Concentrations In Plant Tissues Research Articles

Nitrate fertilization enhances manganese phytoextraction in Tanzania guinea grass: a novel hyperaccumulator plant?

Manganese (Mn) is essential for plants but very toxic at high rates. However, hyperaccumulators can tolerate high Mn concentrations in plant tissue, especially when properly fertilized with N. Tanzania guinea grass (Megathyrsus maximus Jacq.) has been indicated as metal tolerant and a good candidate for Mn phytoextraction due to its fast growth and high biomass. The objective was to evaluate the Mn hyperaccumulator potential of Tanzania guinea grass grown as affected by proportions of nitrate/ammonium (NO3-/NH4+). An experiment in a growth chamber with nutrient solution, combining NO3-/NH4+ proportions (100/0 and 70/30) and Mn rates (10, 500, 1500, and 3000 μmol L-1), was carried out. The highest Mn concentration was verified in plants grown with 100/0 NO3-/NH4+ and Mn at 3000 μmol L-1, reaching up to 5500 and 21,187 mg kg-1 in shoots and roots, respectively, an overall concentration of 13,345 mg kg-1. These numbers are typically seen in hyperaccumulators. At that combination, Mn accumulation in shoots was also the highest, reaching up to 76.2 mg per pot, a phytoextraction rate of 23.1%. Excess Mn increased both H2O2 concentration in roots and non-photochemical quenching and therefore decreased net photosynthesis, stomatal conductance, electron transport rate, and photochemical quenching. Nevertheless, proline concentration in roots affected by excess Mn was high and indicates its important role for mitigating stress since Mn rates did not even affect the dry biomass. Tanzania guinea grass is highly tolerant to excess Mn as much as a hyperaccumulator. However, to show all its potential, the grass needs to be supplied with N as NO3-. We indicate Tanzania guinea grass as a Mn hyperaccumulator plant.

Selenite (IV) and selenate (VI) uptake and accumulation capacity of Lemna minor L. from an aquatic medium

ABSTRACT The uptake of sodium selenite (Se(IV)) and sodium selenate (Se(VI)) from aqueous medium by Lemna minor L. and the influence of different Se concentrations on its growth, morphological and ultrastructural characteristics were studied. L. minor was grown at different concentrations (1, 3, 5 and 10 mg L−1) of Se(IV) and Se(IV). The Se(IV) concentration in the plant tissue ranged between 77.7 (± 4.3) to 453 (± 0) mg kg−1 DW. The Se(VI) concentration in plant tissues ranged between 117 (± 11) to 417 (± 2) mg kg−1 DW. The highest bioconcentration factor for Se(VI) was 127 (± 7) at 3 mg/L, with a Se removal efficiency of 44%. For Se(IV), the highest bioconcentration factor was 77.7 (± 4.3) at 1 mg L−1, which had a Se removal efficiency of 23%. Growth of L. minor was suppressed at 10 mg L−1 Se in both forms. The addition of Se promoted the formation of starch granules in L. minor which occupied a chloroplast area of 74% for Se(IV) and 77% for Se(VI). The efficient uptake of both Se forms by L. minor indicates the potential application of this species for phytoremediation of Se laden wastewaters and its use as an alternative feedstock in biofuel production.

Acetyl Bromide Method for Total Lignin Content Determination in Plant Biomass.

Lignin is a tough biopolymer that gives plants strength and protection. It is also a major obstacle for converting plant biomass into biofuels because it prevents enzymes from accessing the sugar-rich fibers. To optimize biofuel production, we need to measure the lignin content in plant tissues accurately and efficiently. In this protocol, we describe a simple and reliable method to measure the total lignin content in plant tissues. The method uses acetyl bromide, a chemical that dissolves lignin into soluble derivatives and makes it possible to detect them by their absorbance at 280nm. The method consists of two steps: first, we obtained destarched cell wall material from the plant samples, and second, we treat the cell wall material with acetyl bromide and measure the absorbance of the lignin solution. This method can capture all types of lignin and works well with different plant tissues.

