GENOTYPIC DIFFERENCE OF PLUS TREES OF SCOTS PINE (PINUS SYLVESTRIS L.) BY PHYSIOLOGICAL STATE OF SHOOTS

Abstract

Introduction. Development of Russian forest seedage on the genetic-selection basis is supposed to improve the existing system of plus trees selection by increase of a number of assessed characteristics, used as the selective criteria and markers, and enlargement of the methods of an extensive analysis. The goal of the research was to make a comparative assessment of plus trees of Scots pine by a number of characteristics of physiological condition of plants and to define the selective significance based on the assessment. Research techniques covered the comparison of physiological condition of the analyzed plants by presence of fats and starch in the tissue of the studied plants, as well as by lignification of the cells of xylem. The traditional methods of histochemical analysis with the definition of relative marks using the offered scale (the authors offered the abovementioned scale) were used. According to the research results, plus trees have a significant difference by their physiological condition. One-factor and two-factor dispersion analysis proved its genotypic dependence. The share of dispersion, connected with the differences between the ortets was 16,79±8,11 % - 63,56±3,55 %. The obtained data determined the possibility to include the list of characteristics into the feature complex when multidimentional classification of the objects of forest selection. The extent of the genotypic dependence of the specified difference of plus trees was defined by the overall performance – nonidentity index. This criterion made it possible to range all the assortment by the growth of values and make the groups of plus trees by their genotypic individuality. Five of forty objects were defined to belong to the category with high index valuation (0,50 – 0,74(9)). Plus trees with higher figures of the nonidentity index have less coincidences in all the complex of characteristics. It shows less probability of their genetic affinity and less danger of negative consequences occurrence of inbreeding depression of the trees grown out from the seeds on cross breeding with other plus trees. They are more preferable in composition of the first-order seed plantations and the seed plantations with the genetic value of higher value. Conclusion. The extent of difference of values when comparison of the analyzed characteristics of plus trees is explained by their individual peculiarities and determined by their genotypic characteristics. Multivariable discrepancy of plus trees allows to make an integral estimation of their genotypic difference which assures definition in their composition of the assortment of seedage plantation and clones storage of the preferable trees as the object of constant seed base.