Author: cwrc2023dev

Written by: Ellen Cottee

Lead Researchers: Dr. Sylvie Cloutier (AAFC – Ottawa) and Dr. Curt McCartney (AAFC – Morden)

With a global population of nine billion expected by 2050, many in the agriculture industry are interested in finding tactics to keep up with the growing demand for food. For Canada, feeding the world means growing and exporting even more wheat, a crucial crop due to its nutrient and calorie density.

One response to the call for improved and increased wheat production includes pre-breeding – a process that identifies key characteristics and genes in plant materials other than domestic wheat, and transfers them to materials breeders can work with to develop new varieties.

 Wheat geneticists are the first step in this process, narrowing down genetic data to find DNA markers and germplasms that show promising disease resistance and crop resiliency. Despite doing critical research, however, their findings don’t always see the light of day.

 “I found the work [geneticists] were doing fascinating,” said Dr. Sylvie Cloutier, principal research scientist with Agriculture and Agri-Food Canada – Ottawa, “but often, they were working in isolation or with one breeder, and their discoveries were not being taken up.”

 Building upon past research and discussions, Cloutier and her team received funding under the 2018-2023 Canadian National Wheat Cluster to bridge this information gap, setting out to create a database where wheat geneticists can share all their findings.

 “We needed to have a platform that was national in scope, that was fully open, where material and data is publicly available to everybody,” Cloutier explained, “and the chance to have it taken up would be greater.”

The platform is home to DNA markers and germplasms containing desirable traits, with the majority of current data focused on resistance to fusarium head blight and common fungal diseases. Instead of raw data, the database will also have search functions for breeders to narrow down traits of interest as well as a curator to assist with the addition of more information in the future.

Creating new wheat varieties through pre-breeding happens in three steps: discovery, transfer and deployment. This project focused on the first phase, compiling the important information geneticists find in the germplasm and DNA of wheat relatives. Cloutier said she hopes to move their work forward to the transfer phase in the upcoming 2023 – 2028 research cluster.

Adjacent to the creation of this platform, Cloutier received funding from Genome Canada to research wild wheat genetics – another key component of the pre-breeding process. These ‘cousins’ of cultivated wheat have genetic properties desirable to wheat breeders, growers and exporters, presenting an opportunity to further the genetic diversity and resilience of cultivated wheat varieties.

Looking to the future, Cloutier plans to progress the platform to the transfer phase of varietal development through the upcoming 2023 research cluster. Above all, she hopes her work contributes to – and helps to grow – Canada’s stellar wheat reputation.

“My goal is to make sure Canada continues to produce the best wheat, and we never lose that edge,” she said. “Canadian agriculture feeds the world, and I want us to stay there.”

This multidisciplinary project is developing new winter wheat germplasm and varieties adapted to Eastern Canada, particularly western Ontario. Their objective is to incorporate enhanced disease resistance, tolerance against yield-limiting abiotic stresses (such as sub zero temperature during the winter and frost heaving caused by freeze and thaw cycles in the spring), higher yield, and improved quality.

The program includes two different breeding pipelines and employs genomic selection technology and DNA marker-assisted selection to accelerate advancement. Genomics is the study of plant genes (the genome). Genomic selection can be used to select for desirable traits, which can shave years off breeding trials by predicting how new lines will perform based on genetic markers.

The project was started by Alireza (Ali) Navabi, who led the University of Guelph wheat breeding program until he passed away in March 2019. While the scope has changed somewhat, this project continues. Helen Booker, who had been leading the flax genetics and breeding program in the Crop Development Center at the University of Saskatchewan, took over stewardship of the program in September 2020.

“We’re focussing on improving yield and yield stability, and that centres around improving disease resistance,” says Booker.

Fusarium head blight (FHB) is a major concern, not only because it causes yield reductions, but it can also contaminate the grain with deoxynivalenol (DON). Booker explains that DON can impact the functional characteristics of grain for end uses (such as making pastry or bread) and can be a human and animal health issue.

Booker says her program is looking at the inheritance of traits to help them breed more efficiently for those traits. They are screening early in development for lines that have alleles (different forms of the same gene) known for resistance to FHB and rusts.