Agronomic performance and zinc concentration in plant tissues of several rice fields varieties with zinc sulfate heptahydrate (ZnSO4) fertilization

Agronomic performance and zinc concentration in plant tissues of several rice fields varieties with zinc sulfate heptahydrate (ZnSO₄) fertilization

ДЕСТРУКЦИЯ ФИТОГОРМОНОВ БАКТЕРИЯМИ-СТИМУЛЯТОРАМИ РОСТА РАСТЕНИЙ

Phytohormones serve as regulators of plant growth and development, playing a fundamental role in the adaptation and survival of plants under different conditions. It is well-known that bacteria have the ability to influence plant physiology by producing phytohormones or decreasing their concentration in plant tissues and the surrounding environment through degradation or transformation. Studying these processes is crucial for a deeper comprehension of plant-microorganism interactions. This study presents the capability of bacteria that promote plant growth and development to degrade phytohormones (ABA, 6-BAP, and IAA) in a culture medium using them as the sole carbon and energy source. It was discovered that a significant portion of the selected strains could thrive on a medium containing ABA, 6-BAP, and IAA. However, the growth intensity varied significantly among different substrates. For instance, strains Pseudomonas plecoglossicida 2,4-D (2,4-D), Pseudomonas sp. RZ (RZ), and Pseudomonas plecoglossicida CH5%2 (CH5%2) exhibited equal growth rates on all substrates, but high-performance liquid chromatography (HPLC) results indicated that strain 2,4 D was the most efficient in the degradation of the aforementioned phytohormones. The extent of biodegradation of ABA, 6-BAP, and IAA by this strain during a 10-day cultivation period amounted to 33%, 70%, and 60%, respectively.

INFLUENCE OF LOW POSITIVE TEMPERATURES ON ANATOMICAL CHARACTERISTICS JUGLANS REGIA L. IN VITRO MICROCLONES

Walnut (Juglans Regia L.) is a promising plant for use in modern medicine. We describe the reactions of Juglans Regia L. microclones exposed to cold stress in vitro at the cell and tissue level. Differences in the water content of plant tissues and the anatomical and morphological structure of the stem and leaf of Juglans Regia L. microclones under control and stress conditions are shown. Significant changes in the anatomical parameters of various stem tissues, both upward and downward, and a tendency for the values of the anatomical parameters of the leaf to decrease under cold stress conditions were revealed. It has been suggested that changes in the anatomical characteristics of organs and tissues of Juglans Regia L. microclones may affect the phytochemical content of biologically active substances in them, valuable for pharmacy.

Crinum bulbispermum, a Medicinal Geophyte with Phytostabilization Properties in Metal-Enriched Mine Tailings.

Ancient grasslands are lost through transformation to agriculture, mining, and urban expansion. Land-use change leads to ecosystem degradation and a subsequent loss of biodiversity. Globally, degraded grasslands have become a priority for restoration efforts to recover lost ecosystem services. Although the ecological and social benefits of woody species and grasses are well documented, limited research has considered the use of forbs for restoration purposes despite their benefits (e.g., C sequestration and medicinal uses). The aim of this study was to determine if Crinum bulbispermum (Burm.f.) Milne-Redh. & Schweick., a medicinal geophyte, could form part of restoration initiatives to restore mine soils in grasslands of the South African Highveld. A pot experiment was conducted to assess the performance of C. bulbispermum in a random design, with three soil treatments varying in level of degradation and metal contamination. The plants were monitored for 12 months, and the morphological characters were measured monthly to assess performance and survival. Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the soil and plant tissue concentration of potentially toxic metals. The results indicated that mine tailings negatively affected the growth and development of C. bulbispermum. Although the survival rates indicated that it could survive on tailings, its below-par productivity indicated that the species is not ideal for restoration purposes unless the tailings are ameliorated with topsoil. Although there was root accumulation of metals (Co, Cd, Cu, Mo, and Zn), there was no translocation to the bulbs and leaves, which makes C. bulbispermum suitable for medicinal use even when grown on metal-enriched soil. This species may not be viable for phytoremediation but is a contender to be used in phytostabilization due to its ecological advantages and the fact that it does not accumulate or store metals. These findings underscore the importance of considering geophytes in grassland restoration strategies, expanding their ecological and societal benefits beyond conventional approaches.

