Cropping

Fighting fungus

By Country News

Australian researchers have a new weapon in the fight against fungicide resistance in grain crops, with confirmation that a specially adapted approach to detection, involving cancer technology, is effective for this purpose.

Researchers at the Centre for Crop and Disease Management, a national research centre co-supported by Curtin University and the Grains Research and Development Corporation, have used digital polymerase chain reaction (dPCR) technology, combined with baiting trials, to develop an advanced early warning system that can be used to better detect fungicide resistance.

Baiting trials are field trials that can optimise the capture of fungal pathogens that show fungicide resistance.

The adapted and fine-tuned dPCR technology will enable earlier, more targeted, information to be delivered to growers so they can move faster to counteract any potential yield losses.

It has also expanded knowledge about the extent of fungicide resistance in the damaging disease barley powdery mildew, and shown that the disease is more widespread than previously thought.

According to CCDM’s Fungicide Resistance Group leader Fran Lopez-Ruiz, dPCR works by allowing researchers to collect multiple samples from a crop, pool them and then analyse fungal DNA to look for resistance mutations.

‘‘Early detection is an essential step in delivering better tools for the management of fungicide resistance, and the use of this technology, in conjunction with baiting field trials, has allowed us to not only detect resistance quickly and more effectively, but to quantify the level of resistance,’’ Dr Lopez-Ruiz said.

CCDM researcher Katherine Zulak said the research team was the first to use the high throughput dPCR technology to look specifically for fungicide resistance in the field, and the accuracy and speed of the process had exceeded their expectations.

‘‘We found the technique to be very sensitive and accurate, identifying the presence of a mutation in the CYP51 gene down to 0.2 per cent of the fungal population,’’ she said.

■A paper with the details of the dPCR research has been published in the prestigious science journal Frontiers in Microbiology and can be found at: www.frontiersin.org/articles/10.3389/fmicb.2018.00706/full