Plants Of Different Ages Research Articles

Metals geochemistry and ecological risk assessment in lateritic soils and their transfer to tea plants

ABSTRACT Tea plant cultivation has been demonstrated to change the physicochemical properties of soils and metal bioavailability. The present study reported the geochemistry of four selected metals (Fe, Mn, Cr, and Ni) in lateritic soil cores regarding various depths cultivated with tea plants of different ages (3, 6, and 10 years old). The ecological risk and bioaccumulation of these metals in tea plants were also evaluated. The results indicate the acidic property of tea plant cultivation soils (pH < 4.5) and highlight further soil acidification due to long-term cultivation. The soils were strongly affected by farming methods and showed high levels (average from all soil cores) of total organic carbon contents (4.0% w/w), total nitrogen (2806 mg kg−1), and total phosphorus (1730 mg kg−1). We suggest that the selected metals originated naturally, supported by a high percentage in residual fractions from the results of soil sequential extraction (over 95% for Mn, Fe, and Ni and ∼ 90% for Cr). These metals exhibited no ecological risk to the adjacent environment. Mn showed the highest bioavailability, possibly due to the acidic soils and nitrogen fertiliser applications, increasing the release of Mn from soils. Mn also exhibited the highest bioconcentration factor (BCF) among four metals and 2.4 ÷ 6.5-folds higher BCFs in tea leaves than in roots. Despite the dominant content of Fe in soils (average of 20% w/w), Fe indicated lower amounts in tea leaves than Mn (average of 513 mg kg−1 vs 1354 mg kg−1). This could be attributed to the formation of Fe-rich root coatings on the tea plant root surface as a barrier to prevent Fe from translocating to other higher tea plant parts. Ni and Cr, as potentially toxic metals, were found at the lowest contents in tea leaves with low BCFs, indicating consumer safety in terms of exposure by these metals.

Agave Wilt Susceptibility by Reduction of Free Hexoses in Root Tissue of Agave tequilana Weber var. azul Commercial Plants in the Fructan Accumulation Process.

Agave tequilana stems store fructan polymers, the main carbon source for tequila production. This crop takes six or more years for industrial maturity. In conducive conditions, agave wilt disease increases the incidence of dead plants after the fourth year. Plant susceptibility induced for limited photosynthates for defense is recognized in many crops and is known as "sink-induced loss of resistance". To establish whether A. tequilana is more prone to agave wilt as it ages, because the reduction of water-soluble carbohydrates in roots, as a consequence of greater assembly of highly polymerized fructans, were quantified roots sucrose, fructose, and glucose, as well as fructans in stems of agave plants of different ages. The damage induced by inoculation with Fusarium solani or F. oxysporum in the roots or xylem bundles, respectively, was recorded. As the agave plant accumulated fructans in the stem as the main sink, the amount of these hexoses diminished in the roots of older plants, and root rot severity increased when plants were inoculated with F. solani, as evidence of more susceptibility. This knowledge could help to structure disease management that reduces the dispersion of agave wilt, dead plants, and economic losses at the end of agave's long crop cycle.

Extraction, characterization and properties evaluation of pineapple leaf fibers from Azores pineapple

Pineapple leaves can provide competitive and high-quality fibers for textile purposes. Despite pineapple being cultivated in the Portugues islands there is still a technology gap for the extraction and treatment of Pineapple Leaf Fibers (PALF) in Europe. Since Azorean Pineapple differs significantly from other plants in the bromeliad family, the properties and characterization of its leaf fibers were explored for the first time. Long fibers have been extracted by hand scraping and compared to biological retting at 25 °C for different time periods. It was explored the properties of PALF from plants of different ages (11- and 18-months) and from different zones of the leaves (beginning, middle, and tip). Physical-mechanical properties of Azores PALF were determined, including diameter, linear density, strength, Young's modulus, and elongation at break and characterized by ATR-FTIR, XRD, TGA/DTG, and FESEM to understand their chemical and morphological characteristics. While slight differences were observed between different ages, variations in physical-mechanical properties were notable among fibers extracted from different leaf positions. Extraction of Azores PALF through 25 °C biological retting for 14 days effectively eliminated non-fibrous matter and produced the thinnest and strongest fibers. These fibers ranged between 34.9 and 168.3 μm in diameter, 1.39 and 7.07 tex in linear mass density, 37–993 MPa in tensile strength, 1.0–3.9 % in elongation at break, and 2.4–21.8 GPa in Young's modulus.

