Response of kidney bean to sequential ozone exposures

• Published in: Environmental and experimental botany Vol. 28; no. 4; pp. 307 - 313
• Main Authors: McCool, P.M., Musselman, R.C., Younglove, T., Teso, R.R.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 1988
• Subjects: dose; exposure dynamics; Phaseolus vulgaris; Phaseolus vulgaris; dose; exposure dynamics
• ISSN: 0098-8472; 1873-7307
• DOI: 10.1016/0098-8472(88)90054-8

Predisposition of plants to injury or growth effects from consecutive exposures is an important concept in that multiple exposures cannot be represented by simply adding a series of independent events. The independence of individual exposures in a sequence of exposures was investigated. Red kidney bean was exposed to 0.30 ppm (599 μg/m 3) ozone for 3 hr at 12 days of age. Subsequent second exposures of the same dose were applied at 13, 14, 15, 16, 17 or 18 days of age. Piecewise linear regressiion analysis indicated that plants became tolerant or desensitized to second fumigations if the exposures were closely spaced. After a discrete interval between exposures, plants again exhibited detrimental growth effects. In separate experiments, an interval of 3 or 5 days between exposures was necessary to detect a detrimental growth response in stem, leaf and total dry weight parameters. Leaf area did not exhibit consistent responses to a second ozone exposure in any treatment. Implications of the recovery period to plant response and experimental fumigation designs are discussed.