Saskatchewan Agriculture held their annual Agronomy Research Update this week.
One of the presentations was from Mike Hall at the East Central Research Foundation.
He talked about a multi-site research trial where they looked at the impact variety selection could have on the Nitrogen Management of Malt Barley.
The concept of which was to see if some newer malt barley varieties which are higher yielding require more nitrogen, then an old variety such as AC Metcalf.
The trial was done in 2020 and 2021through Agri-ARM sites in Melfort, Prince Albert, Swift Current and Yorkton.
In 2021, when we had the widespread drought, they really didn't have any response from the added nitrogen on any of the varieties.
He says 2021 was kind of a bust it was an unresponsive, year to yields were unresponsive to add nitrogen and proteins were really high. So really gave us no information whatsoever to suggest some varieties should be fertilized differently.
"It was just too dry and yields are very low and because of the drought, our proteins were just through the roof. The malsters, they really are looking for proteins between 10 and 13 per cent and 13 is pretty high for some of them. When we put no nitrogen down whatsoever, just the soil background soil nitrogen at 70 pounds per acre, it was throwing proteins through the roof between 13 and 15% here. The part that's interesting here is even though we really didn't see any yield differences between any of the varieties. AC Metcalf which is normally a low yielding variety still has really high protein compared to AAC Synergy, which is normally a high yielding variety. So we got these protein differences even though we didn't necessarily see the yield differences in that year."
In 2020 they saw a good response with AC Metcalf (which is normally lower yielding) reaching its maximum yield sooner than other varieties such as AAC Synergy, which is what he was hoping to see, and it's more responsive, increasing its protein more rapidly than the other varieties as well.
He noted with a background nitrogen level of 40 pounds on average they saw a good response, with A-C Metcalf reaching its maximum yield and protein level sooner than other varieties, but with less nitrogen relative to the other higher yielding malt varieties.
"Let's just take 12.5 per cent as the maximum protein we want to aim for, for the malster. So we reached that with Metcalf at 115 pounds of soil plus applied nitrogen. In contrast, with Synergy we don't reach that at 12.5% protein until we've put down 150 pounds of nitrogen per acre of soil plus fertilizer. And so the background nitrogen is 40 pounds on average. So basically, what I'm saying here is we're applying 75 pounds to Metcalf and that's when we max out the protein, and then it takes 110 pounds to Synergy to max out the protein."
He adds that the nitrogen rate has to be based on your risk of tolerance to high protein levels, because obviously when you have too high a protein level that results in a rejection for malt.
"So because of that, I'm not going to suggest you should be fertilizing your malt with more nitrogen."
You can check out the East Central Research Foundations video "Do Newer Malt Barley Varieties Require More Nitrogen" here.