Effects of low levels of ozone on growth of crimson clover and annual ryegrass

Journal Article · Fri Dec 31 23:00:00 EST 1976 · Crop Sci.; (United States)

DOI:https://doi.org/10.2135/cropsci1977.0011183X001700030025x· OSTI ID:5061302

Bennett, J P ^[1]; Runeckles, V C

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1. Univ. of California, Davis

Studies have been conducted on short term exposure of plants to broad ranges of O/sub 3/ concentration. Our purpose was to investigate long term exposure of plants to O/sub 3/ levels that were below those normally causing visible injury. Annual ryegrass (Lolium multiflorum Lam.) and crimson clover (Trifolium incarnatum L.) were grown for 6 weeks in chambers within a greenhouse and fumigated for 8 hours/day with 0.03 and 0.09 ppM O/sub 3/ in air. Treated plants showed less growth and yield than the controls despite the absence of visible injury. Both total dry weight and leaf area of treated plants were as much as 22% lower than the controls, but percent dry weight was significantly higher. Root growth was impaired the most, followed by stems and leaves, respectively, as evidenced by a lower root/shoot ratio and a slightly higher leaf weight ratio with O/sub 3/ treatment. Both species showed significantly lower specific leaf areas and leaf area ratios in O/sub 3/ compared to the control, but higher net assimilation rates led to relative growth rates which were unaffected. It was concluded that although the relative size of the leaf system was very sensitive to prolonged exposure to low O/sub 3/, compensation in growth parameters occurred to counteract the stress response.

• OSTI ID: 5061302
• Journal Information: Crop Sci.; (United States), Journal Name: Crop Sci.; (United States) Vol. 17:3; ISSN CRPSA
• Country of Publication: United States
• Language: English

Related Subjects

560303* -- Chemicals Metabolism & Toxicology-- Plants-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AIR POLLUTION
BIOLOGICAL EFFECTS
BIOMASS
CEREALS
CLOVER
ECOLOGICAL CONCENTRATION
ENERGY SOURCES
GRAMINEAE
GRASS
GROWTH
LEGUMINOSAE
OZONE
PLANT GROWTH
PLANTS
POLLUTION
PRODUCTIVITY
RENEWABLE ENERGY SOURCES
ROOTS
RYE