The Age of Citrus Cultivars Affects Rooting, Growth and Development of Cuttings

The article presents the results of research conducted to study the effect of the age of citrus varieties on the rooting, growth and development of cuttings. The article also provides valuable information on determining the phenophases of rhizogenesis in cuttings of citrus plants of different ages.

The content of dry matter and chlorophylls in paulownia plants of different ages in the Right Bank Forest Steppe of Ukraine

Purpose. To determine the influence of the main fertilization, the application of cryoprotectant and foliar feeding on the formation of the content of dry matter and chlorophylls a and b in paulownia plantations of different ages. Methods. The research was carried out in 2021–2023 at the experimental plot of the Bila Tserkva National Agrarian University located in the forest plantations in the Right Bank Forest Steppe of Ukraine (Kyiv region). Design of the experiment: factor A – fertilization: 1) without fertilizers, 2) application of organic fertilizer Vermykompost (400 kg/ha) before planting; factor B – application of cryoprotectant: 1) without cryoprotectant, 2) cryoprotectant Mars-EL (0.5 l/ha) applied at the beginning of leaf growth; factor B – foliar application of fertilizers: 1) no treatment, 2) Quantum-AmiNoFrost (1.5 l/ha), 3) SmartGrow Recovery (2.0 l/ha). Results. In the first year of vegetation in the flowering phase, the average content of dry matter of paulownia plants was 44.8%, chlorophylls a and b – 2.6 and 1.5 mg/kg, and in the control treatment – 43.6%, 2.14 and 1.43 mg/kg, respectively. According to the experiment, the highest indicators were obtained in the treatment of fertilizing plantations with organic fertilizer Vermykompost, as well as cryoprotectant Mars-EL and foliar application of anti-stressors Quantum-AminoFrost or SmartGrow Recovery: dry matter content – 46.4 and 46.9%, chlorophyll a – 2.80 and 2.89 mg/kg, chlorophyll b – 1.59 and 1.65 mg/kg, respectively. In the 2-year-old plantations, the average content of dry matter in the treatments was 45.7%, chlorophylls a and b – 2.74 and 1.54 mg/kg, while in the control treatment these indicators were significantly lower: 45.2%, 2.24 and 1.24 mg/kg, respectively. As in the previous year, the maximum contents of dry matter (46.2–46.3%) and photosynthetic pigments (chlorophyll a: 2.89–3.01 mg/kg, chlorophyll b: 1.66–1.70 mg/kg) obtained for combinations of all three factors of the experiment. In the third year of vegetation of paulownia plantations in the flowering phase, on the average, the stems contained 51.2% of dry matter; the content of chlorophyll a in the leaves was 3.95 mg/kg, chlorophyll b – 2.84 mg/kg, in the control variant – 49.7%, 3.71 and 2.51 mg/kg, respectively. The highest results according to the experiment, as in the previous two years, were recorded in the treatment with the complex application of organic fertilizer Vermykompost, cryoprotectant Mars-EL and Quantum-AminoFrost or SmartGrow Recovery: the content of dry matter was 52.5–52.7%, chlorophyll a 4.05–4.07 mg/kg, and chlorophyll b 2.84–2.89 mg/kg. Conclusions. The parameters of the formation of indicators of the content of dry matter and photosynthetic pigments in paulownia plants were largely determined by the agrotechnical measures applied in the experiment, namely, the introduction of the main fertilizer and the treatment of plants during the growing season with cryoprotectant and anti-stress formulations, as well as the age of the plants. In particular, in the first two years of vegetation, the contents of dry matter and chlorophylls a and b were approximately at the same level in the experimental treatments, while in the third year, as the plants developed, they increased significantly. Throughout all the years of the study, the highest indicators of the content of dry matter and photosynthetic pigments were recorded in the treatments with the complex application of all three studied factors: fertilizer, cryoprotectant and foliar feeding.

