Oak (Quercus robur L.) seedling responses to a realistic increase in UV-B radiation under open space conditions

Plants show different levels of sensitivity to ultraviolet-B (UV-B) radiation and acclimation to high UV-B irradiances had been developed in many species. A field experiment was performed during 1995 to study the adaptive responses of oak plants (Quercus robur L.) to artificial UV-B supplementation. The most important effect of UV treatment was the increase in leaf thickness and the accumulation of phenolic compounds in the secondary wall of the adaxial epidermis of leaves in UV treated plants; the secondary wall of cells in the abaxial epidermis, while plant morphology was sensible to UV treatment.