Provenance trials with forest trees provide valuable information about growth and adaptability of populations often transferred over large geographical and climatic distances. In this study we evaluated growth and survival of 19 Scots pine (Pinus sylvestris L.) populations representing most of the natural range of the species in Europe, growing in a 30-year-old provenance trial in the northeastern Poland. We used cluster analysis to investigate differentiation among those populations in growth and survival. We also used published data on needle morphology and allozyme and DNA marker variation for those same populations to compare groupings of populations based on growth and needle traits and markers.We found significant variation among tested populations in all investigated traits -the largest variation was found for stand volume which integrates information on growth and survival. Variation in growth traits was related to the latitude of population origin with populations from the latitudinal band between 49° N and 54° N showing the best performance. Populations originating from both north and south off of that region showed lower productivity, which for southern provenances resulted from their particularly low survival, reflecting the lack of adaptation to the environment of the research site. Grouping of populations based on growth traits revealed three clusters corresponding to the three latitudinal regions -northern, central and southern. Needle morphological traits were not appropriate as markers of productivity. Clustering of populations based on needle morphology, and especially based on biochemical and molecular markers, did not correspond to the grouping based on growth traits.

The provenance differences were detected for height and survival. The Sudeten populations did not differ from the non-Sudeten ones -there was a variability within both groups. The 'location × provenance' interaction was not confirmed. The initial experiment results indicate that import of fir seeds and seedlings from the locations outside the Sudetes is not recommended, while implementation of the fir restoration programme based on local resources is justified.

Recent climatic changes have resulted in an increased frequency and prolonged periods of drought and strained water resources affecting plant production. We explored the possibility of reducing irrigation in a container nursery and studied the growth responses of seedlings of four economically important forest trees: broadleaf deciduous angiosperms Fagus sylvatica L., Quercus petraea (Matt.) Liebl., and evergreen conifers Abies alba Mill. and Pinus sylvestris L. We also studied markers of water stress including modifications of biomass allocation, leaf anatomy, proline accumulation, and expression of selected genes. Growth of the broadleaved deciduous species was more sensitive to the reduced water supply than that of conifers. Remarkably, growth of the shade tolerant Abies was not affected. Adjustment of biomass allocations was strongest in P. sylvestris, with a remarkable increase in allocation to roots. In response to water deficit both deciduous species accumulated proline in leaves and produced leaves with shorter palisade cells, reduced vascular tissues, and smaller conduit diameters. These responses did not occur in conifers. Relative transcript abundance of a gene encoding the Zn-finger protein in Q. petraea and a gene encoding the pore calcium channel protein 1 in A. alba increased as water deficit increased. Our study shows major differences between functional groups in response to irrigation, with seedlings of evergreen conifers having higher tolerance than the deciduous species. This suggests that major water savings could be achieved by adjusting irrigation regime to functional group or species requirements.

Summary — The paper contains results of the preliminary stage of a provenance experiment, using the 1984 acorn crop. The acorns were harvested in pure seed stands of Quercus robur and of Q petraea and in mixed stands. In total, 36 Polish provenances were collected. Height and diameter were measured in the nursery and height in the field test. Significant differences among provenances were found for all characters. Acorn diameter was correlated with height of the seedlings in the nursery; however the correlation was not significant with height of 5-year-old plants. Quercus

In multisite forest genetic experiments, the presence of genotype × environment interaction (GEI) is common. GEI may negatively affect the estimates of genetic variance and hamper selection decisions in tree breeding programs. Several measures exist to evaluate the stability of tested genotypes’ performance across environments with a choice of the method likely affecting breeders’ decisions. In this study, we evaluated variation in diameter and height growth performance in the progeny test established at 4 sites with 80 open-pollinated half-sib families of Scots pine. We found significant variation among examined progeny at age 10, reaching up to 31% for diameter and 20% for height depending on site, and significant GEI in both traits. We estimated contribution of each family to GEI using various methods and tools of GEI analysis—AMMI, GGE biplots, heterogeneity of regression coefficients (bi’s), the deviation mean squares from regression (s2di) and Kang’s yield-stability index (YSi). Despite the presence of the cross-over interaction, family ranks did not vary much among sites. The selections based on the phenotype, YSi and restricted bi corresponded well to each other leading to the expected response to selection up to 7.8% on diameter and 4.4% on height, whereas those based on the AMMI stability variance were different and lead to a slight loss in both traits. We discuss our results in the context of the usefulness of those measures of genotype stability for tree breeding programs and propose the procedure to follow for making selection decisions in forest experiments with GEI.