Heat waves hurt maize crops more than dry air in Northeast China

Northeast China grows a lot of corn—about a third of the country’s total. But the weather there has been getting more extreme. Scientists looked at 40 years of corn harvests, plant growth records, and weather data from local stations. Instead of blaming just rainfall or drought, they tested how heat and dry air together affect corn each season. Using a smart computer method, they found that unusually hot days during the corn’s flowering time caused the biggest drops in yield. Dry air ranked second but often happened at the same time as heat waves.Corn plants in the northern province of Heilongjiang suffered the most. Their yields fell almost twice as much as in other provinces. The research suggests that when both heat and dryness spike, corn can’t cool itself or hold onto water. That double trouble may explain why Heilongjiang’s crops suffered more damage. Knowing this helps farmers plan better watering and planting times to reduce losses. This study shows that simple weather averages aren’t enough to predict harvests. Nights that stay warm, days that spike above 35°C, and air that feels extra dry can all hurt corn in different ways. Researchers say future corn varieties and farming rules should focus on handling heat first, then dryness, to keep food supplies steady.