Greenhouse gas flux from peat with oil palm plants of different ages

The use of peat for agricultural crop cultivation needs to be done carefully by considering water management and peat characteristics. The use of peat for cultivation affects the breakdown of organic matter, which produces CH4 and CO2. CO2 and CH4 are glasshouse gases that cause global warming and impact climate change. The purpose of this activity was to determine the flux of CO2 and CH4 from the peat used for palm oil cultivation at different ages. The gas collection was carried out surrounding and between plants at 50m, 100m, and 150m from the drainage channel. Gas samples were taken using the closed chamber method, and gas was analysed using gas chromatography equipped certain detector. The results of the activity showed that the flux of methane from peat with palm oil trees aged < 3 years tended to be higher than oil palms aged > 3 years, while the CO2 flux was relatively not different between palm oil aged < 3 years and > 3 years. The distance of the presence of the drainage channel affects the CH4 and CO2 fluxes, namely the high CH4 flux at the point near the drainage channel but the low at the CO2 flux. Further and in-depth research is needed to understand GHG flux from peat with different oil palm ages.

Microbial response to nitrogen removal driven by combined iron and biomass in subsurface flow constructed wetlands with plants of different ages

This study investigated the nitrogen removal enhanced by combined iron scraps and plant biomass, and its microbial response in the wetland with different plant ages and temperatures. The results showed that older plants benefitted the efficiency and stability of nitrogen removal, which could reach 1.97 ± 0.25 g m−2 d−1 in summer and 0.42 ± 0.12 g m−2 d−1 in winter. Plant age and temperature were the main factors determining the microbial community structure. Compared with temperature, plant ages affected more significantly on relative abundance of microorganisms such as Chloroflexi, Nitrospirae, Bacteroidetes and Cyanobacteria, and functional genera for nitrification (e.g., Nitrospira) and iron reduction (e.g., Geothrix). The absolute abundance of total bacterial 16S rRNA ranged from 5.22 × 108 to 2.63 × 109 copies g−1 and presented extremely significant negative correlation to plant age, which would lead to a decline in microbial function on information storage and processing. The quantitative relationship further revealed that the ammonia removal was related to 16S rRNA and AOB amoA, while nitrate removal was controlled by 16S rRNA, narG, norB and AOA amoA jointly. These findings suggested that a mature wetland for nitrogen removal enhancement should focus on aging microbes caused by old plants and possible endogenous pollution.

Differences in transcriptomic and metabolomic analyses of metabolites of shoots on tea plants of different ages and relevant regulatory network.

To investigate differences in fresh leaves of tea plants at different ages in gene expression, metabolism, and dried tea quality, and to provide references to a deep exploration on metabolite differential accumulation of fresh leaves of tea plants at different ages as well as the regulation mechanism, two groups of fresh leaves from tea plants at different ages (group JP: 20-, 200-, and 1,200-year tea plants; group YX: 50-, 100-, and 400-year tea plants) were chosen as materials, and their differences in gene expression, metabolites, and metabolic regulatory network were investigated by transcriptomics and metabolomics. A total of 12,706 differentially expressed genes (DEGs) were screened from the fresh tea leaves in the JP group, of which tea-20 vs. tea-200 had the largest number of DEGs, up to 9,041 (4,459 down-regulated genes, 4,582 up-regulated genes). A total of 644 common genes in the fresh leaves of three different ages of tea plants in the JP group were differentially expressed. A total of 8,971 DEGs were screened from the fresh leaf samples of tea plants in the YX group, of which the number of DEGs obtained in the tea-50 vs. tea-400 comparison combination was the largest with a total of 3,723 (1,722 up-regulated genes and 2,001 down-regulated genes). A total of 147 common genes were differentially expressed in the fresh leaves of three different tree ages in the YX group. The pathway enrichment analysis showed that most up-regulated DEGs and their related metabolic pathways were similar in the two groups, and that the metabolic pathways of common significant enrichment included flavonoid biosynthesis, phenylpropane biosynthesis, carbon metabolism, amino acid biosynthesis, and plant pathogen interaction. The metabolomics results showed that 72 and 117 different metabolites were screened from the JP and YX groups, respectively. Most of the different metabolites in the two groups were flavonoids, phenolic acids, amino acids, and their derivatives. Among them, the number of down-regulated flavonoids in older tea plants is generally higher than the number of up-regulated flavonoids. Moreover, according to the sensory evaluation results of dried tea of fresh leaves from tea plants of different ages, tea-1200 and tea-400 showed the highest sensory evaluation scores in their groups. With increase in plant age, the fragrance of the tea was more elegant, and it changed from a dense scent to a faint scent; the tea tasted sweet and its freshness increased, while the sense of astringency was weakened and the concentration declined. Therefore, the quality difference of tea of different tree ages is mainly related to secondary metabolic pathways such as the flavonoid biosynthesis pathway. With increase in tea age, a large number of gene expression in the flavonoid biosynthesis pathway is down-regulated, which reduces the content of bitter flavonoid substances in fresh leaves and makes tea soup more mellow.

