Synthetic auxins might be the oldest kids on the herbicide block but that doesn’t mean they’re well understood.
There’s actually a huge knowledge gap that researchers like AHRI’s Dr Danica Goggin are trying hard to fill in a bid to find ways to overcome resistance to this herbicide group in weeds like wild radish.
In AHRI insight #102, our writer Cindy Benjamin takes away some of the mystery by providing an overview on Danica’s latest paper on 2,4-D and dicamba resistance mechanisms in wild radish.
In her research, Danica identified a very plausible resistance mechanism in two wild radish populations. She then went on to test the translocation theory in another nine 2,4-D resistant populations of wild radish from WA.
Danica characterised the resistance profile of the 11 resistant populations to find that resistance to 2,4-D and dicamba appears to be capped.
Looking more closely at these 11 resistant populations also revealed that while all 2,4-D resistant populations were also resistant to dicamba, the level of resistance to the two herbicides varied.This suggests there’s no consistent cross-resistance to these two auxinic herbicides within a population.
Conducting the same experiment with the radioactive 2,4-D applied to the leaves, Danica also found that translocation varied enormously both between and within resistant populations.
In fact, several of the resistant populations translocated 2,4-D just as efficiently as susceptible populations.
So, what’s going on? Click through below to find out!