Sequential reduction of UV-B radiation in the field alters the pigmentation of an Antarctic leafy liverwort
Newsham, K.K.; Geissler, P.A.; Nicolson, M.J.; Peat, H.J.; Lewis-Smith, R.I.. 2005 Sequential reduction of UV-B radiation in the field alters the pigmentation of an Antarctic leafy liverwort. Environmental and Experimental Botany, 54 (1). 22-32. 10.1016/j.envexpbot.2004.05.006Before downloading, please read NORA policies.
UV-B radiation (280–315 nm), incident on the leafy liverwort Cephaloziella varians growing at Rothera Point on the Western Antarctic Peninsula, was manipulated in late austral spring 1998 by screens consisting of a novel combination of Plexiglas panes and polyester sheets. The screens transmitted approximately 79, 68, 48, 41 and 31% of daily UV-B radiation dose. Plants from under and outside the screens were sampled seven times over 35 days. Correlative analyses indicated that concentrations of an anthocyanin-like pigment located in leaf tips were positively associated with UV-B transmission at the last two samplings, that concentrations of total chlorophylls were negatively associated with UV-B transmission at the final sampling, and that those of UV-B screening pigments were positively correlated with transmission at three intermediate samplings. Plants exposed to low UV-B transmission levels were visibly greener than those exposed to high transmission levels after approximately 23 days. The closest relationships between the treatment and concentrations of UV-B screening pigments were associated with increased ambient biologically weighted UV-B dose received by plants in the 5.5 h before each sampling, which coincided with the passage of the ozone hole over Rothera Point. As C. varians emerged from melting snow and ice, concentrations of the anthocyanin-like pigment and chlorophyll respectively increased and decreased faster in plants exposed to high transmission levels of UV-B, relative to those exposed to low UV-B transmission levels.
|Programmes:||BAS Programmes > Antarctic Science in the Global Context (2000-2005) > Antarctic Biodiversity - Past, Present and Future|
|Additional Keywords:||Anthocyanin, Cephaloziella varians, Chlorophyll, Ozone depletion, UV-B screening pigments|
|NORA Subject Terms:||Botany|
|Date made live:||10 Jan 2008 15:13|
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