Grow more with less — that’s the goal of three Alberta researchers whose work could revolutionize the way we grow cereals.
“Canadian agriculture will be facing quite high demand for food production because of the growing global population and reduction in arable land,” said federal research biologist Alicja Ziemienowicz.
“We’re trying to give you the tools that will help you address the need for higher productivity.”
Farmers often hear the global population will approach 10 billion by 2050. An equally alarming — but rarely mentioned — stat is that per-acre productivity will have to soar in order to feed all those people.
“A 50 per cent increase in production over the next 20 years is what’s being asked of us,” said federal research scientist John Laurie.
That means ag researchers need to come up with solutions that will help farmers do that.
“I think of farming as a gamble. Anybody who has a farm is taking tons of gambles all the time,” added Haley Catton. “So my job as a scientist is to give you the information needed to improve the odds. Better research means better odds, which means a better bet for you.
“We want to make things better. That’s what gets me up in the morning.”
The trio of scientists from Ag Canada’s Lethbridge research station spoke at the Farm Forum Event in December and provided more details on their work in subsequent interviews.
‘Free pest control’
One of the ways Catton is ‘improving the odds’ is through her research into beneficial insects.
“Insects insist on being a big part of agriculture — we’re providing them with lots of food and habitat,” she said. “So we’re looking at the next steps for tapping the potential of beneficial insects.”
Beneficials, a catch-all term for any organism that reduces pest problems, typically do that in one of two ways — eating pests or by injecting eggs into pests (with the subsequent larvae then eating the host from the inside out).
“We want to encourage and preserve these beneficials because they’re providing you free labour and free pest control,” said Catton.
But right now, there isn’t enough awareness about beneficials — both among farmers and ag researchers.
“We need to know more about these things, but what we do know is that insecticides that we’re spraying for pests are also harming our beneficials, and that is a hidden cost,” said Catton.
“If you’re not sure if you’ve reached the economic threshold for a pest and decide to spray just in case, you may be incurring some hidden costs by losing the services of these beneficials.”
For example, it’s tough to pinpoint when or where these good bugs are active, or their impact.
“They have value — but how much? That’s what we need to work on,” she said. “We know they’re out there. We just don’t know how many dollars they’re worth at this point.”
Researchers like Catton are now conducting and compiling that research.
“Our desired outcome here is more pest control, less pesticide,” she said. “We want to reduce the guesswork as much as possible so farmers can make more informed choices about the costs and benefits of insecticide applications in their fields.”
But it’s complex research, and few studies have been done on the Prairies.
One from the 1990s valued the work of the wheat midge parasitoid wasp (Macroglenes penetrans) in Saskatchewan at over $248 million at that time. A more recent study from southeast England found predators and parasitoids of English grain aphid to be worth nearly $4 million a year in that region.
“These estimates are helpful, but they are regional. Ideally we would like to be able to provide field-level numbers, like dollars per acre.”
Catton is currently finishing a project in which cereal leaf beetles and beneficial insects were caged in small plots of wheat. Comparing the yield differences in each plot will provide some numbers on the yield loss the beneficial insects prevented.
“That would provide a concrete dollar value for the ‘free labour’ by the beneficials,” said Catton.
“The more we know about beneficials and their value, the more informed choice producers can make, saving unnecessary insecticide applications and reaping the benefits of nature’s free pest control.”
Finding those dollar values will be a complicated, lengthy process, but a necessary one, she said.
“It’s where we need to go to give producers the tools they need to maximize the benefits of the unpaid army in their fields.”
RNAi seed treatment
Like Catton, Laurie is looking for novel ways to protect cereals — he’s just thinking a little smaller.
At his lab, Laurie is working on a seed treatment using RNAi technology to prevent the formation of smuts and bunts in cereals.
“We’re working to include this technology in seed coatings as an alternative to toxic fungicides that we apply to seeds,” said Laurie. “It’s probably not a good thing to always use toxic fungicides on our seeds.”
RNA is the intermediary between DNA, the genetic blueprint, and the creation of proteins made from that blueprint. There are some DNA sequences — called transposons — that can change their position within a genome, which can cause gene mutations.
“This is something that occurs naturally in all of us, including plants, over long periods of time — many, many generations,” said Laurie. “But it’s not good to have these things jumping in and knocking out genes on a regular basis. So genomes protect themselves through RNAi.”
