Genetic differentiation of descendants of spatially remote populations of Pinus Sylvestris L. in the conditions of provenance trials

The method of provenance trials is the one of the oldest methods of differentiation of genotypical and ecological effects in variability of traits of wood plants and assessment of prospects of of various populations use in breeding and introduction programs. However, there is a possibility of transformation of the genetic structure of the studied populations in points of tests, which can be caused, first of all, by the drift of genes and selection. Therefore, it is necessary to conduct researches on the existence of these processes in experimental populations. The objects of research are provenance trials of the Pinus sylvestris L. located in the forest-steppe zone of Western Siberia. These trials were created by planting of seedlings of 37 sources from the European part of the country, the Urals, Siberia and Kazakhstan. Western Siberia and Kazakhstan provenance were taken for the research. The study of the genetic variety of provenance trials was carried out by allozyme analysis. In the analysis 20 loci are included that code the allozyme variety of 11 enzymes (MDH, GOT, SkDH, LAP, 6-PGD, IDH, FDH, PGM, GDH, ADH, FL-EST). Statistical processing of the received results is carried out in the GenAlex 6 program. The analysis of the main parameters of genetic variability showed that the studied provenance trials of the Pinus sylvestris L. are characterized by a high level of genetic variety. The mean value of the analyzed loci polymorphism is 74%. The level of polymorphism of the natural populations from Western Siberia according to references is close to the estimates received, but varies depending on the source. The extent of genetic differentiation between the progeny of geographical populations as a whole correlates with the degree of their spatial remoteness, especially in latitude. Generally, the obtained data correspond to the picture of the interpopulation distinctions revealed in the few published works on natural pine populations in the examined and nearby territories. The main conclusion from the conducted research is that close compliance between the data on the study of allozyme variability in natural populations and similar data in provenance trials is observed. Consequently, selection and genetic drift insignificantly transform the genetic structure of experimental populations at the geographical tests that artificially concentrate the geographically isolated parts of the genofond in one territory. It can be caused by the rather small age of cultures (short period of natural selection), representativeness of selections of natural populations, and rather "neutral" nature of allozyme variability.

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