A new hyperaccumulator plant (Spergularia rubra) for the decontamination of mine tailings through electrokinetic-assisted phytoextraction

The screening of new effective metal hyperaccumulators is essential for the development of profitable phytoremediation projects in highly degraded environments such as mining areas. The goal of this research was to analyze the phytoextraction potential of the native plant Spergularia rubra to decontaminate and eventually recover metals (phytomining) from the mine tailings (belonging to an abandoned Pb/Zn Spanish mine) in which it grows spontaneously. To do so, the ability of this plant species to accumulate metals was evaluated both under natural conditions and through simple and electrokinetically assisted phytoextraction tests using alternating current and different combinations of voltage gradient (1/2 V cm−1) and application time (6/12 h per day). The complete duration of the greenhouse trial was 64 days, although alternating current was applied only during the last 14 days. The results obtained demonstrated the exceptional effectiveness of S. rubra for metal hyperaccumulation and growth without affecting toxicity in highly contaminated mining waste. Zn was the metal accumulated to a higher extent in the shoots, reaching concentrations up to 17,800 mg kg−1; Pb was mainly accumulated in the roots reaching a maximum concentration of 8709 mg kg−1. Cu and Cd were accumulated to a lesser extent but the bioconcentration factors were much >1. It has been proved that S. rubra is a hyperaccumulator species for Zn and Cd both in natural and greenhouse conditions and, very probably, Pb in wild conditions. The application of AC current did not significantly increase metal concentrations in plant tissues but it was able to increase the aerial biomass of S. rubra by 49.8 %. As a result, the phytoextraction yields of all metals were significantly improved as compared to wild conditions (up to 86 % for Zn). It could open new expectations about the economic viability of recovering high-value metals from mine tailings.

Phytoextraction potential of herbaceous plant species and the influence of environmental factors – A meta-analytical approach

Heavy metals account for a notable share of soil and water body contaminations. For restoring contaminated soils, phytoremediation is considered an eco-friendly and sustainable practice. However, the implementation in the field requires a well-thought-out plant selection and comprehensive knowledge of the influence of various environmental factors. Therefore, a quantitative evaluation of 330 studies was done using a meta-analytical approach. The systematic assessment included the calculation of bioconcentration factors for roots and shoots (BCFROOT, BCFSHOOT) and translocation factors (TF) of 48 herbaceous species, as well as the identification of the most important soil and plant factors that regulate the heavy metal uptake into plant tissues. The results showed substantial variations in roots' and shoots' heavy metal uptake capacity among the diverse plant species. The uptake also varied depending on the type of heavy metal. Most species revealed a higher accumulation of heavy metals in roots than shoots, indicating a limited heavy metal transport from below-ground into above-ground plant parts. Among the different heavy metals, Cd showed the highest median BCFSHOOT and BCFROOT, followed by Zn, Cu, Ni, Cr, and Pb, which can partly be explained by the solubility and plant availability of the elements. The strongest significant and positive correlations of heavy metal contents in plant tissues were found with the total and available soil content. Clay and silt content showed a weak negative, and sand content a slight positive correlation. Further, root, shoot and total biomass revealed weak negative correlations to the plants' heavy metal contents. Overall, this study forms a basis for the minimum accumulation capacities of various species and thus makes an essential contribution to the planning and practical application of phytoremediation projects.

