Characteristics and phytotoxicity of hydrochar-derived dissolved organic matter: Effects of feedstock type and hydrothermal temperature.

The dissolved organic matter (DOM) with high mobility and reactivity plays a crucial role in soil. In this study, the characteristics and phytotoxicity of DOM released from the hydrochars prepared from different feedstocks (cow manure, corn stalk and Myriophyllum aquaticum) under three hydrothermal carbonization (HTC) temperatures (180, 200 and 220°C) were evaluated. The results showed that the hydrochars had high dissolved organic carbon content (20.15 to 37.65 mg/g) and its content showed a gradual reduction as HTC temperature increased. Three fluorescent components including mixed substance of fulvic acid-like and humic acid-like substances (C1, 30.92%-58.32%), UVA humic acid-like substance (C2, 25.27%-29.94%) and protein-like substance (C3, 11.74%-41.92%) were identified in hydrochar DOM by excitation emission matrix spectra coupled with parallel factor analysis. High HTC temperature increased the relative proportion of aromatic substances (C1+C2) and humification degree of hydrochar DOM from cow manure, while it presented adverse effects on the hydrochar DOM from corn stalk and Myriophyllum. aquaticum. The principal component analysis suggested that feedstock type and HTC temperature posed significant effects on the characteristics of hydrochar DOM. Additionally, seed germination test of all hydrochar DOM demonstrated that the root length was reduced by 8.88%-26.43% in contrast with control, and the germination index values were 73.57%-91.12%. These findings provided new insights into the potential environmental effects for hydrochar application in soil.

Biochar addition influences C and N dynamics during biochar co-composting and the nutrient content of the biochar co-compost.

This study investigated the effects of corn cob biochar (CCB) and rice husk biochar (RHB) additions (at 0%, 5%, and 10% w/w) on nitrogen and carbon dynamics during co-composting with poultry litter, rice straw, and domestic bio-waste. The study further assessed the temperature, moisture, pH, and nutrient contents of the mature biochar co-composts, and their potential phytotoxicity effects on amaranth, cucumber, cowpea, and tomato. Biochar additions decreased NH4+-N and NO3- contents, but bacteria and fungi populations increased during the composting process. The mature biochar co-composts showed higher pH (9.0-9.7), and increased total carbon (24.7-37.6%), nitrogen (1.8-2.4%), phosphorus (6.5-8.1 g kg-1), potassium (26.8-42.5 g kg-1), calcium (25.1-49.5 g kg-1), and magnesium (4.8-7.2 g kg-1) contents compared to the compost without biochar. Germination indices (GI) recorded in all the plants tested with the different composts were greater than 60%. Regardless of the biochar additions, all composts treatments showed no or very minimal phytotoxic effects on cucumber, amaranth and cowpea seeds. We conclude that rice husk and corn cob biochar co-composts are nutrient-rich and safe soil amendment for crop production.

Electrocoagulation of landfill leachate: Transforming a hazardous residue into a source of irrigation water.

Electrocoagulation of landfill leachate has been widely investigated, however, only few reports include the reuse of the treated water. In this work, treated leachate is evaluated as irrigation water. The main obstacle is the high Sodium Absorption Ratio (SAR=Na+/(Ca2++Mg2+)/2. Reducing this indicator involves decreasing Na+ and increasing Mg2+ or Ca2+. Sodium concentration reduction is difficult by electrochemical methods (E0 = -2.71 V); Ca2+ increasing is not feasible as it precipitates. Hence, the use of different Al-Mg anodes was tested tending to increase Mg2+ concentration in the treated water The alloy 88%wtAl-12%wtMg was able to remove 52.9% of COD, 98.1% of turbidity, 97.9% of color, obtaining a SAR of 8.2 meq·L-1, total hardness (TH) of 64.2 meq·L-1 and a soluble sodium percentage (SSP) of 75.8 meq·L-1. This was achieved by working at a current density of 15 mA cm-2, a treatment time of 15 min and a pH 5.0. The phytotoxicity of the treated leachate was evaluated by the germination index using Lactuca Sativa L., reaching a value of 83.2%, which is considered excellent for irrigation water. During growth, 3-4 primary leaves were observed in seedings after 21 days, similar to when potable water was used. The results demonstrate that electrocoagulation is an adequate treatment technique for the reuse of landfill leachate if appropriated materials are used as anodes working in well selected operational variables.

