Avermectin (AVM) as a nonsystemic pesticide possesses a low effective utilization rate. Studies of the multifunctional pesticide delivery system for improving biological activity are developing prosperously. In this study, multifunctional avermectin/polysuccinimide with glycine methyl ester nanoparticles (AVM-PGA) were prepared by the selfassembly process. The AVM loading capacity was up to 23.7%. After 24 h of UV irradiation, there was still about 70% of AVM remaining in PGA 42 nanocarriers, as opposed to less than 5% of the free-form AVM. The rising ambient pH promoted the release of AVM using an in vitro releasing test, revealing a favorable pH-responsively controlled-release property. The mortality rate of Plutella xylostella with 2.5 μg/mL of AVM content of AVM-PGA 42 was 96.3% after 48 h, while that of free AVM was only 51.5%. In addition, the AVM could be detected in stems and all leaves treated with AVM-PGA 42 nanoparticles, whereas rare AVM was detected only in treated leaves for the free-form AVM, which achieved the transportation of nanocarriers carrying AVM in rice for the first time. Furthermore, the PGA nanoparticles performed a good growth promoting effect on rice. These results show that the AVM-PGA 42 nanopesticides have a great potential application prospect to control the pest and improve the drug utilization efficiency on agriculture.

The ionic liquid [HNMP]­Cl-catalyzed dehydration of fructose into 5-hydroxymethylfurfural (HMF) in deep eutectic solvents (formed by [Emim]Cl and different alcohols) was investigated. The experimental results indicated that the polarity of an alcohol and its stereostructure were major factors influencing fructose dehydration and that isopropanol was the optimum alcohol for the conversion system. Studies on the mechanism of the alcohol effect indicated that an alcohol could influence the formation of intermediates and their further transformation via the hydrogen bonds formed with [Emim]Cl and [HNMP]­Cl. For the normal alcohols, the shorter the chain, the higher is the polarity and the stronger the ability to form the hydrogen bond; as a result, the alcohol with the shortest chain has the greatest negative effect on fructose dehydration. For the branched chain alcohols, the existence of steric hindrance led to their weaker ability to form the hydrogen bond with the ionic liquid so that their negative effects on the conversion were much smaller. The DES composed of equal moles of [Emim]Cl and isopropanol is the best one for the conversion of fructose into HMF catalyzed by [HNMP]Cl with an HMF yield of up to 89% after 3 h of reaction at 25 °C.

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Characterization and genetic engineering of plant transporters involved in the pesticide uptake and translocation facilitate pesticide relocation to the tissue where the pests feed, thus improving the bioavailability of the agrichemicals. We aimed to identify thiamethoxam (THX) transporters in rice and modify their expression for better brown planthopper (BPH) control with less pesticide application. A yeast library expressing 1385 rice transporters was screened, leading to the identification of an amino acid transporter-like (ATL) gene, namely OsATL15, which facilitates THX uptake in both yeast cells and rice seedlings. In contrast to a decrease in THX content in osatl15 knockout mutants, ectopic expression of OsATL15 under the control of the CaMV 35S promoter or a vascular-bundle-specific promoter gdcsPpro significantly increased THX accumulation in rice plants, thus further enhancing the THX efficacy against BPH. OsATL15 was localized in rice cell membrane and abundant in the root transverse sections, vascular bundles of leaf blade, and stem longitudinal sections, but not in hull and brown rice at filling stages. Our study shows that OsATL15 plays an essential role in THX uptake and its systemic distribution in rice. OsATL15 could be valuable in achieving precise pest control by biotechnology approaches.

BackgroundConjugating amino acid moieties to active ingredients has been recognized as an effective method for improving the precise targeting of the active form to the specific site. Based on the vectorization strategy, a series of amino acid–tralopyril conjugates were designed and synthesized as novel proinsecticide candidates, with the potential capability of root uptake and translocation to the foliage of crops.ResultsBioassay results showed excellent insecticidal activities of some conjugates, in particular, the conjugates 6b, 6e, and 7e, against the diamondback moth (Plutella xylostella), with equivalent insecticidal activity to chlorfenapyr (CFP). Importantly, conjugate 6e exhibited significantly higher in vivo insecticidal activity against P. xylostella than CFP. Furthermore, the systemic test experiments with Brassica chinensis demonstrated that conjugates 6e and 7e could be transported to the leaves, in contrast to CFP, which remained in the root.ConclusionThis study demonstrated the feasibility of amino acid fragment conjugation as a vectorization strategy for transporting non‐systemic insecticides into the leaves of B. chinensis while maintaining in vivo insecticidal activity. The findings also provide insights for subsequent mechanism studies on the uptake and transport of amino acid–insecticide conjugates in plants. © 2023 Society of Chemical Industry.