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The phytotoxicity and removal of atrazine and S-metolachlor in sterile duckweed systems were estimated in this study. Herbicides were added at environmentally relevant ranges: 0–400 µg/L for atrazine or 0–200 µg/L for S-metolachlor in systems with Spirodela polyrhiza or Lemna minor. Toxicity biomarkers, i.e., changes in plant biomass, surface area, chlorophyll fluorescence parameters, pigments, lipid peroxidation, protein concentration, and antioxidative enzyme activities in plants were estimated after 7 days. S. polyrhiza (RGRbiomass-EC50 = 164.8 µg/L) was more tolerant to atrazine than L. minor (RGRbiomass-EC50 = 101.0 µg/L). Atrazine caused damage to photosystem II (ΦM), a reduction in electron transport between PSII and PSI (Φ′M), as well as disruption in energy distribution pathways (decrease in qPrel and increase in UQFrel), most prominently in L. minor. However, L. minor (RGRbiomass-EC50 = 128.9 µg/L) was more tolerant to S-metolachlor than S. polyrhiza (RGRbiomass-EC50 = 15.5 μg/L). The highest sensitivity of S. polyrhiza to S-metolachlor was attributed to a decrease in absorbed energy used in photochemistry (qPrel) and an increase in lipid peroxidation, indicating that S. polyrhiza plants were experiencing oxidative stress. Residual pesticide analysis in the water after seven days allowed us to conclude that plants were responsible for reducing up to 16.5% of atrazine and 28.7% of S-metolachlor in the duckweed system. S. polyrhiza showed higher atrazine phytoremediation capacity than L. minor. S. polyrhiza was more efficient at an environmentally relevant concentration of S-metolachlor (25 μg/L) and L. minor at higher concentrations (200 μg/L). [ABSTRACT FROM AUTHOR]

Water hyacinth (Eichhornia crassipes) is considered a prospective free-floating aquatic plant potentially used to address current issues on food, energy, and the environment. It can grow quickly and easily in various tropical and subtropical environments as long as it has access to adequate light and water to support photosynthetic growth. Ecosystems are threatened by their invasive growth and remarkable capacity for adaptation. However, managing this plant can result in valuable products. This paper demonstrates particle technologies that might be used to utilize water hyacinths, including brake pads, fertilizer, bioenergy, animal feed, phytoremediation agents, bioplastics, and adsorbents. This study is accompanied by a discussion based on the conducted experiments and currently available literature, providing readers with a clearer understanding. Water hyacinth's capacity to absorb macro- and micro-nutrients, nitrogen, and phosphorus makes it a good plant for phytoremediation. The prospect of producing cellulose makes it prospective as a biomass energy source and livestock feeding. Further, it can be transformed into high-cellulose content particles for applications in bioplastics, brake pads, and adsorbents. The current reports regarding education of water hyacinth to student also were added. Finally, issues and suggestions for future development related to the use of water hyacinths are discussed. This study is expected to provide comprehensive knowledge on how to turn invasive water hyacinth plants into valuable products. [ABSTRACT FROM AUTHOR]

Salvinia auriculata Aublet is a floating aquatic plant, capable of absorbing the excess of nutrients and water contaminants and can be used in effluent treatment plants. The ability to survive in degraded areas may be related to the association with beneficial bacteria capable of promoting plant growth. However, little is known about the microbiota associated with this aquatic plant and its potential application to the aquatic environment. In this sense, this work aims to identify bacteria associated with S. auriculata that could be able to promote plant growth. Eighteen bacterial strains were identified by sequencing of the 16S rRNA gene, belonging to the genera Agrobacterium, Bacillus, Curtobacterium, Enterobacter, Pseudomonas, Siccibacter, and Stenotrophomonas. All isolates produced indole compounds, 12 fixed N2, and 16 solubilized phosphate. A new strain of Enterobacter (sp 3.1.3.0.X.18) was selected for inoculation into S. auriculata. For this purpose, 500 mL of nutrient solution and 1 g of the plant were used in the control and inoculated conditions. Enterobacter inoculation promoted a significant increase (p ≤ 0.05) in fresh plant biomass (17%) after 4 days of cultivation. In summary, the present study characterized 18 plant-growth-promoting bacteria isolated from S. auriculata with potential for biotechnological application, such as the production of bioinoculants or biomass resources, to protect or improve plant growth under conditions of stress. [ABSTRACT FROM AUTHOR]

Antibiotics with significant environmental toxicity, e.g., tetracyclines (TCs), are often used in large quantities worldwide, with 50–80% of the applied dose ending up in the environment. This study aimed to investigate the effects of exposure to tetracycline hydrochloride (TC) and minocycline hydrochloride (MIN) on L. minor. Our research evaluated the phytotoxicity of the TCs by analyzing plant growth and biomass and evaluating assimilation pigment levels and fluorescence. The research was extended with the ability potential of duckweed as a tool for removing TCs from water/wastewater. The results demonstrated that both TCs influenced Ir, Iy, biomass, and photosynthetic efficiency. The uptake of TC and MIN by duckweed was proportional to the concentration in the growth medium. The TC was absorbed more readily, reaching up to 8.09 mg × g−1 of dry weight (DW) at the highest concentration (19.2 mg × L−1), while MIN reached 6.01 mg × g−1 of DW. As indicated, the consequences of the influence of TC on plants were slightly smaller, in comparison to MIN, while the plants could biosorb this drug, even at the lowest tested concentration. This study has shown that using plants for drug biosorption can be an effective standalone or complementary method for water and wastewater treatment. [ABSTRACT FROM AUTHOR]

In order to understand the effect of subsurface flow constructed wetland on the treatment of aquaculture tail water, we constructed three subsurface flow wetlands (Ipomoea aquatica, Eichhornia crassipes, philoxeroides) to compare the effects on tail water purification of grass carp ponds, and analyzed the mechamism of microorganisms. The effects of treatment of ponds for tail water of ponds with different hydraulic loads, drainage, suspension and drainage conversion were discussed, and the diversity and composition of microbial community of subsurface flow constructed wetland were also discussed. The results showed that in Ipomoea aquatica, Eichhornia crassipes, philoxeroides groups, the removal rates of TP, NH+4-N and CODMn was the highest respectively, for 24. 7%, 25. 1% and 25%; When the system was shut down, the removal rates of NH+4-N was the lowest in in Ipomoea aquatica, Eichhornia crassipes, philoxeroides groups, for - 526. 07%, - 871. 08%, and -1 196. 46%; When the system was under the low hydraulic load (5. 76 m 3/d), in Ipomoea aquatica, Eichhornia crassipes, philoxeroides groups, the removal rates of CODMn, NH+4 and TP was the highest respectively, for 30. 4%, 42. 5% and 22. 1%. For the microbial community diversity, the Shannon, Ace and Chao 1 index of Ipomoea aquatica groups were the highest, while for Simpson index, the Alternanthera philoxeroides groups was the highest. A total of 5131 samples were identified from the samples of the three aquatic plants groups, which were annotated to 45 phyla, 293 orders and 974 genera. And total of 5 021 OTU samples were obtained from the Ipomoea aquatica groups in drainage, suspension and drainage conversion period, including 47 phyla, 294 orders and 953 genera. The study has shown that aquatic plant subsurface flow constructed wetland had a certain purification effect on aquaculture tail water, while the purification effect will reduce when the water shut down, and the purification effect of low hydraulic load was greater than that of high and medium. The diversity and composition of microbial communities affected the purification effect of subsurface flow constructed wetland on the tail water of aquaculture ponds. [ABSTRACT FROM AUTHOR]

