Potato crops do not perform well in high temperatures, according to a new research paper, and that could be a problem as the weather warms with climate change.
Om Rajora, one of the authors of the study, said they tested 55 different varieties, or cultivars, of potatoes, including russet Burbank, a workhorse of the potato industry.
The study was published earlier this month in Canadian Science Publishing’s Botany journal.
None of the cultivars performed very well. The plants actually grew bigger in the heat, but the key factor for farmers — tuber production — fell dramatically.
“The plants increased their chlorophyll content overall, but potato tuber yield decreased by 93 per cent,” said Rajora, who is a professor at the University of New Brunswick.
“Some of the cultivars did not even form a tuber.”
Even the best-performing cultivars had a 70 per cent reduction in yield. The russet Burbank produced just one tuber.
The researchers grew half the cultivars in daytime temperatures of 35 C and nighttime temperatures of 28 C. The control group was grown in 18 C to 22 C temperatures, closer to the climate where potatoes evolved in the Andes in South America.
“We have already seen these conditions that were created here in our experiment,” said Rajora.
“We have seen those 34, 35 degrees in Ontario, and potato production has gone down.”
Rajora does not believe any of the cultivars that were tested would be viable for sustainable potato production under the heat conditions tested.
The P.E.I. Potato Board says it is already aware that the industry is facing potential problems with climate change.
Executive director Greg Donald said the group has been lobbying Agriculture and Agri-Food Canada to research new cultivars that are better adapted to the future Canadian climate, and that some newer varieties from western U.S. breeding programs have been trialled.
“We really need [Agriculture and Agri-Food Canada] to develop a variety that’s bred for Canadian growing conditions which are quite different than the western U.S.,” Donald wrote to CBC News.
“We need short season, big yielder that works well with rain-fed systems and increasingly erratic weather patterns.”