Why it may be time to drop susceptible winter wheat varieties

Winter wheat varieties that are susceptible to disease need not feature in cropping plans for harvest 2024, except where growers are targeting the Group 1 breadmaking sector, according to crop experts.

After a difficult year for controlling septoria, coupled with spiralling fungicide prices, the advice is to move on from varieties with lower ratings and reduce the risks and costs associated with their production.

Varieties with combined ratings of less than 6 for septoria and 8 for yellow rust should be replaced by more recent introductions with better scores, they suggest.

See also: What’s in Your Fertiliser Shed? Grower favours solid nitrogen for milling wheats

Out of the top five winter wheat varieties – which account for 50% of the country’s wheat area – just Extase and Dawsum make this cutoff, while Skyscraper, Gleam and Skyfall all come below it.

When those disease standards are applied across all 39 wheat varieties on the AHDB Recommended List (RL), it selects 15 of them – narrowing the field considerably, but still giving enough choice.

Other agronomic characteristics that also warrant closer inspection include lodging scores and grain specific weight values, as neither have been given much of a test in the past couple of seasons.

Group 1

The exception to this disease-rating rule is the Group 1 market sector, where newcomers are sorely needed. Zyatt was the last variety to be added to this category in 2017.

As a result, the four quality varieties all have known weaknesses.

Crusoe is the oldest variety in this group, and does meet the above septoria and yellow rust targets, with 6.2 and 8, respectively. However, with its brown rust resistance of 3, it requires vigilance.

Crusoe remains popular with farmers and millers alike. It is recognised for better conversion of nitrogen into grain protein and a greater ability to achieve the full milling specification.

“Crusoe’s grain quality and yield remain,” says Duncan Durno, arable technical manager at Openfield. “It’s the easiest of the Group 1s to get protein into.”

Growers who are confident of managing Skyfall and Zyatt should stick with them, he suggests.

“Yellow rust is the main problem in the Group 1 sector,” says Niab cereal varieties specialist Clare Leaman.

“Zyatt and Skyfall both have a rating of 3, so the enthusiasm for growing them is wearing a bit thin.”

If falling nitrogen prices and better premiums tempt some Group 1 growers back into the fold, Crusoe will have a role to play and it can be used to manage a Group 1 portfolio, she notes.

Skyfall has good market share, is still grown as a second wheat and in later drilling situations, especially where blackgrass levels remain difficult, notes AHDB’s senior field trials manager Mark Bollebakker.

“Zyatt’s septoria rating of 6.1 has been appreciated this year,” he adds.

Group 2

In contrast, all five of the currently recommended Group 2 varieties meet the minimum disease rating test, showing good resistance to septoria and yellow rust.

New to the sector this year is Ultimatum, which comes in just behind Extase with a yield of 101%.

Many other agronomic characteristics, including a 6.4 septoria rating, are also behind those of the popular front runner.

A slightly higher specific weight and good resistance to sprouting will help its cause, but more information is still needed on whether Ultimatum will be included in Group 1 contracts.

“We know quite a lot about Extase now and it’s widely grown,” adds Clare.

“It’s a fast- developing variety, which seems to suit no- and low-till situations, and there are some Group 1 contracts being mentioned.”  

Palladium’s suitability for Group 1 markets will only be confirmed after harvest, so that remains an unknown.

It is described as a respectable variety which can be drilled earlier than Extase, making it a good partner.    

“It’s the earliest maturing of the group and brings a 7.4 rating for septoria and a 9 for yellow rust,” says Mark.

Mayflower, on a lower yield of 97%, has the best septoria rating of 8.9, along with a 9 for yellow rust, he notes.

Group 3

Described by some as the headache sector, Group 3 varieties have failed to catch the imagination in recent years and a shake-up is overdue.

The new one in this group is Wilkinson on 101%, which is suitable for export and distilling and has good straw characteristics, but is later to mature and has a lower specific weight of 75.4kg/hl.

It also has a septoria rating of 5.5 and a yellow rust score of 7 – putting it below threshold levels.

The only Group 3 variety with any following is Astronomer, which is also suitable for distilling. But with Cougar in its parentage, there is a lingering fear about septoria, even though it has a 6.2 rating.

Group 4 soft

Redwald has come onto the AHDB Recommended List with a very high yield of 107% and an untreated yield of 92%, capturing the imagination, notes Clare.

“It has huge yield potential” she acknowledges. “It also has a 7 for yellow rust and a 6.7 for septoria, as well as orange wheat blossom midge resistance.”

However, a lower specific weight and a rating of 5 for straw strength – the lowest on the RL – are less convincing.

Mark agrees with Clare’s summary: “It’s about having a management plan for a variety like this. It will have to be drilled later and at lower seed rates on less fertile sites.”

The other new soft feed variety is Zealum, which has a yield of 103%.

“It’s very different to Redwald but matches its yield performance when drilled early,” points out Duncan. “It’s safe and steady in comparison, so shouldn’t be overlooked.”

