Aerial Parts Of Plant Research Articles

Dose-Dependent Potential of Chitosan to Increase Yield or Bioactive Compound Content in Tomatoes

Chitosan is a natural polymer with multiple applications in agriculture due to its ability to stimulate plant growth and resistance to both biotic and abiotic stressors. The impact of chitosan application on fruit production and quality was studied under greenhouse conditions in a summer crop in a semi-arid climate. Treatments consisted of the spray application of this biostimulant to the aerial plant part at different doses (0, 0.1, and 1 g L−1). Treatment with the lowest dose did not produce significant differences in yield (total production, number, and mean weight of the fruit), but increased the concentration of flavanones (trusses 2 and 7) and phloretin-C-diglucoside (truss 2) with regard to the control. On the contrary, the high-dose treatment increased the yield due to the rise in the number of fruits and produced a significant decrease in the concentration of vitamin C, lutein, β-carotene, and hydroxycinnamic acids (trusses 2 and 7); lycopene, phytoene, and phytofluene in truss 2; and flavanols and phloretin-C-diglucoside in truss 7. These results show the ability of chitosan to improve tomato yield or to enhance the accumulation of bioactive compounds (phenolic compounds) in fruit, depending on the dose. Results are explained on the basis of the ability of chitosan to activate yield and secondary metabolite production, the dilution effect due to an increased fruit load, and the interaction of chitosan with changing environmental factors throughout the crop cycle.

Hexavalent chromium-reducing plant growth-promoting rhizobacteria are utilized to bio-fortify trivalent chromium in fenugreek by promoting plant development and decreasing the toxicity of hexavalent chromium in the soil

BackgroundFenugreek is known to have good anti-diabetes properties. Moreover, several studies accounted that the trivalent form of chromium [Cr(III)] also have anti-diabetic properties. However, its hexavalent form i.e., Cr(VI) is known to be highly toxic and carcinogenic to living beings and retarded plant growth even if it is present in low concentration in soil. Many plant growth-promoting rhizobacteria (PGPR) are reported to have the potential to reduce the Cr(VI) into Cr(III) in soil. In view of the above, the present objective was designed to effectively utilize Cr(VI) reducing PGPRs for the growth and development of fenugreek plant in Cr(VI) amended soil, apart from reducing Cr(VI) in soil and fortification of Cr(III) in the aerial part of plants. MethodsThe experiment was carried out to evaluate the effect of Cr(VI)-reducing PGPRs viz. Bacillus cereus (SUCR44); Microbacterium sp. (SUCR140); Bacillus thuringiensis (SUCR186) and B. subtilis (SUCR188) on growth, uptake and translocation of Cr as well as other physiological parameters in fenugreek grown under artificially Cr(VI) amended soil (100 mg kg−1 of Cr(VI) in soil). ResultsThe aforementioned concentration of Cr(VI) in soil cause severe reduction in root length (41 %), plant height (43 %), dry root (38 %) and herb biomass (48 %), when compared with control negative (CN; uninoculated plant not grown in Cr(VI) contaminated soil). However, the presence of Microbacterium sp.˗SURC140 (MB) mitigates the Cr toxicity resulting in improved root length (92 %), plant height (86 %), dry root (74 %) and herb biomass (99 %) as compared with control positive (CP; uninoculated plants grown in Cr(VI) contaminated soil). The maximum reduction in bioavailability (82 %) of Cr(VI) in soil and its uptake (50 %) by the plant were also observed in MB-treated plants. However, All Cr(VI)-reducing PGPRs failed to decrease the translocation of Cr to the aerial parts. Moreover, the plant treated with MB observed diminution in relative water content (13 %), electrolyte leakage (16%) and lipid peroxidation (38 %) as well as higher chlorophyll (37 %) carotenoids (17 %) contents and antioxidants (18%) potential. ConclusionThis study demonstrates that MB can lower the Cr(VI) toxicity to the plant by reducing the bioavailable Cr(VI), consequently reducing the Cr(VI) toxicity level in soil and helping in improving the growth and yield of fenugreek. Additionally, Cr(III) uptakes and translocation may improve the effectiveness of fenugreek in treating diabetes.