Variação sazonal do teor de nutrientes em folhas de abacateiros dos genótipos Geada, Fortuna e Quintal

Abstract Avocado is an important fruit for fresh consumption and as raw material for several industries. In order to obtain good productivity and fruit quality, adequate plant nutrition is essential. However, information on the relationship between time of year, phenology and nutritional status of plants of different genotypes is difficult to compare, as most data are obtained from plants of different ages, planted in soils with different fertility levels, different management strategies and most cultivated under edaphoclimatic conditions different from those of Brazil. This study evaluated the seasonal nutrient content variation of avocado leaves, genotypic differences, the relationship with phenological stages and the periods of greater nutrient content stability in ‘Fortuna’, ‘Geada’ and ‘Quintal’ avocado genotypes cultivated in the municipality of Jardinópolis-SP, Brazil. All plants aged 30 years, were randomly planted within the same area and submitted to the same cultural treatments and management. Nutrient contents are more stable during the flowering phase (July to September) and in the final phase of fruit formation (February to March). In most of the cycle, ‘Geada’ plants have lower S, P and Zn levels compared to ‘Fortuna’ and ‘Quintal’ genotypes. ‘Fortuna’ genotype has higher Ca, Mg and Mn levels than the others at the time of fruit harvest (April to June). In the budding phase of the three genotypes (October), increase in N, P, K, S, Cu, Zn contents and decrease in Ca, Mg and Mn contents were observed.

Leaf area prediction models from growth measurements in Andean blueberry (Vaccinium meridionale Swartz) in the nursery

The Andean blueberry is a high-Andean wild fruit species consumed in fresh or processed form that has high potential due to its antioxidant capacity. Leaf area describes the photosynthetic capacity of plants and is employed as a variable in multiple physiological studies; however, in Andean blueberry (Vaccinium meridionale Swartz), its direct measurement is costly. The aim of this research was to propose models for estimating the leaf area in young Andean blueberry plants using morphometric variables. In the study, 436 Andean blueberry plants of different ages (10 to 26 months) obtained with different methods of asexual propagation (tissue culture or cuttings) were used. Variables, such as dry weight per organ, leaf area, plant height, number of vegetative shoots and number of leaves, were measured. Simple and multiple regressions were performed and the “weighted least squares” technique was used to meet the regression assumptions. Five models with coefficients of determination (R2) greater than 0.81 were proposed. Two models were of the multiple type and employed the number of leaves together with the dry weight of leaves or the total dry weight as predictor variables. The other models were linear and used total dry weight, dry weight of leaves or number of leaves as explanatory variables of leaf area; the number of leaves was a particularly interesting variable due to its non-destructive nature. The models presented could be a useful tool for estimating leaf area in future studies in Andean blueberry.

Electronic Nose Analysis and Statistical Methods for Investigating Volatile Organic Compounds and Yield of Mint Essential Oils Obtained by Hydrodistillation

A major problem associated with the development of medicinal plant products is the lack of quick, easy, and inexpensive methods to assess and monitor product quality. Essential oils are natural plant-derived volatile substances used worldwide for numerous applications. The important uses of these valuable products often induce producers to create fraudulent or lower quality products. As a result, consumers place a high value on authentic and certified products. Mint is valued for essential oil used in the food, pharmaceutical, cosmetic, and health industries. This study investigated the use of an experimental electronic nose (e-nose) for the detection of steam-distilled essential oils. The e-nose was used to evaluate and analyze VOC emissions from essential oil (EO) and distilled water extracts (DWEs) obtained from mint plants of different ages and for leaves dried in the shade or in the sun prior to hydrodistillation. Principal component analysis (PCA), linear discriminant analysis (LDA), and artificial neural networks (ANN) were performed on electrical signals generated from electronic nose sensors for the classification of VOC emissions. More accurate discriminations were obtained for DWEs sample VOCs than for EO VOCs. The electronic nose proved to be a reliable and fast tool for identifying plant EO. The age of plants had no statistically significant effect on the EO concentration extracted from mint leaves.