“When we know which fixed lines carry those alleles, we can bring them forward even before it gets to the disease nursery stage,” she says. “Eventually we’ll test them in a nursery, but if we know that information beforehand it improves our selection efficiency for disease resistance.”

Stripe rust is a new disease in Ontario, and Booker says there isn’t much genetic resistance to stripe rust in current varieties, so they’re identifying rust resistance alleles and integrating those into their breeding program as well.

In addition to screening fixed lines, they’ve also started to do their own crosses. Some of their first crosses are now at the registration testing stage. “In a couple of years, we should have material out that comes from crosses initiated at the University of Guelph,” says Booker.

Booker’s team has been working with germplasm they received from Limagrain Cereals. She says the first product to come out of that germplasm source is OAC Constellation. It’s currently being registered for production in Ontario and will be available through SeCan.

It meets all of the agronomic requirements, says Booker, and it’s rated resistant to stripe rust and moderately resistant to FHB.

In 2021, two more lines of soft red winter wheat were supported for registration

• OAC  19SRW01 is moderately resistant to FHB and leaf rust.

• OAC  19SRW03 is moderately resistant to FHB and stripe rust.

This Wheat Cluster project received funding from Agriculture and Agri-Food Canada through the AgriScience Program, which is part of the Canadian Agricultural Partnership, a federal, provincial, territorial initiative. This project also received funding from Grain Farmers of Ontario, Producteurs de grains du Quebec, and SeCan.

To read the project profile, CLICK HERE.

Fusarium head blight (FHB) is a fungal disease that infects wheat and other cereal crops. Depending on when infection occurs, FHB can reduce the number of kernels developed or result in Fusarium damaged kernels (FDKs) and contamination with deoxynivalenol (DON). If infection happens later, kernels may not appear damaged, but could still contain DON, which is a health risk for humans and animals.

“The presence of FDKs in harvested grain results not only in a reduction of yield and downgrading, but the infection will also impact functional characteristics of the grain for end users,” explains Kelly Turkington, a research scientist with Agriculture and Agri-Food Canada.

FHB is a difficult problem to manage. “Breeders have made incremental improvements, but the varieties we have available still don’t provide a high level of resistance,” Turkington says. “Fungicides provide suppression at best, and the crop rotations we’re using are not quite long enough to be an effective disease management tool.”

He recommends an integrated approach. “You can’t rely exclusively on one tool, you need a set of tools,” he says. “You need to rotate (not plant wheat on wheat), you need to apply a fungicide at anthesis (flowering), and you need to grow a ‘resistant’ variety.”

Turkington is running two different trials to explore a number of cropping strategies to reduce the impact of FHB. One is looking at crop rotation and residue management.

“We’re hoping to demonstrate the role extending the rotational interval from one year to two, or even three years, can have on disease risk, meaning the amount of infected residue that persists until the next time you grow wheat in that field,” explains Turkington.

Infected residue allows the pathogen to overwinter on the field and can result in spore production and reinfection if a cereal is grown the following year. The idea is to remove some of that highly infectious crop residue to reduce the extent of FHB infection in subsequent years.

The other trial is looking at row spacing, seeding rate, and fungicide timing.

He’s comparing narrow row spacing (7 to 10 inches) and wider row spacing (12 to 14 inches). Traditional thinking, he explains, suggests wider row spacing will lead to more air movement and shorter periods of high relative humidity and leaf wetness, which should discourage FHB. However, wider row spacing may also provide more wind access to infected stubble, which means spores could be more readily carried up onto the head. His theory is that low row spacing likely won’t have an impact on micro-environments, but it might help reduce spore dispersal.

He’s also comparing low and high seeding rates. Lower seeding rates result in more secondary tiller development and a less uniform crop. If you spray a fungicide when the main-stem tillers begin to flower, which is the ideal time, the heads on secondary tillers may not even be out and won’t be protected. Turkington’s theory is that higher seeding rates will result in more uniform crop development, more uniform head emergence, and hopefully better management of FHB when fungicides are applied.

