Bioecological characteristics of species of the Hypericum L. genus in flora of Azerbaijan

Бюллетень науки и практики / Bulletin of Science and Practice

UDC 582.824.3: 58.009                               

We studied the research of various scientists in the study of the genus Hypericum L. and at the end of our research we relied on the system of the British scientist N. Robson, who studied the genus through anatomical, karyological and phylogenetic studies . Prominent botanist divided the Hypericum genus into 30 sections and 6 subsections according to the structure of vegetative, generative organs and translucent glands. Accordingly, we considered it expedient to place the Hypericum species distributed in the flora of Azerbaijan on these sections . In addition to the morphological features noted above, this opinion is confirmed by the results of a molecular phylogenetic analysis of herbarium specimens collected in the botanical and geographical regions of the Republic [1, 2].

In the study of the bioecology of species of this genus, their phenology plays an important role. In our research, phenological observations were conducted for 3 years, and the resulting figures are shown on average. As a result of these observations, the beginning and end of the vegetation period in St.-John’s-wort species, the appearance of the first sprout, the development of the flower group, budding, blossoming, the time of budding of each flower, as well as the stages of seed and fruit ripening were studied. Although the vast majority of species belonging to the genus Hypericum are pollinated by insects (entomophilous), self-pollination and wind pollination also occur among these species. Reproduction of the representatives of genus takes place through seeds or short roots [3].

Although the work of many scientists is devoted to the study of bioecological features of the genus Hypericum L., the bioecological features of species distributed in the flora of Azerbaijan have not been sufficiently studied. For this purpose, research was conducted on the genus of St. John’s wort collected from different botanical and geographical regions of Azerbaijan under natural conditions in 2015-2022. As a result of the research, the bioecological features of the species belonging to the genus were studied and the regularities of the distribution of the species in the high belts, their attitude to climatic factors, phenology and ecological groups were determined . The “Life Forms” systems of C. Raunkiaer and I. Serebryakov were used to determine the life forms of the species included in the genus [4].

According to their attitude to moisture and adaptation, species belonging to the genus are divided into 3 groups: xerophytes ( H. helianthemoides (Spach) N. Robson., H. asperuloides Czern. ex Turcz., H. lydium Boiss., H. linarioides Bosse, H. elongatum Ledeb., H. perforatum L., H. scabrum L., H. nummularioides Trautv., H. karjaginii Rzazade., H. theodorii Woronow, H. elegans Steph.), mesoxerophytes ( H. hirsutum L., H. formosissimum Takht., H. pseudolaeve N. Robson, H. xylosteifolium (Spach) N. Robson, H. davisii N. Robson) and mesophyte ( H. androsaemum L., H. venustum Fenzl., H. tetrapterum Fries) (Figure 1).

■ Xerophytes

1,4

Mesoxerophytes

■ Mesophyte

8,2

Figure 1. Ecological groups of species of genus Hypericum L. in relation to humidity

We gave the classification of the life forms of the species of the Hypericum genus distributed in the Republic of Azerbaijan on the basis of the division of the Danish scientist C. Raunkiaer (1934). According to this division, all species of the Hypericum L. genus distributed in the flora of Azerbaijan are hemicryptophytes (stem dries out in unfavorable conditions, the living part of the plant remains underground and remains with dried leaves until the new vegetation): H. hirsutum , H. perforatum , H. asperuloides , H. tetrapterum, H. scabrum, H. elongatum, H. nummularioides, H. helianthemoides, H. androsaemum, H. linarioides, H. theodorii, H. xylosteifolium, H. davisii and etc. [3, 5].

According to the classification of the system of life forms by I. G. Serebryakov (1964), most of the species of the Hypericum genus (with the exception of semishrub species H. asperuloides, H. androsaemum , H. xylosteifolium , H. nummularioides ) found in the flora of Azerbaijan are perennial grass plants.

