Growers should place the same refinement on spring barley variety choices as other agronomic practices – that’s the view of Scotgrain’s specialist, Don Peters.

Advances in diagnostic and sensing technology has given growers further insight to help them refine agronomic strategies. But when it comes to variety choices, it is largely unchanged, with growers often making decisions on those with the best gross output scores – or the left-hand side of the RL, as he described it.

He believed growers should dig deeper when looking at variety options, especially when it comes to malting choices.

The key to sustained spring barley success, ha argued was down market robustness – varieties that consistently deliver malting spec' season after season.

That’s why he was happy to recommend Diablo over recent additions such as Skyway, Tungsten, Splendor and Firefoxx. “Although these varieties have better output potential, they haven’t proved so consistent in terms of quality,” he noted.

He picked up the potential of Diablo early on through their early evaluation programme (EEP). Scotgrain take all NL and candidate varieties through their own five-year assessment programme, starting with strip plot trials and micro-malting, and the most promising lines going through to farm trials and macro-scale evaluation with key distilling customers.

"What we’re looking for is those varieties that are best suited to meeting contract volumes and doing so consistently. We take the varieties with the better yields and agronomics and then quality test them across all parameters as a commercial crop would be,” he said.

The work has found that some on the RL list with full malting approval aren’t ‘universal’ in their suitability. Equally, some considered poorer in terms of quality, perfectly suited niche, or regional demands.

He considered EPP data crucial, with end markets so important these days. As varieties progress through the EEP process, so the tonnage increases, which means increased trials.

“The benefit is that as we need more grain so the trial area spreads. It means we know which varieties suit regional demands. It gives us confidence in their marketability, the specifics of which can be passed onto growers," he pointed out.

"Our data doesn’t form part of the RL list but it is another layer of data to refine variety choices.”

Of the newer varieties on the list, he felt that Tungsten and Firefoxx had potential. He said growers shouldn’t overlook them, but need to understand that they might not be appropriate to every market requirement.

“We still have them under evaluation and they can go on to be highly marketable varieties. It is just at the moment they don’t have the same consistency as varieties like Diablo, Sassy, or Laureate.”

The EPP process has also puts variety agronomics in the spotlight, particularly disease ratings. He believed with barley diseases being seasonally more variable than those found in wheat, it has possibly handicapped breeders in developing better agronomics.

The result means disease control is more dependent on fungicides. That is reflected in a look over the barley RL list.

Of the newer spring barley additions, only Firefoxx gets a 5 for rhynchosporium and all are susceptible to brown rust.

Winter varieties Bolton and Bordeaux get a 5 and 4, respectively, for rhynchosporium but both have a susceptibility to net blotch and brown rust. Tardis fares a little better, with a 7 for rhynchosporium and a 6 for brown rust.

For colleague, Neil Millar, disease ratings are a concern. There isn’t really the option of a low input programme, such that Extase or Theodore offers in wheat.

“We need to maintain the programme approach, including the use of a T0 in winter crops, especially if mildew is a concern. The economic benefit may not be as strong as other timings, but it is setting the crop up, and helps manage disease pressure and induced stress later in the season,” he said.

Poorer disease ratings for newcomers to the list also come with the loss of CTL (clorothalonil), a product that he felt covered some shortcomings in the fungicide armoury.

Fortunately, azoles in combination with SDHIs, or strobs, or spiroxamine are still working well against rhynchosporium. For ramularia although prothioconazole and bixafen are still effective and the arrival of mefenttifluconazole + fluxapyroxad helps, neither are as good as Bravo.

To offset the reduced activity of folpet and varietal susceptibility, he said growers might need to adjust rates, especially this season with many winter crops well established after an open autumn.

“Propel (prothioconazole + bixafen + spiroxamine) is a popular barley choice. In the past, rates have typically been 0.4-0.6 l/ha but instead we are now looking at 0.6-0.8 l/ha, depending on variety and risk.”

With disease control still reliant on fungicides he said growers should do all they could to preserve crop health. He wanted to see comprehensive soil and tissue testing to check for deficiencies in both macro and micro nutrients.

“We need to have a balanced approach as even a small nutritional deficiency can lead to a compromise in health,” he argued.

As well as adding trace elements to main fertiliser and foliar applications, he urged growers to consider nutritional seed dressings, along with routine seed dressings.

Another consideration was the physiological benefits of SDHI fungicides. He felt their drought and greening benefits are a way of reducing plant stress.

“All crops benefit from a planned nutritional and disease control programme, helping to convert the potential of the seed into the maximised saleable crop,” he said.

Bayer’s Grant Reid said physiological benefits played a part last season. He pointed to yield responses in Bayer trials with septoria resilient wheat varieties like Extase and Graham.

“When your seeing 1.0t/ha responses with Extase and Graham when septoria was almost non-existent it shows something else is going on. Our Xpro range have various chlorophyll and rooting claims on their labels,” he said.

Evidence that he is right comes from NIAB trials with the first of those Xpro fungicides, Aviator (prothioconazole + bixafen). NIAB simulated drought conditions to look at moisture uptake. What they found was that SDHI treated plots had a better root structure ensuring better water uptake at depth.

The same trial also showed improved photosynthesis in drought conditions which NIAB researchers put down to plants being less stressed. “The view is that leaves and stomata stay open for longer, aiding transpiration and photosynthesis.”


Check malting association approval

Bayer’s Grant Reid said malting barley growers need to check product restrictions before making fungicide decisions.

He pointed out that actives have limitations on their use imposed by the Maltsters Association of Great Britain (MAGB). One of those being fluxapyroxad.

“The MAGB have only granted the use of fluxapyroxad in malting crops until GS45. Use beyond this point on a malting crop and it could well be rejected.

"A better option might be to hold off and to include another multisite option such as folpet, in with Siltra (prothioconazole + bixafen) as both are still offering something against the disease and can both be used past the GS45 point,” he suggested.