Impact of saflufenacil and glyphosate-based herbicides on the morphoanatomical and development of Enterolobium contortisiliquum (Vell.) Morong (Fabaceae): new insights into a non-target tropical tree species.

The unregulated use and improper management of herbicides can cause negative effects on non-target species and promote changes in biological communities. Therefore, the current study is aimed at understanding morphoanatomical responses and effects on seedling development induced by the herbicides glyphosate and saflufenacil in Enterolobium contortisiliquum, a non-target tropical species. The plants were cultivated in a greenhouse and subjected to herbicides at doses of 0, 160, 480, and 1440 g a.e ha-1 for glyphosate, and 0, 25, 50, and 100 g a.i ha-1 for saflufenacil. We conducted visual and morphological assessments over 90 days post-application. Leaf samples were collected 12 days after the application for anatomical analysis, and we also performed a micromorphometric analysis of the leaf tissues. Biomarkers of phytotoxicity were identified in plants exposed to both herbicides, even at the lowest doses, including in leaves without visual symptoms. The main morphological alterations were the decrease in growth, stem diameter, and dry mass. Furthermore, the leaves and stems visually exhibited chlorosis and necrosis. Both herbicides triggered anatomical modifications such as significant changes (p < 0.05) in the thickness of leaf tissues, hypertrophy, cell collapse, and changes in epicuticular waxes. However, the alterations induced by glyphosate were more widespread compared to saflufenacil, encompassing alterations in the root system. We confirmed that the different mechanisms of action of each herbicide and the existence of an underground reserve system in this species are intrinsically linked to the morphological and developmental responses described. Our findings suggest that E. contortisiliquum could be a potential bioindicator species for these herbicides in the environment, even at concentrations lower than those typically recommended for field application.

Enhanced competitiveness of Spirodela polyrhiza in co-culture with Salvinia natans under combined exposure to polystyrene nanoplastics and polychlorinated biphenyls.

Micro- and nanoplastics (MNPs) and polychlorinated biphenyls (PCBs) are prevalent in the environment and pose potential threats to ecosystems. However, studies on the phytotoxicity of MNPs and PCBs on primary producers are limited. This study investigated the effects of polystyrene nanoplastics (PS-NPs, 10 mg/L) and 2,2',5,5'-tetrachlorobiphenyl (PCB-52, 0.1 mg/L), on the growth of Spirodela polyrhiza and Salvinia natans, and their impact on plant competitive ability under co-culture conditions. Laser confocal microscopy images revealed that PS-NPs accumulated on the leaf and root surfaces of both species. Combined exposure to PS-NPs and PCB-52 significantly inhibited the average specific and relative growth rates (RGR) of both species, reduced chlorophyll a and b levels, and slightly increased carotenoid content, disrupting the photosynthetic system. PCB-52 exacerbated PS-NPs accumulation on plants, leading to increased hydrogen peroxide (H2O2) and superoxide anion (O2-) production in both roots and leaves. This affects the activity of superoxide dismutase (SOD), peroxidase (POD), malondialdehyde (MDA), and the soluble protein content. The combined treatment with PS-NPs and PCB-52 induced greater ecological stress in both species than the treatment with PS-NPs alone. In addition, the combined treatment with PS-NPs and PCB-52 significantly improved the relative yield and competition balance index of S. polyrhiza, indicating that PS-NPs + PCB-52 enhanced the competitive ability of S. polyrhiza when co-cultured with S. natans. This study confirmed the effects of co-exposure to PS-NPs and PCB-52 on aquatic plant growth and species competition, contributing to better insight into the ecological impacts of MNPs and organic pollutants.

