Some of issues of endemic species reproductive biology of Southern Siberia Hedysarum L

The seed productivity of endemic species of the genus Hedysarum L. in southern Siberia was studied. It is established that the reproduction of these species is carried out only by seed. Flowering occurs in June, the number of flowers in the inflorescence ranges from 12.3 to 19.1. The efficiency of fruit formation (% of the set beans from the number of flowers) differs significantly: the maximum values are marked for H. austrosibiricum, H. turczaninovii and H. sangilense (90.7-74.1 %), the minimum values are marked for the rare H. minussinense, H. chaiyrakanicum, H. zundukii (35.3 47.2 %). A decrease in the number of seeds that are set compared to the number of ovules, caused by various reasons, leads to a significant decrease in the RSP compared to the PSP. The percentage of semenification in the studied species is highest in the endemics H. austrosibiricum, H. sangilense and H. turczaninovii (56.545.1 %), the minimum in the rare H. zundukii, H. minussinense and H. chaiyrakanicum (9.8-36.5 %). In the opinion of Levina R.V. [1], species reproductive biology is a boarder concept than reproductive biology and it covers not only individual organisms (plants) biology and ecology but also vegetative population regeneration processes in general. Without knowing the characteristics of a specie’s reproductive biology, it’s impossible to assess its current state and predict perspectives of its continued existence. As a component of the reproductive process, seeds production, is an important indicator of species’ viability in the specific conditions [2]. Factors related to characteristics of structure and development of reproductive organs play an important role in seeds play an important role in seeds formation. Genotype determines this characteristic [3, 4, 5]. The normal process of reproductive structures generation is disrupted under adverse conditions, which reduces plant productivity. As result of various external factors’ influences, actual seeds productivity may decrease: earth and air temperature, humidity, photoperiod and light intensity, weather conditions of a particular season, corresponding to flowering and seed development period [1, 2, 5]. Processes of pollination and fertilization run into difficulties *Corresponding author: karnaukhova-nina@rambler.ru © The Authors, published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0 (http://creativecommons.org/licenses/by/4.0/). BIO Web of Conferences 24, 00032 (2020) https://doi.org/10.1051/bioconf/20202400032 International Conferences “Plant Diversity: Status, Trends, Conservation Concept” 2020

In the opinion of Levina R.V. [1], species reproductive biology is a boarder concept than reproductive biology and it covers not only individual organisms (plants) biology and ecology but also vegetative population regeneration processes in general. Without knowing the characteristics of a specie's reproductive biology, it's impossible to assess its current state and predict perspectives of its continued existence.
As a component of the reproductive process, seeds production, is an important indicator of species' viability in the specific conditions [2]. Factors related to characteristics of structure and development of reproductive organs play an important role in seeds play an important role in seeds formation. Genotype determines this characteristic [3,4,5]. The normal process of reproductive structures generation is disrupted under adverse conditions, which reduces plant productivity. As result of various external factors' influences, actual seeds productivity may decrease: earth and air temperature, humidity, photoperiod and light intensity, weather conditions of a particular season, corresponding to flowering and seed development period [1,2,5]. Processes of pollination and fertilization run into difficulties

Materials and methods
Research was conducted in 1983-2007 with the plants in natural phytocenosis on the territory of South Siberia.
Hedysarum austrosibiricum endemic to mountains of South Siberia is encountered on the alpine and sub-alpine meadows, in moss-lichen tundra, mixed herbs dwarf arctic birches and rocky stream gravel [7]. Material was collected on H. austrosibiricum in phytocenosis of high vein system in Kuznetsky Ala Tau around Ivanovskye lakes on the height of 1500 m above sea level in the vicinity of Priiskovy village in Ordgonykidzevsky area in Khakassia and on the height of 1700-2100 m above sea level in Altai Republic.
Hedysarum sangilense -Dwells in mid-mountain vein system and undershelf of highland vein system on steppe, meadows, rocky hills, gravels, in sporadic forests of Tyva and Northern Mongolia. Material for researching of reproductive biology of endemic to Sangilen highlands collected in Erzinsky area of Tyva Republic in the middle reaches of Naryn river on height 1500 m above sea level in larch sparse forest and in tangled vegetations. Rare species with 3 (R) status endemic to island of Enisey steppes.
Hedysarum minussinense is encountered in steppes of Minusinsk, less frequently in Abakan (south of Krasnoyarsk territory). Dwells on rocky and crush stony slopes, rockslides, gramineous mixed herbs slopes, mainly on rocky patches [8]. Materials were collected in Bogdansky area of Khakassia (region of Znamenka village) and in the area of Ust-Abakan (region of Soviet Khakasia village) in the large caespitose steppe and in the two gramineous mixed herbs associations in rocky steppe, which are petrophytic variations of gramineous zonal large caespitose steppe.
Hedysarum turczaninovii endemic is encountered in steppe [7], forest-steppe vein systems on rocky, steppe slopes, in steppes of Kemerovo region, on south of Krasnoyarsk region, Irkutsk region, in Tyva Republic. Researched by us in an area of sub-taiga and forest-steppe vein systems of Khakasia vegetation: in sub-taiga vein system of vegetation of H. turczaninovii around the area of Tuym Shirynsky village in meadow sweet vetch-mixed herbs steppe (Tuym-1) and in rocky ling-gramineous-mixed herbs steppe (Tuym-2) as well as in forest-steppe vein system of vegetation around area of Kopyevo Ordgenikidze station in gramineous mixed herbs rocky steppe.
Hedysarum zundukii is a rare species (3 R), localized endemic to west coast of Baikal lake [8,9]. The bulk of its range is a territory approximately 8 km long and 0.5 km wide within an Olhinsky area of Irkutsk region [9]. Growing by single specimens in petrophytic mixed herbs steppes at steep calcium slopes and their round rocky, crushed stony plumes and on rockslides.
Conventional methods were used to research the family productivity [2,10,11,12]. The number of flowers and set beans, number of seedbuds, number of inflorescences on the plant was calculated. On the basis of these data the researchers were counting the following indicators of seeds productivity: potential seeds productivity (PSP), real seeds productivity (RSP), seminalization percentage, sufficiency of pollination coefficient. (percent of beans to the number of flowers in inflorescences).

Results and discussion
Endemic species of South Siberian Hedysarum genus are vegetatively immobile, reproduction is strictly germiniparous. All species of Hedysarum genus have very peculiar structure of bean having overstretching between separated segments, in place where ripe fruit break down, but seeds don't spill out from a bean, like in the other leguminous plants, but germinate while remaining in the oral of the bean segment in second half of the summer (July -August). In the generative condition, sweet vetch develops varying amounts of generative shoots, vary in the number of multiflorous racemes, the number of flowers and beans in inflorescences (table 1, 2). Notably, these indicators vary depending on the ontogenetical condition of specimens and growing condition of species (table 3). Note: PSP -potential seeds productivity; RSP -real seeds productivity; C. seminalization, productivity coefficient -RSP/PSP.