Morphometric and biochemical features of different Bunias orientalis L. genotypes in the M. M. Gryshko National Botanical Garden of the NAS of Ukraine

The search and attraction of new, unconventional or forgotten plant species with useful properties continues to be a priority in modern biological and agricultural science. In this case, the introduction of plants is an important source of culture phytocenoses enrichment [1]. It should be noted that wild and nontraditional plants can be characterized by such useful properties as medicinal, food, fodder, energy, etc. [2, 3]. Among the wide variety of phytoresources, plants of the Brassicaceae family, containing antioxidants and anticancer components, deserve special attention for economic use [4]. Representatives of the Brassicaceae family are well known and widespread as food plants [5] and promising energy crops [6]. Bunias orientalis L. can be distinguished among this large group of plants with various uses [7]. This species originates from Eastern Europe and Central Asia and slowly spreads to other parts of Europe after its introduction into culture in the 18th century [8]. Species of the genus Bunias L. exhibited antioxidant, anticholinesterase, cytotoxic activities [9, 10]. Ethanol extracts from the aboveground phytomass of B. orientalis have high antioxidant, and from the root system – antimicrobial activity [11]. Studies of flavonols from the aerial part of B. orientalis showed increase of their concentration in flowers during the flowering stage in comparison with budding one [12]. Flavonoids are present in all tissues of B. orientalis; kaempferol, quercetin, and isorhamnetin are prevailing compounds [7]. At the M. M. Gryshko National Botanical Garden B. orientalis has been studied over the past decades as a fodder and energy plant [13, 14]. UDC 582.683.2: 581.4+581.192 https://doi.org/10.21498/2518-1017.17.1.2021.228213


Introduction
The search and attraction of new, unconventional or forgotten plant species with useful properties continues to be a priority in modern biological and agricultural science. In this case, the introduction of plants is an important source of culture phytocenoses enrichment [1]. It should be noted that wild and nontraditional plants can be characterized by such useful properties as medicinal, food, fodder, energy, etc. [2,3]. Among the wide variety of phytoresources, plants of the Brassicaceae fami-ly, containing antioxidants and anticancer components, deserve special attention for economic use [4]. Representatives of the Brassicaceae family are well known and widespread as food plants [5] and promising energy crops [6]. Bunias orientalis L. can be distinguished among this large group of plants with various uses [7]. This species originates from Eastern Europe and Central Asia and slowly spreads to other parts of Europe after its introduction into culture in the 18th century [8]. Species of the genus Bunias L. exhibited antioxidant, anticholinesterase, cytotoxic activities [9,10]. Ethanol extracts from the aboveground phytomass of B. orientalis have high antioxidant, and from the root system -antimicrobial activity [11]. Studies of flavonols from the aerial part of B. orientalis showed increase of their concentration in flowers during the flowering stage in comparison with budding one [12]. Flavonoids are present in all tissues of B. orientalis; kaempferol, quercetin, and isorhamnetin are prevailing compounds [7].
At the M. M. Gryshko National Botanical Garden B. orientalis has been studied over the past decades as a fodder and energy plant [13,14].

Plant physiology
This culture is characterized by a valuable biochemical composition, but the study of the characteristics of various genotypes is still a relevant direction for further breeding work [15]. This study aims to determine the biochemical composition of the aboveground organs of different B. orientalis genotypes in the conditions of the M. M. Gryshko National Botanical Garden of the NAS of Ukraine.

Plant material
The studies were carried out in the conditions of the M. M. Gryshko National Botanical Garden of the NAS of Ukraine (NBG) during 2017-2020. We used samples of plant organs of different Bunias orientalis L. genotypes (Genotype 1-Genotype 6), created at the NBG. The genotypes created by the method of multiple individual selection from different populations of plants introduced from the natural flora of Ukraine (except for one sample -Genotype 6, which was derived from a population imported from the Czech Republic) were investigated. The indicated genotypes are characterized by excellent biological, morphological, biochemical and productive characteristics. As perennial plants, the created genotypes of B. orientalis L. vegetate in one place from 4-5 to 10-12 years, depending on their characteristics. The generative period of development in all genotypes begins in the second year of vegetation.
Plant samples were selected and analyzed at the flowering stage, as the active phase of plant development, when they acquire the highest productivity. For analysis, 25 plants were selected from different parts of the plot. Biometric measurements were performed on 10 plants in four replicates.

