The process of eliminating high-risk pesticides is on the agenda of the Plant Protection Organization.
2025-07-28
Controlling weeds before they emerge is crucial for minimizing their impact on crop yield and quality. Bipyridyl herbicides are a group of highly effective, broad-spectrum herbicides that cannot be used as pre-emergent herbicides because they can be absorbed and inactivated by negatively charged soil after application.
In an article published in Nature on May 10, 2025, Chinese researchers reported the design and production of a supramolecular, absorbed but active pre-emergent herbicide composed of cationic polyacrylamide and bipyridyl herbicides (CPAM-BPyHs). CPAM is a positively charged polymer that can preferentially bind to soil particles, shifting their electrical potential to a more positive value. This not only prevents runoff but also inhibits the inactivation of BPyHs.
The article mentions the development of BPyHs-resistant rice through a mutation in the gene encoding the L-type amino acid transporter 5 (OsLAT5). Field trial results showed that the weed control efficacy of CPAM-diquat for direct-seeded, herbicide-resistant rice lines exceeded 90%. The herbicidal activity can persist for up to one month with a single application. This work provides a method for weed control in rice and offers insights into designing pesticides to prevent soil inactivation and runoff.
News source: https://www.nature.com/articles/s41467-025-59582-9
