title: Long-term ozone exposure of potato: free radical content and leaf injury analysed by Q-band ESR spectroscopy and image analysis.
abstract: This paper presents Q-band electron spin resonance (ESR) studies on free radicals (FR) generated in potato leaves exposed to different O(3) levels in open-top chambers (OTC), together with a quantitative study of the relationship between FR signal intensity and area of potato leaf damage. The advantages of Q-band when compared to X-band ESR spectroscopy are analysed, the main advantage being an absence of overlapping between Mn(II) and FR signals, allowing a quantitative study of FR signal intensity. This study also reports on a graphical method developed to quantitatively measure the damaged area on leaves caused by ozone exposure. Results indicate a direct relationship between FR signal intensity (measured as area under the signal) and percentage of O(3) damage and clearly demonstrate a close relationship between visible ozone-induced symptoms and permanent FR concentration in potato leaves.
authors.affiliation: Departamento de Biología Vegetal, Universidad de Valencia, Burjassot, Valencia, Spain. m.amparo.asensi@uv.es
authors.forename: Amparo
authors.initials: A
authors.lastname: Asensi-Fabado
authors.forename: José L
authors.initials: JL
authors.lastname: Carrasco-Rodríguez
authors.forename: Carlos J
authors.initials: CJ
authors.lastname: Gómez-García
authors.forename: Secundino Del
authors.initials: SD
authors.lastname: Valle-Tascón
mesh_terms: D000388:Air / Q000032:analysis; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D005609:Free Radicals / Q000378:metabolism*; D007091:Image Processing, Computer-Assisted; D010126:Ozone / Q000633:toxicity*; D018515:Plant Leaves / Q000528:radiation effects*; D011198:Solanum tuberosum / Q000528:radiation effects*
chemical_list: D005609:Free Radicals; D010126:Ozone