Study of plant morphometric parameters
The following plant morphometric parameters were measured: plant height (cm), stem diameter (mm), number of internodes, number of leaves on the shoot, leaf lamina length (cm), leaf lamina width (cm), inflorescence length (cm), inflorescence width (cm), the number of stems (pcs.).
Biochemical analyses Biochemical analyses of plants were carried out in the biochemical laboratory of the Department of Cultural Flora of the NBG. Dry matter was determined after drying plant samples at a temperature of 105 °C to constant weight. The ash content was investigated by burning samples in a muffle furnace (SNOL 7.2-1100, Termolab) at 200-500 °C [16]. After the combustion of the test sample, the ash was used to determine the content of calcium and phosphorus by titration methods. The ash was dissolved in hydrochloric acid solution to determine the total calcium content. After the usual procedure described in the method, the solution was titrated with Trilon-B with hyd roxylamine and murexide [16].
The ash was dissolved in a nitric acid solution to determine the total phosphorus content. After adding molybdic acid ammonium, potassium oxalate solution, the whole mixture was titrated with sodium hydroxide with phenolphthalein [17].
The total sugar content was determined by Bertrand's Method using Fehling's solutions. The total content of ascorbic acid was determined by Tillmans' method [18]. The determination of β-carotene was carried out in extracts of gasoline Kalosh on a Unico UV 2800 spectrophotometer [19]. Lipid content was identified using the Soxhlet extractor in petroleum ether according to Krishchenko [18] with minor changes. Caloric content of raw materials was determined on an IKA C-200 calorimeter (benzoic acid as a standard).

Statistical analysis
The obtained data are analysed using Microsoft Excel software and presented as average values and standard deviation of the mean. Correlation analysis was carried out using Pearson's coefficient. The results are summarized in Tables 1, 2

Results and discussion
The morphometric parameters of the investigated B. orientalis genotypes were studied during the flowering stage (Table 1). These measurements were carried out for the first time.
It was revealed that the plant height varied from 140.9 to 157.5 cm, the stem diameter from 11.67 to 16 Analysis of morphometric parameters revealed a very strong positive correlation between the length and width of the inflorescence (r = 0.934), stem diameter and the number of leaves (r = 0.866), stem diameter and leaf lamina width (r = 0.852), the height of plants and the inflorescences width (r = 0.820) ( Table 2).
The study of biochemical indicators of agricultural crops is a very important stage for a comprehensive assessment of plants, further research and selection of promising species, forms and varieties [15]. The study of B. orientalis samples showed that dry matter content in the aboveground phytomass ranged from 13.58 (Genotype 1) to 16.0 (Genotype 2)%, total sugar content from 5.07 (Genotype 2) to 8.86 (Genotype 1)%, lipids from 3.33 (Genotype 1) to 6.61 (Genotype 2)% depending on genotypic characteristics (Fig. 1). The acidity level ranged from 3.28 (Genotype 6) to 4.25 (Genotype 5)%. The lack of literature data on species of the genus Bunias complicates comparison. In this regard, we have compared the obtained results with the elaborated data of other representatives of Brassicaceae. The dry matter content in the samples of different Camelina sativa genotypes was 18.13-23.38%, ascorbic acid 207.23-410.23 mg/100 g, β-carotene 0.43-2.23 mg/100 g, ash 5.08-8.75%, calcium 1.008-2.633%, phosphorus 0.086-0.157%, sugars 4.76-8.12%. The energy value was 3925.71-4097.00 cal/g [20].
As a result of studies on the accumulation of biochemical compounds in B. orientalis sam-    ples a very strong positive correlation was found between carotene and calcium levels (r = 0.834) ( Table 3). A strong correlation was also found between the accumulation of ascorbic acid and tannins (r = 0.675), dry matter and lipids (r = 0.626), carotenes and phosphorus (r = 0.619). A moderate correlation is observed between the level of dry matter and tannins (r = 0.596), ascorbic acid and phosphorus (r = 0.492), lipids and calories (r = 0.489), tannins and carotene (r = 0.479), tannins and phosphorus (r = 0.442).
Taking into account the preliminary results of the correlation analysis of various genotypes, the correlation coefficient depends on the species, form, varietal characteristics and phase of plant development [26,27]. In addition, the correlation does not show a clear relationship between two parameters, but allows for a level of variability from one to the other.

Conclusions
Analysis of morphometric parameters revealed a strong positive correlation between the length and inflorescence width, stem diameter and the number of leaves, stem diameter and leaf lamina width, the height of plants and inflorescences width. It was determined that various B. orientalis genotypes are characterized by high nutrient content, in particular, ascorbic acid and β-carotene. The highest dry matter and lipid content was found in Genotype 2, sugar in Genotype 1, ascorbic acid and phosphorus in Genotype 3, β-carotene in Genotype 6, and ash in Genotype 4 and titratable acidity and calcium in Genotype 5.
Strong positive correlation between β-carotene and calcium, vitamin C and tannins, dry matter and lipids, β-carotene and phosphorus was defined. The obtained data can be used to predict and evaluate the results of introduction and breeding studies with Bunias orientalis genotypes as promising crops in Ukraine.  Note. DM -dry matter, TSC -total sugar content, AA -ascorbic acid, TC -tannin content, TAtitratable acidity, C -carotene, A -ash, Ca -calcium, P -phosphorus, LC -lipid content, EV -energy value.