by Matt McIntosh
Scientists focus on improving water use and breeding more resilient food crops
Innovation in food and farming is a critical way of supporting the United Nations 17 Sustainable Development Goals. Thousands of researchers across Canada collaborate with each other, and with other scientists worldwide, to make farming more productive and affordable, less burdensome on the environment, and more resilient to a challenging climate.
Profiled here are two researchers focused on improving food sustainability in different ways; through improved water use, and more disease-resistant crops.
Dr. Gurcharn Singh Brar, assistant plant science professor at the University of British Columbia
Research focus – more disease-resistant wheat and barley
Historically, the spread of plant diseases can cause severe damage to crops, if not total crop failure. It’s still a problem many people face, particularly in poorer regions. Even in relatively wealthy places like North America, plant diseases can cause significant hardship to farmers and put upward pressure on food prices.
In his lab at the University of British Columbia, Brar and his research colleagues are focused on breeding more disease-resistant wheat and barley – two of the world’s most common and important cereal crops. In his own terms, Brar says their long-term goal is to “strengthen the immune system” of wheat and barley and in doing so, reduce the need for chemical controls – most notably fungicides.
In cereals, fungal pathogens can damage the quality and health of the plant itself. This has financial ramifications for farmers. Some of those fungi also produce toxins, which can be harmful to humans and animals if present in high enough quantities. Fungicides are designed to eliminate fungal pathogens in crops, thus reducing financial and health risks. Fungicides are generally very effective at doing this, but they can be very expensive. Using them too often can also push the targeted fungal pathogen to become resistant to the chemical, forcing farmers to find other means of control.
Developing crops which are themselves more resistant to fungal diseases can help fix these issues before they arise. By identifying wheat and barley genes that show greater resistance to specific diseases, Brar says plant breeders can begin developing new, more resilient varieties of the two crops. Doing this helps overcome current challenges, but also helps insulate crop production against emerging disease pressures.
“In cereals, for example, we are seeing a disease called black chaff, or bacterial leaf streak. It’s normally been confined to North Dakota, South Dakota, Minnesota, and so on, but now we see that disease quite often in southern Manitoba,” says Brar. “Last year and the year before, it was even reported in southern Alberta and parts of Saskatchewan. It’s another disease that might become common as our climate or weather patterns change.”
Brar’s research also includes projects designed to reduce greenhouse gas emissions from nitrogen – nitrous oxide, or the gas form of nitrogen, being a particularly significant greenhouse gas in the agriculture sector. One project, for example, involves increasing the ability of wheat and barley roots to supress nitrification in the soil, thereby keeping nitrogen in ammonium form accessible to crops and preventing it from escaping into the atmosphere as nitrous oxide. To accomplish this, Brar and a wider network of researchers are trying to incorporate genes for the trait from exotic sources into Canadian wheat and barley varieties.
Brar adds transferring knowledge and training the next generation of scientists is a critical part of his work.
“We try to make sure our students are aware of forthcoming issues so they can keep that in mind for future research, and so they can have a visionary approach. They can think and prepare for what the issues will be 40, 50, or 100 years down the road.”
Dr. Phillip Harder, research associate with the Centre for Hydrology, University of Saskatchewan
Research focus: Improving water availability for better crop production and soil health
Crops need water to survive and thrive. In some areas, farmers use irrigation systems to ensure crops receive water throughout the growing season, or at least when they may not be getting enough from rainfall. Most crop production in Canada happens on non-irrigated land, though. On parts of the prairie, where the growing season is often dry, understanding the sources of water and how it moves through the soil can inform farmers on which production methods help or hinder a crop’s ability to access water.
Harder is a hydrologist – someone who studies water and how it moves through the environment. Through technologies ranging from sensors in the field measuring evapotranspiration and soil moisture to remote sensing from drones, Harder measures how moisture can vary across a landscape, and even in the same field.
The moisture variability in a given area can be matched with other factors, such as how much plant matter was left on the soil surface or how much snow fell the previous winter. Doing this makes it possible to, for example, quantify how supporting soil health correlates with moisture availability.
Harder highlights better soil management – namely, not disturbing it as much and leaving more crop residue, such as the unharvested leaves and stalks of a previous crop – as major opportunities for prairie farmers to increase how much water their soils can hold. This is particularly important because, unlike other parts of the country, a meaningful amount of moisture available to crops grown on much of the prairies can come from the previous winter’s snow, not rainfall.
“Plant growth is going to be limited by water, so we should be doing things to increase soil water input and storage. Increasing crop stubble heights in particularly arid areas will increase snowmelt. Increasing soil cover by 10 per cent can reduce soil evaporation in the order of 5 per cent,” says Harder. “There can be an underappreciation for the impact of snow in crop production on the prairies, the problem being it’s so variable. When things are super-wet, snow isn’t the main driver of growth. But when it’s dry, we have data showing 50 per cent of crop growth is from snowmelt and winter moisture.”
“The main principals of improving soil health, like having living roots and ground cover, can be equally be reframed as soil hydrology principals, but the extreme climate and frequent water limitations of the prairies means that soil health principals will look different in this region than warmer and wetter places.”