Assessing the impact of leachate irrigation on Medicago sativa (alfalfa) growth, enzymatic responses, and heavy metal accumulation.

In light of the increasing water scarcity and the need for sustainable waste management, the use of landfill leachate for irrigation has emerged as both a solution and a concern, posing potential risks to soil health and plant vitality. This study examined the multifaceted impacts of leachate irrigation on the soil characteristics, plant growth, and enzymatic activities of Medicago sativa (M. sativa). By exposing alfalfa to different concentrations of leachate, we assessed the influence on heavy metal accumulation, physiological parameters, and enzyme functions. The physicochemical profile of the leachate indicated that the pH was within acceptable limits, but the chemical oxygen demand (COD), biochemical oxygen demand (BOD5), and concentrations of lead (Pb) and aluminum (Al) exceeded regulatory standards. Morphological parameters exhibited dual effects: stimulation at lower leachate doses and inhibition at higher leachate doses. Our findings show that soil acts as a buffer, reducing heavy metal uptake by plants. Enzymatic activities, including catalase, peroxidase, and succinate dehydrogenase, fluctuated significantly at higher leachate concentrations, indicating stress responses. This research underscores the interplay between leachate irrigation, plant physiology, and soil health, emphasizing sustainable management to optimize plant growth and minimize environmental impacts. It also stresses refining leachate application protocols to preserve soil and ecosystem health.

Phytotoxic Activity of Sesquiterpene Lactones-Enriched Fractions from Cynara cardunculus L. Leaves on Pre-Emergent and Post-Emergent Weed Species and Putative Mode of Action.

Sesquiterpene lactones (SLs) are compounds that are highly produced in Cynara cardunculus leaves, known for their phytotoxic activity. This study aims to assess SL-enriched fractions' (cynaropicrin, aguerin B, and grosheimin) phytotoxic potentials and putative modes of action, compared to an initial extract, using two approaches: first, against a panel of nine weed species in pre-emergence, and then on Portulaca oleracea L.'s post-emergency stage. The SL-enriched fractions demonstrated greater phytotoxic activity when compared with the C. cardunculus leaf initial extract. The SL-enriched fractions had higher activity at root growth inhibition over the panel tested, doubling the activity in five of them at 800 ppm. Regarding the post-emergence bioassay, the SL-enriched fractions had a higher influence on the plants' growth inhibition (67% at 800 ppm). The SL-effects on the plants' metabolisms were evidenced. The total chlorophyll content was reduced by 65% at 800 ppm. Oxidative stress induction was observed because of the enhancement in MDA levels at 800 ppm compared to control (52%) and the decrease in SOD-specific activity from 4.20 U/mg protein (400 ppm) to 1.74 U/mg protein (800 ppm). The phytotoxic effects of the SL-enriched fractions suggest that they could be used for a future bioherbicide development.

Mitigating risks from atrazine drift to soybeans through foliar pre-spraying with a degrading bacterium.

Herbicides play a crucial role in managing weeds in agriculture, ensuring the productivity and quality of crops. However, herbicide drift poses a significant threat to sensitive plants, necessitating the consideration of ecosystem-based solutions to address this issue. In this study, foliar pre-spraying of atrazine-degrading Paenarthrobacter sp. AT5 was proposed as a new approach to mitigate the risks associated with atrazine drift on soybeans. Exposure to atrazine reduced chlorophyll levels and disturbed the antioxidant system and metabolic processes in soybean leaves, ultimately causing leaves to turn yellow. However, by pre-spraying, strain AT5 successfully colonized the surface of soybean leaves and mitigated the harmful effects of atrazine. This was achieved by slowing down atrazine absorption, expediting its reduction (half-life decreased from 2.22 d to 0.86 d), altering its degradation pathway (enhancing hydroxylation while weakening alkylation), and enhancing the interaction within phyllosphere bacteria communities. This study introduces a new approach that is both eco-friendly and user-friendly for reducing the risks of herbicide drift to sensitive crops, hence promoting the development of mixed cropping.