Aquatic plants are grown in aquaria for their beauty and to maintain the quality of water. The explants of Lobelia cardinalis L. were obtained from the Aquatic Plant Center Co., Ltd., Thailand. In vitro clonal propagation offers alternative strategy for its rapid clonal multiplication. In this study, multiple and rapid propagations of Lobelia cardinalis L. with tissue culture techniques were aimed. Highly efficient and repeatable in vitro regeneration protocol was established from nodal segments of Lobelia cardinalis L. Various concentrations and combinations of various plant growth regulators (PGRs) were employed to induce multiple shoots, shoot elongation, number of leaves and rooting of shoots to obtain complete plantlets of Lobelia cardinalis L. Among 2 PGRs such as 6-benzylaminopurine (BAP) and a-Naphthalene acetic acid (NAA) tested for multiple shoot induction. Regenerated shoots had a higher number of shoots on MS medium contained cytokinins with auxins. The maximum shoot proliferation (100 %), number of shoots per explant (6.20 ± 0.51 shoots), shoot length (11.67 ± 0.69 mm) and number of leaves per explant (58.10 ± 0.38 leaves per explant) were observed in MS medium supplemented with 1.0 mg/L BAP and 2.0 mg/L NAA. Rooting was achieved within 3 to 4 weeks on all the rooting media, but MS medium augmented with 1.0 mg/L indole-3-butyric acid (IBA) produced the maximum number of strong and healthy roots (11.70 ± 0.27 roots). The regenerated complete plantlets with healthy roots and shoot system were transferred to 3.5 cm diameter black net plastic pots containing rockwool medium and successfully acclimatized with a survival rate of 100 % in the greenhouse and no phenotypic variations were observed among regenerated plants. The success of this protocol offers highly efficient method of the plant multiplication, which would be beneficial for plant tissue culturist, and nursery people where regular supply of plants is a large number required. This protocol can be utilized for commercial scale propagation. [ABSTRACT FROM AUTHOR]

Plant absorption via aquatic plants is vital for the deep purification of treated wastewater. This study aimed to determine the removal efficiencies of nitrogen and phosphorus for different aquatic plants and the effect of monochromatic light as compared to white light. Five plants (i.e., Iris pseudacorus, Oenanthe javanica, Zantedeschia aethiopica, Ipomoea aquatica Forssk. and Sagittaria trifolia) were cultured in prepared wastewater and radiated by white, red, green and blue LED lamps with 8 h radiation per day, respectively. After 4 d of cultivation, the O. javanica and S. trifolia exhibited relatively better growth status and higher TP removal rates (90%). The blue light radiation played a key role in the TP uptake of the tested plants. The N removal rates of plants were relatively lower (10–40%), limited by the low COD content. The S. trifolia exhibited the highest efficiency, and red light promoted the removal of TN and NO3−-N, whereas NH4+-N removal was driven by blue light radiation. So, O. javanica and S. trifolia coupled with blue and red lamps as supplementary light were suggested for the deep purification of municipal treated wastewater. The effect of intensity and ratio of monochromatic lights could be a direction for further research. [ABSTRACT FROM AUTHOR]

Life cannot exist without water. Water scarcity is caused by massive groundwater decline. Water contamination is the most common problem spreading worldwide quicker than ever, alongwith anthropogenicwater scarcity. Since tainted water can harm health, water contamination is also contributing to water scarcity. Heavy metals in drinking water have plagued most Asian, African, and European nations for decades. Studies reveal that heavy metals have caused damage in Pakistan, India, and China. This study detects heavy metals in groundwater and treats them with phytoremediation along the river Kabul in district Charsadda. It also measures pH, EC, TDS, turbidity, fluoride, phosphates, nitrites, and nitrates. All indicatorsmeet the WHO and national environmental quality criteria for drinking water, except for turbidity, which exceeds the limit of =5 NTU in four examined regions, reaching a maximum of 9.99 NTU. Chemical parameters were within the standard limits, except for high concentrations of arsenic (As) and cadmium (Cd) in samples from S2 (15.20 µg/L) and S1 (20.50 µg/L) compared to WHO's 10 and 5 µg/L standards. However, the limit is within EPA Pakistan's 50 and 100 µg/L standards for drinking water, which Pakistan still follows. Heavymetals can harmhealth, even at lowlevels. Since themajority of the study area's population relies on groundwater for drinking and other needs, heavy metal pollution of the groundwater can cause many ailments. Thus, phytoremediation is increasingly vital to reduce these heavy metals to WHO limits to protect human health and the environment. [ABSTRACT FROM AUTHOR]

The development of a checklist of non-native aquatic plants in the Brantas River is very important from an ecological perspective. The checklist of non-native aquatic plants provides valuable information for the development of effective management and mitigation strategies. The main objective of this study was to provide a detailed checklist of non-native aquatic plants present in the Brantas River, East Java, Indonesia. Sampling was conducted at several locations along the river, where site selection included differences in habitat and environmental conditions, from Blitar (upstream), Trenggalek (midstream), Kediri (midstream), and Jombang (downstream). At each selected site, five 1 x 1m quadrats were randomly placed along the riverbank and within the waterbody using a stratified random allocation within each habitat type (shallow area, slow-flowing section, tributary mouth). Comprehensive identification of physiological and ecological characteristics of non-native species was based on published books and scientific journals. The result of this research showed that there are several non native invasive aquatic plants in Brantas River, viz. the alligator weed, Ludwigia, water lettuce, floating fern, frogbit, parrot feather, Hydrilla, Ambulia, Lemna, water chestnut, Cabomba, and the water hyacinth, Azolla. We recommend management control through mecanical, biological and chemical alternative. [ABSTRACT FROM AUTHOR]

The global concern over trace and heavy metal contamination in aquatic environments necessitates the development of effective remediation strategies. Using aquatic plants for heavy metal removal is a relatively economical and sustainable technology worldwide. This study involved collecting sediment and aquatic plant samples (Acanthus ilicifolius, Typha elephantina, and Cynodon dactylon) from a highly urbanized estuary to analyze metal concentrations in sediment, assess ecological risks, and explore the phytoremediation potential. Trace and heavy metals were detected using Energy Dispersive X-ray Fluorescence Spectroscopy (EDXRF). The sediment metal concentrations were found in decreasing order of Fe, Ti, Mn, Rb, Zr, Zn, Sr, Cu, Co, and As. Fe, Sr, and As concentrations were below certified values, whereas Cu, Zn, and Rb exceeded them. Cumulatively, the pollution load index (PLI) values were close to 1 (0.845), indicating that the study area is likely experiencing metal pollution. The Contamination Factor (CF) values, ranging from 1 to 3, indicated a moderate degree of sediment pollution for Ti, Mn, Cu, Zn, and Rb. The Enrichment Factor (EF) values similarly showed moderate enrichment for these metals, with Cu exhibiting the highest degree of enrichment. Ecological risk assessment highlighted the only metal, Cu, as posing the greatest risk among the studied metals. In terms of phytoremediation potential, the bioconcentration factor (BCF) followed the decreasing order of C. dactylon > A. ilicifolius > T. elephantina for most metals, with low BCF values (<1) indicating low accumulator potential. However, the translocation factor (TF) values for Zn (1.464) and Rb (1.299) in A. ilicifolius species were greater than 1, indicating low accumulation potential but hyper-metabolizing capabilities, allowing the plant to accumulate metals in its aerial parts, making it effective for phytostabilization. [ABSTRACT FROM AUTHOR]