Quantitative Determination of Metabolites of Turkestan Soaproot (Allochrusa gypsophiloides (Regel) Schischk.) Grown in Kazakhstan

Allochrusa gypsophiloides (Regel) Schischk. (Caryophyllaceae Juss.), Turkestan soaproot (TSR) is a super producer of triterpene saponins with a wide spectrum of pharmacological activity and high surface-active properties. The realization of his full commercial potential requires biochemical studies with a focus on the metabolites dynamics at various phases of plant development and in connection with the storage duration of raw plant material. Spectrophotometric determination of saponins in terms of oleanolic acid was carried out in roots with different morphometric parameters and the aerial part from wild plants collected in the south of Kazakhstan. The content of saponins, carbohydrates, phenols, and flavonoids as well as the foaming properties of ethanol extracts obtained from air-dried TSR roots before and after their long-term storage were evaluated. The maximum quantity of saponins was revealed in average roots from middle-aged and mature generative plants in fruiting. A high level of saponins was detected in the aerial part of plants during the flowering, which decreased twice at the fruiting stage. After long-term storage of the roots, an increase in the initial content of saponins and flavonoids combined with a decrease in carbohydrates was noted. Saponins accumulation was confirmed by a 12-fold increase in the foaming index in the aqueous extract from the deposited roots relative to its initial value in the extract from the original roots. The data obtained indicate the possibility of alternative use of the aerial part of the original plants of A. gypsophiloides at the flowering stage to obtain triterpene saponins.

Evaluation of the Agronomic Efficiency of Azospirillum brasilense Strains Ab-V5 and Ab-V6 in Flood-Irrigated Rice

The rational use of nitrogen fertilization is fundamental, not only to increase recovery efficiency, but also to increase crop productivity and reduce the production costs and risks of environmental impacts. In the State of Rio Grande do Sul in Brazil, irrigated rice productivity can surpass 8 tonne·ha−1 as a result of the technification of the crop and favorable environmental conditions, yet there is great variability in the agronomic efficiency of chemical nitrogen fertilizers, which rarely exceed 50% of the applied dose. Biological nitrogen fixation is one of the technological alternatives for reducing the use of nitrogen in this crop. In this study, the agronomic efficiency of Azospirillum brasilense strains Ab-V5 and Ab-V6 in terms of biological nitrogen fixation in flood-irrigated rice cultivars in a lowland agroecosystem was evaluated through five field experiments. A. brasilense combined with reduced nitrogen fertilization (reduction of 30 kg N·ha−1) increased the dry mass of the aerial part of rice plants by 3.2%, and promoted an increase in N concentration in stems and leaves and in the N content exported by grains by 43% and 27.5%, respectively, in relation to the absence of N and inoculant, and promoted an average increase of 30% in rice production.

Hepatoprotective potential of isolated flavonoids from Trapa natans L. against the paracetamol induced oxidative stress in rats

Overdose of paracetamol causes liver toxicity, due to oxidative stress by the reactive oxygen species (ROS) that increases the levels of ALT and AST, and reduces the level of the antioxidant enzymes. Flavonoids are a source of natural antioxidants that assist in neutralization of ROS. Several studies have suggested that flavonoids can help protect the liver. The Water Chestnut, Trapa natans L. plants have long been used in the traditional system of medicine and possess considerable antioxidant potential. In this study, we tried to isolate flavonoids from T. natans L. and evaluate the hepatoprotective potential of the isolated compound. We isolated flavonoids from the extract of the aerial part of plant and characterized by UV, IR, NMR and Mass spectroscopy. The isolated flavonoid was induced orally once a day (30 mg/kg). The test drug (isolated compound) could lower the elevated levels of serum enzymes such as glutamate oxaloacetate transaminase (AST), serum glutamate pyruvate transaminase (ALT), alkaline phosphatase (ALP) and total bilirubin. Silymarin (30 mg/kg) was taken as a standard drug that exhibits significant hepatoprotective activity against the paracetamol induced hepatotoxicity model in Wistar albino rats. The histopathological study of rat liver also strengthens biochemical evaluation analysis. Based on the experimental results, it can be concluded that the isolated flavonoids act as hepatoprotective agents in rats.

