Avtor/Urednik		Bavcon, J; Druškovič, B; Gogala, N
Naslov		Five year effects of ultraviolet-B irradiation on Norway spruce Picea abies (L.) karts. seedlings
Tip		članek
Vir		In: Guttenberger H, Borzan Ž, Schlarbaum SE, et al, editors. Cytogenetic studies of forest trees and shrubs: review, present status, and outlook on the future. Proceedings of the 2nd IUFRO cytogenetics working party S2.04.08 symposium; 1998 Sep 6-12; Graz. Zvolen: Arbora publishers,
Leto izdaje		2000
Obseg		str. 21-6
Jezik		eng
Abstrakt		The effects of five years of continuous ultraviolet-B (UV-B) irradiation at different intensities the stem length and mitotic activity of Norway spruce (Picea abies) seedlings were studied. We tested the hypothesis that UV-B radiation is one of the primary factors that influence growth and damage young spruce seedlings at higher altitudes. The seedlings were grown in greenhouses and divided into three treatments: control with ambient levels of UV-B (11.7+-5.2kj/m-2), UV-B exposure at 21.24 +- 3.5 kJ/m-2, and UV-B exposure at 31.9 +-2.5 kJ/m-2 (UV-B according to the Delta-T device UV-B sensor). Osram Ultravitalux 300W elongated light bulbs were used as the source of irradiation. After five years of exposure to radiation, spruce seedlings were found to be sensitive to UV-B radiation. There was a significant decrease in the mitotic activity of the cells of the root meristems that characteristically diminished throughout the following year in comparison to the control treatment. Additionally, the seedlings exposed to higher levels of UV-B showed poorer growth of shoots.
Deskriptorji		TREES ULTRAVIOLET RAYS MITOTIC INDEX SEEDS