morphometry

The results of the analysis of ontogenetic and vitality structure of Сalophaca wolgarica (L. fi l.) DC. – a rare relict plant species, a paleoendemic to South-Eastern Europe – are presented. As part of the monitoring of the condition of this species’ populations, 21 natural populations on the territories of Volgograd and Rostov regions, the Republic of Kalmykia, Stavropol Krai, as well as fi ve reintroduced populations on the territory of Saratov region were studied in 2024. The ontogenetic conditions of the plants were determined.

The study of intraspecific variability of rare plants allows to estimate the level of phenotypical variability, to establish borders of populations, to characterize microevolutionary processes, to reveal the ecological factors influencing formation of structure of populations that finally promotes preservation of a gene pool of rare species. Work purpose: studying of intraspecific variability of rare species Iris pumila L. in the south of the Cis-Urals of Bashkortostan Republic.

The results of the study of biometric characteristics and aerodynamic properties of pollen of North American species: Pinus radiata D. Don, Pinus sabiniana Douglas, Pinus coulteri D. Don and autochthonous Pinus nigra subsp. pallasiana (Lamb.) Holmboe, grown on the Southern Coast of the Crimea (SCC) are presented. The differences in the size of the pollen grains and their individual parameters are revealed. The pollen of introduced species is characterized by large sizes in comparison with native species.

The article presents the results of a study of the vitality structure of four Delphinium litwinowii Sambuk coenopopulations from the Penza, Tambov and Voronezh regions in the period from 2017 to 2018. The most northern coenopopulation from Penza region in 2017 showed the strongest vitality, while the weakest was the Voronezh’ coenopopula- tion, located to the south, near the village of Vladimirovka.

The paper presents the results of studies of Oxycoccus palustris Pers. ontogenetic tactics and strategies expressed in various types of boggy phytocoenoses of the taiga zone in the Kirov region. The morphometric variability analyses of O. palustris in studied coenopopulations showed that most of parameters vary significantly. According to vitality index (IVC) the most favourable conditions are presented in mesotrophic cotton-grass sphagnum bog and oligotrophic sphagnum bog where the index was maximum – 1.04.

Preliminary results of studies on the reintroduction of Calophaca wolgarica to the territory of the Saratov region are presented. In the period from 2018 to 2020, the age structure of artificial plantings and changes in the morphological parameters of individuals within them were studied. It is shown that on the territory of the Saratov region, artificial plantings of this species are best located near the protected area “Tulip Steppe near the village of Maksyutovo”.

 The article presents the results of studying the morphological state of three populations of Delphinium pubiflorum on the basis of quantitative traits measured over four years during the period of mass flowering of plants. The greatest difference in quantitative characteristics was shown by the populations from the Krasnoarmeisky and Tatishchevsky districts of the Saratov region.