Plants ozone damage

Dugger, W. M., Ir., O. C. Taylor, E. Cardiff, and C. R. Thompson. Relationship between carbohydrate content and susceptibility of pinto bean plants to ozone damage. Proc. Amer. Soc. Hort. Sci. 81 304-314, 1962. 

Jones, J. L. Ozone damage Protection for plants. Science 140 1317-1318, 1%3. 

Rich. S.. and G. S. Taylor. Antiozonants to protect plants from ozone damage. Science 132 150-151, 1960. 

Treshow, M. Ozone damage to plants. Environ. Pollut. 1 155-156, 1970. 

In conclusion, it is our view that K+ plays a dominant role in maintaining a favorable plant cell water status and that the deleterious effects of ozone occur primarily due to disruption of this normal ionic balance. We currently visualize the following scheme of ozone damage (a) ozone attack of an SH group or fatty acid residue (b) permeability changes of the membrane leading to loss of both K" " and osmotic water (c) inhibition or loss of K" " pump activity for reacquisition of lost K+ (d) loss of a critical level of ion and (e) gross disruption of cellular metabolism. 

In Connecticut, ozone injury was first seen on tobacco 20 years ago. This shade-grown crop used for cigar wrappers has an annual cash value of about 22 million. In some years, ozone damage caused a loss of up to 5 million. Plant breeders soon produced cultivars both highly resistant to ozone and yet with the necessary commercial qualities. With the adoption of these cultivars, annual losses to the Connecticut tobacco crop from ozone dropped to only a few thousand dollars, even though the level of pollution did not recede. 

This kind of experiment was performed in an attempt to show that reduction in labelled amino acid uptake into the soluble pool, observed after as little as 15 min of ozonation (Fig. 6), could be an early or primary event in ozone damage to the soybean trifoliate leaf. It was necessary in this case for the pools to be loaded with unlabelled casein hydrolysate after treatment of the plant, in order to maintain vivo ozone treatment and because it has been reported that high endogenous amino acid levels can confer a degree of resistance to ozone damage (14, 15). 

Loreto F, Velikova V. Isoprene produced by leaves protects the photosynthetic apparatus against ozone damage, quenches ozone products, and reduces lipid peroxidation of cellular membranes. Plant Physiol. 2001 127 1781-1787. 

Prevention and Control Ozone levels in the air may reach damaging levels during the hot, calm days of mid- to late summer. Automobile exhaust is a major source of ozone pollution. There is no cure for ozone damage. Avoid it in following years by planting less-susceptible plants, including beets, lettuce, and strawberries. 

Let us use as an example one recent environmental case history relevant to petrochemicals production. Nitrous oxide (N2O) is implicated as a contributor to stratospheric ozone damage, and is also a potent greenhouse gas (Table 2.7). Recent work indicated that about 10% of the nitrous oxide contributions to the atmosphere was from the world s adipic acid plants, slightly more than the fraction contributed by biomass burning [31, 32]. It has been estimated that about 1 mol of N2O is produced per mole of adipic acid, or about 0.3 kg of N2O per kg of adipic acid. 

It has been suggested that volatile terpenes play a similar dual action inside the leaves and participate in ozone quenching in the intercellular spaces before they are released into the atmosphere. In plants exposed to ozone either a reduction or an increase of isoprene and monoterpene emission is observed. Particularly high ozone concentrations induce the terpene emission often as a result of cellular damage. There is evidence that volatile terpenes are able to reduce ozone damage and to quench ozone and reactive oxygen species (ROS). Furthermore, it has been demonstrated in tropical forests a large fraction of total plant sesquiterpene... 

Ozone damages leaf tissue. Leaves may become mottled with yellow, exhibit small black or white spots, develop larger bronze-colored, paper-thin areas, or exhibit other visible symptoms. Inside the leaf, ozone can inhibit metabolic activity, destroy the walls of cells, damage chlorophyll, and reduce photosynthesis. The plant as a whole may grow 10—40 percent more slowly, age prematurely, lose its leaves during the growing season, and produce pollen with a shorter life span. 

Pines. Calorimetric studies of growth rates and temperature responses have not been employed to examine pine trees. Two studies were conducted to analyze effects of air pollutants on the respiration properties of Ponderosa and Jeffrey pine needles. Bower [104] used one-cm needle segments and demonstrated a correlation between the extent of ozone damage, measured as the number of lesions on the needles, and isothermal metabolic heat rates. He also measured increases in metabolic heat rates resulting from acid and nitrate deposition on the needles. Momen et al. [105] conducted a more controlled study of acid rain and ozone effects on Ponderosa pine with defined applications to plantation grown plants. In seedlings, metabolic heat rates increased in response to ozone and combinations of ozone and acid rain. Mature tree metabolic activities showed no response to ozone, acid, or combinations of the two. No studies were made to determine whether metabolic efficiencies were altered by these treatments. Thus the results show that calorimetry can be used to monitor pollutant effects on trees, but more definitive experiments must be done to identify how the ob.served responses relate to growth and survival of the trees. 

Depletion of the Ozone Layer. As a constituent of the atmosphere, ozone forms a protective screen by absorbing radiation of wavelengths between 200 and 300 nm, which can damage DNA and be harmful to life. Consequently, a decrease in the stratospheric ozone concentration results in an increase in the uv radiation reaching the earth s surfaces, thus adversely affecting the climate as well as plant and animal life. Pot example, the incidence of skin cancer is related to the amount of exposure to uv radiation. 

The pollutants most strongly damaging to human, animal, and sometimes plant health include ozone, fine particulate matter, lead, nitrogen oxides (NO ), sulfur oxides (SOJ, and carbon monoxide. Many other chemicals found in polluted air can cause lesser health impacts (such as eye irritation). VOC compounds comprise the bulk of such chemicals. Formaldehyde is one commonly mentioned pollutant of this sort, as is PAN (peroxyacyl nitrate). Such... 

Calorimetry shows that the rates of metabolism of plant tissues vary widely with species, with cell types, and with environmental conditions. This provides a means of exploring the mechanisms by which various agents influence the health of a plant community. Studies are being done on beneficial agents such as growth promoters and detrimental ones such as atmospheric pollutants. For example, a correlation has been found between the metabolic heat rates and the extent of damage to pine needles by ozone. 

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