Drought, ozone pollution team up to reduce soybean yield

In a decisive new study, crop scientists at the University of Illinois Urbana-Champaign and the U.S. Department of Agriculture’s Agricultural Research Service show that soybeans are doubly damaged by drought and ozone pollution, both of which are increasing across the globe due to climate change.

The study settles the question of whether drought stress actually could protect soybean plants from the damaging effects of ozone, which include leaf bronzing, leaf drop and yield loss.

Here’s the logic: Leaves are speckled with thousands of tiny openings called stomata that let carbon dioxide in and water vapor out. When they sense drought, plants close their stomata to conserve water. Some early studies suggested that by causing stomata to close, drought also may prevent ozone from entering le