Using biomass to develop and obtain environmentally friendly and industrially applicable biomaterials is increasingly attracting global interest. Herein, cellulose nanocrystals (CNCs) and lignin nanoparticles (LNPs) were extracted from Lemna minor L., a freshwater free-floating aquatic species commonly called duckweed. To obtain CNCs and LNPs, two different procedures and biomass treatment processes based on bleaching or on the use of an ionic liquid composed of triethylammonium and sulfuric acid ([TEA][HSO4]), followed by acid hydrolysis, were carried out. Then, the effects of these treatments in terms of the thermal, morphological, and chemical properties of the CNCs and LNPs were assessed. The resulting nanostructured materials were characterized by using Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) spectroscopy, thermo-gravimetric analysis (TGA), and scanning electron microscopy (SEM). The results showed that the two methodologies applied resulted in both CNCs and LNPs. However, the bleaching-based treatment produced CNCs with a rod-like shape, length of 100–300 nm and width in the range of 10–30 nm, and higher purity than those obtained with ILs that were spherical in shape. In contrast, regarding lignin, IL made it possible to obtain spherical nanoparticles, as in the case of the other treatment, but they were characterized by higher purity and thermal stability. In conclusion, this research highlights the possibility of obtaining nanostructured biopolymers from an invasive aquatic species that is largely available in nature and how it is possible, by modifying experimental procedures, to obtain nanomaterials with different morphological, purity, and thermal resistance characteristics. [ABSTRACT FROM AUTHOR]

Aquatic plants play a key role in the structuring and functioning of shallow lake ecosystems. However, eutrophication often triggers shifts in plant communities and species diversity, especially in the early stages when the water is still clear. Additionally, water depth is an important factor regulating aquatic plant communities. We conducted a 50-day mesocosm study to investigate how water depth (50 cm and 100 cm) affected the functional traits (vertical expansion versus horizontal colonisation) of 20 aquatic plants under eutrophic clear-water conditions. Among the selected species, the submerged plants Hydrocotyle vulgaris and Limnophila indica exhibited higher plant height or biomass in deeper water, while the emergent plants Myriophyllum aquaticum showed the opposite trend. Additionally, Ludwigia peploides subsp. stipulacea exhibited better vertical growth than the remaining species, and the submerged species Vallisneria denseserrulata had better horizontal colonisation. There was a positive correlation between plant height and rhizome length, indicating the absence of a trade-off between vertical growth and horizontal expansion. Our findings suggest an overall resilience of aquatic plants to varying water depths within our study range and highlight the importance of analysing functional traits when selecting appropriate species in freshwater ecosystem restoration, particularly in the face of climate change-induced water depth fluctuations. [ABSTRACT FROM AUTHOR]

In order to study the structure, diversity, potential ecological functions and differences of the rhizosphere microbial community of different floating bed plants in inland river basin, six root species of EFBs plants, including Cyperus involucratus, Iris pseudacorus, Thalia dealbata, Iris tectorum, Canna indica and Pontederia cordata, were collected during the vigorous growth period located in the Chishui River, a secondary tributary of the Tuojiang River. Through high-throughput sequencing of bacterial 16S rRNA fragments and bioinformatics methods, the microbial community composition, biodiversity, and potential ecological functions were analyzed. The results show that Proteobacteria is absolutely dominant in the rhizosphere bacteria of six floating bed plants, with an abundance of 47. 5% ~ 72. 2% . On the condition that the environment of plant growth is relatively similar and the spatial distance is relatively close, the abundance of dominant populations at the genus level of different floating bed plants is still quite different. The microbial community diversity from large to small is I. tectorum, C. indica, I. pseudacorus, C. involucrate, T. dealbata and P. cordata. The rhizosphere bacteria composition of I. pseudacorus and I. tectorum is relatively similar. The abundance of nitrification / denitrification functional bacterial communities in the rhizosphere of C. involucrate is higher, while the abundance of degrading aromatic compounds functional bacterial communities in the rhizosphere of P. cordata is significantly higher than the other five plants. In plants with longer roots, taller height, and greater biomass, the abundance of Gemmobacter in the rhizosphere microbiome is significantly higher. There is a positive correlation between plant growth indicators and nitrogen transformation of some rhizosphere bacteria. The research results can provide reference for study on rhizosphere microbial community of floating bed plants and ecological floating bed construction. [ABSTRACT FROM AUTHOR]

Salinity is one of the most significant abiotic stresses for plant growth. This study aims to study how salinities on the C. demersum L plant, by using sodium chloride (NaCl) and sodium sulfate (Na2SO4) separately as well as in combination, affect fresh weight, relative plant growth, total chlorophyll and protein, and proline content. The experiments were conducted for 14 days. The result showed that the effect of Na2SO4 salt is more toxic than NaCl. Whereas the combined experiments with both salts show that their effects together were more harmful to the plant species at the same concentrations. The findings also revealed that high salt concentrations had a significant impact on the morphological and physiological characteristics. In the experiment assessing the impact of salt stress on plant growth and physiology, the treatment with a combination of 75 mM NaCl and 75 mM Na2SO4 resulted in significant reductions in several key parameters compared to the control group. Specifically, the treatment led to decreases in fresh weight (from 18.742 g to 5.723 g), dry weight (from 2.543 g to 0.845 g), relative growth rate (from 1.236 to 0.380), total chlorophyll content (from 10.212 µg/g to 2.699 µg/g), and protein content (from 42.03% to 30.180%). Additionally, this salt stress condition was associated with an increase in proline content, indicating a physiological response to the imposed salt stress. These results highlight the negative effects of elevated salt concentrations on plant growth and metabolic functions. [ABSTRACT FROM AUTHOR]

The combined morphological features of Stratiotes (Hydrocharitaceae) pollen, observed with light and electron microscopy, make it unique among all angiosperm pollen types and easy to identify. Unfortunately, the plant is (and most likely was) insect-pollinated and produces relatively few pollen grains per flower, contributing to its apparent absence in the paleopalynological record. Here, we present fossil Stratiotes pollen from the Eocene of Germany (Europe) and Kenya (Africa), representing the first reliable pre-Pleistocene pollen records of this genus worldwide and the only fossils of this family discovered so far in Africa. The fossil Stratiotes pollen grains are described and compared to pollen from a single modern species, Stratiotes aloides L. The paleophytogeographic significance and paleoecological aspects of these findings are discussed in relation to the Hydrocharitaceae fossil records and molecular phylogeny, as well as the present-day distribution patterns of its modern genera. [ABSTRACT FROM AUTHOR]

At present, the situation regarding heavy metal pollution in aquatic environments is becoming more and more serious. The bioaccumulation of heavy metals in aquatic plants causes obvious phytotoxicity, which can also induce secondary pollution in the aquatic environment. Zinc and copper, as indispensable elements for plant growth, are also prominent heavy metals in water pollution in China, and their concentrations play a crucial role in plant growth. In this study, we investigated the response of Pistia stratiotes (P. stratiotes) to different concentrations of Zn and Cu, and the results showed that plant growth and photosynthesis were inhibited under both Zn (1, 2, 4, and 8 mg/L) and Cu (0.2, 0.4, 0.8, and 1 mg/L) stresses. The relative growth rates of P. stratiotes under 8 mg/L Zn or 1 mg/L Cu stress were 6.33% and 6.90%, which were much lower than those in the control group (10.86%). Meanwhile, Zn and Cu stress caused insignificant change in the relative water contents of plants. The decrease in phlorophyll fluorescence parameters and chlorophyll contents suggested the significant photoinhibition of Zn and Cu stress. Chemical analysis of plant root exudates showed that the root secretion species obtained by gas chromatography–mass spectrometry (GC–MS) mainly included amino acids, alkanes, aldehydes, ketones, phenols, and more. Compared with the control group, the influence of Zn or Cu on the reduction in relative amounts of exudates was greater than that on the increase. The results of this study provide important data for the utilization of P. stratiotes in heavy metal-polluted water environments. [ABSTRACT FROM AUTHOR]

