A YIELD Loss to Disease Model is being developed that will assist grain growers and consultants to select the best wheat variety and management strategies to optimise yield potential and profitability.
The Department of Primary Industries and Regional Development (DPIRD) is leading the project, with co-investment from the Grains Research and Development Corporation and several interstate collaborators.
A prototype for wheat was unveiled at the Grains Research Update, Perth, on Monday for interested parties to test and provide feedback so the new tool can be refined and expanded to barley before an official release next year.
Cereal diseases have a significant impact on production, with wheat diseases alone costing the Australian wheat industry $468 million annually in lost yield and control costs.
The new national tool draws on five years of Australian field trial data and statistical analysis, used to determine likely yield responses to various disease resistance and tolerance ratings for wheat varieties.
Variety disease ratings are expressed as susceptible to very susceptible (SVS), susceptible (S), moderately susceptible to susceptible (MSS), moderately susceptible (MS), moderately resistant to moderately susceptible (MRMS) or moderately resistant (MR).
The Yield Loss to Disease Model presents the results in the form of a graph of a yield response curve, illustrating the amount of yield lost as a result of the interaction between disease pressure and variety resistance for a selected disease.
A corresponding table is also produced, summarising the estimated yield loss in tonnes per hectare and percentage for selected resistance classes.
DPIRD biometrician Karyn Reeves said while the prototype was currently configured to five wheat diseases, stem, leaf and stripe rust, yellow spot and nodorum blotch, it would be expanded to a total of 14 foliar and root diseases of wheat and barley.
"The model has been developed so growers and consultants can make more informed decisions about variety and paddock selection, by being able to compare the likely yield responses to various resistance categories of individual diseases," Dr Reeves said.
"For example, users of the model will be able to compare the yield response to leaf rust from the wheat variety Mace, which has a MSS rating, to that of Ninja, which has an SVS rating, in a paddock with a moderate disease pressure.
"In the past growers had to guess what the yield loss to disease would be, whereas now, they can rely on scientific analysis to provide the most likely outcome."
Dr Reeves said the model was a powerful tool that clearly illustrated how influential a variety's disease resistance rating was in determining yield performance in relation to the disease pressure.
"For example, a grower might expect to lose 30 per cent of the wheat crop's yield to leaf rust for a susceptible variety but only 5pc for a moderately resistant variety," she said.
The Yield Loss to Disease Model was a collaborative project, with input from New South Wales Department of Primary Industries, the Queensland Department of Agriculture and Fisheries, Agriculture Victoria and Statistics for the Australian Grains Industry (SAGI).
Dr Reeves said users could have confidence in the integrity of the data produced by the model, which was developed from a combination of scientific field trials and empirical data from across the country.
"This is a very comprehensive project, which has involved a number of people providing data from trials across five states, as well as extensive statistical analysis to compile a robust product," she said.
Interested parties can test the Yield Loss to Disease Model by visiting the DPIRD website.