Accumulation Capacity Research Articles

Accumulation Assessment of Mo4+, Pb++, and Cu++ in the Acidic Water of Copper Mines with Lemna minor and Lemna gibba

Pollutants accumulate in aquatic habitats due to mining activities. The duckweed family includes water plants such as Lemna gibba and Lemna minor, which are tiny, delicate, free-floating aquatic plants. L. minor and L. gibba were used in this study to examine the accumulation capacities of Mo4+, Pb++, and Cu++ in acidic fluids from copper mining. Two reactors were assigned to L. gibba and L. minor, respectively. These plants and the reactor water were gathered daily for 8 days. Acid mine water pH, temperature, and electric conductivity were also tested daily. L. gibba and L. minor were cleaned, dehydrated, and burned in a drying oven for a whole day at 300 °C. ICP-MS (inductively coupled plasma mass spectroscopy) was used to determine the Mo4+, Pb++, and Cu++ content of the plant and water samples. The Mo, Pb, and Cu concentrations in the copper mining acidic fluids were 30 ± 4, 260 ± 12, and 15,535 ± 322 μg L−1, respectively. Regarding Mo, Pb, and Cu extraction from copper mining acidic fluids, L. gibba and L. minor performed more efficiently than control samples, gathering 29 and 177 times more Mo, 30 and 109 times more Pb, and 495 and 1150 times more Cu, respectively. Considering these findings, L. gibba and L. minor are good plants for rehabilitating polluted waters and can efficiently remove Mo, Pb, and Cu from acid mine fluids.

OsEIN2-OsEIL1/2 pathway negatively regulates chilling tolerance by attenuating OsICE1 function in rice.

Low temperature severely affects rice development and yield. Ethylene signal is essential for plant development and stress response. Here, we reported that the OsEIN2-OsEIL1/2 pathway reduced OsICE1-dependent chilling tolerance in rice. The overexpressing plants of OsEIN2, OsEIL1 and OsEIL2 exhibited severe stress symptoms with excessive reactive oxygen species (ROS) accumulation under chilling, while the mutants (osein2 and oseil1) and OsEIL2-RNA interference plants (OsEIL2-Ri) showed the enhanced chilling tolerance. We validated that OsEIL1 and OsEIL2 could form a heterxodimer and synergistically repressed OsICE1 expression by binding to its promoter. The expression of OsICE1 target genes, ROS scavenging- and photosynthesis-related genes were downregulated by OsEIN2 and OsEIL1/2, which were activated by OsICE1, suggesting that OsEIN2-OsEIL1/2 pathway might mediate ROS accumulation and photosynthetic capacity under chilling by attenuating OsICE1 function. Moreover, the association analysis of the seedling chilling tolerance with the haplotype showed that the lower expression of OsEIL1 and OsEIL2 caused by natural variation might confer chilling tolerance on rice seedlings. Finally, we generated OsEIL2-edited rice with an enhanced chilling tolerance. Taken together, our findings reveal a possible mechanism integrating OsEIN2-OsEIL1/2 pathway with OsICE1-dependent cascade in regulating chilling tolerance, providing a practical strategy for breeding chilling-tolerant rice.

Single and combined phytoextraction of lead and cadmium on submerged plants Potamogeton pusillus L.: removal, bioaccumulation pattern, and phytotoxicity.

Under the present investigation, the submerged plant Potamogeton pusillus has been tested for the removal of lead (Pb) and cadmium (Cd). P. pusillus removal efficiency and accumulation capacity were examined in separated Pb and Cd solutions, at 0.5, 1.0, and 2mg L-1, and in solutions where both metals were present at the same concentration (0.5, 1.0, and 2mg L-1), under laboratory conditions for 3, 7, and 10days. Also, we examined the removal efficiency and accumulation capacity when a set of plants were exposed to 0.5mg L-1 of Pb (or Cd) and increasing concentrations (0.5, 1, and 2mg L-1) of Cd (or Pb) for 10days. The effect of Cd and Pb was assessed by measuring changes in the chlorophylls, carotenoids, and malondialdehyde contents. Results showed that P. pusillus could accumulate Cd and Pb from individual solutions. Roots and leaves accumulated the highest amount of Cd and Pb followed by the stems. Some phytotoxic effects were observed, especially at individual Cd exposures, but these effects were not observed in the two-metal system. The removal and accumulation of Pb by P. pusillus were significantly enhanced in the presence of Cd under certain conditions, presenting a good alternative for the removal of these metals from polluted aquifers. To the extent of our knowledge, this is the first report on both enhanced phytoextraction of Pb in the presence of Cd and bioaccumulation of these heavy metals by P. pusillus.

