Air Pollution: Effects on Plants

Plants may be affected by relatively low concentrations of pollutants and can serve as a kind of early warning system for the buildup of noxious chemicals in the air. The pollutants discussed were ozone, sulfur dioxide, nitrogen dioxide, and peroxyacetyl nitrate (PAN). These pollutants produce leaf damage and injure grapes, navel oranges, and alfalfa. Many of these oxidants are produced by automobile exhaust. There is evidence that combinations of the pollutants can produce greater effects than individuals, if in the same concentration. The use of antioxidants to retard the action of oxidants is considered. Since chemical treatments are all expensive, use of pollution-resistant plants appears to be a more economical approach. There are marked variations in the susceptibilities of different plant strains to the effects of a given pollutant. 1 figure.