Grains Research and Development

Date: 23.03.2011

Powdery mildew survey seeks SA barley grower input

Powdery mildew survey seeks SA barley grower input

South Australian barley growers are being urged to help in the fight against fungicide resistance by participating in a survey assessing resistance in the damaging barley disease, powdery mildew.

Hundreds of samples of the disease are needed from SA and Western Australian growers for the Grains Research and Development Corporation (GRDC) funded survey.

Australian Research Centre for Necrotrophic Fungal Pathogens (ACNFP) director and GRDC western panel deputy chairman Richard Oliver said the samples would reveal fungicide resistance patterns, and help breeders produce new barley varieties resistant to powdery mildew.

The survey follows confirmation last year of triazole resistance in barley powdery mildew – Blumeria graminis hordei (Bgh) – Australia’s first case of a broadacre crop pathogen resistant to fungicide.

Barley powdery mildew causes annual losses of $39 million to Australia’s barley crops, with most losses incurred in WA.

Professor Oliver said the survey results would help fine-tune advice to growers on which fungicides were still effective against the disease.

“The survey will also provide information about different virulence genes expressed by the powdery mildew pathogen,” he said.

“This information will guide plant breeders’ selection of genes resistant to powdery mildew, which could result in new barley varieties with improved resistance to the disease being made available in the next two to five years.”

Professor Oliver urged growers to contact him via email on Richard.Oliver@curtin.edu.au if they noticed barley powdery mildew, probably initially on volunteer barley crops.

“We would like growers to tell us what variety of barley was planted and if a particular fungicide was used,” he said.

Professor Oliver said growers could protect barley crops from powdery mildew and limit the spread of resistant powdery mildew strains by controlling barley volunteers, growing barley varieties resistant to the disease and using effective fungicides.

“Tebuconazole and propiconazole – the active ingredients in Folicur® and Tilt® respectively – have been compromised,” he said.

“We instead recommend that growers use newer triazole fungicides and fungicides with alternative modes of action including Amistra Xtra® (a mixture of triazole and azoxystrobin); Opus® (epoxiconazole); Opera® (a mixture of pyraclostrobin and epoxiconazole); or Prosaro® (prothioconazole).”

Ends

CAPTION: Australian Research Centre for Necrotrophic Fungal Pathogens (ACNFP) director and GRDC western panel deputy chairman Professor Richard Oliver.

Editor’s notes:

• Further comment is available from Professor Richard Oliver on 0414 305 999 or email richard.oliver@curtin.edu.au

• GRDC Project Code: CUR00010

• www.grdc.com.au

• This media release and other media products are available via www.grdc.com.au/media

GRDC Project Code CUR00010

Region North, South, West