Effects of fluoride pollution on the development of the Mediterranean plant species Atractylis serratuloides Sieber ex Cass. (Asteraceae)

Exploring fluoride impacts on species' survival strategies and predicting later pollution effects on community structure is a key question in ecological studies. To address this issue, a field study was conducted during two seasons on fluoride-contaminated soil in southern Tunisia. Gabes was the most polluted site, with almost 1600 ppm. Smara was the reference site, with almost 56 ppm. F accumulations were above the usual background concentrations. Fluorine (F) concentrations in the plant aerial part of Atractilys serratuloides, an arid gypsum-tolerant plant species that is abundant in the surroundings of superphosphate factories in Tunisia, reached around 300 ppm in Gabes. Simultaneously, plant seasonal development (life cycle) monitoring was also carried out to assess the shoot vegetative growth and phenological stages of Atractilys serratuloides under fluoride pollution. Earlier reproduction events (flowering and fructification) were detected at the expense of reduced shoot vegetative growth of this species in both polluted sites, especially in the summer season. This strategy may enhance A. serratuloides’ earlier achievement of its reproduction stage and thus fosters its chance of colonizing the F-enriched soils in the factories’ surroundings.

ПРИМЕНЕНИЕ МЕТОДА ЯМР C ПАРАМАГНИТНЫМ ДОПИНГОМ ДЛЯ ОЦЕНКИ АПОПЛАСТНОГО ПЕРЕНОСА ВОДЫ В КОРНЯХ ИНТАКТНЫХ РАСТЕНИЙ ПРИ ДЕЙСТВИИ АБИОТИЧЕСКИХ СТРЕССОВ

In this work, the methodological approach based on low-field NMR using the GdDTPA paramagnetic complex for the qualitative assessment of water transport along the apoplastic (extracellular) pathway in the roots of intact wheat plants is proposed. This approach consists in measuring the spin-spin relaxation times of the water magnetization in the roots during simultaneous incubation of the roots in a solution of the paramagnetic Gd-DTPA complex and the impact of a stress factor on the plants. During root incubation, this complex spreads only along the root apoplast system and shortens the apoplast water relaxation times. GdDTPA does not penetrate into the cells and, accordingly, does not change the intracellular water relaxation times. Thus, the rate of decrease in the relaxation times of the magnetization of apoplast water, which directly depends on the intensity of water transfer through the apoplast, can be used to determine the relative contribution of water transfer through the root apoplast during stress exposure. A twofold increase in the concentration of carbon dioxide in the aerial parts of plants was used as an abiotic factor presumably influencing the transfer of water along the root apoplast. Using this methodological approach, it was shown that increase in the CO2 concentration in the leaf zone of wheat plants to 800 ppm leads to decrease in the rate of water transfer through the root apoplast by 2–2.5 times compared with the control at ambient CO2 concentration of 400 ppm.

Physiological responses of the beet crop under agricultural environment and saline stress

The deleterious effects of salts on plants exposed to high solar radiation tend to be more accelerated due to the increase of toxic ions in the aerial plant part. Consequently, the physiological and biochemical processes will be affected. These effects can be minimized, however, with the use of management strategies, such as the use of a shading screen and a protected environment. In this sense, the objective of this work was to evaluate the physiological responses of sugar beet cultivated in different environments and irrigated with saline water. The experiment was conducted in an experimental design entirely randomized, using the factorial scheme 3 × 2, equivalent to three environments (FS = full sun; SSOS = shading screen open on the sides and PE = protected environment) and two electrical conductivities of the irrigation water (0.5 and 6.2 dS m-1), with four repetitions. At 45 days after sowing (DAS) the following variables were analyzed: stomatal conductance, liquid photosynthesis, transpiration, internal CO2 concentration, leaf temperature, instantaneous water use efficiency, instantaneous carboxylation efficiency, intrinsic water use efficiency, and relative chlorophyll index. Irrigation with water of higher salinity negatively affected stomatal conductance, net photosynthesis, leaf temperature and instantaneous water use efficiency of sugar beet plants grown in a full sun environment. The protected environment and open shading on the sides partially mitigated the deleterious effects of salinity.
 Keywords: Beta vulgaris L., gas exchange, salinity levels.

Ecology and functional potential of phyllosphere yeasts.

The phyllosphere (i.e., the aerial parts of plants) harbors a rich microbial life, including bacteria, fungi, viruses, and yeasts. Current knowledge of yeasts stems primarily from industrial and medical research on Saccharomyces cerevisiae and Candida albicans, both of which can be found on plant tissues. For most other yeasts found in the phyllosphere, little is known about their ecology and functions. Here, we explore the diversity, dynamics, interactions, and genomics of yeasts associated with plant leaves and how tools and approaches developed for model yeasts can be adopted to disentangle the ecology and natural functions of phyllosphere yeasts. A first genomic survey exemplifies that we have only scratched the surface of the largely unexplored functional potential of phyllosphere yeasts.