Mitigation of arsenic accumulation in crop plants using biofertilizer.

Elevated levels of arsenic in crop plants have been found in various regions worldwide, especially where agricultural soils have been affected by arsenic-enriched aquifers and human activities including mining, smelting, and pesticide application. Given the highly toxic nature of arsenic, remediation should be carried out immediately to reduce this potentially toxic element transport from soil to crop plants. This study focused on the utilization of biofertilizer which is a combination of arsenic-accumulating microorganisms and adsorbent (carrier) in order to achieve high efficiency of arsenic immobilization and ability to apply in the field. Thirty-two bacterial strains were isolated from 9 soil samples collected from the Dongjin and Duckum mining areas in Korea using a nutrient medium amended with 2 mM sodium arsenite. Among isolates, strain DE12 identified as Bacillus megaterium exhibited the greatest arsenic accumulation capacity (0.236 mg/g dry biomass) and ability to resist up to 18 mM arsenite. Among the three agricultural waste adsorbents studied, rice straw was proved to have a higher adsorption capacity (0.104 mg/g) than rice husk and corn husk. Therefore, rice straw was chosen to be the carrier to form biofertilizer together with strain DE12. Inoculation of biofertilizer in soil showed a reduction of arsenic content in the edible part of lettuce, water spinach, and sweet basil by 17.5%, 34.1%, and 34,1%, respectively compared to the control group. The use of biofertilizer may open up the potential application in the field for other food plants.

The influence of the hydropneumatic accumulator on the dynamic and noise of the hydrostatic drive operation

The article presents the possibility of influencing the hydrostatic drive's dynamics and noise using a hydropneumatics accumulator. The possibility of limiting the maximum dynamic load during the start-up period of a drive equipped with an accumulator and controlled by a slide distributor is presented in the article. The influence of the accumulator on the sound pressure level and its relationship with the maximum dynamic values of the working fluid pressure in the hydraulic system is also described. Experimental studies of the dynamics and acoustics of laboratory hydrostatic systems were performed. A dynamic model of the hydrostatic drive equipped with an accumulator was developed, which was used to perform simulation tests illustrating the impact of the accumulator capacity on the system's dynamics. Acoustic tests were carried out for a system with a linear hydrostatic drive simulator.

Evaluation of polyhydroxyalkanoate recovery from food waste by sequencing batch biofilm reactor with high mixed microbial biomass

In this study, the enrichment sequencing batch biofilm reactor (SBBR) and conventional enrichment reactor (SBR) were established, and a new strategy was developed to achieve higher biomass yield and polyhydroxyalkanoate (PHA) production from food waste than those achieved through the conventional method. After the 10th day of an expanded cultivation period, the respective active biomass concentrations in SBR and SBBR were 5.16 and 13.92 g/L, indicating a significant improvement in the biomass yield of mixed microbial culture in the SBBR. The PHA accumulation test revealed that maximum PHA concentration in SBR and SBBR reached 6.60 and 12.70 g/L, respectively, after 80 days of enrichment, indicating that compared to SBR, the SBBR could more effectively improve the PHA accumulation capacity. Meganema, Thauera, and Paracoccus were the dominant PHA-accumulating bacteria in the SBR and SBBR. Additionally, the volumetric productivity of the SBBR was 3.22 g COD/L/d, twice that of the SBR. This study provides new strategies and insights for improving PHA production and reducing the costs of PHA production and reactor investment.

Nano-radiopharmaceuticals as therapeutic agents.

In recent years, there has been an increased interest in exploring the potential synergy between nanotechnology and nuclear medicine. The application of radioactive isotopes, commonly referred to as radiopharmaceuticals, is recognized in nuclear medicine for diagnosing and treating various diseases. Unlike conventional pharmaceutical agents, radiopharmaceuticals are designed to work without any pharmacological impact on the body. Nevertheless, the radiation dosage employed in radiopharmaceuticals is often sufficiently high to elicit adverse effects associated with radiation exposure. Exploiting their capacity for selective accumulation on specific organ targets, radiopharmaceuticals have utility in treating diverse disorders. The incorporation of nanosystems may additionally augment the targeting capability of radiopharmaceuticals, leveraging their distinct pharmacokinetic characteristics. Conversely, radionuclides could be used in research to assess nanosystems pharmacologically. However, more investigation is needed to verify the safety and effectiveness of radiopharmaceutical applications mediated by nanosystems. The use of nano-radiopharmaceuticals as therapeutic agents to treat various illnesses and disorders is majorly covered in this review. The targeted approach to cancer therapy and various types of nanotools for nano-radiopharmaceutical delivery, is also covered in this article.

