Minimise crop stress for spring barley success

Safeguarding yield and quality will be pivotal for profitability in what could be a competitive spring barley grain market this harvest.

In particular, proactively minimising stress on the crop after the wet winter could be key.

That was the message from an industry briefing organised by ProCam recently, and featuring the company’s agronomy experts from England and Scotland.

“Spring barley needs to hit the ground running,” explained ProCam regional technical manager for East and South East England, Justin Smith. “But it’s also a crop that’s very sensitive to stress. Soils and seedbeds compromised by wet weather aren’t the perfect entry for it, and crops on heavy land originally destined for winter wheat could be hardest hit.

“Minimising nutrient stress and stress caused by poor rooting will be key.”

To minimise nutrient stresses, ProCam regional technical manager in Scotland, Alistair Gordon, urged growers to begin with soil testing that gives information on the levels of soil nutrients actually available to the plant.

“Manganese, copper and zinc are typical trace elements that need addressing in spring barley,” said Alistair. “Lack of copper and zinc can reduce yield by restricting grain numbers in ears. I’ve had situations where good doses of these have been applied, but harvest grain analysis still showed they were lacking.

“I normally add nutrition products twice – with the post-emergence herbicide and with the first fungicides – as two lower doses are better than one hit. As well as applying nutrients, I think it’s a good idea to stimulate rooting so the plant can better access nutrients and moisture from the soil.”

To boost rooting and help early utilisation of nitrogen, Alistair said he has had success with an early dose of the foliar-applied phosphite and pidolic acid treatment, Incite, with independent evaluation showing lateral root length boosted by over 40%.

“We’ve also been looking at the seaweed and amino acid-based biostimulant, Zodiac, with results showing similar root length benefits, but with amino acids providing good stress mitigation properties.

“If you find yourself with a thin spring barley crop with a poor plant stand, either from difficult seedbed conditions or a low seed rate, a biostimulant can also improve tillering, helping to fill in the gaps.

“By alleviating stress, you also aid the plant’s natural disease defences. Ramularia symptoms, for example, are triggered by stress.”

After the winter rains, Alistair said crops could be shallow rooted – disastrous if the summer turns excessively dry. “That’s when improved rooting to scavenge soil moisture becomes important. Too often, biostimulants are applied after crops are already suffering drought stress, but they need applying before then to see a benefit,” he added.

Justin Smith said applying a suitable plant growth regulator (PGR) can also improve rooting plus stem strength, although PGRs need tailoring to individual fields.

“As well as the variety’s lodging risk, factors such as fertile sites, exposed sites, and higher nitrogen (N) rates also increase lodging pressures. If applying less N for lower grain N malting markets, lodging pressure should be lower. However, later-planted spring barley can be at greater lodging risk because it races through its growth stages, creating weaker stems. Because it’s harvested later, it’s also exposed to later adverse weather,” Justin said.