Electro-enhanced phytoremediation system on the removal of trace metal concentration from contaminated water

The combination of electro-enhanced and hydroponic phytoremediation hereinafter referred to as electro-enhanced phytoremediation (EP) system, has been employed for rapid removal of trace metal concentration of lead (II) from contaminated water using Kentucky bluegrass (Poa pratensis L.) as accumulator plant. In this study, for rapid assessment the effectiveness of two-dimensional (2D) electrode configuration in electro-enhanced system was evaluated by agar media for 48h period of time. Furthermore, these configurations were applied to enhance the EP system for 9d period of time. Also, a common agrochemical-urea as chaotropic agent to facilitate the healthy growth of plant in contaminated water was evaluated. The results showed that the accumulation of lead (II) concentration was higher in the plant roots (i.e. high bioaccumulation coefficient (BC) value) than in aerial parts of plant (i.e. low translocation factor (TF) value). Also, the accumulation of lead (II) concentration in plant was higher under the treated urea of EP system. The chlorophyll content, biomass accumulation productivity, and water content (i.e. dry weight-fresh weight (DW/FW) ratio) of plant either under the treated urea or untreated urea with high accumulation of lead (II) concentration revealed that the Kentucky bluegrass has able to hold out the plant stress.

HPTLC quantification, assessment of antioxidant potential and in vivo hypoglycemic activity of Scorzonera latifolia (Fisch. & C.A. Mey.) DC. and its major compounds

Scorzonera L. (Asteraceae) species have long been the topic of many phytochemical, analytical, and biological studies since various species of the Scorzonera genus have been widely used as food and medicinal purposes. Apart from its traditional use to relieve pain, promote wound healing, treat helminth infections or women infertility, Scorzonera latifolia (Fisch. & Mey.) DC is also used for its antidiabetic activity. We aimed to investigate antidiabetic activity of the aerial parts of the title plant and its major secondary metabolites (hyperoside, isoquercitrin, 7- O -methylisoorientin, isoorientin, swertisin, chlorogenic acid, 4,5- O -dicaffeoylquinic acid and hydrangenol-8- O - β -glucoside) isolated from aerial parts in alloxan-induced diabetic mice. Blood glucose levels were measured four times: before the treatment, after 1 st , 2 nd , and 4 th hours of sample treatments (100 mg/kg i.p.). S. latifolia extract displayed notable decline after 4 hours of administration. Among the metabolites; swertisin, 7- O -methyl-isoorientin, and hydrangenol-8- O - β -glucoside were associated with significant reduction on blood glucose level of alloxan-induced diabetic mice. Due to the strong relationship between oxidative stress and diabetes, antioxidant activity of S. latifolia was additionally tested. Furthermore, 4,5- O -dicaffeoylquinic acid, chlorogenic acid, hyperoside, and swertisin contents as major components of the extract were quantified by HPTLC-densitometry, as their biological effects can be attributed to their phenolic contents.

Effects of Extraction Solvents on the Total Phenolic Content, Total Flavonoid Content, and Antioxidant Activity in the Aerial Part of Root Vegetables

The present study aimed to investigate the total phenolics, total flavonoids, and antioxidant activity in terms of the DPPH scavenging, reducing power, and H2O2 scavenging of the aerial parts of onion, white radish, red radish, carrot, and beet as affected by different extraction solvents. Generally, the aerial part of these vegetables has high antioxidant properties. Samples were extracted with methanol (100 and 70%), ethanol (100 and 70%), and water. Total phenolic content was highest when the samples were extracted using 100% methanol, while extraction with 100% ethanol yielded the highest total flavonoids. The highest DPPH activity and H2O2 scavenging values were obtained by extraction of the aerial plant parts with 70% ethanol, and the 70% methanol extract had the highest reducing power. Partial least regression (PLS) was performed to validate the optimum solvent for extraction of the antioxidants and their activity in each plant. The PLS indicated that there was a variation in the validation of the different extracts for each plant. The high antioxidant capacity of root vegetables, which is natural, indicates that they may have health and dietetic advantages for consumers.