Innovation for recycling of organic matter through composter with automatic and sustainable temperature recording accessed via Bluetooth/mobile app.

Compost reactors, commonly used in experiments, industrial assays, and home residue treatment systems, have the potential to facilitate composting. Challenges persist in the realm of small-scale composting, encompassing facets such as temperature monitoring, homogenization of the compost mass, management of moisture with the control of leachate generation, and integration with a renewable energy source. This study assesses a pioneering composter prototype endowed with essential features to ensure a pragmatic and secure composting process. This includes the facilitation of remote access to temperature data via Bluetooth and a mobile application. Across successive trials, the scrutinized composter prototype consistently yielded reproducible outcomes, exhibiting a coefficient of variation below 25% for the majority of appraised parameters. In comparison to a conventional reactor, the decomposing residue mixture within the examined prototype manifested elevated temperatures (p < 0.05). Moreover, the tested prototype demonstrated C/N ratio lower than 20/1 within 45 days, a higher final nitrogen concentration, and enhanced germination of seeds that served as phytotoxicity bioindicators. Notably, the prototype needed 46.6% less space, offering improved leachate control, three times faster turning time, temperature monitoring, and reduced fly attraction.

Mechanistic insight into interactive effect of microplastics and arsenic on growth of rice (Oryza sativa L.) and soil health indicators.

Microplastics (MPs) pollution has recently become a major concern for agroecosystems. The interplay between MPs, and heavy metal(loid)s in the soil can intensify the risks to plant growth and human health. The current study investigated the interactive effects of arsenic (As) and biodegradable and petroleum-based conventional MPs on rice growth, As bioavailability, soil bacterial communities, and soil enzyme activities. As-contaminated soil (5 mg kg-1) was treated with conventional MPs i.e., polystyrene (PS) and polyethylene (PE) and biodegradable MPs i.e., polylactic acid (PLA) and polybutylene adipate terephthalate (PBAT) at 0.1 % and 1 % rates. In a pot experiment, rice plants were cultivated in soil co-contaminated with As and MPs. PLA-MPs exhibited significant interactions with As, increasing its bioavailability and impairing rice plant growth by enhancing plant oxidative stress. The results illustrated that T2 treatment (PLA-MPs @ 1 % + As 5 mg kg-1) significantly decreased the root and shoot lengths, root and shoot dry weights as well as the rates of photosynthesis, transpiration, intercellular CO2, and stomatal conductance in rice plants. Biodegradable PLA-MPs @ 1 % resulted in increased uptake of As in rice roots, stems, and leaves by 13.4 %, 38.9 %, and 20.6 %, respectively. In contrast, conventional PE-MPs @ 1 % showed contradictory results with As uptake declined by 2.2 %, 5.1 %, and 9.9 % in rice roots, stem and leaves. Soil enzyme kinetics showed that biodegradable MPs increased the activities of soil catalase, dehydrogenase, and phytase enzymes, whereas both conventional PS and PE-MPs decreased their activities. Moreover, As and PLA-MPs combined stress altered soil bacterial communities by increasing the relative abundance of Protobacteria, Acidobacteria, Chloroflexi, and Firmicutes phyla by 49 %, 29 %, 82 %, and 57 %, respectively. This study provides new insights into MPs-As interactions in soil-plant system and ecological risks associated with their coexistence.

The seed germination and seedling phytotoxicity of decabromodiphenyl ethane to tall fescue under citric acid amendment.

