WESTERN PRODUCER — A canola innovation that could result in dramatic yield gain is getting closer to reality.
Next spring, University of Guelph scientists plan to conduct field trials in Manitoba, Saskatchewan and possibly Montana on lines of transgenic canola that have produced 50 percent more pods and 50 percent higher seed yield in a greenhouse.
“In the control canola lines … we’re getting about 200 siliques (pods) per plant,” said Michael Emes, a professor of molecular and cellular biology at the U of G.
“In the transgenic lines, we’re getting about up to 300.”
Emes cautioned that greenhouse results are not the same as the field, where heat, cold, disease, soil moisture and many other factors can hinder a crop’s performance.
But that’s why the scientists are pursuing field trials. They want to know if their unique lines of canola can handle real world conditions.
“In a controlled environment, in a greenhouse, (there was) an average of about 50 percent more in terms of seed weight,” Emes said.
“It will be really interesting to see whether what we see in controlled conditions (can be repeated in the field).”
If they get a 25 percent yield boost in the trials, that would be a victory, Emes added.
Next year’s field trials will happen more than eight years after Emes and a U of G colleague, Ian Tetlow, made a surprising discovery.
They were studying starch biosynthesis and wanted to know if a starch-branching enzyme in corn could help a model plant, arabidopsis, form starch in its leaves.
Starch biosynthesis is the process where a plant converts sunlight into starch.
When the scientists transferred the corn enzyme into arabidopsis, it did increase and change starch production in the leaves.
But something else happened.
“When we looked at the plants … they were huge. They were about twice the size of the normal arabidopsis plant,” Tetlow said in 2016.
The genetically altered plants produced far more flowers and an incredible number of seeds. The seed yield in arabidopsis is typically 11,000 seeds per plant, but the transformed plants with the corn enzyme produced more than 50,000 seeds, nearly five times the yield.
The result was a shocker, so the scientists repeated the experiment, again and again.
Every time, the growth rate and seed yield of the arabidopsis plant went through the roof.
The researchers knew that a unique discovery had fallen into their laps.
“This was a pure fluke. We weren’t doing these (starch) experiments thinking about canola yield. We were studying starch metabolism,” Emes said in mid-October from his university office.
In March 2016, Emes, Tetlow and another scientist, Fushan Liu, published a paper on their findings. Thus began the hard work of replicating the discovery in a commercial crop such as canola.
With funding from SaskCanola, Alberta Canola Growers, Manitoba Canola Growers and the Canadian Agricultural Partnership program, the researchers started down the road of integrating corn genes into canola.
Emes and Tetlow studied and worked in the United Kingdom before moving to Canada. They know a great deal about the biology of plants and specialize in their metabolism, but they’re not experts in a relatively new technology called gene editing.
Using gene editing tools such as CRISPR Cas 9, scientists can delete specific genes from a crop like canola or wheat.
Liping Wang, a research associate in molecular and cellular biology at the U of G, took on the challenge of removing genes that help make and manage starch in canola.
“It turned out there were six genes we had to knock out in canola,” Emes said.
“Liping was the one who introduced the gene editing technique to do that.”
Once that was accomplished, Wang noticed the canola plants with the edited genes were different.
Mostly, the stem of the plant was thicker than normal.
“(It was) 17 millimetres for the diameter of the main stem,” she said, compared to the usual 13 mm.
Then, Wang used transgenic technology to move genes from corn into canola to replace the deleted genes. The corn genes express starch branching enzymes, which are one of the major groups of enzymes that help make starch in plants.
“When we eat a seed, like maize or wheat or rice, mostly what we’re eating is starch,” Emes said.
In this case, the corn enzymes are changing how the canola makes and manages starch in the plant tissue.
“You could say that the starch in the leaf is helping the fitness and vigour of the plant. And we’re improving the vigour of the plant by modifying that starch … using a different source of enzymes,” Tetlow said.
“There’s lots of literature … showing that improving starch synthesis in leaves actually helps the plant produce more flowers and tubers and seeds.”
Wang has designed 11 lines of canola, which will be tested at sites in Western Canada and the northern U.S. Plains.
If the growing conditions are hot and dry, it will be interesting to see how the canola performs.
The wider canola stem persisted, even after Wang moved the corn genes into the canola plants. Greenhouse experiments at Guelph suggest the wider stem can transport more water to the leaves and flowers.
“The priority is to look at the silique (pod) numbers and the total seed weight,” Wang said, explaining what they will be measuring in the trials.
“Also, we have a very thick main stem. So, we also want to look at lodging resistance and drought tolerance.”
The U of G scientists are planning three years of field trials.
If the canola lines perform as expected in the trials, the next step would be putting the corn enzymes into elite canola lines.
There’s also the matter of regulatory approval for the transgenic canola, which would likely take several years.
Given the hurdles, a canola variety with starch-branching enzymes from corn is probably 10 to 12 years from commercialization.
The researchers do have a patent on the process, but Tetlow and Emes are more excited about the potential impact on the canola industry.
“As scientists, it’s really nice to see that. Going from the basic science, through the process of serendipity…. (Then) to have something of value for growers, for Canada and for a crop that’s pre-eminent in Canada.”
If the field trials are successful and there’s a realistic path to commercialization, the impact of their discovery could be much larger than canola.
Of all the research he’s done during his career, this project “is probably the biggest,” Tetlow said.
“This is a technology that could, quite likely, be extended to other crops.”
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