A SUITE of new research projects are aimed at supplying growers with region-specific agronomic packages able to support top-quality grain production while giving growers the confidence to pursue AWB premiums.
Four related initiatives, supported by growers and the Federal Government through the GRDC and conducted by WA Department of Agriculture researchers, target agronomy in the north, central, Great Southern and south coast areas.
Findings to date
Experiments in the Great Southern have discovered that late season (at booting or anthesis) nitrogen applications seem only to bolster grain protein levels when coupled with soaking rains, and so are a riskier proposition than applications at seeding.
If backing up after a canola crop, these nitrogen applications must be applied at 10-20 per cent higher rates to obtain protein levels above 9.5 per cent.
Meanwhile, to keep screenings under control, nitrogen should be applied only to soils with appropriate potassium levels (of at least 70 parts per million).
But while nutrient management is integral to grain size, variety is also important for growers hoping to minimise screenings.
"While Karlgarin, Cunderdin, Tincurrin, Cadoux and Janz generally produced smaller grains because of their physiological characteristics, their shape also exposed them to high screenings," said program leader Wal Anderson.
"For example, Arrino, which produces grain of a comparable weight to Cadoux, had lower screenings because its diameter helped it to stay above the 2 mm slotted screen."
Arrino also avoided high screenings because the plant developed shorter ears, but populated them more heavily with grain. When placed under moisture stress in dry seasons, Arrino produced fewer grains but filled them to an even weight. Similar trends emerged in the northern wheatbelt where H45 produced more grains per ear, anticipating a sound finish to the season, but then struggled to fill these grains under moisture stress, while Westonia adopted the Arrino strategy.
Although south coast trials have confronted dry conditions, Wyalkatchem has combined high yields and falling numbers with good resistance to leaf and stem rust to emerge as the best early-season sowing option. This result has been confirmed for most other parts of the state.
Two eastern states varieties, H45 and Mitre, proved the best late and midseason options, respectively, with competitive yields and good rust resistance on the south coast.
"The findings of these regional projects will form part of our total statewide agronomy investigation," Dr Anderson said.
"These projects are still progressing and will be joined by new studies in, for example, the central wheatbelt, to test current local and interstate varieties and stage four breeding material.
"Susceptibility of varieties to pests and diseases and the effect of management packages on processing qualities for end users will also be closely monitored."
Program 1 Contact: Dr Wal Anderson 08 9892 8412
North, South, West