Umurzokov Mirjalol, Kim Danhee, Kim Jin-Seog, Cho Kwang Min, Choi Jung Sup, Park Kee Woong, Lim Hee Nam
Daeseungbiofarm Co., Ltd., Daejeon, Republic of Korea.
Chemical Research Team, New Agrochemical Research Institute, Farmhannong, Nonsan-si, Republic of Korea.
Pest Manag Sci. 2025 Oct;81(10):7219-7231. doi: 10.1002/ps.70071. Epub 2025 Jul 17.
The research focused on developing effective photosystem II (PSII) inhibiting triazine-derived herbicidal compounds from the internal chemical library. Initially, the compounds were screened for their herbicidal activity using Spirodela polyrhiza (SPIPO) assays. Subsequently, compounds with stronger activity were synthesized on a gram scale and further investigated for their phytotoxicity, mobility, and mode of action.
In the SPIPO screenings, two compounds, K-31706 and K-31487, showed superior efficacy at concentrations exceeding 0.4 μm, surpassing the commonly used PSII inhibition herbicide, atrazine. Both compounds showed promising performance, especially in pre-emergence applications under greenhouse conditions, with the application rate causing 50% biomass reduction below 100 g a.i. ha. However, both compounds exhibited strong phytotoxicity on major monocot and dicot crops, particularly when applied pre-emergence. Absorption studies revealed that K-31706 and K-31487 have strong activity in both soil-only and overtop applications, with root-based absorption occurring in monocots like Digitaria ciliaris. K-31487 was effective across various application methods on Abutilon theophrasti, indicating dual root and leaf absorption in dicots. Nevertheless, leaf excision assays indicated that both compounds act as contact herbicides rather than systemic ones. Chlorophyll fluorescence induction (OJIP) curve and molecular docking analyses confirmed PSII inhibition, which is comparable with simazine and diuron, with suppressed electron transport via interaction with Q site amino acids of D1 protein.
Overall, K-31706 and K-31487 are nonselective PSII inhibitors that block the electron transport in PSII, positioning them as potentially useful active ingredients for further investigation. © 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
该研究聚焦于从内部化学文库中开发有效的光系统II（PSII）抑制性三嗪衍生除草剂化合物。最初，使用多根紫萍（SPIPO）试验筛选这些化合物的除草活性。随后，以克级规模合成活性更强的化合物，并进一步研究其植物毒性、迁移性和作用方式。
在SPIPO筛选中，两种化合物K-31706和K-31487在浓度超过0.4μm时表现出卓越的除草效果，超过了常用的PSII抑制性除草剂阿特拉津。这两种化合物均表现出良好的性能，特别是在温室条件下的苗前应用中，使生物量减少50%的施用量低于100g a.i./ha。然而，这两种化合物对主要的单子叶和双子叶作物均表现出强烈的植物毒性，尤其是在苗前施用时。吸收研究表明，K-31706和K-31487在仅土壤和苗上施用中均具有较强活性，在单子叶植物如毛马唐中存在基于根的吸收。K-31487对苘麻的各种施用方法均有效，表明在双子叶植物中存在根和叶的双重吸收。然而，叶片切除试验表明这两种化合物均为触杀型除草剂而非内吸型。叶绿素荧光诱导（OJIP）曲线和分子对接分析证实了PSII抑制作用，与西玛津和敌草隆相当，通过与D1蛋白的Q位点氨基酸相互作用抑制电子传递。
总体而言，K-31706和K-31487是阻断PSII中电子传递的非选择性PSII抑制剂，使其成为有潜力用于进一步研究的活性成分。© 2025作者。由John Wiley & Sons Ltd代表化学工业协会出版的《害虫管理科学》。
