Avtor/Urednik		Trošt, Tadeja; Gaberščik, Alenka
Naslov		The effect of enhanced UV-B radiation on Norway spruce (Picea abies (L.) Karst.) needles of two different age classes
Prevedeni naslov		Vpiv povečanega UV-B sevanja na iglice smreke (Picea abies (L.) Karst.) dveh starostnih razredov
Tip		članek
Vir		Acta Biol Slov
Vol. in št.		Letnik 44, št. 3
Leto izdaje		2001
Obseg		str. 13-25
Jezik		eng
Abstrakt		The present study reports the effects of enhanced UV-B radiation on Norway spruce (Picea abies (L.) Karst.) in relation to the aging of needles. Plants were exposed to reduced and ambient UV B levels and to a UV-B level simulating 17% ozone depletion. The following parameters were monitored: light saturated photosynthetic activity and photochemical efficiency (Fv/Fm, Y, NPQ), potential respiration, total chlorophyll content and chlorophyll a/b ratio, and methanol soluble UV-B absorbing compounds. The experiment revealed that Norway spruce is quite tolerant to enhanced UV-B radiation. Developing young needles were revealed to be the most vulnerable since the efficiency of screening is more dependent on the developmental state of the leaf than induced by enhanced UV-B radiation.
Izvleček		Ugotavljali smo vpliv povečanega UV-B sevanja na smreko (Picea abies (L.) Karst.) glede na različno starost iglic. Spremljali smo fotosintezno aktivnost, fotokemično učinkovitost fotosistema II, dihalni potencial, vsebnost UV-B absorbirajočih snovi in fotosinteznih barvil. Dodatno UV-B sevanje tekom ene vegetacijske sezone ni imelo jasnega negativnega učinka na rastline. Značilne razlike med tretiranji s povečanim in zunanjim UV-B sevanjem smo izmerili na mladih iglicah v prvih tednih razvoja, ko UV-B absorbirajoče snovi in drugi zaščitni mehanizmi še niso popolnoma razviti.
Deskriptorji		TREES ULTRAVIOLET RAYS PHOTOSYNTHESIS CHLOROPHYLL ELECTRON TRANSPORT SEASONS