It is rare to extol the virtues of Scottish weather, but this year the region’s cereal growers have escaped the UK’s worst winter conditions.

Storms Jorge and Dennis made February one of the wettest on record, but still nothing like the four-fold rise in average rainfall in parts of England and Wales, leaving crop prospects better than much of the UK.

In Lothian and the Borders, Agrii agronomist, Greig Baird, said 75% of his winter wheat and barley should yield respectably. “There’s a big tail and a call needs making on some backward crops. But forward ones look promising and with careful management and reasonable weather should perform well,” he told The SF.

Nutrient tissue testing tops his priorities, especially in stressed forward wheats. Although soil sampling might show availability, shallow roots may not have picked nutrients up.

“Although many have had up to 120kg N/ha, this and a number of trace elements might not have been absorbed. Potash, zinc, copper, manganese and magnesium could be short too. Ahead of T1 sprays, I would suggest further tissue tests as a precaution.”

In contrast, backward crops have just started tillering and have only received a single N application, typically 60kg N/ha. Applying a similar amount soon will further aid rooting and tiller survival.

Forward crops had a PGR with T0 sprays, but more is warranted and essential in late drilled crops. “When these crops start rapid growth apical dominance will be an issue, with shallow rooting adding to lodging risk,” he said.

“It will be important to encourage root structure. December and January drilled crops weren’t rolled so early soil to root contact was impaired. Typically, use a chlormequat (3C) and Alatrin Evo (trinexapac-ethyl) mix.”

Cool easterly winds have dried mildew and yellow rust in winter wheat, but he had seen some old mildew pustules, but few active spores. Yellow rust is largely confined to lighter, coastal soils.

He planned to check both diseases at T1 with Boogie Plus (prothioconazole + bixafen + spiroxamine), with multi-site protectant and rates adjusted to septoria severity. “The spiroxamine will keep a check on yellow rust and mildew. Generally, crops are carrying less septoria than usual, which offers a degree of rate flexibility based on variety resilience and drilling date.

“Where a T0 wasn’t possible it might be worth keeping T1 rates higher,” he added.

Bayer’s Craig Simpson suggested eyespot should be factored into T1. Of the soft Group 4 wheats that dominate the region, only Revelation scores over five.

“Ratings have slid over recent years and most soft feed wheats are rated four, septoria resilient Sundance just three. It’s worth building in some protection at T1, and with its prothioconazole loading products like Boogie Plus or Ascra (prothioconazole + bixafen + fluopyram) are good choices,” he said.

He also stressed the importance of timing, but especially given such a range of drilling dates. Leaf three emergence could be earlier in later sown crops as they race through growth stages.

In Lothian and the Borders, Mr Baird said winter barley was carrying more disease. Rhynchosporium and mildew are easily found, with net blotch in some crops. Trifloxystrobin will partner an azole + SDHI + multisite mix to boost rust and mildew control.

Brown rust in hybrid varieties is a key issue, with only Belfry rated over six. Mr Baird was surprised by levels in some varieties so early. “I think it shows how mild the winter has been in places.” Propel (prothioconazole + bixafen + spiroxamine) is the likely go to product as spiroxamine will help check brown rust. He expected growers to add CTL to T1 sprays if they had stocks.

That might aid early suppression for ramularia, with continuing crop stresses possible, although T2 is a better timing for ramularia control.

Professor Fiona Burnett, of SRUC, wasn’t overly concerned with levels of brown rust at this point. She said it was down to a mild winter and expected an effective T1 mix to deal with the infection that is there.

She pointed out that despite disease often being seen in winter barley, fungicides offer good control and it rarely developed into a significant threat, reminding growers that CTL usage is restricted so the same product can’t be used more than once up to GS32, and more than 2000g in total shouldn’t be applied.

Mr Baird is looking out for grassweeds, too, in both October and late-drilled crops. Many had no autumn herbicides, raising spring weed pressure.

The cut-off date and product choice in winter barley may have gone, but not for wheat. “Despite a heavier burden this season, meadow-grass control with a spring herbicide such as Pacifica Plus (mesosulfuron-methyl + iodosulfuron-methylsodium + amidosulfuron), is achievable. The key is timing and favourable temperatures.

“Despite slow germination, it develops tillers quickly, making control more challenging,” he noted.

Angus crops more even

The crop picture in Angus was more even, with Agrovista agronomist, John Murrie, saying 85-90% of winter crops had reached spring with respectable potential.

A key difference was the lack of brown and yellow rust. So far, hybrid winter barley is brown rust free and yellow rust isn’t a concern in any wheats, although he guarded susceptible varieties with a rust-active T0, such as Alto Elite (chlorothalonil + cyproconazole).

In winter wheat, septoria in lower leaves is not unexpected, given the mild winter and the popularity of Barrel, Elation, Skyscraper and Jackal, which could be September or October sown. “Our weather means there is little choice when it comes to drilling – if the conditions are good, you have to go,” he said.

T1 strategies will match crop development and potential. Crops showing promise and a little further forward will get an azole + SDHI + CTL mix, but those drilled later might get Opus (epoxiconazole) or Proline (prothioconazole) + CTL, with yellow rust susceptible varieties having the addition of a strobilurin fungicide, or Nebula (boscalid) if eyespot is a concern.

“T0 sprays will have kept a lid on septoria and yellow rust, and where disease pressure is lighter you don’t always need a primary SDHI at T1,” he commented.

There is less room for compromise here and an azole + multisite mix could ‘run out of steam’, he warned. If the gap to T2 gets stretched, disease pressure in wheats could change.

“We don’t have the cultural option of late drilling and Scottish markets don’t suit varieties with better septoria ratings. An SDHI offers slightly better persistence.”

For winter barleys, tiller protection meant an azole + SDHI mix was essential. He will add an SDHI to Jaunt (prothioconazole + fluoxastrobin + trifloxystrobin). Rhynchosporium is the key target.

He will also tissue test for nutrient uptake. “Deficiency in one nutrient can impair the uptake of others. That’s why root structure at depth is so important. If you’re short somewhere you risk putting plants under stress,” he argued.

He included amino acid biostimulant TerraSorb Foliar Extra into wheat and barley T0 sprays, and planned more at T1 in late crops. He said their stress busting properties have a place: “Our extensive trials had shown amino acids helped in stress situations. They enhanced nutrient uptake, root development and photosynthesis.”

T0 sprays included PGR Canopy (mepiquat chloride + prohexadione calcium) and crops also got Moddus (trinexapac-ethyl) + 3C at T1.

He feared a late flush of grassweeds, cleavers, chickweed and volunteer OSR, so will probably opt for Whorl (halauxifen-methyl) or Nevada (florasulam + fluroxypyr). But he urged care: “It has been dry and quite windy, which might have dewaxed leaf surfaces. Any T1 mix that is a bit hot could induce scorch.”

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