Life cannot exist without water. Water scarcity is caused by massive groundwater decline. Water contamination is the most common problem spreading worldwide quicker than ever, along with anthropogenic water scarcity. Since tainted water can harm health, water contamination is also contributing to water scarcity. Heavy metals in drinking water have plagued most Asian, African, and European nations for decades. Studies reveal that heavy metals have caused damage in Pakistan, India, and China. This study detects heavy metals in groundwater and treats them with phytoremediation along the river Kabul in district Charsadda. It also measures pH, EC, TDS, turbidity, fluoride, phosphates, nitrites, and nitrates. All indicators meet the WHO and national environmental quality criteria for drinking water, except for turbidity, which exceeds the limit of ≤5 NTU in four examined regions, reaching a maximum of 9.99 NTU. Chemical parameters were within the standard limits, except for high concentrations of arsenic (As) and cadmium (Cd) in samples from S2 (15.20 μg/L) and S1 (20.50 μg/L) compared to WHO’s 10 and 5 μg/L standards. However, the limit is within EPA Pakistan’s 50 and 100 μg/L standards for drinking water, which Pakistan still follows. Heavy metals can harm health, even at low levels. Since the majority of the study area’s population relies on groundwater for drinking and other needs, heavy metal pollution of the groundwater can cause many ailments. Thus, phytoremediation is increasingly vital to reduce these heavy metals to WHO limits to protect human health and the environment.

We investigated the asymmetric reduction of β-keto esters using aquatic plants as whole-cell biocatalysts under darkness and illumination by fluorescent light. The (S)- β-hydroxy esters were obtained with high enantiomeric excess (ee) values. Regardless of the light conditions, the amount of (R)- β-hydroxy ester produced did not change significantly as the substrate concentration increased, whereas the yield of (S)- β-hydroxy ester increased substantially. Moreover, increasing the quantity of plants resulted in a significant increase in the production of (S)- β-hydroxy ester and a slight increase in the production of (R)- β-hydroxy ester, reducing the ee value. The reaction proceeded more efficiently for substrates bearing bulkier ester moieties, of which the tert-butyl ester gave the best results. Ultimately, we concluded that aquatic plants can be used as whole-cell biocatalysts for preparing optically active β-hydroxy esters. This result represents a new use of aquatic plants and contributes to the achievement of carbon neutrality.

Salvinia auriculata Aublet is a floating aquatic plant, capable of absorbing the excess of nutrients and water contaminants and can be used in effluent treatment plants. The ability to survive in degraded areas may be related to the association with beneficial bacteria capable of promoting plant growth. However, little is known about the microbiota associated with this aquatic plant and its potential application to the aquatic environment. In this sense, this work aims to identify bacteria associated with S. auriculata that could be able to promote plant growth. Eighteen bacterial strains were identified by sequencing of the 16S rRNA gene, belonging to the genera Agrobacterium, Bacillus, Curtobacterium, Enterobacter, Pseudomonas, Siccibacter, and Stenotrophomonas. All isolates produced indole compounds, 12 fixed N2, and 16 solubilized phosphate. A new strain of Enterobacter (sp 3.1.3.0.X.18) was selected for inoculation into S. auriculata. For this purpose, 500 mL of nutrient solution and 1 g of the plant were used in the control and inoculated conditions. Enterobacter inoculation promoted a significant increase (p ≤ 0.05) in fresh plant biomass (17%) after 4 days of cultivation. In summary, the present study characterized 18 plant-growth-promoting bacteria isolated from S. auriculata with potential for biotechnological application, such as the production of bioinoculants or biomass resources, to protect or improve plant growth under conditions of stress.

[Objective]To screen the dominant species in constructed wetlands suitable for application to swine wastewater. [Method] Four aquatic plants including iris,canna,cress and pickerelweed were selected to monitor the effects of different hydraulic retention times on the concentration of chemical oxygen demand (COD),total nitrogen (TN),total phosphorus (TP) and ammonia nitrogen (NH4 + -N) in wastewater through a vertical flow constructed wetland device. The purification effect of the four aquatic plants on wastewater was analyzed. [Result] With the delay of hydraulic retention time,the concentrations of COD,TN,TP,and NH4 + -N in wastewater in constructed wetlands gradually decreased,and the purification effect improved. When the hydraulic retention time was 5 days,the removal rates of COD and NH4 + -N by iris were the highest,which were 61. 80% and 68. 35%,respectively;the removal rates of TN and TP by pickerelweed were the highest,which were 30. 92% and 81. 53%,respectively. [Conclusion]The purification effect of constructed wetlands on pig wastewater was better by planting iris and pickerelweed. [ABSTRACT FROM AUTHOR]

Riverine macrophytes are increasingly understood to influence both the physical and chemical dynamics of rivers by creating biogeochemical hotspots and stabilizing benthic sediments. They contribute carbon and nutrients to both aquatic and adjacent terrestrial ecosystems through senescence and herbivory. Here, we report the relationships between Justicia americana biomass, stem length, and stem density, and % carbon (%C), % nitrogen (%N), C:N, δ15N, and δ13C relationships between tissues types (roots, stems, and leaves). Additionally, we report the effects of land use on the plant's tissue. We found that (1) J. americana stem density and dry biomass were positively correlated (P < 0.001); (2) δ13C and %N were significantly different in leaf and root tissue; (3) δ13C and δ15N were both positively correlated across tissue types; (4) Leaf C:N was less than ½ of root and stem tissue; (5) %C in leaf tissue was positively correlated (P < 0.05) with forest cover and negatively correlated with urbanization and watershed area; and (6) provide evidence that J. americana utilizes a C3 photosynthetic pathway. Overall, this study provides novel insight into the ecology of J. americana by elucidating the nutritional quality of different plant tissues and stoichiometric changes in the plant in response to land use. [ABSTRACT FROM AUTHOR]

This study evaluated the treatment efficiency of municipal wastewater from Phetchaburi in Thailand in an alternated 5-day flooding and 2-day drying wetland system with two plants species, namely, Canna indica and Heliconia psittacorum. The efficiencies of biochemical oxygen demand (BOD5) treatment were in the ranges of 90.5% ± 4.8% and 86.9% ± 7.3% for Canna and Heliconia, respectively. Those of chemical oxygen demand (COD) treatment were in the ranges of 75.5% ± 7.9% and 75.3% ± 9.0% for Canna and Heliconia, respectively. Both plants' removal efficiencies of TN, NH4-N, and TP were greater than 40%. Lead and cadmium accumulation in both plants significantly differed between the upper and lower parts of the plants. However, the lead and cadmium accumulation in Heliconia were greater than their accumulation in Canna. Although Canna had a higher nutrient removal efficiency than Heliconia, there are many varieties of Canna in Thailand. These results indicate that the variety of Canna does not affect the nutrient removal efficiency. In conclusion, a wetland system with alternated flooding and drying conditions can be applied in communities where BOD5 and COD are the dominant wastewater pollution characteristics. Both ornamental plants are suitable absorbents for lead and cadmium, and although the accumulation is lower in Canna than in Heliconia for both heavy metals, the difference was not significant. [ABSTRACT FROM AUTHOR]

Antibiotics with significant environmental toxicity, e.g., tetracyclines (TCs), are often used in large quantities worldwide, with 50–80% of the applied dose ending up in the environment. This study aimed to investigate the effects of exposure to tetracycline hydrochloride (TC) and minocycline hydrochloride (MIN) on L. minor. Our research evaluated the phytotoxicity of the TCs by analyzing plant growth and biomass and evaluating assimilation pigment levels and fluorescence. The research was extended with the ability potential of duckweed as a tool for removing TCs from water/wastewater. The results demonstrated that both TCs influenced Ir, Iy, biomass, and photosynthetic efficiency. The uptake of TC and MIN by duckweed was proportional to the concentration in the growth medium. The TC was absorbed more readily, reaching up to 8.09 mg × g−1 of dry weight (DW) at the highest concentration (19.2 mg × L−1), while MIN reached 6.01 mg × g−1 of DW. As indicated, the consequences of the influence of TC on plants were slightly smaller, in comparison to MIN, while the plants could biosorb this drug, even at the lowest tested concentration. This study has shown that using plants for drug biosorption can be an effective standalone or complementary method for water and wastewater treatment.

