HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Flagler, R. B. Articles by Youngner, V. B. Search for Related Content PubMed Articles by Flagler, R. B. Articles by Youngner, V. B. Agricola Articles by Flagler, R. B. Articles by Youngner, V. B.

Ozone and Sulfur Dioxide Effects on Tall fescue: I. Growth and Yield Responses¹

ABSTRACT

The effects of ozone (O₃) and sulfur dioxide (SO₂) on growth and yield components of tall fescue (Festuca arundinacea Schreb. ‘Alta’) were studied in a greenhouse experiment. Four O₃ treatments ranging from 0 to 0.30 ppm in equally spaced intervals and two SO₂ treatments, 0 and 0.10 ppm, were arranged factorially in a randomized complete block design utilizing three blocks. Each block was exposed to the pollutants 6 h/d, once a week, for 12 weeks. Statistical analysis was by analysis of variance and regression techniques.

Ozone significantly affected root/shoot ratio and all dry weight fractions. A reduction of total dry weight of 52.5% was found due to 0.30 ppm O₃. A cubic regression model of O₃ concentration on total dry weight accounted for 93% of the variation in total dry weight. Partitioning the dry weight into shoot and root components revealed a reduction in shoot weight of up to 46% and a reduction in shoot weight of up to 46% and a reduction in root weight of up to 63.6% due to the high-O₃ treatment. Both variables had significant cubic regressions of O₃ on dry weight with the cubic model accounting for 93 and 89% of the variation in shoot and root weights, respectively. Root/shoot ratio declined from 0.58 for control plants to 0.41 for plants exposed to 0.30 ppm O₃. A significant cubic regression of O₃ on root/shoot ratio accounted for 78% of the variation in this variable. Tiller weight was also affected adversely by O₃ with a linear decrease (r² = 0.85) of > 44% at the highest O₃ level. SO₂ also affected tall fescue, but not nearly as severely as O₃. Total dry weight was reduced by 7.3% due to SO₂. Root weight was decreased by 11%, but shoot weight was unaffected. Root/shoot ratio was lowered about 7% due to the pollutant. Weight per tiller was unaffected by SO₂. Number of tillers was significantly reduced by an interaction of the two pollutants. Neither O₃ or SO₂ had an effect singly, but at the high O₃ level, the addition of SO₃ caused an 18.6% reduction in number of tillers. This was the only significant pollutant interaction noted.

Key Words: Festuca arundinacea Schreb. • ‘Alta’ tall fescue • pollutant interaction

¹ Contribution of the Dep. of Botany and Plant Sciences, University of California, Riverside, CA 92521.

² Staff Research Associate and Professor of Agronomy, respectively.

Received for publication September 14, 1981.