Effects of short-term ozone exposure on net photosynthesis, dark respiration, and transpiration of three eastern white pine clones

• Published in: Environment international 1983, Vol.9 (4), p.265-269
• Main Authors: Yang, Y.S., Skelly, J.M., Chevone, B.I., Birch, J.B.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Metabolism; Metabolism. Physicochemical requirements; Pinus strobus; Plant physiology and development
• ISSN: 0160-4120; 1873-6750
• DOI: 10.1016/0160-4120(83)90084-3

Net photosynthesis, dark respiration, and transpiration rates were determined during ozone (O 3) exposure for three clones of eastern white pine ( Pinus strobus L.) differing in sensitivity to O 3. Fumigations for 4 h with 0.10, 0.20, and 0.30 μL/L O 3 inhibited net photosynthesis of all three clones. Light transpiration was inhibited in both the sensitive and the tolerant clones and was not affected in the intermediate clone. Recovery of net photosynthesis and light transpiration occurred 1 h after the termination of ozonation, with the degree of recovery depending upon clonal sensitivity to O 3 and the O 3 concentration used. Dark respiration increased in the O 3-sensitive clone only, and dark transpiration was unaffected in all three clones after 4-h exposure to 0.30 μL/L O 3. Ozone-induced inhibition of net photosynthesis and stimulation of dark respiration are discussed in relation to clonal sensitivity to O 3.