Assimilation apparatus of evergreen vines in humid subtropics of Russia

Abstract

In the article, the research results on the morphophysiological parameters of the assimilation apparatus of evergreen vines in the humid subtropics of Russia are presented. Тhe endemic species to subtropical regions of East Asia, including Trachelospermum asiaticum (Siebold & Zucc.) Nakai, Trachelospermum jasminoides (Lindl.) Lem., Trachelospermum liukiuense Hatus., Clematis armandii Franch., Kadsura japonica (L.) Dunal and Akebia quinata (Houtt.) Decne. were studied. Morphological traits (the area and thickness of the leaf blade), physiological traits (the content of dry substances and the main photosynthetic pigments in the leaves) and the integral parameter (the specific surface density of the leaf) were studied in dynamics by standard methods in plant physiology. It was established that evergreen vines exhibit specific and seasonal differences in the dynamics of morphophysiological parameters of the assimilation apparatus, while the variation in these parameters directly depends on the hydrothermal conditions of cultivation. Such morphological traits as the area and thickness of the leaf blade depend on the temperature and relative humidity of the air, respectively, while physiological and such integral parameters as the specific surface density of the leaf depend on the relative humidity of the air. Тhe dynamic changes in a number of morphophysiological properties of plants underlying the adaptability of exotic species along with correlative relationships between abiotic stress factors and the physiological state of plants allow a group of promising evergreen vines for ornamental gardening in a humid subtropical climate to be defined. Here, among the representatives of the genus Trachelospermum , T. asiaticum exhibits great adaptive potential. In landscaping of the coast, however, the less stable species T. jasminoides is are widely found. Less common in landscape construction C. armandii, A. quinata and uncommon in the region K. japonica must be placed factoring in the microclimatic characteristics of the landscaping object and the environmental requirements for the vines.