The influence of the geographical factor on the degree of introgressive hybridization of spruce populations in the central part of the Vologda oblast

Abstract

The identification of the influence of the geographical factor on the introgressive hybridization of spruce populations is necessary for the organization of forest seed production on a genetic-breeding basis. The paper presents the results of a comprehensive assessment of the degree of hybridization of European and Siberian spruce in the populations of the central part of the Vologda Oblast. The signs of the variability of the structure of cones proposed by I. A. Korenev (2008) were used as markers. Studies have shown the presence of significant differences in the morphometric parameters of cones in the populations of the considered part of the area, as well as in the level of their variation. Among the studied populations according to the signs of qualitative variability (the angle of sharpness of seed scales, the shape of underdeveloped scales, the shape of the lateral edge of seed scales, the type of termination of seed scales) the maximum average score determined by the method of I. A. Korenev was noted in the Vologda population. A comprehensive score assessment of the morphometric parameters of the cones revealed significant differences in the degree of hybrid between the studied populations. In general, the principal points of introgression of spruce populations within the north of the East European Plain have been confirmed. The increase in the influence of Siberian spruce is most pronounced as it moves from west to east along the line Kharovsk – Syamzha – Totma. The research results indicate that the degree of introgressive hybridization is also conditioned by the orographic factor. The degree of introgressive hybridization is influenced by the confinement of the Totma population to the banks of the Sukhona river. The article concludes that the degree of hybridization of European and Siberian spruce populations is connected with their geographical location. This factor should be taken into account when carrying out breeding work. When selecting, it is recommended to give preference to individuals of the dominant hybrid forms.