Herbaceous plants as heavy metals accumulators in conditions of ash and slag dumps

Storage of ash and slag waste causes a number of environmental problems, including the transformation of natural geochemical cycles and the change of the natural radioactive background due to the increased concentration of heavy metals and radioactive isotopes in coal combustion products. Plants can provide an effective approach for the analysis and monitoring of heavy metals contamination. Additionally, vegetation plays a significant role in the restoration and remediation of heavy metal-contaminated soils. The application of plants in phytoremediation is a green and sustainable solution for decontaminating polluted sites. Moreover, the key role in the restoration of contaminated sites belongs to native species. Within the presented research, the abilities of native dominant species to accumulate and tolerate heavy metals in conditions of ash and slag dumps were investigated on a limited number of samples. Primary analysis of the bioaccumulation of heavy metals through the bioaccumulation coefficient showed that zinc has the highest accumulation capacity in the studied species. The ability to bioaccumulate the analyzed heavy metals decreases in the following order: Zn > Fe > Cu > Mn > Cd > Ni > Pb. Indexing the biogeochemical activity of the tested species showed higher levels of biochemical activity for Anthemis arvensis L. than for Achillea millefolium L., however, these data need to be confirmed by statistical analysis. Determination of the translocation index of elements reflected the high mobility of zinc and cadmium with a high rate of transferring to above-ground biomass, but the potential for accumulation requires scaling up the experiment with the involvement of a larger number of samples and performing statistical data processing. Due to their ability to accumulate heavy metals in roots, plant species could be used for phytostabilization. Establishing methods of biomonitoring and the development of green reclamation technologies with native species application need further research with both selected species and other local species. The presented research showed primary results of bioindication and references for phytoremediation of heavy metal contamination of the ash and slag dumps, which is relevant for other similar environmental conditions.

Comparative transcriptome combined with physiological analyses revealed key genes and pathways for cadmium tolerance in wild-type and mutant microalgae Dunaliella salina

Cadmium (Cd) has become one of the major contaminants in aquatic ecosystems. The microalgae Dunaliella salina is known as a cadmium (Cd) accumulator and shows a high level of tolerance to Cd, but improved Cd tolerance and relevant mechanisms are still required for investigation. In this study, two mutant strains (M1 and M2) of D. salina with high Cd resistance were obtained by chemical mutagenesis. In the normal medium, there were no differences between the two mutant strains and the wild-type strain in biochemical and physiological indicators. However, the two mutant strains showed high Cd resistance, rapid growth rate, and good Cd accumulation capacity in the medium containing high levels of Cd compared with the wild strain, which may be involved in increases in protein content, accumulation of carotenoids and chlorophylls, and glutathione reductase (GR) activity. We identified 829, 587, and 740 differentially expressed genes (DEGs) from the Cd/Control, Cd + M1/Cd, and Cd + M2/Cd sample groups by transcriptome analysis, respectively. The main DEGs were found in the ribosome, DNA replication, photosynthesis-antenna, and photosynthesis pathways after KEGG enrichment. There were 39 DEGs involved in the photosynthesis and photosynthesis-antenna pathways, of which 28 DEGs were down-regulated by Cd in the wild-type strain but remained relatively unchanged in the mutant strains. Under Cd exposure, the mutant strains showed higher mRNA levels of most DEGs involved in the ribosome and DNA replication pathways than the wild strain. Taken together, the present study will help us understand the mechanism of Cd tolerance in microalgae, and provide candidate genes and key pathways for phytoremediation.

RNA-Seq Analysis Reveals the Molecular Mechanisms Regulating the Development of Different Adipose Tissues in Broiler Chicks.

