Wybór elitarnych drzew matecznych sosny zwyczajnej i modrzewia europejskiego do założenia plantacji nasiennych 1,5 generacji

Forest tree breeding is principally concerned with the improvement of growth, wood quality and vitality of tree species of economic interest. In Poland, breeding programs started in the second half of the twentieth century with the choice of plus trees to establish seed orchards. At present, seed orchards are a predominant source for the production of genetically improved seeds of conifers. In our country, Scots pine is the main forest tree, occupying almost 80% of the forest area. Annually, about 30,000 hectares of pines are artificially planted, with only a few percent of seeds coming from seed orchards. European larch is an important admixture tree species of economic significance in some areas, such as the Świętokrzyskie Mountains. Unlike Scots pine, as much as 60% of larch seeds used for artificial regeneration comes from seed orchards. There are 179 seed orchards in Poland, occupying area of 1140 ha, including 48 Scots pine and 30 European larch ones of 384 ha and 207 ha, respectively. All of them are only first generation and were established with vegetative propagules of plus trees selected in wild stands for their outstanding phenotype. Based on the results from the evaluation of plus trees in progeny trials, we selected 40 Scots pine and 40 European larch elite trees to establish 1.5−generation seed orchards. The selected trees were also characterized for their level of genetic variation with the use of nuclear microsatellite loci. We found that the examined trees have a high level of genetic variation. The mean number of alleles per locus and expected heterozygosity were 12.4 and 11.9, and 0.752 and 0.806, for Scots pine and European larch respectively. The calculated parameters are comparable to that observed in the populations of these species in Poland and other European countries. Established genetic profiles will be used in the future for controlling and monitoring the identity of elite trees in the process of creating archives of clones and seed plantations of next generation.