Genotype and age of industrial plant Jatropha curcas L. affect physico-chemical properties of seed oil

Jatropha curcas, has been established as a plant whose seeds contain a relatively high percentage of oil that is suitable for biodiesel production, among other industrial applications. Seed oil properties of J. curcas may vary depending on soils, age of plant, genotype of the plant, and agro-climatic conditions of a specific geographical region. Studies under such conditions have not yet been conducted. The present study was aimed at investigating the effects of genotype and age of the plant on the physicochemical properties of its seed oil. The seed oil was extracted using n-hexane as a solvent in the Soxhlet extraction apparatus from seed kernel collected from different genotypes and plants of different ages. Oil content in the kernel ranged from 49.78–53.75% (w/w) among the seed samples depending on genetic materials and plant age. The oil content showed very little but significant differences in density and specific gravity among the samples. The highest free fatty acid (FAA) was produced by the kernel oil of 3-year-old plants (7.78%), and 7- and 10-year-old plants gave the lowest FAA (1.26 and 1.31%, respectively). The kernel oil of 7-year-old plants produced the highest iodine value (93.60 mg/g oil) and the kernel oil of 3-year-old plants produced the lowest iodine value (61.10 mg/g oil). Kernel oil of 10-year-old plants gave the lowest (172.98 mg KOH/g) saponification value and 4-year-old Hybrid-3 gave the maximum value (209.97 mg KOH/g oil). The seed oil of Jatropha accessions showed very little difference (39.88–40.85 MJ/kg) for high heating values irrespective of their age. On the other hand, the cetane number varied from 55.32 to 59.58 in the oil samples. The age of plant and seed sources had a significant effect on seed oil content and the physio-chemical properties of Jatropha.

Taif’s Rose (Rosa damascena Mill var. trigentipetala) Wastes Are a Potential Candidate for Heavy Metals Remediation from Agricultural Soil

The current study examines the bioaccumulation potential of Taif rose shrubs by analyzing the shrubs’ wastes. f. At Al-Shafa Highland, four farms with plants of different ages were chosen to collect soil samples and vegetative waste (leaves and stems) for morphological and chemical analysis. The tallest stem and largest crown diameter (184.2 and 243.5 cm, respectively) were found in the oldest (20-year-old) shrubs, which also produced the highest biomass of pruning wastes of stems and leaves (3.9 and 1.3 t/ha, respectively). The 10-year-old shrubs gathered the highest concentration of Co and Pb (1.74 and 7.34 mg kg−1) in the stem and the highest Fe, Mn, and Ni (18.55, 18.60, and 9.05 mg kg−1) in the leaves, while the youngest plants (4 years) accumulated the highest Cr and Zn (0.83 and 13.44 mg kg−1) in their leaves. The highest contents of Cd, Cr, Cu, Fe, Mn, Pb, and Zn were found in the oldest Taif rose stem (34.94, 1.16, 36.29, 49.32, 51.22, 24.76, and 32.51 g ha−1), while the highest contents of Co and Ni were found in the stems of plants that were 10 and 12 years old (3.21 and 9.54 g ha−1, respectively). The Taif rose’s stem and leaves can absorb the majority of heavy metals that have been studied with BAF values greater than one. Significant relationships between various heavy metals in the soil and the same in the stems (Al, Co, and Pb) and leaves (Co, Fe, Mn, Ni, and Pb) of Taif roses have been observed. According to the current findings, the Taif rose is a promising viable and safe crop for heavy metals phytoremediation if it is grown in polluted soil because there is little to no risk of contamination in the use of its end products, high biomass of pruning wastes, and high efficiency of heavy metal removal.

Untargeted Metabolomics and Transcriptomics Reveal the Mechanism of Metabolite Differences in Spring Tender Shoots of Tea Plants of Different Ages.

The metabolites in the tender shoots of the tea plant are the material basis for the determination of tea quality. The composition and abundance of these metabolites are affected by many key factors, and the tea plant’s age is one of them. However, the effect of plant age on the tender shoot metabolites of tea cultivars of different genotypes is poorly understood. Therefore, we used a combination of untargeted metabolomics and transcriptomics to analyze the differential mechanism behind the differences in the metabolites of the spring tender shoots of 7- and 40-year-old tea plants of two tea cultivars of different genotypes. We found that plant age could significantly change the metabolites in the spring tender shoots of tea plants and that flavonoids, and amino acids and their derivatives, were predominant among the differential metabolites. The quantities of most flavonoids in the aged tea plants of different genotypes were upregulated, which was caused by the upregulated expression of differential genes in the flavonoid biosynthesis pathway. We further discovered that 11 key structural genes play key regulatory roles in the changes in the flavonoid contents of tea plants of different plant ages. However, the influence of plant age on amino acids and their derivatives might be cultivar-specific. By characterizing and evaluating the quality-related metabolites of tea cultivars of two different genotypes at different plant ages, we found that whether an old tea plant (40 years old) can produce high-quality tea is related to the genotype of the tea plant.

