Research Article
Incidence of Ozone Injury on Hybrid Poplar Trees in Southwestern Pennsylvania USA: A 26-Year Field Study
Davis DD1*, Marini RP2 and Decoteau DR2
1Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, USA
2Department of Plant Science, The Pennsylvania State University, USA
*Corresponding author: Davis DD, Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, University Park, PA, USA; E-mail: ddd2@psu.edu
Copyright: © Davis DD, et al. 2020. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Article Information: Submission: 11/11/2020; Accepted: 14/12/2020; Published: 17/12/2020
Abstract
During 1991 to 2016, we evaluated the annual incidence (percentage) of hybrid poplar trees exhibiting ozone (O3)-induced leaf injury (stipple) within 15 planted field-study plots in southwestern Pennsylvania, USA. Incidence of stippled poplars decreased from a mean of 3.84% in 1991 to 0.00% in 2016. Mean
annual 8-hr ambient O3 concentrations, downloaded from a U.S. EPA monitoring site located ca 60 km west (upwind) from the closest study plot, decreased from 96 ppb in 1991 to 67 ppb in 2016. Regression analysis revealed that during the 26-year period, the annual incidence of poplar trees exhibiting ozoneinduced
leaf stipple was significantly and linearly related to the mean annual O3 concentration.