Growth and defense in deciduous trees and shrubs under UV-B.
Reflection by waxy or resinous surface structures and hairs, repair reactions of biomolecules and induction of different sheltering components provide the means of plant protection from harmful solar UV-B radiation. Secondary products, especially flavonoids and phenolic acids as defense components are also important in plant tolerance to UV-B, fulfilling the dual role as screens that reduce UV-B penetration in plant tissues, and as antioxidants protecting from damage by reactive oxidant species. Plants are sensitive to UV-B radiation, and this sensitivity can be even more clone-specific than species-specific. The results available in the literature for deciduous trees and shrubs indicate that UV-B radiation may affect several directions in the interaction of woody species with biotic (herbivores) and abiotic (CO2 and nutrition) factors depending on the specific interaction in question. These multilevel interactions should have moderate ecological significance via the overall changed performance of woody species and shrubs.
Julkunen-Tiitto
Riitta
R
Natural Product Research Laboratory, Department of Biology, University of Joensuu, PO Box 111, FIN-80101 Joensuu, Finland. rjt@joensuu.fi
Häggman
Hely
H
Aphalo
Pedro J
PJ
Lavola
Anu
A
Tegelberg
Riitta
R
Veteli
Timo
T
D000397:Air Pollution / Q000009:adverse effects; D000821:Animal Feed; D000818:Animals; D018533:Biomass; D017753:Ecosystem; D018515:Plant Leaves / Q000254:growth & development / Q000528:radiation effects; D018521:Plant Physiological Phenomena / Q000528:radiation effects*; D012621:Seasons; D014197:Trees / Q000528:radiation effects; D014466:Ultraviolet Rays / Q000009:adverse effects*