RNA interference — or RNAi — adjusts or even inhibits gene activity by binding interfering RNA to messenger RNA molecules, and then either increasing or decreasing their activity.
“If there is RNA that the cell doesn’t want — like a lot of transposon RNA or an invading virus that is making RNA — it gets rid of that,” said Laurie. “It’s a powerful tool for the cell to protect against transposons and viruses, but it’s also a great tool for us to then prevent certain pathways or prevent certain organisms from doing what we don’t want them to do.
“We can give them a certain phenotype or eliminate them entirely by targeting essential pathways.”
It’s complex science, but Laurie has already managed to block the growth of smut fungi, by using RNAi to target genes that make something called “infection hyphae.” Now he’s working on seed treatments that use this technology to stop infections before they start.
“There’s a very short window, a couple of days after seed germination, where it can actually infect the seed and cause disease on barley,” he said. “So by preventing the growth of this structure, we can prevent the disease and the later symptoms that you see.”
In other words, the seed treatment could eliminate the need for spraying fungicide later.
It’s too early to say what such a seed treatment might cost, but what is known is that the cost of producing large amounts of RNA has fallen a lot, and new products using this RNAi technology have been hitting the market.
“Right now, most of them are aimed at sprays for insects and viruses, but once we show the use for seeds, I think that technology can transfer over,” said Laurie. “A lot of the pieces are in place already, so it will probably only be a short period of time before it’s applied to seeds.
“There’s a lot of hope for this technology. I think it’s something farmers can be excited about, and they shouldn’t have to wait too long for it.”
What if cereals could fix nitrogen just like pulses do?
For starters, not having to buy nitrogen would cut the cost of growing cereals by about 20 per cent, dramatically improving profitability.
“Based on current prices of nitrogen fertilizers in Canada, we predict that nitrogen-fixing wheat will allow farmers to save about $45 to $70 per hectare, or even more if we include the costs of fertilizer application,” said Ziemienowicz.
Aside from being costly, the whole process of applying nitrogen fertilizer is wasteful, with a sizable portion either escaping as greenhouse gases or leaching into water.
“The reduction in the use of chemical fertilizers would benefit farmers and contribute to sustainable agriculture.”
Her solution? Biological nitrogen fixation.
There’s lots of nitrogen in the air (that’s where the N for synthetic nitrogen fertilizer comes from), but the problem is that plants can’t grab it.
“Biological nitrogen fixation is basically conversion of the atmospheric nitrogen — the richest source of nitrogen — into ammonia with help from specific organisms,” she said.
Pulse crops are able to do that because of bacteria — called rhizobia — that produce enzymes called nitrogenase. These rhizobia form symbiotic relationships with pulse plants, but cereals aren’t able to interact with these bacteria.
So Ziemienowicz wants to create a cereal plant that can fix its own nitrogen without help from rhizobia.
“We want to borrow the nitrogenase enzyme from this bacteria that knows how to do it.”
By transporting this enzyme to the plant cell’s mitochondria — “the power plant of the cell” — Ziemienowicz has shown biological nitrogen fixation can occur in the cells of a triticale plant.
“As far as I know, these are the first plant cells in the world that can fix nitrogen,” she said.
But right now, “these are just cells,” she added.
The next step is to use these cells to develop whole plants, using technology that allows researchers to produce an entire plant from a single cell (called double haploid production).
“Our ultimate goal is to transfer this trait to wheat by crossing wheat with the triticale that has the biological nitrogen fixation trait,” said Ziemienowicz.
“We hope to get wheat with biological nitrogen fixation, and this will give us an alternative to the use of fertilizers, which cost quite a lot of money.”
But that’s a ways down the road.
If everything goes as planned, researchers should be able to create a nitrogen-fixing cereal plant within the next few years — but getting that cultivar to market will take at least another decade.
“Commercialization for a new crop variety or cultivar is a long process, and in the case of nitrogen-fixing cereal plants, it will take even longer,” said Ziemienowicz. “Because our plants will carry foreign genes, the assessment of such plants with this novel trait will be very detailed.
“Most likely, it will take about 10 years before the first variety will be available commercially. But the outcome will positively change Canadian and global agriculture.”