THE EFFECT OF PEPPERMINT, CLOVE, CINNAMON, SAGE AND ORANGE ESSENTIAL OILS ON LACTOBACILLUS BULGARICUS BACTERIA

Essential oils have been mainly used in aromatherapy, but they have gained the attention of the food industry in the last decade due to their ability to control the growth of pathogenic microorganisms. The essential oil content of plant tissue varies according to the stage of development of the plant, the parts of the plant (leaves, flowers, roots, etc.) as well as the method of extraction. Commonly used techniques for extracting essential oils include hydrodistillation, steam distillation (Chialva et al.,1982), solvent extraction, (Chialva et al.,1982) and CO2 extraction (Takeoka et al.,1985). The composition of the extracted oil may vary from one extraction method to another. The essential oils used in this study were: clove, peppermint, cinnamon, sage, orange. Observations were made on extraction yield, MIC for Lactobacillus bulgaricus, and comparative antimicrobial activity with two commonly used antibiotics.

Effects of coastal embankments on seasonal variations in nitrogen storage in the plant-soil systems of Suaeda salsa salt marshes in Eastern China

The impacts of coastal embankments on nitrogen (N) dynamics are of great importance in salt marshes. However, effects of embankments on seasonal N dynamics in the plant-soil systems of Suaeda salsa salt marshes are still not well understood. Therefore, the edaphic moisture and salinity, biomass, N concentrations and storage in different plant tissues; the extent of organic and inorganic N subpools in soil subsystems; as well as N immobilization and mineralization by microorganisms in embanked and neighboring natural S. salsa salt marshes through all four seasons were investigated in Yancheng, Eastern China. Our results revealed that embankments increased the biomass and N storage of dead tissues (e.g., litter), while they decreased the biomass and N storage of live tissues (e.g., living aboveground tissues and roots) of S. salsa through decreased edaphic moisture and salinity. Furthermore, under the influence of embankments edaphic water-dissolvable N, e.g.,edaphic dissolved organic N (EDON) and nitrate and nitrite N (TNN), significantly increased with higher N inputs from S. salsa litter. This water-dissolvable N was an important source of N for plants, which translated to higher N concentrations in live plant tissues. However, this excess absorbed N appeared not to facilitate the growth of plants, which would ultimately return to the soil from plant residues. Our results suggested that the decreased edaphic soil moisture and salinity due to embankments had negative impacts on the biomass and N storage of S. salsa plant tissues, which were likely due to shifts in the edaphic osmotic potential. Subsequently, a cascading butterfly effect may be initiated due to the impaired growth of S. salsa, to which more attention should be paid. This study represents a step forward by providing valuable insights and an improved elucidation of the seasonal plant-soil N dynamics of S. salsa salt marshes.

Effect of spent tea waste, compost and biochar on some growth parameters and concentration of nitrogen, phosphorus and potassium in spinach (Spinacia oleracea L.) under salinity stress

Salinity is a major environmental problem that adversely affects plant growth by increasing soil osmotic pressure and disrupting plant nutrition. Using organic amendments is a viable tool for reducing physiological and morphological effects of excessive soil salinity on plants. To show the impacts of tea waste, compost and biochar on nutrient status and growth parameters of spinach (Spinacia oleracea L.) raised in salinity conditions, this study has employed factorial CRD with two treatments involving soil salinity (2.5 and 8 dS m−1) and organic materials (spent tea waste (STW), spent tea waste compost (STWC) and spent tea waste biochar (STWB)) at 0 and 3% w/w in three replications. As soil salinity increased from 2.5 to 8 dS m−1, fresh weight and dry matter production decreased by 31.5% and 30.4%, respectively. Phosphorous and potassium concentrations in plant tissue also decreased significantly due to the increase in salinity. Organic amendments (except STW) due to their physicochemical properties increased the nutrients uptake and growth parameters of the plant. Compared to other amendments, biochar reduced salinity effects on plant growth more effectively, which is possibly due to its high nutrient adsorbing and water holding capacity. In saline conditions, the highest potassium to sodium ratio belonged to the biochar treatment, which was 3.22 and 2.78 times greater than spent tea waste and compost, respectively. Therefore, it was preferred to change the spent tea waste into biochar before being used as soil amendment.

