Concerns about fungicide resistance in grain

There's growing concern in the grain industry about fungicide resistance. Fungicide resistance has already been observed in Europe and southern Western Australia.

Dr Rohan Rainbow, from the Grains Research and Development Corporation(GRDC), says more research into genetic resistance, rather than new chemicals, will provide the most sustainable solution to the problem in the long term.

"At the end of the day, we need to use all the different tools," he says.

"However, starting with a resistant variety is the obviously the most sustainable approach, and particularly with diseases where we're experiencing fungicide resistance, that's a really important discussion."

Diseases like stripe rust, net blotch and stem rust are at a higher risk of developing resistance to chemical control because of the limited variety of fungicides available to farmers.

Currently, there's only two types of chemicals, triazole and strobilurin, to control fungal diseases, and they both have the same mode of action.

While research overseas is focussing on commercialising other types of fungicide, farmers here are being encourage to manage fungal disease strategically.
"Principally, those two groups, the triazole and strobuilurin groups, are the ones where we have seen resistance development overseas, and we're starting to see that here with the triazole group.

"As a consequence of that, growers do need to look carefully at how they manage diseases in their crops in a sustainable way.

"And that ultimately does require the use of genetic resistance, in order to keep the inoculum levels quite low.

Dr Rainbow says cultural control, like managing the 'green bridge' (stubble and weeds that remain after summer rain), can also go a long way to stopping diseases like rust.