Tri-allate’s multisite action could strengthen fight against herbicide-resistant grassweeds

Rothamsted Research has found that tri-allate may play a greater role in managing herbicide-resistant grassweeds than previously thought, as it acts through multiple biological targets rather than a single mode of action. These findings suggest tri-allate could slow the development of herbicide resistance, similar to how multisite fungicides are used to manage septoria in wheat.

Researchers compared tri-allate, flufenacet, and EPTC on blackgrass using controlled growth experiments and advanced lipid profiling. While all three are classified in HRAC Group 15, the study found they affect plant metabolism in different ways. Dana MacGregor of Rothamsted Research noted that tri-allate acts within the expected biochemical pathway and at an earlier stage in another part of the plant cell, indicating a multisite mode of action.

This discovery may strengthen tri-allate’s role in integrated weed management, especially as herbicide resistance remains a challenge in cereal production. Industry representatives note that tri-allate can complement other Group 15 products, such as flufenacet, due to its distinct biological activity. Researchers also report that no resistance to Group 15 herbicides has been confirmed in blackgrass, suggesting tri-allate’s multisite activity could help maintain the effectiveness of current herbicide programs when used in diversified resistance management strategies.

Source: Farmers Weekly