With better lodging scores and a 9 for yellow rust, Zealum’s septoria rating of 5.8 is less appealing, he admits.

The other soft Group 4 which is expected to sell well again is Skyscraper. “It has been very consistent but it does have its risks,” says Duncan.

Skyscraper is weak on septoria with a 4.9 rating, so loyal growers could look at other options now.

Bairstow and Stokes both have better septoria ratings, but are later to mature and their lodging scores means their management has to be considered, he says.

Group 4 hard

Last year’s arrivals, Champion and Dawsum, continue to create headlines in the hard feed sector and both varieties have taken significant market share.

Champion heads the list with a yield of 106% and a high untreated yield of 93%, reflecting its very good disease resistance which includes an 8.1 for septoria.

It does, however, have a lower specific weight of 75.5kg/hl and a moderate score for straw strength, so may have to be drilled later.

Dawsum already accounts for 15% of the wheat area in England, reveals Duncan. “It’s been taken up and has a specific weight of 80kg/hl, which is only beaten by Costello.”

A septoria score of 6.4 has been questioned this year, with more septoria being seen in what has turned out to be a high pressure year, admits Mark.

“That may be because Dawsum was drilled earlier than ideal in some situations – time will tell if its rating needs to change.”

The only newcomer is Oxford, which was recommended for the East and West, with a yield of 104%.

It brings good disease-resistance ratings, plus orange wheat blossom midge resistance, but is another with a lower specific weight.

“It’s not clear what Oxford brings over the existing choices,” says Duncan.

Other popular hard feed varieties include Graham and Gleam, although their disease ratings are coming under pressure now, and Costello for its highest specific weight.

Typhoon, which joined the list last year, is a slower developing type with excellent yellow rust resistance and a 7.3 for septoria.

A disappointing yield performance in trials last year has seen it relegated on the list, but it may suit early drillers.

What about pests?

The role of RAGT’s Gensurus wheats, which bring both resistance to barley yellow dwarf virus (BYDV)-transmitting aphids and orange wheat blossom midge, in reducing or eliminating insecticide use could be important.

Seed of Grouse, a hard feed wheat, is available for this autumn, despite the variety not featuring on the Recommended List (RL). The breeder’s information suggests that it has a 5 rating for yellow rust and a 5.5 for septoria, along with a +2 for maturity.

Such is the demand, it could account for almost 2% of the market, says breeder RAGT, as it allows growers to drill early without worrying about aphid migration and possible virus transmission.

RAGT managing director Lee Bennett says the decision to withdraw it from the RL system was taken because the agronomy protocol used in the official trials doesn’t allow varieties such as Grouse to express their full potential.

“We know that growers want to stop using insecticides and with policy starting to reward that, Gensurus varieties are going to find favour,” he says.

A milling wheat, with both orange wheat blossom midge and BYDV resistance, is in the company’s pipeline, he confirms.

Grower intentions

In Cambridgeshire, James Peck of PX Farms is weighing up whether to stick with Skyfall, which all went for milling last year, or switch to a hard feed variety and reduce the farm’s greenhouse gas emissions.

With 1,500ha of milling wheat currently in the ground, he is pushing ahead with a carbon scheme that will reward him for climate-friendly farming practices from September, so he is questioning fertiliser use.

“Getting an income from carbon may mean that I will be better off growing feed wheat and using less nitrogen, rather than growing milling wheat with its higher fertiliser requirement.

“If I stay with Group 1s, I’ll stick with Skyfall, as we know how to grow it,” he says. “But I will also try an alternative feed variety on a trial area for comparison.”

In Oxfordshire, Stephen Goodwin is growing Extase this year, but plans to go back to growing a blend of varieties next year, for the diversity benefits and lower disease pressure that it brings.

The blend is going to feature Extase, Dawsum and Skyscraper, he reveals, but he will also keep an area of Extase, as he finds it works well in a direct-drilled situation.

Most of his winter barley is Tardis this year, but he is toying with the idea of growing a hybrid where blackgrass is an issue.

“There’s one coming along with BYDV tolerance, so that’s of interest.”

In Bedfordshire, Andrew Robinson of Heathcote Farms is sticking with milling wheats, with his whole wheat area being Group 1 and 2 varieties.

Andrew Robinson © Tim Scrivener

He has chosen Extase, Crusoe, Palladium and Illustrious, and will also try a blend of milling varieties, following a trial of three blends this year.

Andrew conducts extensive farm trials with varieties and treatments and saw an average 3.9t/ha response to fungicides last year.

While Extase gave a treated yield of 12.7t/ha, its untreated yield of 12.1t/ha meant that the variety gave a 0.6t/ha response.

In sharp contrast, Zyatt gave a treated yield of 12.5t/ha, but an untreated yield of 3.6t/ha – resulting in a whopping 8.9t/ha response. 

His winter barley variety choices will be Tardis and Bolton, having moved away from hybrids due to their higher seed cost and volunteer problem.