Concentrations In Plant Tissues Research Articles

Iodine Biofortification and Seaweed Extract-Based Biostimulant Supply Interactively Drive the Yield, Quality, and Functional Traits in Strawberry Fruits.

The horticultural sector is seeking innovative and sustainable agronomic practices which could lead to enhanced yield and product quality. Currently, plant biofortification is recognized as a valuable technique to improve microelement concentrations in plant tissues. Among trace elements, iodine (I) is an essential microelement for human nutrition. Concomitantly, the application of biostimulants may improve overall plant production and quality traits. With the above background in mind, an experiment was designed with the aim of assessing the interactive impact of a seaweed extract-based biostimulant (SwE) (0 mL L-1 (served as control) or 3 mL L-1 (optimal dosage)) and 0, 100, 300, or 600 mg L-1 I on the growth parameters, yield, fruit quality, minerals, and functional characteristics of the tunnel-grown "Savana" strawberry. SwE foliar application improved the plant growth-related traits, total and marketable yield, fruit color parameters, soluble solids content, nitrogen (N), potassium (K), and magnesium (Mg) fruit concentrations. Furthermore, an enhancement in the fruit dry matter content, ascorbic acid, and I concentration in fruits was detected when the SwE supply interacted with a mild I dose (100 or 300 mg L-1). The research underlined that combining SwE application and I biofortification increased the strawberry yield and quality and enhanced the plant nutritional status variation, thereby, determining a boosted strawberry I tolerance.

Natural products of pentacyclic triterpenoids: from discovery to heterologous biosynthesis.

Covering: up to 2022Pentacyclic triterpenoids are important natural bioactive substances that are widely present in plants and fungi. They have significant medicinal efficacy, play an important role in reducing blood glucose and protecting the liver, and have anti-inflammatory, anti-oxidation, anti-fatigue, anti-viral, and anti-cancer activities. Pentacyclic triterpenoids are derived from the isoprenoid biosynthetic pathway, which generates common precursors of triterpenes and steroids, followed by cyclization with oxidosqualene cyclases (OSCs) and decoration via cytochrome P450 monooxygenases (CYP450s) and glycosyltransferases (GTs). Many biosynthetic pathways of triterpenoid saponins have been elucidated by studying their metabolic regulation network through the use of multiomics and identifying their functional genes. Unfortunately, natural resources of pentacyclic triterpenoids are limited due to their low content in plant tissues and the long growth cycle of plants. Based on the understanding of their biosynthetic pathway and transcriptional regulation, plant bioreactors and microbial cell factories are emerging as alternative means for the synthesis of desired triterpenoid saponins. The rapid development of synthetic biology, metabolic engineering, and fermentation technology has broadened channels for the accumulation of pentacyclic triterpenoid saponins. In this review, we summarize the classification, distribution, structural characteristics, and bioactivity of pentacyclic triterpenoids. We further discuss the biosynthetic pathways of pentacyclic triterpenoids and involved transcriptional regulation. Moreover, the recent progress and characteristics of heterologous biosynthesis in plants and microbial cell factories are discussed comparatively. Finally, we propose potential strategies to improve the accumulation of triterpenoid saponins, thereby providing a guide for their future biomanufacturing.

Dendroremediation Potential of Six Quercus Species to Polluted Soil in Historic Copper Mining Sites

Green remediation of severely contaminated soils around mining sites can be achieved using suitable woody plants such as Quercus species, but their phytoremediation potential has not been well evaluated yet. Six Quercus species, which were popular in ecological restoration and landscape application in east China, were selected and evaluated for their phytoremediation potential of metal polluted soil using a pot experiment that lasted for 150 d. The results suggested that Quercus species exhibited high tolerance to multi-metal contamination of Cu (9839 mg·kg−1), Cd (8.5 mg·kg−1), and Zn (562 mg·kg−1) with a tolerance index (TI) ranging from 0.52 to 1.21. Three Quercus (Q. pagoda, Q. acutissima, and Q. nuttallii) showed relatively higher tolerance with TIs of 1.08, 1.09, and 1.21, respectively. Above-ground tissues accounted for most of the total biomass in T1 (mixture of clean and polluted soil, 50%) and T2 (100% polluted soil) treatments for most species. The Cu contents in plant tissues were in the order of root > leaf > stem, whereas Zn exhibited the order of leaf > stem > root, and Cd showed divergent mobility within the Quercus species. All the Quercus species exhibited higher capacity for Zn phytoextraction with translocation factor (TF) over 1 and Cu/Cd phytostabilization with TFs lower than 1. The analytic hierarchy process-entropy weight model indicated that Q. virginiana and Q. acutissima were two excellent species with evident phytoremediation capacity of Cu, Cd, and Zn co-contaminated soil. Taken together, Quercus species showed great potential for phytoremediation of soils severely polluted by Cu, Cd, and Zn around historic mining sites. Application of Quercus species is a green remediation option with low-maintenance cost and prospective economic benefit for phytomanagement of historic mining sites.