Продуктивность озимых зерновых культур в зависимости от степени окультуренности почв

The work is devoted to the bioindication of soils from row spacing and trunk strips of an apple orchard, as well as in their natural state. The soil in these places had different properties. Two varieties of winter wheat and one variety of winter rye were sown on the soils. The different cultivation of the soils of apple orchards is most noticeable in meadow-chernozem and chernozem-meadow soils. The degree of soil cultivation in apple orchards affects the vegetative mass and the content of mineral elements in winter wheat and triticale. In the tillering phase, plants accumulate less vegetative mass on less cultivated soil. The water content in the aboveground mass of crops does not depend on the cultivation of the soil. Plants in the process of their development maintain the hydration of tissues necessary for life, therefore, the water content in plant tissues cannot be used in bioindication as a test indicator of soil cultivation. The productivity indicators of the aboveground mass of winter wheat of the Moskovskaya 70 variety, Moskovskaya 39 variety, winter rye of the Chulpan 7 variety and the content of nitrogen, phosphorus and potassium in their plant tissues are generally consistent with water-physical, physico-chemical parameters and with soil bonification data, therefore, these agricultural plants are recommended to be used as test crops when evaluating the degree of cultivation of soils. Keywords: WINTER RYE, WINTER WHEAT, DEGREE OF CULTIVATION, BIOINDICATION, NATURAL LANDS

A simple, easy, and efficient HPTLC method for simultaneous determination of polyamines (putrescine, spermidine, and spermine) in plant tissues

Polyamine analysis has received a lot of attention in recent years because they are important in several physiological processes, including cell proliferation, differentiation, and growth. This study presents the development and validation of a user-friendly and convenient high-performance thin-layer chromatography (HPTLC) method, using benzoyl chloride as a derivatization agent for the analysis of three abundant polyamines. A comparative study with HPLC-MS/MS was performed to evaluate the putrescine, spermidine, and spermine content of plant tissues. The linear ranges for the determination of putrescine and spermine by HPTLC were lower than those of HPLC-MS/MS. Lower LODs were found for polyamine analysis using HPLC-MS/MS except for spermidine. The Pearson correlation coefficients of the two methods for putrescine, spermidine, and spermine were 0.982, 0.998, and 0.980, respectively, which confirms the applicability of both HPTLC-UV and LC-MS/MS methods. According to these results, the optimized HPTLC-UV method may be used as a practical analytical tool for screening polyamine levels in the horticultural, food, and pharmaceutical industries for quality control purposes.

Tracing the fate of microcystins from irrigation water to food chains: Studies with Fragaria vulgaris and Meriones shawi

Microcystins (MCs) are cyanobacterial toxins that can negatively impact human and animal health. This study investigated the bioaccumulation, transfer, depuration, and health risks of MCs in strawberry plants (Fragaria vulgaris) and Meriones shawi animals. The plants were irrigated with 1, 5, 10, and 20 μg/L MCs for 60 days (bioaccumulation phase) and then with clean water for 30 days (depuration phase). The harvested plants (roots and leaves) were then prepared in an aliquot form and used as feed for Meriones shawi. Liquid chromatography-mass spectrometry (LC/MS/MS) was used to measure MC concentrations in plant and animal tissues. The bioaccumulation of MCs was found to be highest in the roots, followed by leaves, fruits, liver, stomach, and fecal matter. The bioaccumulation factor (BAF) was highest in perlite (8.48), followed by roots (5.01), leaves (1.55), stomach (0.87), and fecal matter (1.18), indicating that the parts with high bioaccumulation factor had high translocation of MCs. The transfer of MCs to animal organs was low, and the daily toxin intake of adult consumers of strawberry fruit irrigated with 1, 5, 10, and 20 μg/L MC did not exceed the WHO-recommended limit of 0.04 μg MC-LR/Kg of bw/day. However, fruits from plants irrigated with 10 and 20 μg/L may pose a moderate health risk to children (25 Kg bw), and Meriones' consumption of leaves may pose a significant health risk. After the depuration phase, MC concentration in perlite, roots, leaves, and fruits decreased, indicating that depuration reduced the danger of MC transmission and bioaccumulation. The study also found that glutathione reductase and glutathione S-transferase activity were essential in the depuration of MCs in the tested plants. The findings suggest that legislation regulating the quality of irrigation water in terms of MC concentrations is necessary to prevent detrimental consequences to crops and human exposure.

