Ozone inhibition of transpiration and photosynthesis

Journal Article · Wed Jan 01 04:00:00 EST 1975 · Agron. J.; (United States)

OSTI ID:6374740

Yingjajaval, S; Boersma, L; Tingey, D

Transpiration, net photosynthesis, and ozone uptake were measured during four hour exposures of soybean leaves to ozone concentrations ranging from 0 to 60 pphm. The cultivars Hood and Dare were studied at plant ages of 14 and 20 days. Injury was a function of ozone concentration and length of exposure. Effects on Tr and Pn rates at O/sub 2/ concentrations <40 pphm appeared to be due largely to stomatal closure. Young plants recovered when the O/sub 3/ was removed. An increase in compensation point suggested that the photosynthetic process per se was damaged in the older plants at the high concentrations. This damage was severe and irreversible. Hood, a resistant cultivar in comparison with Dare, a sensitive cultivar, had an initially more rapid decrease in Tr and Pn. However, Hood absorbed less O/sub 3/ during the four hour exposure period. The faster closure of stomatal apertures apparently is an important mechanism in protection against ozone damage.

• OSTI ID: 6374740
• Journal Information: Agron. J.; (United States), Journal Name: Agron. J.; (United States) Vol. 67; ISSN AGJOA
• Country of Publication: United States
• Language: English

Related Subjects

560303* -- Chemicals Metabolism &amp; Toxicology-- Plants-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BACTERIA
BIOLOGICAL EFFECTS
BIOLOGICAL FUNCTIONS
CHEMICAL REACTIONS
COMPARATIVE EVALUATIONS
DOSE-RESPONSE RELATIONSHIPS
FUNCTIONS
GLYCINE HISPIDA
INHIBITION
LEGUMINOSAE
MICROORGANISMS
OPENINGS
OZONE
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PLANTS
RHIZOBIUM
STOMATA
SYNTHESIS
TRANSPIRATION
UPTAKE