About 500 experts in Canadian plant science gathered in Halifax this week for the Plant Canada conference.
The Canadian Societies of Agronomy, Horticultural Science, Plant Physiologists, Phytopathological, Weed Science and the Canadian Botanical Association met to discuss plant adaptation to environmental changes. The societies held some joint meetings and tours of Nova Scotia, but also held their own association meetings and discussed recent research projects and findings within specific fields of research.
David Phillips, senior climatologist with Environment Canada and Paul Bullock of the Department of Soil Science at the University of Manitoba delivered keynote speeches to the group, both noting that climate change and changing weather is having an impact on Canadian crops.
Phillips pointed out that extreme weather events -- ice storms, rain, wind and snow -- are happening more, calling recent meteorological events "an epidemic of ferocious, killer, catastrophic weather everywhere."
At the same time, seasons are more unpredictable, he says, noting that parts of Saskatchewan last year were in drought conditions, while this year, the same areas are flooded. Maple syrup producers used to begin their season when the sap started running on the first day of spring, says Phillips. Over the years, the season has shifted so that 80 per cent are now finished before the start of spring.
He says weather models predict that over time, the seasons will continue to shift and the variability of the weather will increase. That will result in longer growing seasons and more extremes in weather.
Phillips encouraged the plant scientists to continue their research "to try to get more out of the seed," to deal with the expected weather changes.
Bullock weighed the pros and cons of climate change on Canadian crops, listing yield loss, increased aridity, more severe or frequent droughts, breed tolerance to more pests and poor rainfall distribution as some concerns climate change is bringing to researchers. However, positive impacts of climate change could be more heat units, carbon dioxide stimulation of yields, northward expansion to suitable cropping areas, improved water use efficiency, deeper roots and warmer soil.
Weeds are also expected to be impacted with climate change, he notes.
"In most cases, weeds come out the winner," Bullock says, noting that current controls may not continue to be a solution. Glyphosate efficacy has dropped when there is an increase in carbon dioxide, one of the effects of climate change. "That's a bit of a cause for concern."
Precipitation, he says, is harder to predict.
"This is where we have some of the poorest knowledge about what to expect," Bullock says, noting that many studies predict "potentially longer dry periods between less frequent but more intense precipitation."
"That's not a good thing. That's a poor rainfall distribution that tends to be negative for crop yields."
Overall, Bullock says, the pros and the cons of climate change on Canadian crops are close to even.
"There is definitely some positive potential, but some negative. Where it all shakes down, I don't know," he says.