Towards a mechanistic understanding of animal-ecosystem interactions.

Research Highlight: Ferraro, K. M., Welker, L., Ward, E. B., Schmitz, O. J., & Bradford, M. A. (2023). Plant mycorrhizal associations mediate the zoogeochemical effects of calving subsidies by a forest ungulate. Journal of Animal Ecology, https://doi.org/10.1111/1365-2656.14002. Animals play large roles in ecosystem elemental cycling but predicting effects in diverse contexts remains a substantial challenge. Fundamental to progress is (1) identifying mechanisms by which animals impact nutrient distribution and cycling, and (2) disentangling how environmental context mediates the operation of alternative mechanisms. In an elegant field experiment, Ferraro etal. (2023) provide the first detailed exploration of the impact of nutrient inputs from mammalian parturition on soil functioning and the stoichiometry of plant tissues. The authors find that nitrogen from experimental additions of ungulate parturition material (natal fluids) is rapidly incorporated into microsite soil organic pools and plant tissues. They also find that soil processes (soil microbial biomass, rates of carbon mineralization, nitrogen mineralization and nitrification) and the nitrogen content of plant tissues above- and belowground are increased by addition of parturition material. Notably, the authors identify that increases in some soil processes and plant tissue nitrogen are weaker in microsites dominated by ericoid mycorrhizal plants than those dominated by ectomycorrhizal plants. These findings demonstrate that parturition depositions, a ubiquitous but overlooked mechanism of mammalian impacts on ecosystems, impact ecosystem processes and plant tissue stoichiometry. Furthermore, plant-fungal associations are a predictive axis of context dependency mediating zoogeochemical effects at fine scales. Ferraro etal.'s (2023) novel approach simultaneously advances mechanistic understanding of animal-ecosystem interactions at fine scales and facilitates prediction of ungulate effects on nutrient availability at landscape extents.

Magnesium supplementation alleviates drought damage during vegetative stage of soybean plants.

Our working hypothesis was that magnesium (Mg) supplementation modulates plant performance under low water availability and improves drought tolerance in soybean genotypes. Plants of Bônus 8579, M8808 and TMG1180 genotypes were grown under field conditions and subjected to three water stress treatments (control, moderate and severe stress) and three Mg levels [0.9 (low), 1.3 (adequate) and 1.7 cmolc dm-³ (supplementation)]. After 28 days of drought imposition, the growth parameters, osmotic potential, relative water content, leaf succulence, Mg content and photosynthetic pigments were assessed. In general, drought drastically decreased the growth in all genotypes, and the reductions were intensified from moderate to severe stress. Under adequate Mg supply, TMG1180 was the most drought-tolerant genotype among the soybean plants, but Mg supplementation did not improve its tolerance. Conversely, although the M8808 genotype displayed inexpressive responses to drought under adequate Mg, the Mg-supplemented plants were found to have surprisingly better growth performance under stress compared to Bônus 8579 and TMG1180, irrespective of drought regime. The improved growth of high Mg-treated M8808-stressed plants correlated with low osmotic potential and increased relative water content, as well as shoot Mg accumulation, resulting in increased photosynthetic pigments and culminating in the highest drought tolerance. The results clearly indicate that Mg supplementation is a potential tool for alleviating water stress in M8808 soybean plants. Our findings suggest that the enhanced Mg-induced plant acclimation resulted from increased water content in plant tissues and strategic regulation of Mg content and photosynthetic pigments.