Plant absorption via aquatic plants is vital for the deep purification of treated wastewater. This study aimed to determine the removal efficiencies of nitrogen and phosphorus for different aquatic plants and the effect of monochromatic light as compared to white light. Five plants (i.e., Iris pseudacorus, Oenanthe javanica, Zantedeschia aethiopica, Ipomoea aquatica Forssk. and Sagittaria trifolia) were cultured in prepared wastewater and radiated by white, red, green and blue LED lamps with 8 h radiation per day, respectively. After 4 d of cultivation, the O. javanica and S. trifolia exhibited relatively better growth status and higher TP removal rates (90%). The blue light radiation played a key role in the TP uptake of the tested plants. The N removal rates of plants were relatively lower (10–40%), limited by the low COD content. The S. trifolia exhibited the highest efficiency, and red light promoted the removal of TN and NO3−-N, whereas NH4+-N removal was driven by blue light radiation. So, O. javanica and S. trifolia coupled with blue and red lamps as supplementary light were suggested for the deep purification of municipal treated wastewater. The effect of intensity and ratio of monochromatic lights could be a direction for further research.

The global concern over trace and heavy metal contamination in aquatic environments necessitates the development of effective remediation strategies. Using aquatic plants for heavy metal removal is a relatively economical and sustainable technology worldwide. This study involved collecting sediment and aquatic plant samples (Acanthus ilicifolius, Typha elephantina, and Cynodon dactylon) from a highly urbanized estuary to analyze metal concentrations in sediment, assess ecological risks, and explore the phytoremediation potential. Trace and heavy metals were detected using Energy Dispersive X-ray Fluorescence Spectroscopy (EDXRF). The sediment metal concentrations were found in decreasing order of Fe, Ti, Mn, Rb, Zr, Zn, Sr, Cu, Co, and As. Fe, Sr, and As concentrations were below certified values, whereas Cu, Zn, and Rb exceeded them. Cumulatively, the pollution load index (PLI) values were close to 1 (0.845), indicating that the study area is likely experiencing metal pollution. The Contamination Factor (CF) values, ranging from 1 to 3, indicated a moderate degree of sediment pollution for Ti, Mn, Cu, Zn, and Rb. The Enrichment Factor (EF) values similarly showed moderate enrichment for these metals, with Cu exhibiting the highest degree of enrichment. Ecological risk assessment highlighted the only metal, Cu, as posing the greatest risk among the studied metals. In terms of phytoremediation potential, the bioconcentration factor (BCF) followed the decreasing order of C. dactylon > A. ilicifolius > T. elephantina for most metals, with low BCF values (A. ilicifolius species were greater than 1, indicating low accumulation potential but hyper-metabolizing capabilities, allowing the plant to accumulate metals in its aerial parts, making it effective for phytostabilization.

Here we confirm the first accurate distributional record of Lemna turionifera Landolt (Lemnoideae, Araceae) in Korea. The nomenclator, Elias Landolt (1926–2013), had collected the species in Korea, but to date, there have been no other identifiers of this species. A Lemna species collected from Andong showed the key characters of L. turionifera: pigmented fronds, consistently-sized papillae along the middle vein, purple-colored root base, and turion forming. The chloroplast DNA sequence of the atpF-atpH intergenic spacer of our Lemna sample was identical or quite similar (99.8%–100%) to L. turionifera in Landolt's collection. Although we could not find flowers, fruits, or seeds during a field survey, after 15 days of indoor incubation, we were able to observe the flowering of L. turionifera. The flower was protogynous, and the spathe was reddish.

Aldrovanda vesiculosa L. is a globally endangered aquatic plant, with only two reintroduced populations known in Japan. In October 2022, we found a population of this species with nearly 10,000 individuals in an agricultural pond in Ishikawa Prefecture. This paper describes the estimated population size, habitat conditions, and the results of a genetic comparison with other populations by comparing its nrDNA (internal transcribed spacer;) and cpDNA (trnL intron and trnL–trnF spacer) sequences. All the DNA sequences from voucher specimens and GenBank data, including the population discovered in the present study, were identical. Based on the evidence, we presume that this A. vesiculosa population is a wild one.

Global changes are responsible for the movement of species. While many research emphasize the spread of alien or invasive alien species, the rapid spread of rare, native species is poorly study. In our studies, we focused on Trapa natans, a species that is considered a strictly protected plant species in Europe, but is considered an alien invasive species in North America and Australia. The aim of the study was to analyze the historical and current occurrence of T. natans at the northern range of this species (Poland, Central Europe) and, based on future climate projections (wordClim), to determine its potential spread in Europe by modeling the occupation area of available habitats in Europe. We found a rapid spread of T. natans in Poland associated with increasing temperatures. Statistical analyzes showed that the mean temperature of the warmest quarter and precipitation of the driest month are the most important climatic variables determining habitat suitability for T. natans. The model for 2021–2040 showed an expansion of habitats suitable for the species to the north (Great Britain and Ireland, Scandinavia), to the east (Germany and Central Europe), to the northeast (Eastern Europe, e.g., Lithuania, Latvia), and to the south (Italy and Southern Europe). In the next two time periods (2041–––2060 and 2061–––2080), the models showed that the entire European area is suitable for colonization by the species, with the exception of the high mountain regions and Spain. T. natans is a representative species whose distribution and recent range changes allow us to track aquatic species feedbacks to climate change in the species’ home range and is a good ecological indicator of global warming. The message for conservationists is that the status of species classified as rare needs to be urgently reviewed.

Urban freshwater ecosystems often involve the introduction of predator species that affect biodiversity via both direct and indirect effects of predation, altering the distribution of prey species. Yet, limited research has explored indirect effects on aquatic invertebrates in urban pondscapes. Here, we use Dytiscidae as our study taxon to investigate how predator-prey interaction modifies the habitat use and habitat selection of macroinvertebrates in ponds of an urban landscape. We sampled dytiscids in 11 ponds with, and 15 ponds without fish, in Helsinki, Finland, during 2018 – 2020, and emergent plant cover in pond margins as a proxy for the quantity of prey refuges. We found (i) at the pond scale, vegetation cover can mitigate the negative effects of predators on dytiscid species richness and abundance, and dytiscids prefer microhabitats with bulrush and sedges to microhabitats with no vegetation or common reeds, reflecting the importance of providing aquatic plants with high structural complexity as prey refuges. (ii) At the landscape scale, small-sized dytiscids favour fishless habitats, and the community-weighted mean body size of dytiscids has seasonal fluctuations, with smaller body sizes in May and June than in July in fishless ponds, indicating that dytiscids select habitats to regulate their investment in vigilance according to their life cycles. Our findings highlight that predation can alter the habitat use and habitat selection of aquatic invertebrates. Mitigating predation risk at both the habitat scale and the landscape scale is crucial to facilitate the fitness of aquatic invertebrates, especially small-sized species, to promote their diversity in urban pondscapes.

