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Background: Conjugating 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. Results: Bioassay 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. Conclusion: This 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. [ABSTRACT FROM AUTHOR]

Summary: 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. [ABSTRACT FROM AUTHOR]