The novel brominated flame retardant decabromodiphenyl ethane (DBDPE) has biological toxicity, persistence, long-range migration and bioaccumulation ability. However, there is currently little research on the phytotoxicity of DBDPE in plants. The perennial herbaceous plant tall fescue (Festuca elata Keng ex E. B. Alexeev) was selected as the model organism for use in seed germination experiments, and the phytotoxicity of DBDPE in the soil of tall fescue was studied. The results indicated that DBDPE had a significant effect on the germination and growth of tall fescue seedlings. Citric acid reduced the stress caused by DBDPE in plants, effectively alleviating the phytotoxicity of DBDPE in tall fescue. The root vitality and protein content significantly increased after the application of citric acid, increasing by 74.93-183.90%, 146.44-147.67%, respectively. The contents of proline and soluble sugars significantly decreased after the application of citric acid, decreasing by 45.18-59.69% and 23.03%, respectively (P < 0.05). There was no significant difference in superoxide dismutase (SOD) or peroxidase (POD) activity in tall fescue seedlings, and the catalase (CAT) activity and malondialdehyde (MDA) content were significantly lower after the application of citric acid, decreasing by 64.62-67.91% and 29.10-49.80%, respectively (P < 0.05). Tall fescue seedlings bioaccumulated DBDPE, with biological concentration factors (BCFs) ranging from 4.28 to 18.38 and transfer factors (TFs) ranging from 0.43 to 0.54. This study provides theoretical support for the study of the toxicity of DBDPE to plants and offers a research foundation for exploring the phytoremediation of DBDPE-contaminated soil by tall fescue.

Seed priming with Fe3O4-SiO2 nanocomposites simultaneously mitigate Cd and Cr stress in spinach (Spinacia oleracea L.): A way forward for sustainable environmental management.

Seed priming with a composite of iron oxide (Fe3O4) and silicon dioxide (SiO2) nanoparticles (NPs) is an innovative technique to mitigate cadmium (Cd) and chromium (Cr) uptake in plants from rooting media. The current study explored the impact of seed priming with varying levels of Fe3O4 NPs, SiO2 NPs, and Fe3O4-SiO2 nanocomposites on Cd and Cr absorption and phytotoxicity, metal-induced oxidative stress mitigation, growth and biomass yield of spinach (Spinacia oleracea L.). The results showed that seed priming with the optimum level of 100 mg L-1 of Fe3O4-SiO2 nanocomposites significantly (p ≤ 0.05) increased root dry weight (144 %), shoot dry weight (243 %) and leaf area (34.4 %) compared to the control, primarily by safeguarding plant's photosynthetic machinery, oxidative stress and phytotoxicity of metals. Plants treated with this highest level of Fe3O4-SiO2 nanocomposites exhibited a substantial increase in photosynthetic and gas exchange indices of spinach plants and enhanced activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) antioxidant enzymes by 45 %, 48 %, and 60 %, respectively. Correspondingly, the relative gene expression levels of SOD, CAT, and APX also rose by 109 %, 181 %, and 137 %, respectively, compared to non-primed plants. This nanocomposite application also boosted the levels of phenolics (28 %), ascorbic acid (68 %), total sugars (129 %), flavonoids (39 %), and anthocyanin (29 %) in spinach leaves, while significantly reducing Cd (34.7 %, 53.4 %) and Cr (20.2 %, 28.8 %) contents in plant roots and shoots, respectively. These findings suggest that seed priming with Fe3O4-SiO2 nanocomposites effectively mitigated the toxic effects of Cd and Cr, enhancing the growth and biomass yield of spinach in Cd and Cr co-contaminated environments, offering a promising sustainable approach for producing metal-free crops.

Effects of the co-exposure of microplastic/nanoplastic and heavy metal on plants: Using CiteSpace, meta-analysis, and machine learning.

