EXPERTS are calling for more disease-control measures to be included in National Variety Trial comparative yield experiments.
In an informal poll at a recent Grains Research and Development Corporation forum in Ballarat, agronomists and plant breeders voted overwhelmingly to support of the use of fungicides on varieties susceptible to disease in the NVT program.
AGT wheat breeder Russell Eastwood said the GRDC had long-banned the use of fungicides in comparative trials, fearing it would encourage the widespread use of varieties susceptible to disease.
Dr Eastwood said although a small number of trials used fungicides last year, there needed to be more widespread use to provide data useful in the real world.
JSA Independent agronomist Kate Burke said the NVT data produced on wheat and barley trials included no information on what diseases were present at individual sites.
Ms Burke said interpreting the data from NVT trials not incorporating fungicide use was "fraught with danger".
Dr Eastwood said the NVT trials should be managed to reflect the disease management a farmer would normally practise on his own farm.
He cited the example of the wheat variety bolac, which was resistant to stripe rust, while chara was prone to attack from the fungal disease.
"If you run trials without disease control, chara will yield less," Dr Eastwood said.
"It hasn't told you that bolac is higher yielding; it's told you bolac will yield more (than chara) if you don't control the rust in chara."
Dr Eastwood said persistent rain last year meant there were high levels of rust disease in wheat crops, which had an impact on NVT trial data.
"In a year like last season, the yield data is so driven by rust reaction, it is questionable how valuable the data actually is," he said.
Dr Eastwood said data from the NVT program in the Western District showed oxford was a much higher yielding variety than gairdner.
Gairdner suffered from barley scald and growers would normally spray to control the disease, whereas oxford was resistant to the disease.
He said the NVT trials suggested oxford was a much superior variety to gairdner - which he doubted.
GRDC manager responsible for the NVT program Juan Juttner said when the system was set up, growers did not want spraying of fungicides in the trials.
Dr Juttner said grower opinion on the use of chemicals in trials varied markedly between states.
"The GRDC is in a difficult position," Dr Juttner said.
He said the decision on whether to spray fungicides would be left to new advisory committees of farmers and agronomists, which were currently being set up.
He said the Victorian committee would be set up by mid-March and the decision would be left to it.
Dr Juttner said about 20 per cent of trials currently included spraying.
