Worried about lodging in malt barley?

To help manage the impact plant lodging can have on malt barley yields and quality, growers are turning to Moddus^® plant growth regulator (PGR) from Syngenta.

University of Alberta Agronomy Research Scientist Sheri Strydhorst notes that research shows lodging can reduce cereal yields by seven to 35 percent. For malt barley growers, a ripe, lodged crop is in peril when laying on the ground. “When weather events occur and the heads get wet, the seed can begin the germination process, making it unsaleable for malt. This can represent a major quality and economic loss for the grower if they need to sell into the feed versus the malt market,” Strydhorst says.

Lodging occurs with moderate to high precipitation and high fertility. It happens under growing conditions that support big-yielding crops, but it does not happen under drought, Strydhorst adds. Increased amounts of lodging can also be seen where there are insect or disease infections, increased fertilization, higher seeding rates and heavy precipitation or irrigation.

Where PGRs fit on your farm

PGRs are one of several tools growers can use to help manage lodging. A good strategy includes selecting varieties with good genetic resistance to lodging. Altering agronomic practices, including decreasing or splitting nitrogen fertilizer rates, and reducing seeding rates can also reduce lodging, but these practices can reduce yields.

Strydhorst adds, “PGRs are a great option in areas where malt barley varieties do not provide sufficient genetic resistance to lodging; they’re also a good fit for highly productive areas with good rainfall and high yield potential.”

Moddus reduces plant height

PGRs help manage lodging by altering hormonal activity, which modifies plant growth and development. Randy Retzlaff, Technical Lead – Fungicides with Syngenta, says a key feature of Moddus is inhibiting the plant’s ability to produce gibberellins, hormones that regulate stem elongation. “This promotes a stronger stem, and in some cases shorter stem, to help mitigate the plant from lodging as the year progresses,” he adds.

Strydhorst says growers can expect to see the results of PGRs 14 days after application when significant height reductions can occur — up to 6 cm. Her 2019 research showed PGR application caused significant barley height reductions of between 3 and 18 cm by the end of the growing season, compared to no PGR application. She notes that PGR applications do not guarantee yield increases, but her research team has seen five to six more bushels per acre in some growing seasons.

Wide application window

Retzlaff says a distinguishing feature of Moddus is its wide window of application, which extends from the beginning of stem elongation (BBCH 30) to flag leaf timing (BBCH 39). He notes this application window includes the peak production of gibberellins, which starts to occur at BBCH 30 to 32 (when the plant has five to six leaves with one to two tillers), making it highly effective in promoting a stronger thicker stem.

Moddus is very crop safe but there may be situations when growers should proceed with caution when using it. In drought situations, when plants are visibly stressed at the five- and six-leaf stage, growers should delay application. “Remember, you can spray safely up to flag leaf timing so growers can take advantage of that wide window.”

He also recommends applying in the morning rather than evening in cold conditions of 5C or less.

“We feel Moddus is an exciting option for growers,” Retzlaff says. “It may produce a shorter plant depending on the variety, but more importantly, it helps produce a plant with thicker stems and a stronger root system. That delivers improved standability and mitigates the effects of lodging within a field.”

While Moddus is registered on barley, it is recommended that growers contact their maltster before making a Moddus application.

Performance evaluations are based on internal trials, field observations and/or public information. Data from multiple locations and years should be consulted whenever possible. Individual results may vary depending on local growing, soil and weather conditions.