Effect of chronic and humped input of polystyrene microplastics on rice growth

The impact of microplastics (MPs) pollution on farmland is influenced by the type of rainfall and the hydrography of the site. However, it is not clear how the arrival of MPs to farmland through different input modes will affect plant growth. Here, we simulated the effects of polystyrene (PS) MPs chronic input (50 mg/L), humped input (0, 0, 0, 100, 250, 100, 0, 0, 0 mg/L) and without PS MPs input (control) on rice growth through hydroponic experiment. The results showed that the input mode of MPs had a significant effect on the growth of rice. Compared with the control, the chronic input reduced the fresh weight of rice roots, stems and leaves by 61 %, 60 % and 64 %, respectively. Humped input only had a significant effect on the fresh weight of rice roots and stems, which were reduced by 24 % and 17 %, respectively. Both PS MPs input modes significantly reduced the chlorophyll content of plants. However, the chronic input of PS MPs also stimulated the antioxidant system of rice, improved peroxidase (POD) activity, and changed the nutrient content in plant tissues. Overall, chronic input of PS MPs had a greater impact on rice growth. Therefore, it is crucial to consider the input modes of MPs when assessing their effects on plant growth. This study is the first to investigate the effects of different input modes of MPs on plant growth, providing new insights into the pathways through which MPs affect plants.

Melatonin seed priming improves growth and physio-biochemical aspects of Zinnia elegans under salt stress

Salt stress is a major abiotic aspect that inhibits plant development, growth, and productivity of ornamental plants. In recent years, there has been a lot of interest in seed priming and biological treatments for salt stress mitigation in plants. Melatonin (MLT) is a versatile signaling molecule detected in higher plants. Its function is involved in various signaling and physiological processes, particularly under severe environmental conditions. The aim of this study was to assess the performance of different levels of MLT (0, 1, 10, 20 μM) primed zinnia plants (Zinnia elegans cv. ‘Super Yoga’) under salt stress (100 mM NaCl). Salt stress exposure reduced growth and physiological variables and increased oxidative stress, recorded as a rise in stress markers. The results showed that seed priming with MLT improved morphological characteristics of zinnia, such as shoot and root length, shoot diameter, leaf length, root collar diameter, number of roots, root fresh, and dry weight. MLT based seed priming also increased photosynthesis pigments and reduced salt induced oxidative damage by enhancing the activity of antioxidant enzymes (i.e. superoxide dismutase-SOD, peroxidase-POD, and catalase-CAT). The reduction in oxidative stress was recorded as decrease in electrolyte leakage (EL), hydrogen peroxide (H2O2), and malondialdehyde (MDA). Primed plants also showed significant increase in the osmoprotectants proline and glycine betaine, as compared to the non-primed salt stress plants. Exposure of plants to salt stress lead to an increase in sodium (Na+) and potassium (K+) contents in plant tissues in the non-primed plants. However, priming with MLT reduced the uptake of Na+ and improved the uptake of K+ in the leaves of zinnia. Overall, these results provided evidence that MLT seed priming may ameliorate the ill effects of salt-induced oxidative stress in zinnia plants.

Restoration of soils contaminated with PAHs by the mixture of zeolite composites mixed with exogenous organic matter and mineral salts

The major cause of soil degradation (contamination, erosion, compaction) is closely linked to agriculture, i.e., unsustainable agriculture practices, which are reflected in the depletion of the soil organic carbon pool, loss in soil biodiversity, and reduction of C sink capacity in soils. Therefore, the agricultural practice of applying carbon-rich materials into the soil is an attractive solution for climate change mitigation and soil ecosystem sustainability. The paper aimed to evaluate the effectiveness of the addition of organic-mineral mixtures to the mineral salts (NPK), including the exogenous organic matter (lignite) mixed with zeolite-carbon (NaX-C) or zeolite-vermiculite (NaX-Ver) composites in the restoration of soils contaminated with PAHs. The addition of zeolite composites to fertilizer resulted in a significant reduction in soil PAH levels and a corresponding reduction in plant tissue content, without compromising yields, compared to the control and separate application of NPK. A Significant correlation between PAHs and pHH2O, pHKCl, EC and dehydrogenase activity (DhA) was found in soils. The addition of zeolite composites with lignite significantly reduced the content of PAHs in straws, especially following the application of NaX-C. However, in the case of grains, the highest percentage reduction in comparison to NPK was observed for the highest dose of NaX-Ver.