Research Finds Some Crops Tolerate Ozone Pollution Better than Others

Differences in crop plants can make them more or less prone to harm caused by ground-level ozone pollution, according to a recent Proceedings of the National Academy of Sciences paper published by a team of Agricultural Research Service (ARS) and University of Illinois scientists in Urbana-Champaign (UIUC). The findings&mash;that so-called “C4” crops like corn and sorghum tolerate increased ozone levels better than “C3” crops, like rice or snap beans—open the door to better models for predicting crop responses to the effects of global climate change, as well as developing more resilient varieties. A crop is designated as C3 or C4 depending on whether the CO2 it captures from the air is initially converted into a 3-carbon or 4-carbon compound. Specifically, this analysis focused on the responses of five C3 crops (chickpea, rice, snap bean, soybean, and wheat) and four C4 crops (sorghum, corn, giant miscanthus, and switchgrass) to both ambient levels of ozone and increased concentrations of the gas, ranging from 40 to 100 parts per billion.