Co-Authors:
Jansen, M.A.K., Department of Plant Genetics, Weizmann Institute of Science, Rehovot 76100, Israel, Department of Plant Physiology, Wageningen Agricultural University, Arboretumlaan 4, 6703BD Wageningen, Netherlands
Babu, T.S., Department of Plant Genetics, Weizmann Institute of Science, Rehovot 76100, Israel, Department of Biology, University of Waterloo, Waterloo, Ont. N2L 3GI, Canada
Heller, D., Department of Plant Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
Gaba, V., Department of Virology, ARO Volcani Center, Bet Dagan 50250, Israel
Mattoo, A.K., Plant Molecular Biology Laboratory, USDA/ARS, Beltsville Agricultural Research Center, Beltsville, MD 20705, United States
Edelman, M., Department of Plant Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
Abstract:
Ultraviolet-B (UV-B) tolerance in plants has mostly been correlated with the presence of screening pigments (e.g. flavonoids) or other reductions in leaf transmittance. We have exploited the rapid turnover of the Photosystem II reaction center protein D1 as a sensitive in vivo probe for UV-B damage. We found that the aquatic monocot, Spirodela oligorrhiza, protects itself from UV-B irradiance using at least three different mechanisms. In one case, protection is correlated to the presence of UV-B screening pigments; in the second, an elevated oxygen-radical detoxifying system parallels UV-B tolerance; while in a third, UV-B tolerance is related to a mechanism involving neither screening pigments nor increased radical scavenging capacity. This demonstrates that, in vivo, a plant can complement its UV-screening and attenuation strategies by other tactics as well. © 1996 Elsevier Science Ireland Ltd. All rights reserved.