Rising Temperatures Can Halve Potato Yield, Scientists in China Find Ways to Save Them

Preparing for higher temperatures by the end of the century due to climate change, molecular biologist Li Jieping and his team in Beijing are growing potatoes under conditions that simulate predictions of higher temperatures.

The potatoes harvested are of unusually small size. At just 136g, the vegetable weighed less than half the size of the most popular variety of potato in China which is twice the size of a baseball.

China is world’s largest producer of potatoes, accounting for over 22 per cent of the global production. Hence, it is important for global food security. But the potatoes produced are vulnerable to warmer and wetter conditions. Jieping, a researcher at the International Potato Center (CIP) in Beijing, started a three-year study into the effects of higher temperatures on the vegetable. The study focused on two of the most common varieties in China.

“I worry about what will happen in the future,” Jieping told Reuters. “Farmers will harvest fewer potato tubers, it will influence food security,” he said.

The team grew the crop over three months in a chamber having 3 degrees Celcius higher temperatures than the current average temperature in northern Hebei and inner Mongolia where potatoes are usually grown. The research found that potato growth is accelerated by 10 days but yields are reduced by more than half.

The research by CIP, which is headquartered in Lima, is done in collaboration with the Chinese government to help farmers adapt to climate change, driven by fossil fuel emissions.

The temperatures are set to reach dangerous heights of 3.1 degrees Celcius warming above pre-industrial levels by 2100, according to a United Nations report released in October.

Jieping told Reuters that the Chinese farmers will need to adapt within the next decade by planting during spring instead of the start of summer, or moving to even higher altitudes to escape the heat. He also cautioned that if they don't find solution, farmers will make less money with low yields, leading to increased price of potatoes.

Along with increased temperatures, humid conditions also affect potato yield. In Inner Mongolia, farmers rush to dug up the vegetable from the soil before the next downpour. They are increasingly demanding varieties that are higher-yielding and less susceptible to disease.