Community Assembly and Stability in the Root Microbiota During Early Plant Development.

Little is known about how community composition in the plant microbiome is affected by events in the life of a plant. For example, when the plant is exposed to soil, microbial communities may be an important factor in root community assembly. We conducted two experiments asking whether the composition of the root microbiota in mature plants could be determined by either the timing of root exposure to microbial communities or priority effects by early colonizing microbes. Timing of microbial exposure was manipulated through an inoculation experiment, where plants of different ages were exposed to a common soil inoculum. Priority effects were manipulated by challenging roots with established microbiota with an exogenous microbial community. Results show that even plants with existing microbial root communities were able to acquire new microbial associates, but that timing of soil exposure affected root microbiota composition for both bacterial and fungal communities in mature plants. Plants already colonized were only receptive to colonizers at 1 week post-germination. Our study shows that the timing of soil exposure in the early life stages of a plant is important for the development of the root microbiota in mature plants.

An Optimized Tobacco Hairy Root Induction System for Functional Analysis of Nicotine Biosynthesis-Related Genes

Rhizobium rhizogenes-mediated plant hairy root induction is a convenient method for functional study of root-specific genes. To develop an optimized tobacco hairy root induction system and study gene function in nicotine biosynthesis, we investigated hairy root induction by three R. rhizogenes strains, R1601, K599, and LBA9402, on different media with leaf discs from plants of different ages, and we observed that the strain LBA9402 used for explant infection exhibited the highest hairy root induction rate with 4 and 8 week old leaf discs of the tobacco ‘Coker176’ on 2/3MS medium, and it could also be used as a cargo delivering foreign genes to hairy roots. Overexpression of MsSPL12 gene, an alfalfa (Medicago sativa) SQUAMOSA promoter binding protein-like (SPL) transcription factor, significantly improved nicotine production in transgenic hairy roots, reaching 1.38–1.85 mg/g compared to 0.5 mg/g of the controls. Expression analysis of the nicotine biosynthesis and transport-related genes responding to methyl-jasmonate (MeJA) treatment revealed a significant upregulation of NtMPO2 responsible for increased nicotine biosynthesis in MsSPL12 transgenic hairy roots. Our results establish a high-throughput approach for gene functional characterization in the hairy roots of a tobacco elite cultivar, ‘Coker176’, as well as suggest a system for efficiently manipulating tobacco nicotine biosynthesis.

Linking Phyllostachys edulis (moso bamboo) growth with soil nitrogen cycling and microbial community of plant-soil system: Effects of plant age and niche differentiation

Understanding the impacts of plant age on bamboo growth, soil nutrient and functional microorganism can assist in the development of management practices to maximize the benefits of nutrients and functional endophytic and soil microbes in moso bamboo plantations. In this study, moso bamboos of different ages (0.5, 2.5, 4.5 and 6.5 years) were selected. The above-ground biomass, soil properties and endophytic microbes of above-ground tissue and stump root of different age bamboos were quantified, and their interactive relationships were also examined. There were negligible differences in the heights and above-ground fresh biomass among the bamboo plants of different ages, but net nitrogen (N) mineralization and potential nitrification rates of soils were significantly affected by the bamboo ages. The soil nprA gene abundances decreased with the bamboo ages, and soil AOB amoA gene abundances of the 0.5-yr bamboo were significantly higher than those of the other older plants. Average soil urease activities of the 2.5-yr, 4.5-yr and 6.5-yr bamboos were 81.4%, 81.1% and 88.2% lower than those of the 0.5-yr bamboo, respectively. Bacterial diversity indices and richness estimators in the soils were significantly higher than those in the above-ground tissues. Endophytic microbial community structures were more sensitive to the bamboo ages than the soil counterparts, and endophytic microbial community diversities and structures in the above-ground tissues were significantly changed with the bamboo ages. Bacterial and fungal community structures in the above-ground tissues were significantly different from those in the soils. Bamboo ages significantly affected the N transformations in the soils and endophytic community structures, but niche differentiations among the above-ground tissue, stump root and soil outweighed the plant ages in shaping the whole microbial communities of plant-soil system.