AbstractFlowering rush (Butomus umbellatus L.) is an invasive perennial monocot found along the United States (U.S.).–Canadian border which can grow into large monotypic mats that can cause water use issues. Currently, there are two known cytotypes, diploid and triploid, within the invaded range; however, basic ecological research is lacking on the diploid cytotype. Ecological niche modelling (ENM) was done on three known populations of the diploid cytotype, alongside a global site model, to determine site-specific abiotic influences and potential suitability within the U.S. The ENM was constructed using climatic and soil variables from public sources with resultant models compared to currently known populations of flowering rush throughout the U.S. Diploid flowering rush populations and the global site models were highly reliant on precipitation in the driest month (27–39% model contribution) and one site was highly reliant on precipitation seasonality (38% model contribution). Diploid flowering rush populations in this study displayed different responses towards abiotic factors; however, seasonal signaling of precipitation patterns are highly important. Furthermore, diploid flowering rush is predicted to invade numerous areas with less than suitable habitat which should warrant further monitoring to prevent further spread.

Co-pollution of antibiotics and heavy metal copper (Cu) is common in freshwater environments because of their wide use as antimicrobial agents, especially in aquaculture. However, the toxic effects of coexisting antibiotics and heavy metals on aquatic plants remain unclear. This study investigated the effect of four antibiotics (i.e., enrofloxacin, ENR; tetracycline, TC; sulfamethoxazole, SMX; erythromycin, ERY), Cu, and their mixture on the growth and physiological responses of Hydrilla verticillata (L.f.) Royle. Results showed that the four antibiotics exhibited toxic effects on the growth and physiological indicators of H. verticillata, and root elongation was the most sensitive endpoint of the phytotoxicity test. The median effect concentration (EC50) of root elongation indicated that TC (EC50 = 10.05 mg/L) has the highest level of growth toxicity, and the toxicity of ENR to aquatic plants was close to TC (EC50 = 10.44 mg/L), followed by SMX (EC50 = 20.08 mg/L). However, there was no significant toxic effect of 20 mg/L ERY on the root elongation. Hydrophobicity may be a key factor affecting the phytotoxicity of antibiotics. Moreover, antagonistic toxic effects were observed under ENR + Cu, TC + Cu, SMX + Cu, and ERY + Cu co-exposures at all the experimental concentrations (0.01–20 mg/L). Due to the concentrations of antibiotics in natural waters usually with ng/L levels, our results suggested that environmental antibiotic concentrations probably pose low ecological risk to aquatic plants and indicated the H. verticillata could be used as phytoremediation candidate to remove antibiotic or antibiotic–Cu pollutions in general nature water. [ABSTRACT FROM AUTHOR]

Studies on large‐scale geographic patterns of aquatic plant diversity can promote research on the generality of macroecological patterns in different ecosystems. Here, we compiled a checklist of 889 aquatic angiosperms in China, including 738 helophytes (emergent and marshy plants) and 151 hydrophytes (submerged, free‐floating, and floating‐leaved plants). We explore the geographic patterns and environmental correlates of aquatic plant diversity based on six metrics including species richness (SR), weighted endemism (WE), phylogenetic diversity (PD), phylogenetic endemism (PE), the standardized effect size of phylogenetic diversity (PDses), and the standardized effect size of mean phylogenetic distance (MPDses). Our results show that the diversity of aquatic plants in China is extremely uneven, with high diversity in southeastern China and low diversity in northwestern China, and the geographic patterns of taxonomic and PD are generally consistent. The pattern of helophytes differs from that of hydrophytes. Notably, the wavy‐shaped pattern of aquatic plant diversity (especially SR and PD for hydrophytes) across the latitude observed in this study is not consistent with those previously observed for aquatic plants in other continents. Climatic variables and water environmental variables are the main drivers of aquatic plant diversity in China; however, the effects of individual variables differ between helophytes and hydrophytes. Water environmental variables have a greater impact on PDses and MPDses of hydrophytes than those of helophytes. Overall, our work provides insight into understanding the large‐scale patterns of aquatic plant diversity and is a critical addition to previous studies on the macroecological pattern of terrestrial organisms. [ABSTRACT FROM AUTHOR]

The development of aquatic plant beds can obstruct boat traffic, hinder the practice of water activities, and impact the functioning of freshwaters. In order to mitigate their effects, mechanical removal is often the preferred management solution. The objective of this study was to test, in mesocosms, the effect of frequency (none, one, and two cuts) and cutting dates (May and/or July) on the regeneration and colonization capabilities of the aquatic plant Egeria densa, an invasive alien species in France. The cutting date had no effect on the capabilities of E. densa, but the two cuts significantly reduced the plant's biomass. Removal produced numerous fragments, which exhibited very high survival and anchoring rates. However, summer removal produced fragments with lower regeneration and colonization abilities compared to fragments from spring cutting. Mechanical removal only temporarily reduced the biomass of the aquatic plant beds and could promote the formation of new beds from the fragments generated by management and dispersed by water flow. [ABSTRACT FROM AUTHOR]

Emergent plant Zizania latifolia, floating aquatic plant Eichornia crassipes and submerged plant Hydrilla verticillata were selected to investigate the effect of aquatic plant on quality of mild eutrophic water. The nutrient concentrations, phytoplankton chlorophyll a and other water quality physicochemical parameters in plant treatments and no plant treatment were determined during a five months indoor experiment. The results showed that the three plant treatments could significantly decrease the concentrations of nitrogen and phosphorus in the water column. The removal efficiency of total phosphorus was E.crassipes＞H.verticillata＞Z.latifolia, while the removal efficiency of total nitrogen was E.crassipes＞Z.latifolia＞H.verticillata. In addition, E.crassipes showed the strongest inhabiting effect on phytoplankton abundance; while Z.latifolia had the lowest effect on it. As compared with control group, H.verticillata increased the content of dissolved oxygen and pH and decreased the redox potential in the water, while E.crassipes had the opposite effect.Z.latifolia did not have a significant effect on water physicochemical parameters. These results could provide an insight in selection of plants for ecological restoration of mild eutrophic water bodies. [ABSTRACT FROM AUTHOR]

Despite the increase in sacred lotus (Nelumbo nucifera Gaertn.) recovered through archaeobotany at sites across China in recent years, little attention has been paid to the early history of human use of this aquatic plant. In this study, we collated and re-evaluated all published macro-botanical data of lotus in China for the period 9000–1100 BP. Our findings suggest that Neolithic rice farmers inhabiting the middle and lower Yangtze and Yellow River watersheds made extensive use of lotus roots and seeds as a supplementary starchy food. Furthermore, medicinal and cultural use of sacred lotus appears to have developed with the rise of China's urban aristocracy from the mid-Warring States to the Late Tang Dynasty period. Our study provides the foundation for a history of the Chinese people's long-term interaction with the sacred lotus plant. [ABSTRACT FROM AUTHOR]

The purification effect of a natural wetland landscape is often low when the focus is placed on the landscape effect. The effective combination of constructed wetland technology with landscape construction is challenging. Taking the Yuhe Wetland Park in Datong, Shanxi Province, China, as an example, the COD, phosphorus, and nitrogen removal capacities of aquatic plant species were determined, as well as the effects of the soil and the microbial communities. The highest COD and P removal capacity was observed for Typha orientalis Presl. which the purification rate reached 76.9% and 76.6%, and the highest N removal capacities were found for Scirpus validus Vahl., the rate of purification was 83.4%. Gram-negative bacteria were dominant. [ABSTRACT FROM AUTHOR]