Micro/nanoplastics (MNPs) and heavy metals (HMs) coexist worldwide. Existing studies have reported different or even contradictory toxic effects of co-exposure to MNPs and HMs on plants, which may be related to various influencing factors. In this study, existing publications were searched and analyzed using CiteSpace, meta-analysis, and machine learning. CiteSpace analysis showed that this research field was still in the nascent stage, and hotspots in this field included accumulation, cadmium (Cd), growth, and combined toxicity. Meta-analysis revealed the differential association of seven influencing factors (MNP size, pollutant treatment duration, cultivation media, plant species, MNP type, HM concentration, and MNP concentration) and 8 physiological parameters receiving the most attention. Co-exposure of the two contaminants had stronger toxic effects than HM treatment alone, and phytotoxicity was generally enhanced with increasing concentrations and longer exposure durations, especially when using nanoparticles, hydroponic medium, dicotyledons producing stronger toxic effects than microplastics, soil-based medium, and monocotyledons. Dry and fresh weight analysis showed that co-exposure to MNPs and Cd resulted in significant phytotoxicity in all classifications. Concerning the MNP types, polyolefins partially attenuated plant toxicity, but both modified polystyrene (PS) and biodegradable polymers exacerbated joint phytotoxicity. Finally, machine learning was used to fit and predict plant HM concentrations, showing five classifications with an accuracy over 80 %, implying that the polynomial regression model could be used to predict HM content in plants under complex pollution conditions. Overall, this study identifies current knowledge gaps and provides guidance for future research.

Chlorine Dioxide: Antiviral That Reduces the Spread of ToBRFV in Tomato (Solanum lycopersicum L.) Plants.

Tomato brown rugose fruit virus (ToBRFV), being a mechanically transmitted disease, is usually difficult to control; therefore, an effective alternative to reduce transmission and replication in the crop is by spraying with chlorine dioxide (ClO2) during routine crop management. In this research, the efficacy of chlorine dioxide (ClO2) for ToBRFV management in a greenhouse and open field was determined. The phytotoxicity of ClO2 and its effective concentration against ToBRFV in Nicotiana longiflora plants were evaluated. Subsequently, the effect of ClO2 on ToBRFV was evaluated in tomato plants grown in an open field. Finally, the effectiveness of ClO2 on plants inoculated with ToBRFV under greenhouse conditions was evaluated and the number of necrotic local lesions (NLLs) was quantified. The results revealed that ClO2 at 760 mg L-1 did not show phytotoxicity and reduced the number of NLLs in N. longiflora plants. It also decreased ToBRFV transmission and replication in field- and greenhouse-grown tomato plants, improving agronomic parameters. ClO2 reduced replication in plants inoculated with different amounts of ToBRFV inoculum in a greenhouse. N. longiflora leaves expressed lower numbers of NLLs when inoculated with ClO2-treated tomato plant extracts. Finally, the results demonstrate that ClO2 represents an effective management alternative when used by direct application to plants. To our knowledge, this is the first study where the use of an antiviral compound is carried out under field and greenhouse conditions.

Enhanced degradation of aqueous caffeine via cylindrical dielectric barrier discharge plasma: Efficacy and toxicity insights.

An environmentally friendly approach for caffeine degradation was explored in this study utilizing cylindrical dielectric barrier discharge (CDBD) plasma. The current-voltage characteristics and the plasma parameters of the CDBD, such as the electron temperature, electron density, density of nitrogen excited states, vibrational temperature, and rotational temperature, were assessed through electrical and optical characterization respectively. Fourier-transform infrared spectroscopy (FTIR) was employed to evaluate the reactive oxygen and nitrogen species (RONS) in the plasma-treated air. The physicochemical properties of deionized water (DW) were measured. To gain a deeper insight into the role of RONS in caffeine degradation, their concentrations in DW were analyzed. Furthermore, the effects of initial concentration, sample volume, and pH on caffeine degradation were investigated. The highest degradation of caffeine was 94% at initial concentration of 50 mg L-1, sample volume 50 mL and in neutral pH. Liquid chromatography-mass spectrometry (LC-MS) was then used to propose the degradation pathway for caffeine. The major reactive species involved in caffeine degradation was ozone. Finally, the phytotoxicity and cytotoxicity of caffeine were assessed before and after plasma treatment with plasma-treated caffeine (PTC) showing minimal toxicity to both plants and cells.

