Based on light microscopy investigation of fruits and seeds in Gladiolus imbricatus and Iris sibiriса, new data on morphogenesis and histogenesis of the pericarp and seed coat development have been revealed. The inner ovary structure, vascular system and fruit dehiscence were also studied. The ovary of the studied species has trilocular basal part and unilocular upper part with incomplete septae. The vascular system in both species is composed of three dorsal veins and three septal veins. The dorsal veins are each divided into three vascular bundles radially whereas the septal veins are also each divided into three bundles but tangentially. Vascular supply of ovules is provided by septal veins in the central column. In both species, the floral tube falls down with adnate stamens and style at the beginning of fruit ripening. For both species, a dorsiventral (valvate) type of fruit dehiscence is characteristic; however, in I. sibiriса, a dorsal (fissuricidal) type, in which valvae are connected at the center, top and base of the capsule, occurs as well. According to our data, capsule in both species belongs to the Lilium-type, with lignified endocarpium. In G. imbricatus, we observed early tissues differentiation in the pericarp as well as earlier and faster dorsal slits formation. The seed coat in G. imbricаtus is of endotestal type, while in I. sibirica-of exotestal type. Highly specialized features of the seed coat in G. imbricatus are the following: wing formation by outer integument, few-layered mesotesta and destruction of cellular structure of the inner integument. The obtained data complement our previously suggested consideration about more pronounced morphological adaptations for dissemination of fruits and seeds in G. imbricatus. In this article, we confirm the high level of adaptiveness of fruits and seeds in the anatomy and histogenesis of the pericarp and seed coat in G. imbricatus to external conditions.

The highest parts of the European mountain massifs are covered by subalpine and alpine vegetation, with rich flora containing many relic woody plants adapted to cold temperatures and relatively short vegetation periods. In the Ukrainian Carpathians, only several highest mountain massifs form environmental conditions suitable for high mountain plants. The aim of the study was the detection of the centre of biodiversity of the high mountain plants in the East Carpathians in Ukraine. We expected the largest number of high mountain woody species in the Ukrainian East Carpathians would occur in the Chornohora, the largest and most elevated mountain chain in the country. To solve this problem, the geographic distribution of 16 woody species was analysed cartographically. We gathered georeferenced data of 919 localities of taxa, which occur in the subalpine and alpine vegetation belts, and prepared maps of their distribution using QGIS software. Additionally, we analysed vertical distribution and occurrence on different expositions of every taxon. Most of analysed subalpine and alpine species occur in the highest and the largest mountain massifs. The high mountain woody species occur in the Ukrainian parts of the East Carpathians mainly in the largest mountain massifs, the Chornohora, Svydovets, Chyvchyny, Marmarosh, and to a lesser extent, also in the Gorgany. The vertical distribution and predominant occurrence on the northern or close to northern expositions of most subalpine and alpine species indicate their demands for the relatively high level of humidity of the soil and high level of precipitation. These condition point to the relic character of most of analysed species, which origin from the glacial periods of the Pleistocene. Most of the taxa, which have centres of their distribution in the alpine and sub-alpine vegetation belts of the East Carpathians in the Ukraine territory are valuable but threatened elements of the Ukrainian flora.

Results of a study of self-pollination in two of Ukrainian flora's threatened species, Gladiolus imbricatus and Iris sibirica (Iridaceae), are presented. To confirm or refute the occurrence of self-pollination in G. imbricatus and I. sibirica, an experiment was conducted on pollen germination on their stigmas. It has been found that in G. imbricatus pollination with autogenous pollen grains on the last day of flowering leads to the growth of pollen tubes in the cases of both hand and natural pollination. However, pollen grains on the stigma of an isolated I. sibirica flower were not detected on the first or last day of flowering, which means the absence of a mechanism of autonomous pollen transfer within the meranthium. Ungerminated pollen grains were also found on the stigma after autogenous hand pollination. It has been experimentally confirmed that in the absence of pollinators at the end of the flowering phase in G. imbricatus, as well as in some other members of the genus, self-pollination and self-fertilization are possible, which contribute to the wellbeing of populations and species. With regard to I. sibirica, it has been found that the autogamous self-incompatibility inherent in this species prevents inbreeding, maintaining heterozygosity in plant populations, allowing plants' better adaptation to different environmental conditions.