound fast to the vesicles at the optimum pH of 7.0. Almost 90% of the binding was inhibited by polyoxin D. Chitin was synthesized by the vesicles in vitro in the presence of chitodextrin as a primer. These facts suggested that much of the binding was based on the ¹⁴C-UDP-AGA-chitin synthetase binding, whose activity was stronger at 20°C than 25°C. On the other hand, the chitin synthesis by the vesicles progressed much faster at higher temperatures, indicating that the turnover of the binding would be faster at higher temperatures. The polyoxin D-treated vesicles retained the binding activity at the optimum pH 7.5, although UDP-ACA's binding activity became weak about one tenth of the original. The results led to a conclusion that the brush-border membrane vesicles had two substances bound to UDP-AGA, one would be chitin synthetase and the other a UDP-AGA transporter. However, the amount of UDP-AGA bound to the polyoxin D-treated vesicles was too small to conclude that the binding was based on the UDP-AGA transporter.

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The degradation of (1R, cis)- and (1R, trans)-isomers of cypermethrin [(RS)-α-cyano-3-phenoxybenzyl (1RS)-cis, trans-3-(2, 2-dichlorovinyl)-2, 2-dimethylcyclopropanecarboxylate] in two soils was studied under laboratory conditions, using ¹⁴C preparations labeled separately in the cyclopropyl and benzyl rings. The half-life of disappearance was 4.1 to 17.6 days for the trans-isomer and 12.5 to 56.4 days for the cis-isomer. The insecticide was degraded via pathways including cleavage of the ester or diphenyl ether bond, hydroxylation at the 4-position of the phenoxy ring, and hydrolysis of the cyano group to the amide and carboxyl groups. The main degradation route was hydrolysis of the ester linkage. The resultant products underwent further degradation to form ¹⁴CO₂ and bound residues. A larger amount of ¹⁴CO₂ was evolved in soils treated with the less persistent trans-isomer and with the benzyl-¹⁴C preparation. In contrast, a larger amount of bound ¹⁴C was formed in soils treated with the cis-isomer and with the cyclopropyl-¹⁴C preparation. Although a trace amount of cypermethrin appeared in the effluent from sand containing less than 0.1% organic matter, there was no leaching of cypermethrin with water through other three types of soil columns, when leaching was started immediately after treatment or after a 30-day preincubation of the treated soil columns.

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A simple high-performance liquid chromatographic (HPLC) method for the residue analysis of ethylenethiourea (2-imidazolidinethione, ETU) in onions, tomatoes, watermelons and lettuces was developed. Extracts of ETU from the vegetables were adjusted to pH 8 with ammonium hydroxide or sodium hydroxide solution, and poured onto an Extrelut^® column for cleanup. ETU from the column was eluted with dichloromethane. The effluent was analyzed by a high-performance liquid chromatograph (HPLC) equipped with an ultraviolet detector operating at 240nm. The limit of detection was 0.01ppm, and the recoveries of ETU from onions, tomatoes, watermelons and lettuces at a fortification level of 0.4ppm ranged 76 to 90%. This was an improved method on Nitz's Extrelut^®-column method, that requires potassium fluoride-treatment.

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The degradation of ¹⁴C-orbencarb [S-(2-chlorobenzyl-ring-U-¹⁴C) N, N-diethylthiocarbamate], a herbicide for controlling weeds in upland crops, was studied under various soil conditions. Orbencarb was more rapidly degraded under upland conditions, than under flooded conditions. The degradation was retarded in sterile soils. Under upland conditions, ¹⁴CO₂ evolved rapidly in soil, where the half-lives of orbencarb were 18 to 26 days. Orbencarb sulfoxide, monodesethyl-orbencarb, methyl 2-chlorobenzylsulfoxide, methyl 2-chlorobenzylsulfone and 2-chlorobenzylsulfonic acid were identified as orbencarb's major degradation products and N-ethyl-N-vinyl-orbencarb, N-ethyl-N-β-hydroxyethyl-orbencarb, 4-hydroxyorbencarb, 5-hydroxy-orbencarb, didesethyl-orbencarb, 2-chlorobenzyl alcohol, 2-chlorobenzoic acid and methyl 2-chlorobenzylsulfide as its minor. Soil bound residues derived from its ¹⁴C-U-benzene ring were found in humic acid, hulvic acid and humin fractions, and its benzene ring was finally degraded to ¹⁴CO₂.

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The absorption, translocation and metabolism of ¹⁴C-orbencarb [S-(2-chlorobenzyl-U-¹⁴C) N, N-diethylthiocarbamate] were studied in soybean plants. The absorption and translocation of radioactivity derived from ¹⁴C-orbencarb, which was applied onto the soil surface at a rate of 5kg/ha, increased as the plants grew. The plants at the flowering, green seed and mature stages absorbed 0.8, 9.3 and 9.1% of the applied radioactivity, respectively. The radioactivity absorbed was highest in the leaves and lowest in the seeds, ¹⁴C-Orbencarb was rapidly transformed to water-soluble metabolites in the plant. The major metabolites identified were 2-chlorobenzyl alcohol and 2-chlorobenzoic acid in both free and conjugated forms, 2-chlorobenzylsulfonic acid and methyl 2-chlorobenzylsulfone, and the minor metabolites were orbencarb sulfoxide, monodesethyl-orbencarb, didesethyl-orbencarb, N-ethyl-N-vinylorbencarb, 4-hydroxy-orbencarb, 5-hydroxy-orbencarb and methyl 2-chlorobenzylsulfoxide.

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The relationships between growth conditions and degradability of 4 isolated strains of the herbicide molinate (S-ethyl perhydroazepin-1-carbothioate)-degrading microorganisms, Mycobacterium sp. (B-1), Flavobacterium sp. (B-2), Streptomyces sp. (A-1), and Fusarium sp. (F-1), and the mechanisms of molinate degradation by them were investigated. None of these microorganisms could utilize molinate as a sole source of carbon and energy for growth and they needed other carbon sources. The three strains of microbes, B-2, A-1 and F-1, also needed other nutrient sources for the degradation of molinate while B-1 did not. The mode of molinate metabolism by these strains was found to be co-metabolism. Excess concentrations of the nutrient sources repressed the degradation by B-1 and B-2, but promoted by A-1. Adaptive enzymes seemed to be responsible for the first step of the molinate metabolism by A-1, whereas both constitutive and adaptive enzymes by B-1 and B-2. These four strains also responded differently to pH and temperature conditions.

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