Tetracycline but not sulfamethazine inhibits early root growth of wild grassland species, while seed germination is hardly affected by either antibiotic.

Seed germination and early growth of grassland species might be influenced by veterinary antibiotics that are extensively released into agricultural habitats. Therefore, we tested impacts of the commonly used antibiotics tetracycline and sulfamethazine, single and in mixture, on seed germination and seedling root growth of six typical species of temperate European grasslands (Carum carvi, Centaurea jacea, Galium mollugo, Plantago lanceolata, Silene latifolia, Dactylis glomerata). In standardised germination experiments, we assessed three germination variables (germination percentage, mean germination time, synchrony of germination) and one post-germination variable (seedling root length) under different environmentally realistic antibiotic concentrations (0.1, 1, 10 mg l-1 and a water control). While the germination variables were only irregularly and weakly affected by both antibiotics, seedling root length was strongly reduced by tetracycline, but not by sulfamethazine. Among the test species, D. glomerata was most sensitive to tetracycline with the average root length reduced up to 81 % in the 10 mg l-1 treatment. Its germination behaviour, however, was almost insensitive to the two antibiotics. Mixture effects were only shown in relation to the germination of single species, where the binary mixture produced effects but not the two single antibiotics or, conversely, effects of single antibiotics were lost in the mixture. These findings highlight the potential threat of plant regeneration from seed by veterinary antibiotics, particularly affecting early root growth and potentially influencing plant population growth in natural habitats.

Insight into physiological and biochemical markers against formaldehyde stress in spider plant (Chlorophytum comosum L.).

Formaldehyde is a prominent volatile organic compound and also considered as an indoor air pollutant. Chlorophytum comosum, an indoor plant, has been reported to metabolize indoor formaldehyde. But the phytotoxic effects of formaldehyde, being a pollutant, on C. comosum are not well explored. Furthermore, C. comosum responses that can be considered as markers at the physiological and biochemical level against formaldehyde stress are not yet investigated. Therefore, the current research study was aimed to evaluate such potential markers against formaldehyde in C. comosum. Briefly, C. comosum was exposed to 5-, 10-, and 20-ppm formaldehyde doses in an airtight glass chamber. Plant samples were then taken to analyze morpho-anatomical, physiological, and biochemical responses after short (2, 4, and 6 h), medium (12 and 24 h), and extended durations (48 and 96 h) for each tested dose. Application of 10 and 20 ppm formaldehyde doses leads to a significant incline in enzymatic antioxidants. Formaldehyde concentration of 10 ppm leads to a maximum increase in catalase (30.30 U/mg of protein), guaiacol peroxidase (135.64 U/mg of protein), and superoxide dismutase (44.76 U/mg of protein) compared to their respective controls. A significant change is also observed in non-enzymatic parameters, including total phenolic content, which ranged from 3.62 mg GAE/g (control) to 10.51 mg GAE/g, total antioxidants vary from 27.37% (control) to 85.05% in 20 ppm formaldehyde, respectively. However, formaldehyde application negatively affected the physiological responses of C. comosum by reducing its photosynthetic rate, transpiration rate, and stomatal conductance. Additionally, extended exposure of C. comosum to 10- and 20-ppm formaldehyde doses leads to visible leaf damage. Principal component analysis indicated that enzymatic parameters including SOD, CAT, and GPX and non-enzymatic parameters including MDA, TPC, TFC, TAOs, carotenoids, TSS, and intercellular CO2 contributed the most to the total variance. Thus, these parameters have potential to serve as physiological and biochemical markers in C. comosum against formaldehyde stress.

