Decoding Lentils
Written by Dr. Catalina Lopez-Correa, Chief Scientific Officer at Genome Canada
Most of us understand the truth in the saying ‘You are what you eat.’ But the food you choose can also be healthy for the environment.
Take lentils for example. Lentils are an inexpensive source of plant-based protein, fibre and micronutrients such as folate and iron. Like other pulses, including chickpeas and beans, lentils naturally enrich soil with nitrogen, reducing the need for petroleum-based fertilizers. That’s a good thing because the manufacture of these fertilizers emits CO2 into the atmosphere.
Lentils perform this trick by forming a symbiotic relationship with bacteria that convert nitrogen in the atmosphere to a form the plant can use for growth. In exchange, the plant gives the bacteria a little sugar snack. This conversion of atmospheric nitrogen into a usable form may help to explain why when farmers plant cereal crops in plots that previously grew lentils, the cereal plants thrive.
Yet as our climate changes, important foods such as lentils need help adapting to higher temperatures. Enter Kirstin Bett, a University of Saskatchewan plant scientist and her team, who use genomics to predict which varieties will do well in what environments. Genomics is the science of deciphering and understanding the entire genetic information of an organism.
She and her team partnered with researchers around the world to plant 324 lentil varieties in nine lentil producing areas, including two in Saskatchewan and one in the United States, as well as sites in South Asia (Nepal, Bangladesh and India) and the Mediterranean (Morocco, Spain and Italy).
In each case, they were looking at a key predictor of crop yield: days to flowering. This is the number of days it takes to go from seed to flowering plant.
“What makes a lentil flower and how it matures at an appropriate time at a given location is controlled primarily by day length and temperature,” says Bett. “We don’t know yet the genes that make that happen.”
But by planting a given variety in various locations around the world, with various day lengths and temperatures, Bett and her team are figuring it out. For example, if the lentil responds to a short-day length with the appropriate number of days to flowering, they know it contains the genes to do well in that environment.
This is important information because it lets farmers choose lentils with genes best suited to conditions in new areas. In places like Southeast Asia, higher temperatures as a result of climate change may force farmers to move their crops to higher, cooler altitudes. Here in Canada, higher temperatures could mean moving crops further north, where daylight hours are even longer during the summer.
“We’re not competing. We’re collaborating.”
It’s one thing to know a lentil contains the gene you want. It’s another to know which gene in the genome is responsible for the trait. A genome is the complete set of genes and genetic material in each living thing.
Pinpointing the desired form of a gene is done through statistical analyses and a knowledge of what genes lie where on the genome. Once breeders determine the genes they want, they can develop molecular markers that will let them pre-screen seeds. A molecular marker is a particular sequence of DNA that is identifiable within the larger genome. Researchers use molecular markers to keep track of the regions of particular genes within a larger strand of DNA.
With this information in hand, plant breeders can predict how crosses between different lentil varieties are likely to perform in different areas. Bett is using the same technique to identify genes responsible for traits consumers want, such as colour, protein and micronutrient levels.
“We share our information with international gene banks too, so if somebody wants to screen for diseases that affect lentils, they have our information on the genome as a head start,” says Bett. “We’re not competing. We’re collaborating.”
As Genome Canada’s Chief Scientific Officer, I see Bett’s collaborative approach as one of the reasons a federally-funded, national not-for-profit organization such as ours supports her research in advancing food security.
We’re in an era of big data – it’s a critical feature in genomics science and its applications. The more data you have, the greater its power and the better understanding you have. And the better you can address your challenges.
While Bett enjoys the scientific challenge of unlocking that data to safeguard a globally important source of nutrition, she also likes experimenting with lentils in her own kitchen. Red lentil dahl with coconut milk, and French green lentil salad are two of her favourites.
“My kid’s go-to comfort food has been dahl since she was teeny, tiny,” says Bett.
As we celebrate Earth Day this month, it’s a perfect time to think about choosing foods that benefit not only you, but also Mother Earth.
Learn more about the science of genomics and related careers, through Let’s Talk Science