In an effort to enhance growth rates, chicken breeders have undertaken intensive genetic selection. In the selection process, the primary aim is to accelerate growth, inadvertently leading to new chicken breeds having an increased capacity for rapid adipose tissue accumulation. However, little is known about the relationship between changes in gene expression and adipose tissue accumulation and deposition in chickens. Therefore, in this study, RNA-seq analysis was utilized, and transcriptome data were obtained from the abdominal fat, thoracic subcutaneous fat, and clavicular fat on day 1 (d1), day 4, day 7, day 11, and day 15 to reveal the molecular mechanisms regulating the development and deposition of different adipose tissues in broiler chicks. The results showed that the key period for adipocyte differentiation and proliferation was between d4 and d7 (abdominal fat development) and between d1 and d4 (chest subcutaneous fat and clavicular fat). In addition, candidate genes such as MYOG, S100A9, CIDEC, THRSP, CXCL13, and NMU related to adipose tissue growth and development were identified. Further, genes (HOXC9, AGT, TMEM182, ANGPTL3, CRP, and DSG2) associated with the distribution of adipose tissue were identified, and genes (MN1, ANK2, and CAP2) related to adipose tissue growth were also identified. Taken together, the results from this study provide the basis for future studies on the mechanisms regulating adipose tissue development in chickens. Further, the candidate genes identified could be used in the selection process.

Transcriptome Profiling of a Salt Excluder Hybrid Grapevine Rootstock ‘Ruggeri’ throughout Salinity

Salinity is one of the substantial threats to plant productivity and could be escorted by other stresses such as heat and drought. It impairs critical biological processes, such as photosynthesis, energy, and water/nutrient acquisition, ultimately leading to cell death when stress intensity becomes uncured. Therefore, plants deploy several proper processes to overcome such hostile circumstances. Grapevine is one of the most important crops worldwide that is relatively salt-tolerant and preferentially cultivated in hot and semi-arid areas. One of the most applicable strategies for sustainable viticulture is using salt-tolerant rootstock such as Ruggeri (RUG). The rootstock showed efficient capacity of photosynthesis, ROS detoxification, and carbohydrate accumulation under salinity. The current study utilized the transcriptome profiling approach to identify the molecular events of RUG throughout a regime of salt stress followed by a recovery procedure. The data showed progressive changes in the transcriptome profiling throughout salinity, underpinning the involvement of a large number of genes in transcriptional reprogramming during stress. Our results established a considerable enrichment of the biological process GO-terms related to salinity adaptation, such as signaling, hormones, photosynthesis, carbohydrates, and ROS homeostasis. Among the battery of molecular/cellular responses launched upon salinity, ROS homeostasis plays the central role of salt adaptation.

Geomorphological changes and sediment carbon accumulation at the bare mudflat-saltmarsh interface: The role of typhoons

Blue carbon stored in coastal wetlands can be highly impacted by extreme events, such as typhoons. However, the sediment carbon accumulation capacity in this circumstance, remains unclear. In this study, a field site crossing the bare mudflat-saltmarsh interface was established in Southern Hangzhou Bay, to investigate the geomorphological and subsequent sediment carbon accumulation changes during the typhoon season (2 months) and the succeeding calm weather period (10 months). Surface Elevation Tables (SETs) were used, together with GPS-RTK and UAV-LiDAR surveys, to observe surface elevation changes at different spatial scales. The elevation and sediment organic carbon density data were used to estimate the gain/loss of sediment carbon pool under the impact of two successive typhoons, “In-Fa” and “Chanthu”. This revealed that during the typhoon season, 6.3 cm of surface erosion occurred on the bare mudflat whilst rapid depositions of 6.1 and 12.3 cm occurred in Scirpus mariqueter and Spartina alterniflora habitats, respectively. In the gap between the two typhoon events, the bare mudflat experienced deposition of 4.2 cm, signalling recovery from erosion, but deposition within the saltmarsh front slowed. During the calm weather period, sediment deposition increased landward, with magnitudes of 13.1 cm, 16.4 cm, and 18.2 cm. Sediment carbon budget estimates indicated that during the typhoon season, the bare mudflat lost ~3.4 Mg C ha−1 but saltmarshes gained ~4.9 Mg C ha−1 in their sediment organic carbon pools. These changes in sediment carbon accumulation rates over the typhoon season accounted for >30 % of annual change in the study area, and may be associated with tidal creek dynamics. This study suggests the important role of typhoons in mediating the sediment carbon pool across the mudflat-saltmarsh interface. With future climate change, increasingly frequent catastrophic events could cause considerable changes in coastal blue carbon sequestration capacity.

