Wheat yields surpass 12t/ha in SA

At the SA Crop Technology Centre near Millicent, 20 different varieties were sown after a faba bean crop into good moisture on two different dates - April 21 and May 12 - with no artificial irrigation.

FAR Australia managing director Nick Poole, who leads the HYC Project, said because of a "softer finish than 2020", later-developing northern European winter wheats fulfilled their yield potential for the first time at the SA research site.

Winter varieties Reflection and Tabasco yielded 12.74t/ha and 12.56t/ha respectively, while coded line AGTW005 achieved 12.54t/ha.

"I believe they went so well because the 2021 season resembled northern European climate conditions - we had below average temperatures during grain fill, and not excessive rainfall resulting in good solar radiation from mid October onwards - that was the marked difference from 2020," he said.

Mr Poole said not only did early-sown longer-season European wheats do well, but also later-sown varieties.

"We think that is due to partway into October, the conditions in the Lower SE started to improve and favoured those wheats that were sown in May," he said.

"It's exciting to see this type of yield potential on mainland Australia."

"Even if it was just the exceptional seasonal conditions in 2021, feed wheats Anapurna and RGT Accroc have been achieving between 10.5-11.3t/ha since 2018.

"These are genuine plot yields from the Lower SE that show the upper range of yield potential in the region and are probably 1-2 t/ha up on what we would normally expect."

Mr Poole said the previous highest plot yields achieved in Australia, within the HYC Project, was 16-17t/ha, under irrigation in Tas.

"We have hit 10-11t/ha in Vic, NSW and SA before, but never exceeded 11.5t/ha, let alone 12t/ha," he said.

Mr Poole said it was important to note these yields would not have come close to being achieved without the appropriate disease management.

"In these higher rainfall zones, you must be on top of your diseases, otherwise you cannot get these higher yields," he said.

Mr Poole said popular French wheat variety RGT Accroc had a response to fungicides between 3-4t/ha.

"If we had not controlled disease, it would have only yielded 6.5t/ha, not the 10.89t/ha it achieved," he said.

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Of the varieties commercially available in Australia, winter feed wheat Big Red (AGFWH004718) was the best performing in both 2020 (10.94t/ha) and 2021 (11.45t/ha).

Mr Poole said while those varieties that reached more than 12t/ha were not commercially available, the trials act as a kind of "screening process, to see if there's enough potential for a breeding company to consider commercialising them here".

Mr Poole highlighted Anapurna gave higher yields sown on May 12 (11.87t/ha) than on April 21 (11.3t/ha).

"With the second sowing date on May 12, Rockstar significantly outyielded all other spring milling cultivars, but its overall yield was about 2t/ha or 19 per cent lower yielding than Anapurna sown at the same time," he said. "If Anapurna feed wheat was priced at $275/t then Rockstar would have required a $57/t premium to achieve the same margin using the yield differentials in the trial.

"With the earlier sowing where Big Red achieved 11.45t/ha, the premium necessary to match the output would have dropped to $45/t (assuming quality could have been achieved with the milling wheat).

"Protein levels (11pc-plus in most varieties) and test weights would indicate that optimum yields were generated with the level of nitrogen applied (120 kilograms of N/ha)."

Canola yields of nearly 6.5t/ha have also been achieved at the SACTC.