Agriculture researchers Kirstin Bett and Sabine Banniza.
Agriculture researchers Kirstin Bett and Sabine Banniza.

The pulse of the Prairies

Kirstin Bett wants to nearly double the acreage devoted to pulse crops on the Prairies—about one-fifth of the West’s 70-million crop acres.

"Our goal is to have pulses in a one-in-four-year rotation—let's say 20 per cent of the landscape," said Bett, a professor in the Department of Plant Sciences in the College of Agriculture and Bioresources. "We're at 12 per cent, so we're not there yet. But we want to offer every producer at least two species of pulses so they can include these legumes in their rotation."

Pulses (dry peas, lentils, dry beans, chickpeas and faba beans) pack a triple punch: they provide affordable protein for a growing world population, they are a rich source of fibre and nutrients with multiple health benefits, and they naturally add nitrogen to the soil.

It is a win-win-win with just a teensy problem—plant breeders need to develop varieties that are better yielding, can thrive in areas where pulses are not traditionally grown and are resistant to a host of diseases.

It is a tall order, but Bett and her colleagues at the U of S Crop Development Centre (CDC) have a record of filling such orders. In the 1970s, virtually no pulses were grown in Saskatchewan. Since U of S plant breeder Al Slinkard released the Laird lentil in 1978, the CDC has produced more than 200 pulse varieties.

As of the 2015 crop year, about 3.9 million acres of lentils and 3.7 million acres of dry peas were grown. But to expand this, Bett and colleagues Bert Vandenberg, Tom Warkentin, Bunyamin Tar'an and plant pathologist Sabine Banniza face a see-saw battle.

For example, one of the centre's earliest successes was chickpeas, which went from 10,000 acres in 1996 to more than a million in 2001. By last year, it was a tenth of that amount.

"Declining prices were a factor, but disease played a major role," said Banniza. "We had major infestations of ascochyta blight."

It comes with the territory: plant millions of acres of any crop and disease pressure skyrockets, especially if you plant the same crop on the same field every two or three years. Today, one of the biggest threats to peas and lentils is a root rot, first discovered in Saskatchewan in 2012 and now widespread.

"If you go into areas where they have a lot of problems, you can see a very clear trend between how often they grow a pea crop and the incidence of root rot," Banniza said.

Growers demand improved disease resistance, varieties better suited to the northern plains and a host of other traits such as larger chickpeas, which fetch higher prices on world markets.

The challenge is exacerbated by pulse crops' origins in tropical or subtropical regions—a vastly different place than the Canadian Prairies.

"First of all, you can't plant them before the ground is warm enough, so you have to wait until the last week of May, then you need them to come out of the ground quickly," Bett said of dry beans. "Because traditional varieties are often sensitive to day length, they typically don't flower until there are 12-hour days—and guess what?—we don't get those until the day before harvest. They're also super-sensitive to frost. So yeah, they're a lot of fun."

Lentils have the opposite problem—the long days of June make them want to flower soon after emerging from the soil.

Researchers are looking to genetics to help them crack these tough problems. Bett is project lead of the international lentil gene sequencing effort. Earlier this year, she and her colleagues published an important genome milestone.

"The lentil genome assembly will help us better understand this crop," she said. "More importantly, it will lead to development of genomic tools that will help improve breeding practices and accelerate varietal development." These tools will allow breeders to track multiple, complex traits during cross- breeding, which will help them develop high-quality and high-yielding lentils in less time.

Banniza cites the tightly integrated nature of the CDC team as another competitive advantage.

"We sort of pollinate each other with new ideas," she said, pointing to genomics as example. "I'm surrounded by plant breeders and one of the things all plant breeders do these days is map genomes. So one day, I thought, ‘Why don't I try this with a fungus?'"

It was an inspired idea.

"If you understand what makes a fungus virulent, what genes are involved, and how quickly they change, then you have a better understanding of how good your resistance is and how long it might last," said Banniza.

Another example of their team approach is KnowPulse, which Bett described as "a breeder-friendly web portal you can use without knowing anything about databases."

Just as you might want to find a store in your neighbourhood, a plant breeder might be interested in a gene that inhibits a particular enzyme. Type that into KnowPulse and you can find all the genes in the database that are similar, and in some cases, where they are located on a chromosome of a similar plant.

Bett cites an old saying that plant breeding is like a lottery, and 99 per cent of all crosses "will break your heart."

"It's not cheap to develop a variety," she said. "It takes a good 10 years from the time I make a cross to getting it out on the landscape. So the more you can increase efficiency—either in costs or time—the better."

 

Glenn Cheater is the owner of High Bluff Media in Winnipeg and Edmonton.
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