According to the substrate on which they grow, species of this genus can be divided into the following bioecological groups:

• 1.    Calcipetrophytes — which spreads in a group on sandy and stony soils: H. lydium Boiss., H. formosissimum Takht., H. linarioides Bosse., H. theodorii Woronow., H. tetrapterum Fries., H. xylosteifolium (Spach) N. Robson., H. elegans Steph., H. venustum Fenzl. and so, on species belong.

• 2.    Argillophytes — plants which growing on clay substrates: H. davisii N. Robson., H. pseudolaeve N. Robson., H. karjaginii Rzazade.

• 3.    Petrophytes (Greek “petros” — stone, “phyton” — plant) — those that creep on stony substrates and in rock crevices: H. androsaemum L., H. helianthemoides (Spach) Boiss., H. scabrum L., H. nummularioides Trautv., H. elongatum Ledeb.

• 4.    Forest — steppe species: H. hirsutum L., H. perforatum L., H. asperuloides Czern. ex Turcz.

The vast majority of wild herbs common in the flora of Azerbaijan belong to the ecological group of calcipetrophytes. Species of the genus found in the flora of Azerbaijan are distributed from the lower mountain range to the high mountain range but are more common in the lower and middle mountain ranges. In order to clarify the distribution patterns of Hypericum species depending on the height gradient, we used the scheme adopted by L. I. Prilipko in 1954 in our research. There are 10 ( H. hirsutum L. , H. elegans Steph. , H. androsaemum, H. asperuloides, H. karjaginii Rzazade, H. davisii N. Robson , H. tetrapterum Fries., H. xylosteifolium (Spach) N. Robson. , H. perforatum L., H. scabrum L.) species in the lower and middle, 3 ( H. helianthemoides (Spach) Boiss., H. formosissimum Takht., H. theodorii Woronow) in middle, 4 ( H. linarioides Bosse., H. nummularioides Trautv. , H. pseudolaeve N. Robson , H. elongatum Ledeb.) in subalpine, 2 ( H. venustum Fenzl., H. lydium Boiss.) in the high mountain belt (Figure 2).

Although most species belong to both low and middle mountain ranges, some found in only one belt. According to this mountain belts were compared and the Sørensen-Czekanowski similarity coefficient was used to determine the taxonomic composition of species living in these belts:

I s = 2a / ((a + b) + (a + c))

a — total number of species, b – number of species in the first mountain range, c – number of species in other mountain ranges.

Figure 2. Distribution patterns of Hypericum species depending on the height gradient

This similarity coefficient of the lower and middle mountain belt was found to be Is=0,74%, between the lower and upper belt is Is=0,76% and between the subalpine and upper belt Is=0,86%.

Material and methods

As a research material, herbarium specimens belonging to the genus of Hypericum L. distributed in the botanical-geographical regions of Azerbaijan and collected in different ecological conditions in 2015-2022, numerous herbarium specimens stored at the Institute of Botany of the Azerbaijan National Academy of Sciences (BAK), the Berlin Botanical Garden and Museum (BGBM), as well as in various herbarium funds of the world (GBIF) were used. Stationary surveys were conducted in all available areas from low mountain belt to high mountain belt in the administrative districts on different routes in 2015-2022. The study of bioecological features of the species of this genus was carried out on the F. Babayev’s methods, the classification of life forms is implemented based on I. Serebryakov and C. Raunkiaer’s system.

Conclusion

It was determined that 19 species, 1 subspecies and 1 species diversity of the Hypericum L. genus (St. John’s wort) belonging to 7 sections are widespread in Azerbaijan.

On the basis of a new taxonomic composition with the addition of Hypericum species not shown in the “Flora of Azerbaijan” and new diagnostic signs not used before a determinant table has been drawn up for the species included in the genus.

Also, species phenology has been studied. As can be seen from the phenological observations, the vegetation of Hypericum species in natural and ecological conditions begins in April-June, the blossoming period in May-July, and the development of the fruit lasts from early August to late September.

According to the distribution patterns of species depending on altitude was determined that this species can be found from the lower mountain range to the high mountain range and an electronic map was compiled based on GPS coordinates.