The committee charged with approving new wheat varieties for Prairie farmers is grappling once again with the age-old tension between agronomics and end-use qualities.
This time the Prairie Recommending Committee for Wheat, Rye and Triticale (PRCWRT) annual meeting here last week was confronted with a new hard red spring wheat with improved tolerance to fusarium head blight, and which produces less deoxynivalenol (DON) when infected.
But its gluten strength, which is important to customers, is borderline, and that could block its commercialization.
BW980 was developed by Agriculture and Agri-Food Canada wheat breeder Richard Cuthbert at Swift Current, Sask. Originally it was among the 26 wheats the PRCWRT — a committee of experts and grain sector participants — was to assess and then decide whether to recommend for registration by the Canadian Food Inspection Agency.
Instead, Cuthbert opted to table the variety, aimed at the Canadian Western Red Spring (class), for a year so more bread-making data can be collected.
After two years of trials BW980’s dough strength was close to Carberry’s, which is the new check variety for the low end of what’s permitted in the recently revised CWRS class. However, Graham Worden, chair of the PRCWRT’s quality elevation team reported in 2015 BW980’s gluten strength was well below that of Carberry.
BW980 was rated by the disease evaluation team as ‘moderately resistant’ (MR) to ‘resistant’ to fusarium head blight (FHB).
“It has said that if it was tested against AAC Tenacious VB (in the Canada Prairie Spring class), which is the only spring wheat currently given an R rating to FHB, then that comparison could be made and that rating could be revised,” Cuthbert said in an interview. “But it (BW980) does appear to have a very strong MR and is better than Carberry based on three years of testing at multiple FHB nurseries.”
Fusarium head blight can significantly reduce wheat yields and quality. The disease can produce DON, a toxin that in high enough concentrations can prevent wheat from being consumed by humans or even livestock.
When infected with fusarium head blight, BW980 produces less DON than other CWRS wheats.
“We don’t see that very often in our breeding material,” Cuthbert said. “We don’t have a good handle on genetic controls, so breeding for it is difficult.
“But we do know there is genetic control of DON accumulation in grain and that’s an area we are focusing on and breeding for sure.”
Cuthbert is already using BW980 to develop other wheat lines, so even if it doesn’t get registered a lot has been gained.
Strong agronomic package
BW980 has a strong agronomic package, including a four per cent yield advantage over Carberry, making it competitive with some of the new, higher-yielding CWRS wheats already on the market.
“It’s about five centimetres taller, but well within the range of Glenn and Carberry in height, which I think producers are looking for and the rest of the disease package has been excellent,” Cuthbert said.
As one PRCWRT committee member observed, BW980 pits a clear agronomic advantage against what could be poor end-use quality.
“Both issues are relevant,” said David Hatcher, a PRCWRT member and the Canadian Grain Commission’s program manager for Asian products and wheat enzymes.
But he also noted Canada has tightened the quality standards for CWRS wheats because of complaints from domestic and foreign customers that gluten strength is not as consistent as it used to be. The grain commission blames that on the dominance of three low-gluten-strength varieties — Harvest, Unity and Lillian — in the CWRS class. The three will be moved to the new Canada Northern Harvest Red class Aug. 1, 2018.
Given BW980’s improved tolerance to head blight, reduced DON levels and other attributes, it probably would be widely grown by western Canadian farmers, Hatcher said. And if its gluten strength is substandard it could undermine the whole CWRS class, he said.
“I don’t have a definitive answer for you, but this is the dilemma we face,” Hatcher said.
Cuthbert stressed he doesn’t want to jeopardize Canadian wheat markets.
“We definitely want to work within the procedures… of the revised CWRS,” he said. “We don’t want to cause harm to the class. We respect the branding of CWRS and what it means to customers. We want to confirm whether the one (year) out of three is an anomaly or if it is in fact true that it is weaker extensibility than Carberry.”
If BW980’s gluten strength doesn’t meet the CWRS standard, it probably would fit in the new Canada Northern Harvest Red (CNHR) class, which allows for lower gluten strength. However, Cuthbert said it’s unlikely he’d try to register BW980 for the CNHR class because it yields lower than other wheats in the class.
There were 27 candidate cultivars before the PRCWRT this year — 26 wheats and one fall rye.
Of the 26 wheats before the PRCWRT, all but four were approved by the PRCWRT’s three evaluation teams — agronomy, disease and quality — and therefore did not have to be voted on by the PRCWRT’s voting panel of up to 23 members.
The four voted on were BW488 and BW986 destined for the CWRS class and Alderon VB and Charing 2014-2 VB, destined for the Canada Special Purpose class. The voting panel voted in favour of recommending BW488 and BW986 for full registration and Alderon VB and Charing 2014-2 VB for three-year interim registrations.
The discussion and voting took just over an hour.
Three high-yielding American Dark Northern Spring wheats — Faller, Prosper and Elgin ND — which had interim registrations, were recommended for full registration in the new Canada Northern Harvest Red class (see page 22).
Two cultivars were tabled — BW980 and Sparrow.
The wheats by class are as follows: CWRS: eight, Canada Prairie Spring red: three, Canada Northern Harvest Red: three, Canada Western Amber durum: three, Canada Western Red Winter: two and Canada Western Special Purpose: seven.