Chen Ronghua, Li Chaozheng, Zhao Di, Yang Guili, Zeng Lingda, Lin Fei, Xu Hanhong
State Key Laboratory of Green Pesticide/Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, College of Plant Protection, South China Agricultural University, Guangzhou, 510642, China.
Institute of Nanfan & Seed Industry, Guangdong Academy of Sciences, Guangzhou, 510316, China.
Nat Commun. 2025 May 10;16(1):4347. doi: 10.1038/s41467-025-59582-9.
Controlling weeds before their emergence is crucial for minimizing their impacts on crop yield and quality. Bipyridyl herbicides (BPyHs), a class of highly effective and broad-spectrum herbicides, cannot be used as pre-emergence herbicides because they can be absorbed and inactivated by negatively charged soil after application. Here, we design and fabricate an adsorbed-but-active supramolecular pre-emergence herbicide consisting of cationic polyacrylamide and bipyridyl herbicides (CPAM-BPyHs). CPAM is a positively charged polymer. It can preferentially bind to soil particles and shift their electric potential to a more positive value. Thus, it prevents not only runoff but also inactivation of BPyHs. We also develop a BPyHs-resistant rice line by mutation of the gene encoding L-type amino acid transporter 5 (OsLAT5). Field trial results show that the weed control efficiency of CPAM-diquat for direct-seeded herbicide-resistant rice line exceeds 90%. The herbicidal activity can maintain up to one month with only one application. This work offers a method for rice weed control and provides insights into the design of pesticides to prevent soil inactivation and runoff.
在杂草出苗前进行控制对于将其对作物产量和品质的影响降至最低至关重要。联吡啶类除草剂（BPyHs）是一类高效广谱除草剂，但不能用作苗前除草剂，因为施用后它们会被带负电荷的土壤吸收并失活。在此，我们设计并制备了一种由阳离子聚丙烯酰胺和联吡啶类除草剂组成的吸附但活性的超分子苗前除草剂（CPAM-BPyHs）。CPAM是一种带正电荷的聚合物。它可以优先结合到土壤颗粒上，并将其电位转变为更正的值。因此，它不仅可以防止径流，还可以防止BPyHs失活。我们还通过对编码L型氨基酸转运蛋白5（OsLAT5）的基因进行突变，培育出了一种抗BPyHs的水稻品系。田间试验结果表明，CPAM-敌草快对直播抗除草剂水稻品系的杂草防除效率超过90%。只需一次施用，除草活性就能维持长达一个月。这项工作提供了一种水稻杂草防治方法，并为防止土壤失活和径流的农药设计提供了思路。