In order to guide the salinization improvement and ecological restoration of wetlands in northwest China, the Taiyangshan wetland in Ningxia was used as the experimental area to study the salt tolerance of six kinds of plants such as Apium graveolens Linn, Karelinia caspia (Pall. ) Less, Lythrum salicaria L., Iris pseudacorus L., Iris lactea Pall. var. chinensis (Fisch. ) Koidz and Scirpus validus Vahl under different salinity levels by water culture experiment. The results showed that under the condition of 50% survival rate, the salt tolerance threshold of the six kinds of plants such as A. graveolens, K.caspia, Isalicaria,1.pseudacorus, Ilactea and S.validus were 3.30%,10.10%,4.30%,8.00%, 8.90% and 5.90%, respectively. The salt tolerance of the six kinds of plants was in the order of K.caspia, Ilactea,1.pseudacorus,S.validus,A. graveolens. In the highly saline and alkaline areas with salinity above 5.00%, K.caspia, I.pseudacorus, I.lactea and S.validus could be the first choice for ecological restoration. In the salinity 3.00%05.00‰ moderately saline area, Losalicaria and A.graveolens could also be used as the first choice. [ABSTRACT FROM AUTHOR]

With continuous global population growth, the challenges of expanding demand for sufficient and nutritious foods need to be addressed by exploring new and supplemental agricultural and food systems. Duckweed demonstrates a great potential for human food with many advantages. This review covers recent research on duckweed regarding plant cultivation, nutritional composition and quality, product development, and related safety issues and regulations for human food uses. Challenges and future research needs are discussed. Species and cultivation conditions have a significant effect on chemical and nutritional compositions of duckweed. Certain duckweed species contain high protein content (up to 45%) that provides all the essential amino acids meeting FAO references and can support human body growth and development. Duckweed also contains versatile carbohydrates including starch, cellulose, trace hemicellulose, and pectin that deliver functional properties and nutrients. In addition, duckweed is rich in minerals, vitamins, and phytochemicals, especially lutein and β-carotene which are positively associated with reduced risk of many chronic diseases. Duckweed could be used either in conventional cereal-based foods by partial substitution of wheat flour or for extraction of proteins and phytochemicals as functional ingredients. Studies are warranted for developing a duckweed supply chain and establishing duckweed as a novel staple food. [ABSTRACT FROM AUTHOR]

We report the first records of Bacopa egensis (Poepp.) Pennell from the Brazilian Northeast and the Cerrado domain. This species was collected in the municipality of Chapadinha, in eastern Maranhão state. Photographs, a map of occurrences in Brazil, a description, and comments on the morphology and taxonomy of B. egensis are provided, as well as an identification key to the Bacopa species of Maranhão. These new records are important due to the scarcity of collections of B. egensis from Brazil. The new data expand the longitudinal distribution of this species in the country and are an especially important contribution to the flora of Maranhão.

Aquatic plants play a key role in the structuring and functioning of shallow lake ecosystems. However, eutrophication often triggers shifts in plant communities and species diversity, especially in the early stages when the water is still clear. Additionally, water depth is an important factor regulating aquatic plant communities. We conducted a 50-day mesocosm study to investigate how water depth (50 cm and 100 cm) affected the functional traits (vertical expansion versus horizontal colonisation) of 20 aquatic plants under eutrophic clear-water conditions. Among the selected species, the submerged plants Hydrocotyle vulgaris and Limnophila indica exhibited higher plant height or biomass in deeper water, while the emergent plants Myriophyllum aquaticum showed the opposite trend. Additionally, Ludwigia peploides subsp. stipulacea exhibited better vertical growth than the remaining species, and the submerged species Vallisneria denseserrulata had better horizontal colonisation. There was a positive correlation between plant height and rhizome length, indicating the absence of a trade-off between vertical growth and horizontal expansion. Our findings suggest an overall resilience of aquatic plants to varying water depths within our study range and highlight the importance of analysing functional traits when selecting appropriate species in freshwater ecosystem restoration, particularly in the face of climate change-induced water depth fluctuations.

Using biomass to develop and obtain environmentally friendly and industrially applicable biomaterials is increasingly attracting global interest. Herein, cellulose nanocrystals (CNCs) and lignin nanoparticles (LNPs) were extracted from Lemna minor L., a freshwater free-floating aquatic species commonly called duckweed. To obtain CNCs and LNPs, two different procedures and biomass treatment processes based on bleaching or on the use of an ionic liquid composed of triethylammonium and sulfuric acid ([TEA][HSO4]), followed by acid hydrolysis, were carried out. Then, the effects of these treatments in terms of the thermal, morphological, and chemical properties of the CNCs and LNPs were assessed. The resulting nanostructured materials were characterized by using Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) spectroscopy, thermo-gravimetric analysis (TGA), and scanning electron microscopy (SEM). The results showed that the two methodologies applied resulted in both CNCs and LNPs. However, the bleaching-based treatment produced CNCs with a rod-like shape, length of 100–300 nm and width in the range of 10–30 nm, and higher purity than those obtained with ILs that were spherical in shape. In contrast, regarding lignin, IL made it possible to obtain spherical nanoparticles, as in the case of the other treatment, but they were characterized by higher purity and thermal stability. In conclusion, this research highlights the possibility of obtaining nanostructured biopolymers from an invasive aquatic species that is largely available in nature and how it is possible, by modifying experimental procedures, to obtain nanomaterials with different morphological, purity, and thermal resistance characteristics.

The combined morphological features of Stratiotes (Hydrocharitaceae) pollen, observed with light and electron microscopy, make it unique among all angiosperm pollen types and easy to identify. Unfortunately, the plant is (and most likely was) insect-pollinated and produces relatively few pollen grains per flower, contributing to its apparent absence in the paleopalynological record. Here, we present fossil Stratiotes pollen from the Eocene of Germany (Europe) and Kenya (Africa), representing the first reliable pre-Pleistocene pollen records of this genus worldwide and the only fossils of this family discovered so far in Africa. The fossil Stratiotes pollen grains are described and compared to pollen from a single modern species, Stratiotes aloides L. The paleophytogeographic significance and paleoecological aspects of these findings are discussed in relation to the Hydrocharitaceae fossil records and molecular phylogeny, as well as the present-day distribution patterns of its modern genera.

At present, the situation regarding heavy metal pollution in aquatic environments is becoming more and more serious. The bioaccumulation of heavy metals in aquatic plants causes obvious phytotoxicity, which can also induce secondary pollution in the aquatic environment. Zinc and copper, as indispensable elements for plant growth, are also prominent heavy metals in water pollution in China, and their concentrations play a crucial role in plant growth. In this study, we investigated the response of Pistia stratiotes (P. stratiotes) to different concentrations of Zn and Cu, and the results showed that plant growth and photosynthesis were inhibited under both Zn (1, 2, 4, and 8 mg/L) and Cu (0.2, 0.4, 0.8, and 1 mg/L) stresses. The relative growth rates of P. stratiotes under 8 mg/L Zn or 1 mg/L Cu stress were 6.33% and 6.90%, which were much lower than those in the control group (10.86%). Meanwhile, Zn and Cu stress caused insignificant change in the relative water contents of plants. The decrease in phlorophyll fluorescence parameters and chlorophyll contents suggested the significant photoinhibition of Zn and Cu stress. Chemical analysis of plant root exudates showed that the root secretion species obtained by gas chromatography–mass spectrometry (GC–MS) mainly included amino acids, alkanes, aldehydes, ketones, phenols, and more. Compared with the control group, the influence of Zn or Cu on the reduction in relative amounts of exudates was greater than that on the increase. The results of this study provide important data for the utilization of P. stratiotes in heavy metal-polluted water environments.

