Genus birch (Betula L.) leaf plates pigmentation

Abstract

A comparative assessment of various species included in the taxonomic system of the genus birch (Betula L.) by the content of pigments in the leaf apparatus was carried out. The content of pigments involved in photosynthesis was determined by spectrophotometric analysis. The concentration of pigments was estimated by the optical density of the extract from the crushed sheet plate in 96 % ethanol. It is established that the pigment composition of the leaf apparatus of various types and forms of birch is determined by genotypic and phenotypic features. The studied samples within the species showed a more restrained character in terms of the difference in pigment composition in relation to the interspecific ratio in June. However, when taking into account the same studied signs in July and August, their restraint was also observed between species and forms. The hereditary and adaptive nature of the content of photosynthetic pigments of the leaf apparatus allows us to consider this indicator as one of the identification features during the selection inventory and revision of the assortment composition of breeding and seed-growing objects. Taking into account the success of the growth of European birch on the territory of the Nizhny Novgorod region, it follows that Karelian birch is suitable for introduction into the newly created plantings, as experiments emphasize its pronounced similarity with the native species.