Sites of biosynthesis, distribution and phloem transport of 3-isobutyl-2-Methoxypyrazine in Capsicum annuum (bell pepper) plants

The distribution and translocation as well as the biosynthetic sites of 3-isobutyl-2-methoxypyrazine (IBMP) in bell pepper plants (Capsicum annuum) were examined. For IBMP-quantification, a stable-isotope dilution assay (SIDA) was developed, using headspace solid-phase microextraction (HS-SPME) combined with gas chromatography and time-of-flight mass spectrometry (ToF-MS). While IBMP was the most abundant MP in all aerial plant parts, IPMP was dominating in root tissues. The highest IBMP-levels were found in unripe bell pepper fruits. Moreover, feeding experiments with [2H10]-l-leucine revealed that IBMP is biosynthesized in all plant parts, while in roots and ripe bell pepper fruit tissues no incorporation of the labelled precursor was detectable. A potential phloem translocation of IBMP could not be detected.

Bioremediation of crude oil and its effect of residue in growth of wheat plants

Three strains of bacteria were studied to bioremediation crude oil in soil and in the laboratory. These bacteria were Azospirillum spp., Azotobacter spp. And Rhizobium spp. The results showed that Azospirillum spp. , Rhizobium spp. was more efficiency to bioremediation crude oil than Azotobacter spp., also the results showed that the higher number of bacteria was recorded in soil treatment with Rhizobium spp. in presence of crude oil in first week , and the number of this bacteria reached to 22.6 x 108 , but the lowest number of bacteria was recorded in soil without added crude oil (control), and the number reached to 2 x 107.The statistical methods obtained that no significant were recorded between different treatments . Also, the results showed that the numbers of bacteria in soil treatment with crude oil were decreased regularly from second week until ten weeks. The results showed that the height of the aerial parts of wheat plants reached to 73 cm in soil treatment with Azotobacter spp. And crude oil after 10 weeks, and the lower length reached to 47 cm. At the same time the results obtained that the higher wet weight of wheat plants was reached to 56 gm in soil treatment with Rhizobium spp., and in the presence of crude oil after 10 weeks, but the lower wet weight was reached to 25 gm in control. Also, the results showed that the higher of dry weight of wheat plants was reached to 23 gm in soil treatment with Rhizobium spp. and in the presence of crude oil after 10 weeks, but the lower dry weight was reached to 10 gm in control, however the statistical methods that no significant were recorded between the different treatments. Also, that all these bacteria have ability to removal crude oil in soil and in mineral salts medium.

Spatial and Temporal Variability and Driving Factors of Carbon Dioxide and Nitrous Oxide Fluxes in Alpine Wetland Ecosystems.

Plants regulate greenhouse gas (GHG) fluxes in wetland ecosystems, but the mechanisms of plant removal and plant species that contribute to GHG emissions remain unclear. In this study, the fluxes of carbon dioxide (CO2) and nitrous oxide (N2O) were measured using the static chamber method from an island forest dominated by two different species, namely Betula platyphylla (BP) and Larix gmelinii (LG), in a marsh wetland in the Great Xing'an Mountains. Four sub-plots were established in this study: (1) bare soil after removing vegetation under BP (SBP); (2) bare soil after removing vegetation under LG (SLG); (3) soil with vegetation under BP (VSBP); and (4) soil with vegetation under LG (VSLG). Additionally, the contributions of the dark respiration from plant aerial parts under BP (VBP) and LG (VLG) to GHG fluxes were calculated. We found that the substantial spatial variability of CO2 fluxes ranged from -25.32 ± 15.45 to 187.20 ± 74.76 mg m-2 h-1 during the study period. The CO2 fluxes decreased in the order of SBP > VSLG > VSBP > SLG > VLG > VBP, indicating that vegetation species had a great impact on CO2 emissions. Particularly, the absence of vegetation promoted CO2 emission in both BP and LG. Additionally, CO2 fluxes showed dramatically seasonal variations, with high CO2 fluxes in late spring (May) and summer (June, July, and August), but low fluxes in late summer (August) and early autumn (September). Soil temperatures at 0-20 cm depth were better predictors of CO2 fluxes than deeper soil temperatures. N2O fluxes were varied in different treatments with the highest N2O fluxes in SLG and the lowest N2O fluxes in VBP. Meanwhile, no significant correlation was found between N2O fluxes and air or soil temperatures. Temporally, negative N2O fluxes were observed from June to October, indicating that soil N2O fluxes were reduced and emitted as N2, which was the terminal step of the microbial denitrification process. Most of the study sites were CO2 sources during the warm season and CO2 sinks in the cold season. Thus, soil temperature plays an important role in CO2 fluxes. We also found that the CO2 flux was positively related to pH in a 10 cm soil layer and positively related to moisture content (MC) in a 50 cm soil layer in VSBP and VSLG. However, the CO2 flux was negatively related to pH in a 30 cm soil layer in SBP and SLG. Our findings highlight the effects of vegetation removal on GHG fluxes, and aid in the scientific management of wetland plants.

