title: Assessment of UV biological spectral weighting functions for phenolic metabolites and growth responses in silver birch seedlings.
abstract: In research concerning stratospheric ozone depletion, action spectra are used as biological spectral weighting functions (BSWFs) for describing the effects of UV radiation on plant responses. Our aim was to evaluate the appropriateness of six frequently used BSWFs that differ in effectiveness with increasing wavelength. The evaluation of action spectra was based on calculating the effective UV radiation doses according to 1-2) two formulations of the generalized plant action spectrum, 3) a spectrum for ultraviolet induced erythema in human skin, 4) a spectrum for the accumulation of a flavonol in Mesembryanthemum crystallinum, 5) a spectrum for DNA damage in alfalfa seedlings and 6) the plant growth action spectrum. We monitored effects of UV radiation on the concentration of individual UV absorbing metabolites and chlorophyll concentrations in leaves and growth responses of silver birch (Betula pendula) seedlings. Experiments were conducted outdoors using plastic films attenuating different parts of the UV spectrum. Chlorophyll concentrations and growth were not affected by the UV treatments. The response to UV radiation varied between and within groups of phenolics. In general, the observed responses of phenolic groups and individual flavonoids were best predicted by action spectra extending into the UV-A region with moderate effectiveness.
authors.affiliation: Department of Biological and Environmental Sciences, University of Jyväskylä, Jyväskylä, Finland. titta.kotilainen@helsinki.fi
authors.forename: Titta
authors.initials: T
authors.lastname: Kotilainen
authors.forename: Tuulia
authors.initials: T
authors.lastname: Venäläinen
authors.forename: Riitta
authors.initials: R
authors.lastname: Tegelberg
authors.forename: Anders
authors.initials: A
authors.lastname: Lindfors
authors.forename: Riitta
authors.initials: R
authors.lastname: Julkunen-Tiitto
authors.forename: Sirkka
authors.initials: S
authors.lastname: Sutinen
authors.forename: Robert B
authors.initials: RB
authors.lastname: O'Hara
authors.forename: Pedro J
authors.initials: PJ
authors.lastname: Aphalo
mesh_terms: D029662:Betula / Q000737:chemistry* / Q000254:growth & development / Q000378:metabolism*; D004307:Dose-Response Relationship, Radiation; D010126:Ozone / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry* / Q000378:metabolism; D036226:Seedlings / Q000737:chemistry* / Q000254:growth & development / Q000378:metabolism*; D014466:Ultraviolet Rays
chemical_list: D010636:Phenols; D010126:Ozone