The future of sweet corn turns sour

If you’re a fan of corn on the cob in the US, then you’re likely to have to dig deeper into your pockets to pay for it. Research in Scientific Reports shows that Zea mays yields drop dramatically when temperatures exceed 30°C during flowering. The US Global Change Research Program predicts 20 to 30 more days over 32 C [about 90 F] by mid-century across much of the U.S.

“The reality is that producing sweet corn, one of the most popular vegetable crops in the U.S., will be more difficult in the future. We need to develop new approaches and technologies to help crops adapt to climate change,” says Daljeet Dhaliwal, former graduate research assistant and lead author on the study.

“Our analysis reveals that small temperature changes have a greater influence on crop yield compared to small precipitation changes for both rainfed and irrigated fields in the Midwest and Northwest, but rainfed production shows greater sensitivities,” co-author Martin Williams says.

“If there’s a bad time for extreme heat, it’s during flowering. That’s especially true in a crop where ear quality is so important. With heat stress during flowering, you can have ears with fewer kernels or very misshapen kernels that look nothing like what the consumer is expecting.”

Our analysis, using the whole distribution of growing season temperatures, showed that temperatures ranging from 8 to 30 ∘C∘C represent ‘benign’ growing conditions for sweet corn. Previous empirical studies conducted under controlled environmental conditions have determined the same range of temperatures beneficial for field corn growth and development… This is worrisome as the recent trends toward colder, wetter Midwest spring weather often results in delayed spring planting, thereby exposing the crop to hot summer weather for a longer duration.

Dhaliwal & Williams 2022.

📰 Press Release at Eurekalert.
🔬 Research: Evidence of sweet corn yield losses from rising temperatures at Scientific Reports.