Serpentine environment prevails over geographic distribution in shaping the genetic diversity of Medicago lupulina L.

Edaphic conditions of serpentine soils, naturally rich in heavy metals, act as a strong selection pressure that shapes specific metal-tolerant ecotypes. Medicago lupulina L. (black medick) is not only a widespread plant species that prefers calcareous and dry soil types but also grows at the borders of serpentine formations. It can also be found in waste and disturbed habitats. This is a species with reported phytoremediation potential, however, there is no published data regarding the impact of the environment on the genetic distribution of this species. The aim of our research was to explore how selection pressure of serpentine soils affects genetic diversity of M. lupulina and to test heavy-metal accumulation capacity of this species. Specimens of 11M. lupulina populations were collected from serpentine outcrops located in Central and Eastern Bosnia as well as from non-serpentine sites. Soil and plant samples were analyzed for the total contents of heavy metals using air-acetylene flame atomic absorption spectroscopy. Genetic diversity was analyzed using AFLP (Amplified Fragment Length Polymorphism) markers. Serpentine soils showed high nickel, cobalt, chromium and iron concentrations. Nickel and manganese concentrations in soil samples and plant material showed statistically significant correlation. Although plants in two populations show the ability to extract Ni, M. lupulina does not show hyperaccumulating properties. Despite severe selective pressure, genetic diversity in serpentine populations is not reduced. Analyses of intrapopulation and interpopulation genetic diversity showed significant genetic differentiation among populations which is not related to their geographic distance. Population from non-metalliferous soil showed clear separation from all other populations. Diversity data suggest that serpentine populations maintain genetic diversity by undetected mechanisms and that edaphic factors rather than geography influence genetic structure analyzed M. lupulina populations.

Assessment of sulfamethoxazole removal by three wetland plant species under hydroponic conditions: uptake, accumulation, and physiological responses

Plants play a crucial role as a removal pathway in constructed wetlands, demonstrating the ability to absorb and tolerate antibiotics from wastewater. However, the specific contribution of plants in this regard has not yet to be sufficiently established. To gain a more comprehensive insight into the associated processes, we selected three common wetland plant species, Canna indica L. (C. indica), Cyperus alternifolius L. (C. alternifolius), and Thalia dealbata Fraser (T. dealbata), to evaluate their capacity for uptake, accumulation, and physiological response in the removal of sulfamethoxazole (SMX) at varying initial concentrations (10, 30, 100, and 300 µg/L) under hydroponic conditions. The results showed that SMX removal was more efficient at lower concentrations (10 and 30 µg/L) than at higher concentrations (100 and 300 µg/L). Moreover, plant systems were found to consistently outperform unplanted systems in SMX removal. Among the assessed species, C. indica was identified as being relatively effective in the removal of SMX, whereas the performance of C. alternifolius was notably less pronounced. A positive correlation was observed between the concentration of SMX in the plant tissues and that in the external aqueous medium. However, plant tissue residues contributed only a minor fraction to the overall removal of SMX. Wetland plants absorb SMX through their roots, and we accordingly detected significantly higher concentrations in submerged plant tissues. Furthermore, we also detected reductions in net photosynthetic rates indicative of potential phytotoxicity, which is associated with the accumulation of antibiotic in the shoot tissues. Accumulation of SMX in the roots and rhizomes was also found to be associated with the development of shorter roots, with this effect becoming more pronounced with an increase in the concentration of exogenous SMX. However, despite these adverse effects, plants can detoxify antibiotics via the glutathione pathway. Of the assessed plant species, C. indica was identified as the most SMX tolerant, as indicated by K m and V max values, with C. alternifolius being the least tolerant. Our findings in this study reveal the potential value of wetland plants in the sequestration of antibiotics and provide evidence for the underlying mechanisms of action. These findings could make an important contribution to the implementation of phytoremediation in antibiotic-contaminated water.

