MULTIDIMENSIONAL ASSESSMENT OF SCOTS PINE PLUS TREES USING INDICATORS OF NEEDLE PIGMENT STRUCTURE
The existing system of mass selection of plus trees using a phenotype can be considerably improved by means of extending the list of descriptors used as selection criteria. According to some authors, the amount of pigments in pine needles depends on the tree resistance limiting environmental factors. This approach used to assess the selection results requires thorough employment of multidimensional complex analysis of biological objects. The paper is aimed at obtaining multidimensional complex analysis of Scots pine plus trees using complex indicators of needle pigment structure and defining generalized statistic proximity of the analyzed items based on this data. Clones of Scots pine plus trees were used as the object of research, generally concentrated in archives and on forest seed plantations in Nizhny Novgorod area. The content of pigment in needles was defined using traditional methods. A number of indicators were joined into one complex factor based on the correlations between them. As a result it was possible to present the reference quantity of variables used at the initial stage research (10 indicators) reduced by their number (3 main components). The latter was of great importance especially at the finishing stage when processing large generalized complexes of multidimensional units represented by 30 or even 33 indicators – independent variables. It is expected that correlation is low between these generated complex factors. The pigment contents of needles present in every plus tree under study, was very specific. It was revealed in both: the indicators of certain pigment content (a chlorophyll-a, a chlorophyll-b, carotinoids) and their relations and total values. The degree of discrepancy in their characteristics wasn’t identical that allowed to combine the groups of objects relatively close in terms of all analyzed indicators into clusters, besides there are well noticeable distinctions between the groups. The stability of tendencies in formation of independent factors in groups of variables representing numerous characteristics of pigment contents of needles by the method of principal components was obtained. The factorial analysis allowed to reduce a number of indicators while conserving data informational content presented in the source complex. Cluster analysis allowed to group plus trees by the similarity of pigment contents in needles. The groups of plus trees having rather close characteristics in all the analyzed indicators i.e. contents of various forms of chlorophyll and carotinoids, their total contents and a ratio between them. The objects that are mostly different from the population under study were identified. Estimates of relative proximity for plus trees, defined by their belonging to common or different clusters and the place in their structure, make it possible to make a well grounded choice when selecting parental combination and diallel complexes when crossing both based on maximum similarity as well as maximum difference between objects.