Australian Herbicide Resistance Initiative (AHRI) insight #102 - Digging deep into 2,4-D resistance

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!