Can a Forest Tree Species Progeny Trial Serve as an Ex Situ Collection? A Case Study on .

Scientifically informed decisions for the long-term conservation of extant genetic diversity should combine in situ and ex situ conservation methods. The aim of the present study was to assess if a progeny plantation consisting of several open pollinated (OP) families and established for breeding purposes can also serve as an ex situ conservation plantation, using the case study of a Lithuanian progeny trial of , a keystone species of riparian ecosystems that warrants priority conservation actions. We employed 17 nuclear microsatellite (Simple Sequence Repeat) markers and compared the genetic diversity and copy number of the captured alleles of 22 OP progeny families from this plantation, with 10 wild populations, originating from the two provenance regions of the species in Lithuania.

Response of juveniles of seven forest tree species and their populations to different combinations of simulated climate change-related stressors: spring-frost, heat, drought, increased UV radiation and ozone concentration under elevated CO level.

The study aimed to assess response of juvenile progeny of seven forest tree species, Pinus sylvestris, Picea abies, Betula pendula, Alnus glutinosa, Populus tremula, Quercus robur and Fraxinus excelsior, and their populations to different combinations of climate change-related multiple stressors, simulated in a phytotron under elevated CO concentration: (1) heat + elevated humidity (HW); (2) heat + frost + drought (HFD); (3) heat + elevated humidity + increased UV-B radiation doses + elevated ozone concentration (HWUO); and (4) heat + frost + drought + increased UV-B radiation doses + elevated ozone concentration (HFDUO). Effects of the complex treatments, species and species-by-treatment interaction were highly significant in most of the growth, physiological and biochemical traits studied, indicating general and species-specific responses to the applied treatments. For deciduous trees, height increment was much higher under HW treatment than in ambient conditions (control) indicating a positive effect of elevated temperature and better water and CO availability.