Correlating physiological parameters with biomarkers for UV-B stress indicators in leaves of grapevine cultivars Pinot noir and Riesling

Abstract

Summary The robustness of seven physiological parameters together with two potential biomarkers for ultraviolet (UV)-B stress assessment was tested in greenhouse assays on the Vitis vinifera L. cultivars Pinot noir and Riesling. Effects of year, UV-B treatment, cultivar and clone were studied in four individual experiments. Grapevine plants were exposed to three dosed UV-B stress treatments (−UV-B: no UV-B radiation; +UV-B: daily dose of 4856·3 J/m 2 UV-B BE ; ++UV-B: daily dose of 7025·3 J/m 2 UV-B BE ) to detect changes of chlorophyll fluorescence and gas exchange parameters. Significant correlations between the leaf polyphenols quercetin-3- O -glucoside and kaempferol-3- O -glucoside with the maximum fluorescence (Fm), the variable fluorescence (Fv) and the maximum quantum yield for photosystem (PS) II (Fv/Fm) were found, which confirmed the biomarkers’ relevance, additionally validated by cultivar- and year-independency.