TO THE QUESTION OF MORPHOLOGY OF MYRICA GALE L. GENERATIVE PLANTS

Abstract

The distribution of Myrica gale on the coast of the Gulf of Finland is confined to regularly flooded coastal habitats, characterized by milder environmental conditions compared to the uplands and under the residual influence of the Gulf Stream. In Russia, M. gale is located on the northeastern border of the range. The study of the features of the species that contribute to the dispersal in the northern direction, and the properties of the environment that prevent such dispersal, is always of great interest. Growth in colder conditions in comparison with other members of the family, mainly inhabitants of the tropical and subtropical areas, affected the formation of such adaptations as deciduousness, changes in the structure of flowers and bark, as well as the presence of a large number of protective leaf organs. Their quantitative and qualitative analysis made it possible to establish the presence of 4 lignified parchment-like scales that do not fall completely and 6 membranous with partially lignified tops scales that stretch out while unfolding. An attempt was made for the first time to analyze the spatial structure of the shoots of the species. A sympodial growth of shoots and the phenomenon of acrotonia, as well as a spiral formation of lateral shoots, were established. In the structure of the mature generative branch of M. gale there were identified 3 types of shoots: long growth, medium and short, and also their leaf series were analyzed. Leaf series of short and medium shoots are characterized by significant asymmetry compared to leaf series of long shoots and are incomplete. The curves were constructed on the basis of such characteristics of leaf organs as their total number, length along the central vein, including the petioles (if they are presented), and internode lengths. A large number of rudiments of leaf organs determines the gradual formation of the buds, and the imperfection of the structure of the scales reflects the weak protective ability of these organs. Both features indicate the deep ancientness of the species and the difficulty in adapting to cold environmental conditions. Mature generative branches of M. gale are similar in habit to small trees, which is of particular interest in the context of modeling possible directions of adaptation during the spread of species of subtropical origin to more northern regions.