Brown rust takes performance toll

Brown rust looks to have had the biggest impact on varietal performance in HGCA Recommended List trials so far, according to Peter Hanson, a HGCA RL consultant.

“The varieties performing better are those with more resistance to brown rust,” he says.

Saffron, Flagon and Pearl, for example, are yielding higher relative to the controls this year than their five-year rolling mean, he says, while Carat, Spectrum and Retriever are lower. “I suspect that’s down to brown rust.”

Yields in the seven trials – all bar one from East Anglia – have held up well. At 8.22t/ha they are only a fraction down on the 8.48t/ha rolling average. “It is a bit of a surprise,” Mr Hanson admits.

Yield differences between the four malting varieties – Pearl, Flagon, Cassata and Wintmalt – are within 2% of each other so far this year. “The only real difference is Pearl, up 2% on its average. On balance there is not much to choose between them.”

It could mean growers have four malting varieties to choose from, although Mr Hanson suggests the malting industry will be only comfortable with a maximum of three. “And they would probably prefer just two.”

Both Cassata and Wintmalt have mosaic virus resistance. “That could allow growers to expand the area they grow malt in, which will be attractive to the malt industry.”

In the feed sector Carat, Spectrum, Retriever and new candidate variety Actrice are all 2-3% down on their running means. “They’re all fours or fives for brown rust.”

Saffron is having a good year at 105% of the controls, he says. “And Retriever, even though it is down, is still the highest two-row feed variety [at 106%]. They are the two to consider.”

The six-rows are a “trifle weird”, so far, Mr Hanson suggests. “I can’t explain why Pict is having a good year, and Sequel not.” But most of the sites harvested so far are not really in the traditional six-row territory of the north, he points out. “I’d be surprised if there weren’t some changes when all the sites are in.”

Two hybrids – Bronx and Zzoom – from Syngenta Seeds are having good years at 112% and 114% respectively. Both have better brown rust resistance than Colossus and Boost. “The breeding effort to overcome the brown rust and mosaic virus resistance seems to be paying off.”