GRAIN growers facing problems with weeds in barley could soon have a new management option.

Now in the final stages of field evaluation and commercialisation by AWB Seeds, imidazolinone-tolerant barley has been developed through conventional plant breeding techniques by the Victorian Department of Primary Industries.

All that is needed is approval for the post-emergent use of an imi-group herbicide, which could be registered by the Australian Pesticides and Veterinary Medicines Authority this year.

Birchip Cropping Group consultant agronomist Dr Kate Burke said this would allow growers access to the new cultivar, VBHT805, which has been named scope, as soon as next year.

Dr Burke said BCG trials had found imi-tolerant barley had the potential to be used as an alternative to clearfield wheat or clearfield canola, to manage brome grass, wild oats, annual ryegrass and volunteer wheat.

Many dry-sown barley crops were contaminated with volunteer wheat last season, but there is not yet an in-crop herbicide option for safe use in barley.

One of the BCG trials was carried out near Woomelang last year, where there was little brome grass, but some volunteer wheat.

A knockdown herbicide was applied before sowing of scope barley on May 14, at a rate of 50kg per hectare.

Fertiliser included 55kg/ha monoammonium phosphate at sowing and 26 kg/ha of nitrogen applied as liquid urea and ammonium nitrate at growth-stage 32.

Dr Burke said treatments were monitored for plant emergence, herbicide effect on crop and weeds, final weed densities and grain yield.

Broadleaf weeds were controlled with a broad-spectrum herbicide mix.

There were no significant differences in grain yield and grain quality was good.

But Dr Burke said wheat contamination in grain samples from harvest differed significantly between herbicide treatments.

The nil-herbicide, pre-emergent metribuzin and post-emergent metribuzin treatments had wheat levels exceeding the receival standard for malting barley, of 85 wheat grains per 500ml.

"All the imi-herbicide treatments were free of wheat, indicating complete control," Dr Burke said.

AWB Seeds manager Simon Crane said scope was under "seed increase" and should be available for commercial production next year.

BCG extension manager Fiona Best urged farmers to attend the BCG members-only trials review day at Birchip on Friday.

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