Resistance evolution in weeds puts 2,4-D under the microscope
The new research will work to identify how it is that the major WA crop weed, wild radish (Raphanus raphanistrum), can resist the most widely-used broadleaf herbicide in the world, 2,4-dichlorophenoxyacetic acid (2,4-D).
Winthrop Professor Stephen Powles, Director of the UWA-based Australian Herbicide Resistance Initiative (AHRI), is leading the Australian Research Council Linkage project with industry partner Nufarm.
"With the international release of the first genetically modified 2,4-D-herbicide resistant crops imminent in the US, it is vital that evolved 2,4-D resistance in weeds be clearly understood and, hopefully, minimised," Professor Powles said.
The research will unravel the biochemical and molecular basis of 2,4-D resistance in wild radish. The herbicide 2,4-D is very similar to auxin, a key plant growth hormone that is involved in all stages of the plant life cycle. Determining how wild radish becomes resistant to 2,4-D while retaining normal auxin activity poses a significant research challenge.
Studies will investigate plant 2,4-D uptake and movement, its effectiveness at sites of action within the plant, and the potential for resistant plants to detoxify 2,4-D.
The ultimate aim of the research is to provide the science that will enable the effective use of the auxin-type herbicides in agriculture.