Like prospectors searching for the mother lode, canola breeders are on a never-ending quest for the next highest-yielding hybrid.
Whether it’s a rich gold vein or higher yields, the more one looks, the better one’s chances of finding them.
Biotechnology is helping companies such as Dow AgroSciences screen more crosses faster, Van Ripley, Dow AgroSciences’ global breeding leader for canola, tells reporters during a tour of the firm’s plots in July.
“We have basically quadrupled – or more than that – our throughput and we haven’t hired additional people in our lab…,” he says during a tour of Dow AgroSciences’ research facilities.
It’s the result of a combination of things – double haploid techniques, which speeds up plant breeding, molecular markers that tell researchers whether the genes necessary for oil quality, disease resistance or herbicide tolerance are present before field testing, robotic screening, which speeds up oil and meal assessments and bioinformatics, which catalogues all the data.
“It’s all about running numbers through your pipeline. So what the technology does is it just enhances that by using screening technologies… to drive more numbers in the early stages at a lower cost than putting lines in the field,” says Jim Wispinski, Dow AgroSciences Canada’s president and CEO.
Dow AgroSciences develops hundreds of thousands of new canola plants a year. Around 20,000 are planted in its field nurseries annually and assessed for their agronomic potential such as yield, early-season vigour, days to maturity and stand-ability. Because the lines have been screened before they get to the field, Ripley already knows they have the oil profile or herbicide tolerance he wants.
“We’re spending the whole summer taking notes,” he says.
“By the end of the year you have an almost pre-select list of the ones that look the most promising.”
Only 50 to 75 end up in the first year of co-op trials– the final stage towards commercialization, Ripley says. Although it varies from year to year, only a couple will make it to farmers’ fields.
It takes seven to eight years to commercialize a new variety of Dow AgroSciences’ Nexera canola, which produces a high-stability oil used for frying food in restaurants and food manufacturing. The oil has all the health benefits of regular canola oil, with the functionality of hydrogenated canola oil, but without the accompanying unhealthy trans fats.
Dow AgroSciences, which operates in 40 countries with 1,800 employees, has increased its research budget, including for canola, but company officials, citing competitive reasons, won’t say by how much or what it spends in total.
However, $340 million has been spent improving its research and office facility here – Dow AgroSciences’ world headquarters for spring canola, says Sara Freeman, Dow AgroSciences’ field program and registration manager.
Traditional plant breeding involves taking two parent plants, crossing them and hoping the offspring performs better than the parents, Ripley says. Traditionally, the way to lock in genetic stability when developing a hybrid is to self-pollinate the line for five or six generations. Even then there can be some variation and the process takes several years. But double haploid production accomplishes the same result in one generation and takes less than a year.
SPEEDS UP SCREENING
In traditional plant breeding, pollen is placed on the stigma and fertilizes the egg producing a fertile plant. In the double haploid process, immature pollen grains or microspores are selected. These microspores contain a single set of chromosomes. The microspores are cultured in a media that doubles the chromosome – a prerequisite to becoming normal plants.
The microspores are placed in darkness for three days at a high temperature to induce embryos. Then they are incubated at 25 C for 18 days and then placed under light to develop chlorophyll. Next there’s four weeks of cold treatment to encourage embryo regeneration so they start to form normal plantlets. The plantlets are plated on agar medium to promote root and shoot development.
Tiny leaf samples are collected and put through a flow cytometer, which determines whether the plantlets have a full set of chromosomes. Sixty to 70 per cent do, Freeman says, and those are transplanted and placed in growth chambers and eventually greenhouses.
“I can use molecular markers to screen little plantlets as they’re coming out of the lab to only pick the ones that have our genes,” Ripley says. “So rather than taking 500 out to the field and only one-quarter of them have our profile I can screen 1,000 as they’re coming out of the lab and only take the ones that have our genes.”
The double haploid process and molecular markers fall under “biotechnology,” even though neither alone results in the production of a genetically modified (GM) plant. Biotech, which Oxford Canada defines as “the exploitation of biological processes for industrial and other purposes… “ goes beyond inserting genes into plants using guns or bacteria instead of traditional sexual reproduction.
Seeds produced by those double haploid plants are run through a near-infrared spectroscopy (NIR) machine, which measures the protein in the seed’s oil and fatty acid profile without damaging the seed.
Dow AgroSciences has automated the process allowing it to screen 10,000 seeds a week.
Ripley says in the past he had to plant those seeds, do a bulk NIR test with up to 1,500 seeds at a time, which took four months.
“If I screen 10,000 seeds (now) I can pick 1,000 that have my profile rather than picking out 10,000 up to the point of producing seed and then measuring it,” Ripley says. “So it’s pretty powerful.”
It also creates a lot of data. That’s where “bioinformatics” comes in.
“If you’re screening through 250,000 plants per year you’ve got to be able to keep track of which plant is which,” he says.
“We use things like bar-coding on all of our stuff.
“When I did my PhD coming up on 20 years ago, none of this was existing. So it’s pretty phenomenal.”
It’s no wonder Ripley is optimistic about the potential for much higher canola yields.
“My personal feeling as a canola breeder is no, we’re nowhere near maxing out canola’s potential,” he says.
Hybridization is still relatively new to canola compared to corn.
“They have been working on it (corn) for 80 years and look at the gains they’ve made and it’s continuing. So I think we’re at the very beginning with canola.”