Finally, he’s looking at four different fungicide treatments:

• No spray (as a check)

• Early application (about 4 days after head emergence)

• Later application (about 7 to 10 days later)

• Dual application (early and again later)

Traditionally, fungicide application happens at the beginning of anthesis. “It’s a key time for infection and production of FDKs and DON,” Turkington says. “If you apply a fungicide later, the concern is that it might not have the same impact. Based on research out of the US over the last five or so years, that simply isn’t the case.”

He says you can apply a fungicide later and have very similar, if not better management of FDKs and DON. However, later application may have implications for recommended pre-harvest intervals. Later or dual applications would likely require revisions to fungicide labels.

This Wheat Cluster project received funding from Agriculture and Agri-Food Canada through the AgriScience Program, which is part of the Canadian Agricultural Partnership, a federal, provincial, territorial initiative. This project also received funding from Alberta Wheat Commission, Saskatchewan Wheat Development Commission, Manitoba Crop Alliance, and Western Grains Research Foundation. Turkington is hopeful his research will lead to improved strategies to mitigate FHB in wheat, thus limiting the impact of this issue for producers.

To read the project profile, CLICK HERE.

Spring wheat accounts for about 90% of the wheat grown in Quebec—half is milling wheat, the other half is feed wheat. Unlike other regions of Canada, the feed wheat market is very important in Quebec, explains Silvia Barcellos Rosa, wheat breeder, Centre de recherche sur les grains (CÉROM).

She says growing conditions in Quebec are not as well suited to producing quality wheat as those in the Prairies. Canada eastern red spring wheat often has lower protein content and gluten strength than Canadian western red spring wheat grown in the Prairies. While it’s reasonable to assume this quality difference is mainly due to environment, wheat breeders developing new varieties for Eastern Canada are selecting for traits that will improve bread-making qualities.

The price of feed wheat in Quebec is similar to the price of milling wheat, but producers grow feed wheat because they can get a higher yield. “Local millers want to use more wheat from Quebec,” Rosa says, “but there’s not enough good-quality wheat grown here. If we can improve the quality, farmers will benefit from higher prices and better local markets.”

Eastern farms are also more likely to be affected by Fusarium head blight (FHB), a fungal disease that can significantly reduce yield and produce mycotoxins. Rosa acknowledges that FHB resistance is important everywhere, but she says “it’s especially so in Quebec because of climate conditions. A variety with good resistance to FHB would have a huge impact for Eastern producers.”

Rosa is using new breeding technologies to develop varieties with higher yield, improved quality, and more disease resistance, especially to FHB. For example, her program has built an indoor quality lab. “We can now select for quality indoors, which is something we were missing in the past,” she says.

She is also using speed breeding to develop advanced lines and get them to market as quickly as possible. When you’re growing outdoors in Canada, you can only grow one generation per year in the field. Rosa is using indoor growth chambers with 22 hours of light to grow four generations per year.

“The idea is to advance the lines indoors until they’re genetically stable, then select in the field,” she explains. “We’re not jumping the selection stage, but we’re selecting later.”

She’s also employing marker-assisted selection to identify desirable traits. She screens for genetic markers on DNA samples in early generations to identify plants that have the traits she’s looking for. This lets her direct her efforts to plants/lines with higher potential, which reduces the cost of field experiments later in the breeding process.

She’s also trying to identify genes that will help new varieties be more resilient to climate extremes. “The idea is to identify genetic regions that are related to broad adaptability,” she explains.

Climate change is a big concern. “We need to focus on material that can better tolerate abiotic stresses like high temperatures and dry conditions,” she says. “We’re going to evaluate cultures from all over the Americas and have trials in Brazil, Paraguay, Uruguay, and Quebec to try to identify lines that have broad adaptability and good resilience. We can then use those materials in crosses to develop new cultures that can better adapt to climate change.”

This Wheat Cluster project received funding from Agriculture and Agri-Food Canada through the AgriScience Program, which is part of the Canadian Agricultural Partnership, a federal, provincial, territorial initiative. This project also received funding from Producteurs de grains du Québec and SeCan. Rosa is using the funding to develop spring wheat varieties for Eastern Canada that will have higher yield and better quality for the milling industry, be resistant to major diseases, contribute to environmental sustainability, and, ultimately, increase profitability for producers.

To read the project profile, CLICK HERE.