Milling wheat ‘likely to need nitrogen top-up’

Strong milling wheat and protein premiums make it an easy decision to push crops for grain quality this season – but growers should be aware of low nitrogen levels.

Washout winter and spring weather means some crops face a double challenge to achieve protein specifications. Soil nitrogen is depleted due to leaching and nitrogen uptake is compromised due to poor rooting.

Tailored agronomy

Overcoming this challenge will require some carefully tailored agronomy, says ProCam agronomist Justin Smith. Soil tests indicate nitrogen levels have been 20-30kg/ha below their usual levels in some places after all the rain, he adds.

“On top of that, root growth has been seriously compromised by waterlogging, because roots haven’t had to reach down far to find moisture.

“Not only is there less soil nitrogen available, but affected plants will also have greater difficulty accessing what’s there.”

In response, Mr Smith says these risks will need factoring into mid- and late-season milling wheat nutrition, especially if the summer turns dry. Multiple foliar-applied treatments are available to supplement soil-applied granular nitrogen, he adds.

“These range from endophyte bacteria such as Encera – which fix atmospheric nitrogen inside the plant, to Twoxo Pro which stimulates the plant to improve nitrogen uptake,” says Mr Smith.

Spray timings

For the traditional flag leaf (T2) and ear (T3) foliar nitrogen spray timings, Pro+ N-Viron PCA provides nitrogen directly into the leaf in an efficient urea form – and has other benefits too.

“It also contains pidolic acid, which helps plants use nitrogen more efficiently. Which treatments are applied and when needs to be based on individual field needs. If ever there was a year for tailored agronomy, this is it.”

If May and June turn dry and soils dry out too, this will further limit root uptake, says Mr Smith. This will hit grain protein, making foliar treatments – which don’t rely on root uptake – particularly useful.

Dry soils will also limit uptake of nutrients such as magnesium and potash, but a foliar application of Proplus Excel included at the T2 spray timing will provide both of these elements plus sulphur, explains Mr Smith.

Specific weight

“The other thing needed in milling wheat is good specific weight,” he says. “You want plump, well-filled grains.” So there are multiple reasons to protect photosynthetic green leaf area against disease, including septoria tritici, which is rampant this season.

Several popular group 1 winter wheats also have low resistance ratings against yellow or brown rust.

As well as using a triazole fungicide active against fusarium for the T3 ear spray, include a suitable strobilurin to stay on top of rust risks.

“It’s not worth missing out on the good milling wheat premiums available,” says Mr Smith. “The last thing you want is a milling variety being sold for lower-priced feed.”