Plant Responses to Ozone
In the layer of the atmosphere closest to the Earth’s surface, ozone is a gaseous air pollutant created when sunlight reacts with chemical compounds in vehicle exhausts, industrial emissions, and chemical solvents. Ozone can severely damage plants and is a serious concern for farmers, forest and plant nursery managers, park managers and visitors, landscapers and gardeners, and consumers across the U.S. Ozone-sensitive plants include major crops (e.g., barley, bean, cotton, grape, oat, peanut, potato, soybean, tomato, and wheat) and many important tree species (e.g., aspen, birch, cottonwood, Ponderosa pine, black cherry, white ash, sycamore, and yellow poplar). Chronic exposure to ozone injures the leaves of sensitive plants and can reduce plant growth, quality, seed production, and tolerance to insects, pathogens, weather, and other stress factors. Current estimates suggest that ozone causes three to five billion dollars in crop loss annually. Considerable visible damage has also been noted among native plants in wilderness areas and recreational areas. Damage to plants in both managed and natural settings can lead to poor soil and water quality and can affect organisms that rely on plants for food, shelter, and other uses. By collaborating across multiple disciplines and states, researchers can get a more complete picture of the factors involved in ozone damage. Scientific data will help estimate economic costs, project future impacts, set air quality regulations, and protect U.S. crops, forests, and other plants.