Lana Zorić

Heavy metal content in halophytic plants from inland and maritime saline areas

We investigated the concentration of Aluminium (Al), Cobalt (Co), Chromium (Cr), Copper (Cu), Iron (Fe), Manganese (Mn), Nickel (Ni) and Zinc (Zn) in the root and aboveground organs of four halophyte species (Salicornia europaea, Suaeda maritima, Salsola soda and Halimione portulacoides), as well as in the soil from maritime and inland saline areas. The aim of our research was to evaluate the capability of some halophyte species to absorb different heavy metals and to detect differentiation of heavy metal accumulation within populations from inland and maritime saline areas. Generally, the plant roots had significantly higher concentrations of metals when compared to stems and leaves. Zinc was the only metal with concentrations significantly higher in the leaves than in the root and stem. Populations from maritime saline areas had higher trace root and stem metal concentrations than populations from inland saline areas. Excepting zinc, populations from inland saline areas had higher heavy metal concentrations in the leaves. The factors that affected metal accumulation by halophytes included the percentage of salt in the soil. We also discuss the potential use of these halophytes in phytoremediation.

Chemical Composition of Essential Oil and Leaf Anatomy of Salvia bertolonii Vis. and Salvia pratensis L. (Sect. Plethiosphace, Lamiaceae)

The taxonomical relationship between Salvia pratensis and S. bertolonii has been unclear for a long time. Salvia bertolonii has alternatively been considered a synonym, a subspecies, a problematic subspecies and a form of Salvia pratensis. However, both these two species are sometimes used in traditional medicine instead of sage (Salvia officinalis) or as an adulteration for the same drug. In order to confirm the status of S. bertolonii, together with the potential identification characteristics for differentiation from sage, both taxa were analyzed through the analysis of their essential oils, together with the micromorphological characteristics of the leaf surface and the anatomy and morphology of the leaves. The obtained results show that there are clear differences in the quantity of essential oil (0.073% for S. pratensis and 0.0016% for S. berolonii). The major compound in the essential oil of S. pratensis was E-caryophyllene (26.4%) while in S. berolonii essential oil caryophyllene oxide was the major component (35.1%). The micromorphological differences are also pronounced in the leaf indumentum (density and distribution of certain types of non-glandular and glandular trichomes). Clear distinction between the investigated Salvia species is also observed in the leaf anatomy (in S. pratensis leaves are thinner, palisade tissue is made of 1-2 layers of cells, and leaves of S. bertolonii are characterized by 2-3 layers of palisade tissue cells, and consequently thicker).

Comparative analysis of qualitative anatomical characters of Trifolium L. (Fabaceae) and their taxonomic implications: preliminary results

A comparative anatomical study of 20 Trifolium species was carried out using light and scanning electron microscopy in order to investigate the structure of their vegetative and reproductive organs and to evaluate the taxonomic significance of qualitative characters for distinguishing between the taxa. Characters were coded and analysed by multiple correspondence analysis. The combination of selected qualitative anatomical characters of the petiole, stipules, stem, peduncle and calyx (not previously studied in detail) were significant in delimiting sections of the genus Trifolium, but not for identification of species. The characters that contributed most to the separation of sections were peduncle cross-section shape, the presence of trichomes on the calyx tubes and the presence of trichomes and crystals in the stipules.

Anatomical Characteristics of Cherry Rootstocks as Possible Preselecting Tools for Prediction of Tree Vigor