Growth responses of tomato plants (Solanum lycopersicum) to aluminium and nickel from nanoparticle suspensions and ionic solutions

ABSTRACT We have recently described the fate of gamma-alumina-based nanomaterials containing Ni and non-nanometric Ni on soil from lysimeters. The objectives of the present work were to evaluate the effects of Al and Ni from nanomaterials, aluminas and non-nanometric Ni on seedlings elongation and on tomato plants growth; the quantification of Al and Ni incorporation in seedlings, by neutron activation and a preliminary analysis of nutrient elements present in stems and leaves of plants, by scanning electron microscopy. Non-nanometric Ni inhibited root and hypocotyl elongation in a concentration-dependent manner, while acid alumina and two nanomaterials caused greater elongation of seedlings. Ni and Al incorporation was demonstrated, except for one nanomaterial. In experiments with plants, they were grown in garden soil alone and mixtures also containing soil from Gan Gan, Chubut province, Argentina. The fresh and dry weight of plants aerial parts were significantly lower under treatments in different soil mixtures with Ni(NO3)2.6H2O (190 mg/L) compared to the Control plants (0.33 ± 0.02 vs 0.49 ± 0.10 and 0.005 ± 0.0001 vs 0.007 ± 0.003 g/plant respectively). It was demonstrated that non-nanometric Ni was toxic to the plants. More trials should be carried out to elucidate whether nanomaterials can be related to alterations on nutrient elements and be toxic to tomato plants.

Photosynthesis and chlorophyll fluorescence of Iranian licorice (Glycyrrhiza glabra l.) accessions under salinity stress.

While salinity is increasingly becoming a prominent concern in arable farms around the globe, various treatments can be used for the mitigation of salt stress. Here, the effective presence of Azotobacter sp. inoculation (A1) and absence of inoculation (A0) was evaluated on Iranian licorice plants under NaCl stress (0 and 200 mM) (S0 and S1, respectively). In this regard, 16 Iranian licorice (Glycyrrhiza glabra L.) accessions were evaluated for the effects on photosynthesis and chlorophyll fluorescence. Leaf samples were measured for photosynthetic pigments (via a spectrophotometer), stomatal and trichome-related features (via SEM), along with several other morphological and biochemical features. The results revealed an increase in the amount of carotenoids that was caused by bacterial inoculation, which was 28.3% higher than the non-inoculated treatment. Maximum initial fluorescence intensity (F0) (86.7) was observed in the ‘Bardsir’ accession. Meanwhile, the highest variable fluorescence (Fv), maximal fluorescence intensity (Fm), and maximum quantum yield (Fv/Fm) (0.3, 0.4, and 0.8, respectively) were observed in the ‘Eghlid’ accession. Regarding anatomical observations of the leaf structure, salinity reduced stomatal density but increased trichome density. Under the effect of bacterial inoculation, salinity stress was mitigated. With the effect of bacterial inoculation under salinity stress, stomatal length and width increased, compared to the condition of no bacterial inoculation. Minimum malondialdehyde content was observed in ‘Mahabad’ accession (17.8 μmol/g FW). Principle component analysis (PCA) showed that ‘Kashmar’, ‘Sepidan’, ‘Bajgah’, ‘Kermanshah’, and ‘Taft’ accessions were categorized in the same group while being characterized by better performance in the aerial parts of plants. Taken together, the present results generally indicated that selecting the best genotypes, along with exogenous applications of Azotobacter, can improve the outcomes of licorice cultivation for industrial purposes under harsh environments.