Temporal and Within-Sporophyte Variations in Triphenyltin Chloride (TPTCL) and Its Degradation Products in Cultivated Undaria pinnatifida

Undaria pinnatifida can effectively deal with organotin pollution through its excellent accumulation and degradation capabilities found under laboratory conditions. However, nothing is known regarding its accumulation, degradation performance, and related impact factors in the wild farming area. In this study, we monitored triphenyltin chloride (TPTCL) contents and degradation products in different algal parts (blades, stipes, sporophylls, and holdfasts) of cultivated U. pinnatifida from December 2018 to May 2019. Our results showed that sporophytes had an accumulation and degradation capacity for TPTCL. The TPTCL contents and degradation products varied with the algal growth stages and algal parts. TPTCL accumulated in the blades at the growth stage and the blades, stipes, sporophylls, and holdfasts at the mature stage. The TPTCL content among algal parts was blades (74.92 ± 2.52 μg kg−1) > holdfasts (62.59 ± 1.42 μg kg−1) > sporophylls (47.24 ± 1.41 μg kg−1) > stipes (35.53 ± 0.55 μg kg−1). The primary degradation product DPTCL accumulated only in the blades at any stage, with a concentration of 69.30 ± 3.89 μg kg−1. The secondary degradation product MPTCL accumulated in the blades at the growth stage and in the blades, stipe, and sporophyll at the mature stage. The MPTCL content among algal parts was blades (52.80 ± 3.48 μg kg−1) > sporophylls (31.08 ± 1.53 μg kg−1) > stipes (20.44 ± 0.85 μg kg−1). The accumulation pattern of TPTCL and its degradation products seems closely related to nutrient allocation in U. pinnatifida. These results provide the basis for applying cultivated U. pinnatifida in the bioremediation of organotin pollution and the food safety evaluation of edible algae.

Soil Cd increased the leaf litter Cd remains of Solanum nigrum and Solanum lycopersicum

Plant litter decomposition is a natural pathway of heavy metal cycling in soil ecosystems, but the dynamics of heavy metal release during litter decomposition are relatively poorly understood. The purpose of this study was to investigate the effects of species, soil fauna and soil Cd addition on litter decomposition and Cd release dynamics. Therefore, we selected two plants, Solanum nigrum and S. lycopersicum with large differences in Cd accumulation capacity. First, they were enriched with Cd during the growing period and leaf litter was harvested after 6 months of pretreatment. Then, the decomposition of leaf litter was conducted with or without soil Cd and Eisenia fetida through lab pot tests. Our results showed that leaf litter Cd led to a significant decrease in litter decomposition rate (K value), with a maximum decrease of 32.1% in S. nigrum and 30.1% in S. lycopersicum. We observed that the presence of E. fetida significantly increased K value, but the effect was similar in the +leaf Cd treatment and the -leaf Cd treatment, both for S. nigrum and S. lycopersicum. Interestingly, the litter Cd concentration did not decrease during decomposition, but showed an increasing trend, especially for S. nigrum in the +soil Cd treatment. Moreover, the litter Cd remains was higher in the +soil Cd treatment compared to the -soil Cd treatment for both S. nigrum and S. lycopersicum, no matter whether with or without E. fetida. This result suggests that the Cd may be transferred from soil to litter, thus increasing the litter Cd remains. Overall, our study shows that leaf litter Cd slowed down the carbon cycling in ecosystems. In addition, the release of litter Cd has a lag, and the litter has a certain adsorption capacity for soil Cd, which intensifies the harm to the ecology during litter transfer.

Potassium transporter OsHAK17 may contribute to saline-alkaline tolerant mechanisms in rice (Oryza sativa).

Rice production is seriously affected by saline-alkaline stress worldwide. To elucidate the saline-alkaline tolerance mechanisms in a novel tolerant rice variety, Shwe Nang Gyi (SNG), we investigated ion accumulation in SNG and Koshihikari (KSH), which is a saline-alkaline sensitive rice variety, and the candidates for saline-alkaline inducible genes in SNG using RNA-seq. SNG had superior ion accumulation capacity, such as K and Zn, compared to KSH. In contrast, SNG accumulated the same level of Na content in its leaf blades as KSH despite the higher dry weight of the SNG leaf blades. We further found that the expression of numerous genes, including several K+ transporter/high-affinity K+ transporter/K+ uptake protein/K+ transporter (HAK/KUP/KT) family members, were upregulated in SNG, and that OsHAK17 and OsHAK21 expression levels in the roots were significantly higher in SNG than in KSH. Moreover, yeast complementation analysis revealed that OsHAK17 was involved in K+ uptake under high-Na conditions. These results suggested that SNG has an effective K+ acquisition system supported by OsHAK17 functioning in saline-alkaline environments.