An anatomical study of roots and stems of five self-rooted cherry rootstocks with different growth control potentials was performed to compare their structure and xylem anatomy. The aim was to correlate anatomical parameters with rootstock dwarfing potential and theoretical hydraulic conductance (kh), and to evaluate the potential application of anatomical characteristics in the preselection process for prediction of ultimate tree vigor. One of the mechanisms of water transport efficiency reduction in dwarfing rootstock stems is from the rootstock xylem anatomy. Anatomical parameters of ‘Gisela 5’ and ‘Mazzard’ were typical for dwarfing and vigorous rootstocks, respectively, and were thus suggested as reference rootstocks. Significantly greater vessel diameter and frequency were found in invigorating and dwarfing rootstocks, respectively. Higher kh was obtained in roots, compared to stems, due to significantly larger vascular elements. Dwarfing rootstocks had lower kh due to small vessel lumens and percentage and, to a lesser extent, because of low wood/cortex ratios or percentage of wood. A higher percentage of wood or xylem in cherry roots and stems was not always positively correlated with their conductivity and vigor. Thus, these parameters cannot be reliably used in prediction of the ultimate vigor, although this method was previously suggested for some other fruit tree species. The most reliable anatomical parameters for that purpose proved to be vessel frequency, vessel lumen area, and percentage of vessels on wood cross section. These characteristics could thus be an effective way to estimate dwarfing capacity and could be applied in rootstock selection and breeding programs.

Anatomical characteristics and antioxidant properties of Euphorbia nicaeensis ssp. glareosa

Anatomical analyses found that leaves of Euphorbia nicaeensis ssp. glareosa are isolateral, amphistomatous, with two layers of palisade cells on the adaxial and one on the abaxial side. Laticifers are present by vascular bundles, in palisade and spongy tissue. Stem laticifers are located in the pericyclic ring, adjacent to the phloem, in cylinder parenchyma and medullar rays. The structure of pleiochasium and dichasium peduncle is similar to the stem structure. Plants from typical steppe habitat show more xeromorphic features. Phytochemical screening of extracts showed presence of catecholes, flavonoids, tannins, saponins, free quinone derivatives and absence of anthocyanins, leucoanthocyanins, alkaloids, steroid compounds and essential oils. Our results showed that the examined taxon was partially susceptible to the action of reactive oxygen species, such as O2·− and ·OH. The higher quantities of ROS thus provoked an antioxidative response from the plant, both in an enzymatic and non-enzymatic manner. Stable anatomical structure, presence and distribution of laticifers and effective antioxidant properties when exposed to ROS, make Euphorbia nicaeensis subsp. glareosa potentially interesting for further pharmaceutical and phytochemical examinations.

Morpho-anatomical differentiation of Suaeda maritima (L.) Dumort. 1827. (Chenopodiaceae) populations from inland and maritime saline area

Morphological analysis of four populations of Suaeda maritima was undertaken in order to examine the variation between populations from inland and maritime saline area, as well as between the two subspecies. Variability and significance of morpho-anatomical differentiation were examined using principal component analysis (PCA), discriminant component analysis (DCA) and cluster analysis. Plants of each population exhibited halomorphic and xeromorphic characteristics. The results of PCA and DCA showed that S. maritima subsp. prostrata and S. maritima subsp. maritima could be clearly separated based on their quantitative anatomical characteristics. Based on our analysis, climate and the amount of salt and ions in the soil, are important factors that enhance the adaptive potential of S. maritima.

MODIFIED STEREOLOGICAL METHOD FOR ANALYSIS OF COMPOUND LEAVES AND AN EXAMPLE OF ITS APPLICATION

Stereology, an interdisciplinary field that enables three-dimensional interpretation of planar sections, contains several methods for evaluation of quantitative parameters. The existing leaf sampling procedures were modified and adapted for compound, trifoliate leaves. The similar sampling method could also be applied on other types of compound leaves. Using Trifolium species as model species, we suggested the new way of application of this method in agronomy — precise determination of volume densities of indigestible lignified tissues (which determines forage digestibility), and of chlorenchyma and intercellulars (important for the photosynthesis). Comparison of the results obtained by classic anatomical analysis of leaf cross sections with the results of stereological analysis showed that both methods could be successfully applied for analysis of compact tissues (epidermis, vascular and mechanical). For the tissues that contained intercellulars (palisade and spongy), stereological method gave more precise results, as it enabled separate determination of volume density of intercellulars. A further advantage is that several leaf segments are analyzed and observed from four different angles. The obtained results opened new possibilities of application of stereological method in botanical and agricultural research, especially in prediction of digestibility and nutritional value of forages.