Chemical variability of lemon beebalm (Monarda citriodora Cerv. ex Lag.) during plant phenology

Lemon beebalm (Monarda citriodora Cerv. ex Lag.) is a well-known source of thymol and other active ingredients with recognised antimicrobial properties. However, no previous research investigated the chemical variability of M. citriodora organs during plant phenology. In this paper, above-ground organs of lemon beebalm harvested during three phenological stages were studied for the content and composition of essential oil (EO) and phenolic compounds as well as antimicrobial and antioxidant activity. The EO content in leaves and inflorescences during the full flowering stage was 3.34% and 3.83%, respectively. The phenological stage of plants mainly influenced the content and chemical composition of EO in leaves. The main component of the EOs both from leaves and inflorescences was thymol (52.63–61.83%). The EOs from these organs collected at the full flowering stage inhibited the growth of all the tested microbial strains at the concentration range 0.156–0.625 µL × mL-1. Plant organs differed in the content of total phenolics, flavonoids, and individual phenolic compounds. The effect of phenological stage on these contents was more pronounced in leaves and stems than in inflorescences. Total flavonoid content in stems and inflorescences was higher than in leaves. Leaves harvested during vegetative stage were characterised by the highest level of linarin, a flavone glycoside (80.66 mg × 100 g-1 of dry raw material). All the tested parts of plants were found to be rich in rosmarinic acid, in particular inflorescences (507.41 mg × 100 g-1). The identified high antimicrobial and antioxidant activity of the studied EOs and extracts can be explained by the high content of thymol in EO and rosmarinic acid in the aerial parts of plants.

Functional conservation of an AP2/ERF transcription factor in cuticle formation suggests an important role in the terrestrialization of early land plants.

The formation of a hydrophobic cuticle layer on aerial plant parts was a critical innovation for protection from the terrestrial environment during the evolution of land plants. However, little is known about the molecular mechanisms underlying cuticle biogenesis in early terrestrial plants. Here, we report an APETALA2/Ethylene Response Factor (AP2/ERF) transcriptional activator, PpWIN1, involved in cutin and cuticular wax biosynthesis in Physcomitrium patens and Arabidopsis. The transcript levels of PpWIN1 were 2.5-fold higher in gametophores than in the protonema, and increased by approximately 3- to 4.7-fold in the protonema and gametophores under salt and osmotic stresses. PpWIN1 harbouring transcriptional activation activity is localized in the nucleus of tobacco leaf epidermal cells. Δppwin1 knockout mutants displayed a permeable cuticle, increased water loss, and cutin- and wax-deficient phenotypes. In contrast, increased total cutin and wax loads, and decreased water loss rates were observed in PpWIN1-overexpressing Arabidopsis plants. The transcript levels of genes involved in cutin or wax biosynthesis were significantly up-regulated in PpWIN1-overexpressing Arabidopsis lines, indicating that PpWIN1 acts as a transcriptional activator in cuticle biosynthesis. This study suggests that Arabidopsis WIN1/SHN1 orthologs may be functionally conserved from early to vascular land plants.

Studying the Alkaloids Content in Delphinium oreophilum Huth

Research relevance: plant alkaloids are important in pharmacology based on their high physiological activity, as well as wide range of practical valuable medicinal properties. Most of plants necessary for conservation, cultivation and rational use of each type of plant resources in traditional and medical practice remains an urgent task. Kyrgyzstan is a favorable region for growth of medicinal herbs that is why flora research and study is of great importance. Research objectives: search of the biologically active content of methyllicaconitine alkaloids in roots and aerial parts of the Delphinium oreophilum plant growing in the territory of the Kyrgyz Republic. Research methods: diterpenoid alkaloids methyl lycaconitine, anthranoillicoctonine, lycoctonine, eldelin, eldelidine were obtained by separating the sum of alkaloids. Resulting compounds were analyzed by IR, NMR, Mass spectroscopy. A mixed melt test of the isolated perchlorate with a true sample of methyl lycaconitine perchlorate confirmed compounds identity. Research results: the sum of alkaloids obtained from the roots and aerial parts of Delphinium oreophilum plants collected in the southern and northern slopes of the Kichi Alai ridge. Conclusions: the content of total alkaloids in the roots and aerial parts of the plant growing in the southern slopes was 1.8% and 1% of the weight of the dry plant. The samples collected in the northern slopes contained 0.8% and 0.7% of the total alkaloids, respectively.