Secondary metabolites and nutrient concentrations in silver birch seedlings under five levels of daily UV-B exposure and two relative nutrient addition rates
Article first published online: 1 AUG 2002
Volume 150, Issue 1, pages 121–131, April 2001
How to Cite
De La Rosa, T. M., Julkunen-Tiitto, R., Lehto, T. and Aphalo, P. J. (2001), Secondary metabolites and nutrient concentrations in silver birch seedlings under five levels of daily UV-B exposure and two relative nutrient addition rates. New Phytologist, 150: 121–131. doi: 10.1046/j.1469-8137.2001.00079.x
- Issue published online: 1 AUG 2002
- Article first published online: 1 AUG 2002
- Received: 24 July 2000Accepted: 6 December 2000
- Betula pendula;
- exposure-response curves;
- mineral nutrients;
- relative nutrient addition rate;
- secondary metabolites;
- stratospheric ozone depletion;
- UV-B radiation
- • Changes in secondary metabolites in silver birch ( Betula pendula ) seedlings are presented in response to ultraviolet-B radiation (UV-B) and nutrient addition.
- • Concentrations of individual secondary metabolites and nutrients were measured in leaves of greenhouse-grown silver birch seedlings exposed to five time-integrated irradiances of biologically effective UV-B (I BEUV-B ) and fertilized with two relative nutrient addition rates.
- • Several phenolics were not only induced by UV-B, but their concentration was dependent on UV-B daily time-integrated irradiance. Relative nutrient addition rate also affected the concentration of phenolics but had little effect on the UV-B daily time-integrated irradiance-responses. The mineral nutrient concentration of leaves was affected by nutrient addition but not by increasing I BEUV-B . Possible threshold-exposures for the accumulation of secondary metabolites or nutrients were not detected.
- • UV-B and relative nutrient addition rate have mainly an additive (rather than synergistic) effect in silver birch, and leaves respond to increasing UV-B by synthesizing metabolites (e.g. flavonols), which are important UV-B filters. This study reports the first UV-B-exposure-response curves for individual secondary metabolites and nutrients in leaves of a woody tree species.