Group 15 (VLCFA inhibitors) Resistance

A GHRAC Working Group published common advices regarding the combination or sequence of actives ingredients belonging to group 15. The recommendation letter can be accessed here.

In January 2020, HRAC updated the mode of action classification scheme, adding new mode of action classes and reviewing the correct positioning of each active ingredient. For legacy HRAC group N it turned out that most of its active ingredients needed to be moved into HRAC group 15 (legacy group K3) and class N was deleted.

Combinations or sequences of products containing active ingredients from different HRAC groups are part of resistance management recommendations. In line with this advice, it is common practice for European farmers to tank-mix or sequence products of the former HRAC groups N and K3 to control grasses like Alopecurus spp or Lolium spp.

Based on this experience and the fact that HRAC group 15 (K3) covers a multi-enzyme mode of action with a complex pattern of substrate specificity, combinations or sequences of products containing active ingredients from the former HRAC Groups N and K3 (new Group 15) are still supported by HRAC.

See the GHRAC Group 15 Working Group recommendation letter

Global HRAC Team
Executive Committee / Communication Group / Group 15 Working Group