Severance of arbuscular mycorrhizal fungal mycelial networks in restoration grasslands enhances seedling biomass

Summary Establishment and growth of grassland plant species is generally promoted by arbuscular mycorrhizal fungi (AMF) when grown in isolation. However, in grassland communities AMF form networks that may connect individual plants of different ages within and between species. Here, we use an ingrowth core approach to examine how mycorrhizal networks influences performance of seedlings in grasslands.We selected four grass and four forb species with known negative or neutral‐positive plant–soil feedback and grew them individually in steel mesh cores filled with living field soil. Cores were placed in six restored grasslands, three grasslands were of relatively young and three were of older successional age.Ingrowing mycorrhizal fungal hyphae were severed twice a week in half of all cores, which resulted into reduced AMF colonization and increased seedling biomass, irrespective of the fields' succession stage, and the plants' grass/forb group, or plant–soil feedback type. In the control cores, root colonization by AMF was negatively correlated to seedling biomass, whereas there was no such relationships in the cores that had been lifted.We conclude that connections to arbuscular mycorrhizal networks of surrounding plants had a negative impact on biomass of establishing forb and grass seedlings.

TRANSIENT EXPRESSION OF REPORTER GENES IN CULTIVARS OF Amaranthus caudatus L.

Local cultivars of A. caudatus: Helios and Karmin were used as plant material. Amaranth is a new pseudocereal introduced in Ukraine. The plant biomass of amaranth is used in medicine, food industry and cosmetology industry. Aim. The purpose of the work was to identify the optimal conditions for the transient expression of reporter genes in Amaranthus caudatus cultivars. Methods. Biochemical and microscopy methods were used in the following work. Seedlings and adult plants of different age were infiltrated with agrobacterial suspensions separately (genetic vector pCBV19 with a uidA gene and genetic vector pNMD2501 with a gfp gene in Agrobacterium tumefaciens GV3101 strain). Results. Transient expression of the uidA and gfp genes was obtained in amaranth plants after conduction series of experiments. The most intensive transient expression of gfp and uidA genes was observed in seedlings infiltrated at the age of 1 day. The maximum fluorescence of the GFP protein was observed on 5th–6th days. Conclusions. It was shown that the cultivar Helios was more susceptible to agrobacterial infection than the cultivar Karmin. The effectiveness of Agrobacterium mediated transformation was from 16% to 95% for the Helios cultivar and from 12% to 93% for the Karmin cultivar. The obtained results indicate that the studied amaranth cultivars can potentially be used for obtaining transient expression of target genes and synthesizing target proteins in their tissues in the future.

Trees and shrubs from a post-industrial area high in calcium and trace elements: the potential of dendroremediation

The aim of the study was to evaluate the metal(loid)s phytoextraction potential of trees: Betula pendula Roth, Pinus sylvestris L. and the shrub Salix viminalis L. Plants of different ages were selected from a post-industrial area with an unusually high content of calcium (Ca) and trace elements in the soil. The content of 39 metal(loid)s in trees and shrub organs and physicochemical soil parameters were determined. A comparison of these species with control plants was also an object of the study. The polluted soil was characterized by worse physicochemical conditions and a much higher content of almost all the analyzed elements in comparison with the control. The older the plants, the greater their total biomass, with the control plant biomass being significantly greater in each case for all treated plants. According to the total content of all determined elements jointly, the most enriched was the oldest, a 7-year-old specimen of S. viminalis. The obtained results suggest that the high Ca concentration and the alkaline reaction (8.83) of polluted soil limit the uptake of most elements by tested plants. It can be concluded that despite the reduction of biomass, this limitation allows plants to better adapt and survive under challenging conditions. Excessive concentration of elements, even nutrients such as Ca, may act as an inhibitory factor for the uptake of other elements. Moreover, phytoextraction ability may significantly vary in different woody plant species and ages, which is an essential practical aspect in dendroremediation application. Novelty statement That is probably the first study to date of trees and shrubs differing in age and growing on post-industrial soil contaminated with calcium (Ca) and selected toxic metals/metalloids. The obtained results show that an alkaline reaction (less than 9) of soil and an unusually high Ca concentration may help the studied tree species to adapt/survive in unfavorable habitat conditions (high concentration of toxic elements). The efficiency of phytoextraction of toxic elements was so high that, especially for forest animals (roe-deer) that consume, e.g., willow shoots, it could pose a serious threat to health and life, both for them and potentially for humans.