Study Finds Sweet Corn Yields Drop with Extreme Heat

A study published by University of Illinois researchers found that sweet corn yields drop significantly in rainfed fields as a result of extreme heat during flowering. With 20 to 30 more days of extreme heat predicted per summer by mid-century in the Midwest, researchers predict that growing sweet corn is likely to become much more difficult. “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 lead study author Daljeet Dhaliwal. Comparisons using 27 years of sweet-corn production data showed that even small temperature changes affected yields more than variations in precipitation. In rainfed regions in particular, every degree day over 30 C during flowering led to an additional yield loss of 2%, but more than one day at 40 C could cause yield to drop by 20%.