The highest rating for Septoria on the recommended list is held by breakthrough milling wheat variety Extase. Lucinda Dann met a Herefordshire grower to find out his experience of growing it in the west.

New winter wheat variety Extase could be a useful tool for growers in the west in managing their spray programmes, but drilling early will undermine its resistance to septoria.

The group two milling wheat is likely to appeal to growers in the wetter west: with a rating of 8.1, it has the highest resistance to septoria of all the varieties on the recommended list.

See also: Tips on managing blossom midge in wheat

Added to that, it has a good specific weight, good straw strength and an eyespot rating of four on limited data, making it a good all-rounder.

Natural resistance

Independent agronomist David Lines says that its selling point for growers in the west should be the ability to leave it until last in spraying programmes, relying on its natural resistance.

“What Extase will do is buy you more time, so that you can spray other varieties,” he says.

“You could spray all the varieties being grown with one tank mix, but put Extase last.”

Mr Lines is advising on 32ha of Extase for Herefordshire grower William Layton, who farms at Ivington, near Leominster. The crop is grown on a seed contract for Wynnstay.

Mr Layton grows 283ha of combinable crops, and lets 36ha of land for potatoes, in addition to 445ha of permanent grassland.

Alongside Extase, he is also growing Kinetic, Graham, Costello and Shabras on seed contracts.

Although Extase shows only a 0.5t/ha difference between treated and untreated yields, it is not an opportunity to cut inputs drastically; rather, growers should tailor their spray programme to maximise margins.

“I wouldn’t advocate not spraying it. I’m worried that people will grow Extase and not spray it and break it,” says Mr Lines. “It’s not about saving money, it’s about the best returns.”

He suggests that if growers want a low-input variety for earlier drilling, they should consider Graham instead.

Late drilling

Growers on the west side of the country typically drill early to avoid the risk of not being able to travel later in the season, which is why early variety Grafton has always been popular in the area.

But growers looking at Extase as a possible replacement for Grafton (which is ideal for early drilling and harvest) will be disappointed. The variety does not like being planted early as it produces a lot of biomass.

Gareth Bubb, commercial technical manager at Bayer, says: “Extase has a big biomass, it was 10cm above everything else in the last week of March.

“In north Herefordshire, a good 50% of crops are in the ground before the end of September.

“But when you put things in a bit earlier you get more biomass, and with higher biomass comes more disease.”

Although it brings a higher risk of disease, a big biomass has also been shown by the Yield Enhancement Network (YEN) competition to produce the highest yields.

“If we can maintain the biomass, it should yield well. All the crops with 700-plus ears did the best in the YEN,” Mr Bubb adds.

Gravity compared with Extase

Comparing a crop of Gravity with a crop of Extase (drilled within two days of each other, on 23 and 25 September) Extase was 15-18cm taller in the last week in March, despite there being little difference in their overall height at harvest.

It was also a full growth stage ahead, with leaf three emerging (GS32), compared with GS31 for Gravity.

The crop was not as clean as might be expected, given its rating for septoria, with disease present on leaves 6 and 7 and tipping on leaf 5.

“My gut feeling was that we wouldn’t see any disease, but it is cleaner than Gravity,” says Mr Lines.

Eyespot was also present at the base of the stem, but had yet to penetrate any leaf sheaves.

However, because of the 23 September drill date, the Extase is likely to be performing more like a 7 than an 8.

“It’s going to have more in it than something that was drilled in October. Dirtier varieties sown later will be cleaner,” says Mr Lines.

“It’s not an early driller, it wants to be late September or early October, but people might see the rating and want to put it in early.

“If the AHDB Recommended List were based on a mid-September drill date, then all the varieties would be 1-1.5 points lower.”

Weeds

Mr Layton has normally finished drilling by 10 October. He started drilling earlier in order to cover his increasing acreage, and letting his potato land means he can plant earlier and in better conditions.

Although early drilling is currently the norm, Mr Bubb thinks that the increasing number of weeds seen in the area means growers are likely to progress to later sowings.

He says that he is still seeing fields in Herefordshire full of blackgrass, and there is more and more ryegrass and brome appearing as a result of min-till and less-diverse rotations.

Mr Bubb thinks the best way to lower the risk that growers will not be able to travel later in the autumn is to have a greater range of machinery.

“I would say that if you are going to invest in farm kit, buy another drill. We haven’t got the big kit round here because of the smaller field size, so getting two would be a good investment.”

Cost-effective options

While there was lots of disease early on this season, the dry spell in February means crops were looking very clean at the end of March, prompting Mr Lines to decide to miss out applying a T0 to any variety rated 6.5 or higher, including Extase.

Owing to it’s high resistance, Mr Lines would generally recommend an azole + chlorothalonil at T1 for Extase, followed by a potent SDHI at T2.

This year, he recommended 1.0 litres/ha of SDHI Aviator (prothioconazole + bixafen) +CTL at T1 as a wet early April spread more disease, and will be putting on 1 litre/ha of Ascra (bixafen + fluopyram + prothioconazole) at T2 if the weather remains bone-dry, as he is hoping to push the crop as hard as possible.

Last year the deep soils didn’t dry out over the hot, dry summer and Mr Layton achieved 11t/ha for his wheat crops.

Mr Lines believes Aviator is now fitting as a cost-effective T1 product, as it is not a lot more expensive compared with the same rate of azole Proline (prothioconazole) + chlorothalonil.

“If you look at an azole, it’s not a lot cheaper – so you might as well put an SDHI on,” he says.

“Even if conditions are really good, what else is the chemistry doing in terms of retaining green leaf and for water absorption.

“If leaf 5 stays green, then it is still photosynthesising rather than respiring.”

By comparison, the Gravity crop, which is on soil that averages 11-12t/ha, will receive an SDHI at both T1 and T2.