Response of crop seed germination and primary root elongation to a binary mixture of diclofenac and naproxen.

Non-steroidal anti-inflammatory drugs, diclofenac (DCF) and naproxen (NPX), represent a group of environmental contaminants often detected in various water and soil samples. This work aimed to assess possible phytotoxic effects of DCF and NPX in concentrations 0.1, 1 and 10 mg/L, both individually and in binary mixtures, on the seed germination and primary root elongation of crops, monocots Allium porrum and Zea mays, and dicots Lactuca sativa and Pisum sativum. Results proved that the seed germination was affected by neither individual drugs nor their mixture. The response of primary root length in monocot and dicot species to the same treatment was different. The Inhibition index (%) comparing the root length of drug-treated plants to controls proved to be approximately 10% inhibition in the case of dicots lettuce and pea, and nearly 20% inhibition in monocot leek, but almost 20% stimulation in monocot maize. Assessment of the binary mixture effect confirmed neither synergistic nor antagonistic interaction of DCF and NPX on early plant development in the applied concentration range.

Assessment and monitoring of leather effluent discharge from Dewas and Ranipet and their computational approach.

The swift pace of industrialization, urbanization, and burgeoning populations propel the surge in demand for manufactured goods and infrastructure. The wastewater produced during leather processing comprises a cocktail of organic and inorganic chemical contaminants that have the potential to affect the environment. This study focuses on conducting a comparative physico-chemical, analytical, in vitro, and in silico toxicity assessment and monitoring of leather effluent discharged from two different areas, namely, Dewas and Ranipet. The physicochemical analysis of collected effluents revealed higher levels of biochemical oxygen demand, chemical oxygen demand, total dissolved solids, total suspended solids, and heavy metals than the permissible limit fixed by the Central Pollution Control Board (CPCB). The X-ray powder diffraction analysis of both samples identified the existence of crystalline and amorphous phases. The functional composition of compounds was identified through the analysis of Fourier-Transform Infrared Spectroscopy, which revealed the existence of C-H, O-H, N-H, C = O, C=C, and C≡C stretching vibrations. A variety of compound derivatives, including amines, organic acids, organometallic compounds, alcohols, hydrocarbons, esters, aldehydes, ketones, aromatic, and organogermanium, were identified by Gas Chromatography-Mass Spectrometry. An assessment and monitoring of the phytotoxicity of effluent on the germination of Vigna radiata seeds reveals that (100%) of both Dewas and Ranipet leather effluents inhibited seed germination by 33.34% and 100%. The incorporation of Absorption-Distribution-Metabolism-Excretion-Toxicity (ADMET) analysis improved comprehension of the toxicity profiles of the GC-MS-identified compounds. Moreover, the result of docking studies revealed that cytochrome P450 showed the highest binding affinity towards 1,3-benzodioxol-2-one, hexahydro-cis with an affinity score of - 7.1 kcal/mol. The overall research revealed that the leather effluents from Dewas and Ranipet exhibit significant toxicity, highlighting the necessity of better wastewater management. In the future, innovative treatment methods and environmental friendly processes can be developed to minimize the detrimental effects of leather effluents.

Drugs in the environment - Impact on plants: A review.

Medicines, like food, are necessities. Many of the commonly used pharmaceuticals, especially antibiotics and NSAIDs end up in the environment and are detected in it (especially in water) at concentrations in the ng·L-1- µg·L-1 range. Although the concentrations of individual drugs in the environment are low, their high biological activity can cause them to be toxic to the environment. This review analyzes and summarizes the effects of drugs, primarily antibiotics and NSAIDs on photosynthesizing organisms, i.e., algae, aquatic and terrestrial plants. Acute drug toxicity to algae and plants occurs most often at high, often non-existent environmental concentrations, while sublethal effects occur at low drug concentrations. The review also points out the problems associated with ecotoxicological studies and the lack of systemic solutions to better assess the risks associated with the presence of drugs in the environment.