Reduction in Soybean Seed Yields by Ozone Air Pollution*

Abstract

The National Crop Loss Assessment Network (NCLAN) determined that soybeans were more sensitive to ozone than other major agricultural crops, including corn, wheat, and cotton. The estimated production losses for soybeans at ambient levels of ozone ranged from 7.9 to 18.6 percent compared to 0.6 to 3.1 percent for corn. The research on soybeans was conducted in Illinois, North Carolina, Maryland, and New York. The loss estimates were obtained from field experiments using open-top chambers with charcoal-filtered (CF) air, nonfiltered (NF) air, and NF air with the addition of two or more increments of ozone. However, New Jersey scientists in two recent reports question the validity of the NCLAN results since the utilization of a different method to assess the impact of exposure of ambient O/sub 3/ on soybeans failed to show significant yield losses.