Greenery planning for urban air pollution control based on biomonitoring potential: Explicit emphasis on foliar accumulation of particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs)

In this study, efficiencies of eight indigenous plants of Baishnabghata Patuli Township (BPT), southeast Kolkata, India, were explored as green barrier species and potentials of plant leaves were exploited for biomonitoring of particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs). The present work focused on studying PM capturing abilities (539.32−2766.27 μg cm−2) of plants (T. divaricata, N. oleander and B. acuminata being the most efficient species in retaining PM) along with the estimation of foliar contents of PM adhered to leaf surfaces (total sPM (large + coarse): 526.59−2731.76 μg cm−2) and embedded within waxes (total wPM (large + coarse): 8.73−34.51 μg cm−2). SEM imaging used to analyse leaf surfaces affirmed the presence of innate corrugated microstructures as main drivers for particle capture. Accumulation capacities of PAHs of vehicular origin (total index, TI > 4) were compared among the species based on measured concentrations (159.92−393.01 μg g−1) which indicated T. divaricata, P. alba and N. cadamba as highest PAHs accumulators. Specific leaf area (SLA) of plants (71.01−376.79 cm2 g−1), a measure of canopy−atmosphere interface, had great relevance in PAHs diffusion. Relative contribution (>90%) of 4–6 ring PAHs to total carcinogenic equivalent and potential as well as 5−6 ring PAHs to total mutagenic equivalent and potential had also been viewed with respect to benzo[a]pyrene. In−depth analysis of foliar traits and adoption of plant−based ranking strategies (air pollution tolerance index (APTI) and anticipated performance index (API)) provided a rationale for green belting. Each of the naturally selected plant species showed evidences of adaptations during abiotic stress to maximize survival and filtering effects for reductive elimination of ambient PM and PAHs, allowing holistic management of green spaces.

Brassinosteroid decreases cadmium accumulation via regulating gibberellic acid accumulation and Cd fixation capacity of root cell wall in rice (Oryza sativa)

The precise mechanism behind the association between plants' reactions to cadmium (Cd) stress and brassinosteroid (BR) remains unclear. In the current investigation, Cd stress quickly increased the endogenous BR concentration in the rice roots. Exogenous BR also increased the hemicellulose level in the root cell wall, which in turn increased its capacity to bind Cd. Simultaneously, the transcription level of genes responsible for root Cd absorption was decreased, including Natural Resistance-Associated Macrophage Protein 1/5 (OsNRAMP1/5) and a major facilitator superfamily gene called OsCd1. Ultimately, the increased expression of Heavy Metal ATPase 3 (OsHMA3) and the decreased expression of OsHMA2, which was in charge of separating Cd into vacuoles and translocating Cd to the shoots, respectively, led to a decrease in the amount of Cd that accumulated in the rice shoots. In contrast, transgenic rice lines overexpressing OsGSK2 (a negative regulator in BR signaling) accumulated more Cd, while OsGSK2 RNA interference (RNAi) rice line accumulated less Cd. Furthermore, BR increased endogenous Gibberellic acid (GA) level, and applying GA could replicate its alleviative effect. Taken together, BR decreased Cd accumulation in rice by mediating the cell wall’s fixation capacity to Cd, which might relied on the buildup of the GA.

Accumulation characteristics of liquid crystal monomers in plants: A multidimensional analysis

Liquid crystal monomers (LCMs), identified as emerging contaminations, have been detected in soils and plants, but their accumulation characteristics in plants haven’t been studied. Therefore, this study systematically investigated the accumulation characteristics of LCMs in plants from four dimensions (i.e., plant fruit species, soil types, plant growth stages, and LCMs categories) for the first time. The LCMs concentrations (9.96 × 10−4 to 114.608 ng/g) in 22 plant fruits were predicted by the partition-limited model. Grains with the highest lipid content showed the highest LCMs accumulation propensity. Plants grown in paddy soil showed a strong LCMs accumulation capacity. Results showed that the LCMs accumulation capacity in plants from soils decreased when the soil organic matter content increased. A preferential accumulation of LCMs in plant root systems during growth was found by the molecular dynamics simulations. Compared to polychlorinated biphenyls (as the reference contaminants of LCMs), LCMs exhibit higher accumulation in plant roots and lower translocation to shoots. For the fourth dimension, lipophilicity was found to be the main reason of LCMs accumulation by intergraded stepwise linear regression with sensitivity analysis. This is the inaugural research concentrating on LCMs accumulation in plants, providing insights and theoretical guidance for future LCMs management strategies multidimensionally.