The inclusion complex of chlorimuron-ethyl with β-cyclodextrin was prepared by the saturated aqueous method. The inclusion complex formed was characterized by ¹H NMR, X-ray diffraction (XRD), differential scanning calorimeter (DSC), and thermogravimetric analysis (TG). The results showed that there was clathration of chlorimuron-ethyl by β-cyclodextrin, and thus a new inclusion complex was formed. The solubility of the inclusion complex in water was enhanced 1.85-fold as compared with that of chlorimuron-ethyl (pH 7, 20°C).

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Pyflubumide is a novel acaricide with a unique chemical structure that contains a methoxy-substituted hexafluoroisopropyl group on the anilino moiety. The compound has shown remarkable activity against spider mites including strains resistant to existing acaricides collected from the fields of Japan. Since carboxin was developed in 1966, various carboxamides with the same mode of action, i.e., succinate dehydrogenase inhibitors, have been created and developed. Although succinate dehydrogenase plays an important role in energy metabolism in aerobic organisms, the practical usage of the carboxamides has been primarily limited to disease control and an acaricidal activity has never been reported. The study to create a new carboxamide molecule revealed that introducing a fluoroalkyl group at the 4′-position of the aniline molecule remarkably enhanced the acaricidal activity. This finding prompted extensive research to ultimately identify pyflubumide. In this report, details of the structure–activity relationships from the lead compound to pyflubumide are described.

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The effectiveness of acetylated glyceride (acetic and fatty acid esters of glycerol) developed as an adult repellent was clarified by observing the host selection behavior of the sweet potato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), on treated plant leaves. In a choice test between treated and untreated grape tomato leaves, it was observed that almost the same number of adults landed on the leaves, but the retention rates of adults settling under the leaves were 27% and 95%, respectively. Repellent behavior was induced within 5 sec of the adult’s landing on the plant surface. The repellent led to a large reduction in the number of eggs laid on grape tomato leaves as compared to untreated leaves. However, no adulticidal activity by direct foliar treatment and no insecticidal activity against the progeny by contact treatment were found on cucumber leaves.

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The photodegradation kinetics of octachlorodipropyl ether (OCDPE) in aqueous solution have been studied under select conditions. The photodegradation rate constants of OCDPE increase with the increases of temperature and pH. The photolysis rates of OCDPE in the investigated water follow the sequence of pure water>impoundment water>pond water>lake water. The photodegradation product of OCDPE is shown to be 2,3,3-trichloroprop-2-en-1-ol. We propose that the OCDPE photolytic pathways consist of dehydrochlorination and ether cleavage via ionic or radical mediated reaction.

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The imidacloprid-resistant strain of Aphis gossypii (RF₆₀) was further selected with imidacloprid to establish the more resistant strain (RF₇₅). After the selection for 15 generations, the resistance ratio relative to the susceptible strain increased from 66.60 to 72.60. The RF₇₅ strain showed different levels of cross-resistance to all the insecticides tested. Synergistic and metabolic enzyme assays suggested that carboxylesterase and cytochrome P450 may play important roles in the imidacloprid resistance.

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An analysis of seven pesticides in 160 yuza samples (100 by ordinary culture and 60 by environmentally friendly culture) was conducted. The detection rate of carbendazim was the highest and the levels were up to 5.15 mg/kg. The degradation order of the seven pesticides in yuza tea was as follows: acequinocyl>chlorpyrifos>spirodiclofen>carbendazim>deltamethrin>phosalone, prothiofos.

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The nicotinic acetylcholine receptor β1 subunit gene of the most imidacloprid-susceptible (OK) strain and the most imidacloprid-resistant (TS7) strain of Thrips palmi encoded a susceptible amino acid, Arg, at amino acid position 81. The OK and TS7 strains showed LC₅₀ values of 9.4 mg/L and 115.0 mg/L, respectively. The synergist, piperonyl butoxide, decreased the resistance ratio to one-third in the TS7 strain. These results suggest that the imidacloprid resistance in T. palmi is conferred mainly by cytochrome P450-mediated detoxification.

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