Leaf structure of Poa annua with observations on its smog sensitivity in Los Angeles County

Journal Article · Sun May 01 04:00:00 EDT 1955 · Am. J. Bot.; (United States)

DOI:https://doi.org/10.2307/2438796· OSTI ID:5318869

Bobrov, R A

Annual bluegrass (Poa annua L.) is very sensitive to certain phytotoxic agents present in smog and might be useful as a bioassay indicator plant. In the field, the characteristic response to hydrocarbon-oxidation products is seen to be a tan spotting or transverse banding limited to the region between tip and midblade of susceptible leaves. This damage has been duplicated in the laboratory with synthetically-produced smog. Tissue damage is similar to that previously described in spinach, beets, oats and other plants. The cells which are initially and most seriously damaged are those surrounding the substomatal chambers. Chloroplasts disintegrate, plasmolysis follows, and ultimate total dehydration of damaged cells results in part or all of the mesophyll tissue in affected areas becoming mummified. In plants having a high specific sensitivity to smog, damage is correlated with stomatal distribution and activity, volume of intercellular air space and age of cells. Localization of damage is related to the gradient of cellular differentiation from tip to base in the linear leaf; the sensitive region is limited to those cells which have just completed maximum expansion. 18 references.

• Research Organization: Los Angeles County Air Pollution Control District, CA
• OSTI ID: 5318869
• Journal Information: Am. J. Bot.; (United States), Journal Name: Am. J. Bot.; (United States) Vol. 42; ISSN AJBOA
• Country of Publication: United States
• Language: English

Related Subjects

500200 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
560303* -- Chemicals Metabolism & Toxicology-- Plants-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOLOGICAL EFFECTS
BIOLOGICAL INDICATORS
CALIFORNIA
CELL CONSTITUENTS
CHLOROPLASTS
DATA
EXPERIMENTAL DATA
FEDERAL REGION IX
GRASS
GROWTH
INFORMATION
LEAVES
MORPHOLOGICAL CHANGES
MORPHOLOGY
NORTH AMERICA
NUMERICAL DATA
OPENINGS
PLANTS
SENSITIVITY
SMOG
STOMATA
ULTRASTRUCTURAL CHANGES
USA