Anatomical characteristics and antioxidant ability of Centaurea sadleriana reveals an adaptation towards drought tolerance

The lamina, main vein and peduncle anatomical properties of Centaurea sadleriana Janka plants from two populations, were examined using light and scanning electron microscopy. The indumentum was comprised of glandular and non-glandular trichomes of two types. The leaves were amphistomatic, isolateral, with strongly developed palisade tissue. Secretory ducts were observed along the phloem or sclerenchyma of large vascular bundles. Collenchyma alternated with chlorenchyma in the main vein and peduncle. Large groups of strongly lignified sclerenchyma were present along the phloem of peduncle vascular bundles. These features, together with thickened walls of epidermal cells and cuticle, numerous trichomes and thick-walled parenchyma in the perimedullar zone, were perceived as a xeromorphic peduncle structural adaptation. Non-enzymatic antioxidant compounds of phenolic origin were detected in small amounts and their respective content was higher in leaves compared to inflorescences. Compounds of phenolic orgin showed positive correlation with total potenial of antioxidant activity indicated by the DPPH assay. Greater total quantity of polyphenols and tannins was detected in leaves of plants from Zobnatica locality, while leaves of plants from Rimski Sanac were characterized by higher content of total flavonoids and proantocyanidins. Phytochemical analysis showed that dominant secondary biomolecules in inflorescences were phenolic pigments including anthocyanins and leucoanthocyanins, and free quinones in leaves.

Micro-morphological features of achene of wild annual sunflowers

The aim of this research is to characterize wild annual sunflowers on the basis of achene micro-morphology. Plant material was grown up on an experimental field of the Institute of Field and Vegetable Crops in Novi Sad during 2015. Achene samples were hand-collected at the time of physiological maturity. Morphological measurements of achenes were performed using stereoscopic microscope Leica MZ16 with Leica DFC 320 Camera. The micro-morphological diversity of achenes was assessed using scanning electron microscopy (SEM). Obtained results indicated the presence of some quantitative and qualitative differences in achene characteristics among analyzed species, such as in their size, color, carpopodium and stylopodium shape, and distribution of trichomes on the achene surface. The carpopodium of examined species was asymmetrical at the maturity. Differences in the cuticle and wax ornamentation in different parts of the achenes, on the anticlinal walls of epidermal cells, were identified. The SEM analysis revealed the presence of non-glandular, multicellular bi-seriate trichomes (twin hairs) on the achene surface. This trichome type consisted of two elongated, parallel cells of different length. Considering the distribution of trichomes among the apical, median and basal regions of the fruit, most of the species demonstrated greater trichome density in the apical part.

The Analysis of Petiole Histological Traits Through an Evaluation of Water Deficit Tolerance of Sugar Beet Genotypes

Water stress is considered as one of the most widespread limitations to sugar beet productivity and yield stability. Since leaf is the most significantly affected organ by drought, we focused on the petiole histological features of ten sugar beet genotypes that previously showed divergent responses to lack of water in the field. The aim was to calculate volume densities of petiole different tissues and determine the histological sources of the genotypic differences in the breeding material with respect to water use efficiency. Comparative histological analysis of the petiole was performed using classic anatomical (proximal and distal segments) and stereological methods. The plants were grown in semi-controlled glasshouse conditions. The general structure of the sample variability was established by Principal component analysis, based on the correlation matrix data. This study suggests that determination of the variation in the histological characteristics of the petioles can play an important role in water management in plants. The results reveal a higher level of variability in morphometric parameters due to the fact that petiole cross-section shapes change with its maturity. Characteristics, such as (i) petiole shape, (ii) arrangement and number of vascular bundles, (iii) number and size of vessels, (iv) volume density and distribution of collenchyma, and (v) volume density of parenchyma are promising criteria that can help in the selection of more drought tolerant genotypes.