Response of Bean and Tobacco to Ozone: Effect of Light Intensity,Temperature and Relative Humidity

Pinto bean (Phaseolus vulgaris, L.) and Bel W₃ tobacco (Nicotiana tabacum, L.) were grown and exposed to 40 pphm ozone for 1 hr under a range of light intensities, temperatures, and relative humidities. Foliar injury to the more sensitive plant leaves was determined on the third day after exposure. Each atmospheric factor was independently assessed. Two significant three-way interactions were found: exposure light intensity by growth light intensity by species, and growth temperature by exposure temperature by species. Three significant two-way interactions were found for humidity: growth humidity by exposure humidity, growth humidity by species, and exposure humidity by species. The sensitivity of each species to ozone changed with changes in each environmental condition.