Population status and variation of the rare species Dactylorhiza viridis (L.) R. M. Bateman, Pridgeon & M. W. Chase (Orchidaceae) under anthropogenic load conditions in the meadow phytocenoses of the Central Caucasus

We studied the variation of morphological characters, ontogenetic structure and vitality of seven cenopopulations of Dactylorhiza viridis (L.) R. M. Bateman, Pridgeon & M. W. Chase within the Kabardino-Balkar Republic in 2015–2019. The studies were conducted in the meadow plant communities under different conditions of anthropogenic load (recreation and grazing). The species presents medium phytocenotic plasticity of morphological characters (I p=36–70%) and high variation of morphological characters (CVх–ср=18,55–45,22%) under changeable conditions of growth.

The Influence of Ecological Factors on Variability of Morphometric Parameters of Rare Species Iris pumila L.

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.

Ecological and Phytocenological Characteristics of Associations of Delphinium Pubiflorum

 posed to any significant anthropogenic impact due to the sufficient remoteness and inaccessibility of habitats. The area occupied by the associations does not exceed 400 m2. The total projective cover amounts to 90–100 %. The associations are quite rich and relatively even in terms of species composition. The number of species ranges from 48 to 72, and the most homogeneous association is the one in Krasnoarmeysky raion which also occupies the smallest territory. The number of species registered in one and the same association varies from one year to the next.

Pollen Grain Size Polymorphism in Late Tulip (Tulipa gesneriana L., 1753) Cenopopulations within the Territory of “Ivanovo Field” Natural Boundary

One of the large populations of the late tulip (Tulipa gesneriana L., 1753) grows in Fedorovsky district of the Saratov region on the territory of the regional “Ivanovo field” natural boundary where it is presented by three cenopopulations. The work is aimed at studying of mature pollen morphology of the given cenopopulation plants characterised by various variants of flower parts coloration. We analysed the dimension and other morphological features of the pollen fixed in 2012 when rich diversity of floral envelope coloration was registrated in the research area.

The State of the Cenopopulation Delphinium Pubiflorum (Dc.) Turcz. Ex Huth in Tatishevskiy District of the Saratov Region

Delphinium pubiflorum grows sparsely in the meadow-steppe forbgrass-shrub community on carbonate chernozem fairly rich soil. Habitat conditions correspond to moderately variable meadow-steppe hydration. The spatial structure of populations of non-uniform: there are a multitude of plants and detached instances; population density was approximately 7–8 plants per 100 m2.

The Variability of Some Morphological Parameters Calophaca Wolgarica in the Populations of the Volgograd Region

It is shown that habitat conditions have a strong influence on the shape and vitality of the state of the individual Calophaca wolgarica. The most favorable conditions for the growth of Calophaca wolgarica in the Volgograd region are aligned sites with non-light-chestnut fairly rich soils in shrub-grass and couch-grass communities on the edges of the belts, on which there is no mowing and minimal grazing.