Organic matter was increased due to the input of plant litter, resulting in changes in the physicochemical properties and enhancement of greenhouse gas (GHG) emissions in water bodies. There are few reports on effects of decomposition of aquatic plants on GHGs emissions. This study investigated the effects of the degradation of two aquatic plants, Potamogeton crispus and Typha orientalis Presl, upon release of CO2 and CH4 at the sediment–water interface. During early decomposition, the release of CO2 and CH4 at the sediment–water interface was increased by the degradation of the two aquatic plants, and release flux of CO2 and CH4 were increased rapidly at first and then decreased. Due to the differences in properties of C, lignin, cellulose and other components of the plants, the Potamogeton crispus group obtained higher abundance of genes relevant to CO2 and CH4 metabolism, which leads to the increase of CO2 and CH4 emissions compared with that of the Typha orientalis Presl. In addition, dissolved oxygen and pH were decreased due to the decomposition of organic matter in the plant residues at the sediment–water interface, resulting in growth of anaerobic microorganisms. The increase of the relative abundance of anaerobic microorganisms promoted the decomposition of organic matter in the sediment and the enhancement of cell respiration, promoting the release of CH4 and CO2 during the decomposition of aquatic plants. [ABSTRACT FROM AUTHOR]

Seeds have morphoanatomical characteristics that determine the survival of plants in different environments, and these are directly related to phenomena such as dormancy. Natural selection filters the plant communities that inhabit the different ecosystems of planet earth and their seed banks. This has direct implications for ecological restoration. However, the seeds of aquatic plants have historically received much less attention than those of terrestrial ecosystems; and there is no history of morphoanatomical studies of seeds of aquatic vegetation for the Andes. In this research we studied the morphoanatomy of representative species of seed banks (SB), and floristic compositions of four Andean wetlands in a region with very high anthropic pressure such as the highland of eastern Antioquia. Results suggested that species with the highest abundances in the SB had seeds with morphophysiological dormancy and some had developed seeds with combined dormancy. The SB were dominated by mostly native aquatic plant species and emergent life forms that play an important role in the natural regeneration of these ecosystems. This study, in addition to being a pioneer in the investigation of the seeds of aquatic plants of the Andes, constitutes a guide for future studies for the design of ecological rehabilitation in wetlands that are under strong anthropic pressure. [ABSTRACT FROM AUTHOR]

Members of Didymellaceae have a wide geographical distribution throughout different ecosystems, and most species are associated with fruit, leaf, stem and root diseases of land plants. However, species that occur in aquatic plants are not clearly known. During a survey of the diversity of endophytes in aquatic plants in Yunnan, Sichuan, and Guizhou provinces, we obtained 51 isolates belonging to Didymellaceae based on internal transcribed spacer region (ITS) sequences. Further, the phylogenetic positions of these isolates were determined by combined sequences composed of ITS, partial large subunit nrRNA gene (28S nrDNA; LSU), RNA polymerase II second largest subunit (rpb2) and partial beta-tubulin gene (tub2). Combining morphological characteristics and multi-locus phylogenetic analyses, two new varieties belong to Boeremia and 12 new species distributed into seven genera were recognized from 51 isolates, i.e., Cumuliphoma, Didymella, Dimorphoma, Ectophoma, Leptosphaerulina, Remotididymella, and Stagonosporopsis. Among these species, only one species of Stagonosporopsis and two species of Leptosphaerulina show teleomorphic stages on OA, but have no anamorphic state. Each new species is described in detail, and the differences between new species and their phylogenetically related species are discussed here. The high frequency of new species indicates that aquatic plants may be a special ecological niche which highly promotes species differentiation. At the same time, the frequent occurrence of new species may indicate the need for extensive investigation of fungal resources in those aquatic environments where fungal diversity may be underestimated. [ABSTRACT FROM AUTHOR]

El Eneal wetland is a drinking water ecosystem located in the Gulf of Morrosquillo in the Colombian Caribbean. This is a very valuable water reserve for the area with environmental and ecological importance. As part of the project “Morphometric and hydrobiological evolution of La Ciénaga El Eneal: a strategic wetland for water supply, Sanguaré Reserve -San Onofre Sucre Colombia” which aims to compare the evolution of the wetland between 2004 and 2023. In the data collected for the month of July 2022, the presence of the carnivorous plant Utricularia sp. was found as a notable fact. which had not been reported to date in the Eneal wetland, San Onofre, Colombia, nor in the wetlands of this region. Upon finding the presence of submerged macrophytes Najas guadalupensis and the carnivorous plant Utricularia sp. It is inferred that the low primary productivity of this wetland may be related to these macrophytes and the presence of this plant that traps plankton and phytoplankton. [ABSTRACT FROM AUTHOR]

The study assess concentration of nine metals in the abiotic (water and sediment) and biotic components (aquatic plant and benthic Rita rita and benthopelagic Ctenopharyngodon idella fish) of River Ganga at Ganga Barrage, Kanpur. Amounts of all elements in river water and aquatic plant exceeded the permissible limit recommended by the world health organization and USEPA except for Zn in the aquatic plant. Heavy metals concentrations in critical organs (kidneys, liver, muscles and gills) of fish were estimated and health risk post consuming contaminated fishes from study area was evaluated through target hazard quotient and hazard index. The result revealed that the children were more prone to health risks than adult by consuming the fish. The geoaccumulation index (Igeo) values were contributed by Cu having value of 1.58 in water and 1.003 in sediments than their desired limit of one. Similarly, Cd also has value of 1.152 in water and Pb have the value above 2 in both water (2.172) and sediment (2.218) reflecting their main contribution in pollution of the Ganga river and its sediments. The contamination factor (CF) and ecological risk (Er) were due to Cd and Pb in Ganga River water and sediment respectively at Ganga Barrage, Kanpur. The pollution load index (PLI) and potential ecological risk index (PERI) values were within the safe levels of the abiotic community. [ABSTRACT FROM AUTHOR]

A protocol was standardized for large scale propagation through multiple shoot proliferation from the basal buds of Echinodorus argentinensis, an ornamental aquatic plant. Explants were treated for 15 minutes with commercial bleach (containing 0.825% Sodium hypochlorite as active ingredient) which was diluted with distilled water to a concentration of 15%; and were then dipped for a second in 100% ethanol to obtain axenic cultures. The axenic basal buds initiated shoot formation within a week when cultured on full strength Murashige & Skoog medium (MS medium) supplemented with 1.0 mg/l 6-Benzylaminopurine (BAP). Number of shoots produced per explant was maximum (2.5672 shoots per explant p< 0.05) on MS medium supplemented with 1.0 mg/l BAP. Shoots were elongated considerably in all the media tried for shoot multiplication and maximum elongation (2.87 cm, p< 0.05) of the in vitro developed shoots was observed on MS medium supplemented with 1.0 mg/l BAP in combination with 0.1 mg/l Naphthalene acetic acid (NAA). Root regeneration was observed on all the shoot regeneration media and the highest number of roots/shoot (3.4568 roots per shoot) was obtained on MS medium devoid of any kind of plant growth regulators. The plantlets developed in vitro were subjected to acclimatization procedure and were finally planted in the aquarium. The protocol is ready for commercialization. [ABSTRACT FROM AUTHOR]