Water Deficit-Induced Changes in Phenolic Acid Content in Maize Leaves Is Associated with Altered Expression of Cinnamate 4-Hydroxylase and p-Coumaric Acid 3-Hydroxylase

The amino acid phenylalanine is a precursor to phenolic acids that constitute the lignin biosynthetic pathway. Although there is evidence of a role of some phenolic acids in plant responses to pathogens and salinity, characterization of the involvement of phenolic acids in plant responses to drought is limited. Drought reduces water content in plant tissue and can lead to decreased cell viability and increased cell death. We thus subjected maize seedlings to water deficit and evaluated relative water content and cell viability together with p-coumaric acid, caffeic acid and ferulic acid contents in the leaves. Furthermore, we measured the enzymatic activity of cinnamate 4-hydroxylase (EC 1.14.13.11) and p-coumarate 3-hydroxylase (EC 1.14.17.2) and associated these with the expression of genes encoding cinnamate 4-hydroxylase and p-coumarate-3 hydroxylase in response to water deficit. Water deficit reduced relative water content and cell viability in maize leaves. This corresponded with decreased p-coumaric acid but increased caffeic and ferulic acid content in the leaves. Changes in the phenolic acid content of the maize leaves were associated with increased enzymatic activities of cinnamate 4-hydroxylase and p-coumarate hydroxylase. The increased enzymatic activity of p-coumarate 3-hydroxylase was associated with increased expression of a gene encoding p-coumarate 3-hydroxylase. We thus conclude that metabolic pathways involving phenolic acids may contribute to the regulation of drought responses in maize, and we propose that further work to elucidate this regulation may contribute to the development of new maize varieties with improved drought tolerance. This can be achieved by marker-assisted selection to select maize lines with high levels of expression of genes encoding cinnamate 4-hydroxylase and/or p-coumarate 3-hydroxylase for use in breeding programs aimed and improving drought tolerance, or by overexpression of these genes via genetic engineering to confer drought tolerance.

Computer aided detection of nitrogen content in plant tissues using convolutional neural network

Computer aided detection of nitrogen content in plant tissues using convolutional neural network

Study of the Phytoextraction and Phytodegradation of Sulfamethoxazole and Trimethoprim from Water by Limnobium laevigatum

Phytoremediation is an environmentally friendly and economical method for removing organic contaminants from water. The purpose of the present study was to use Limnobium laevigatum for the phytoremediation of water from sulfamethoxazole (SMX) and trimethoprim (TRI) residues. The experiment was conducted for 14 days, in which the loss of the pharmaceuticals in water and their concentration in plant tissues was monitored. Determination of SMX and TRI was conducted using liquid chromatography coupled with tandem mass spectrometry. The results revealed that various factors affected the removal of the contaminants from water, and their bioaccumulation coefficients were obtained. Additionally, the transformation products of SMX and TRI were identified. The observed decrease in SMX and TRI content after 14 days was 96.0% and 75.4% in water, respectively. SMX removal mainly involved photolysis and hydrolysis processes, whereas TRI was mostly absorbed by the plant. Bioaccumulation coefficients of the freeze-dried plant were in the range of 0.043-0.147 for SMX and 2.369-2.588 for TRI. Nine and six transformation products related to SMX and TRI, respectively, were identified in water and plant tissues. The detected transformation products stemmed from metabolic transformations and photolysis of the parent compounds.

Response of Nutritional Status and Tea Quality to the Rate and Substitution of Chemical Fertilizers with Organic Manure

Proper fertilization is important to sustainable tea production. A field experiment was conducted to investigate the response of quality components in a chlorotic tea variety (Zhonghuang-2) to rates of fertilizers and the substitution ratio of chemical fertilizers by organic manure based on rapeseed cake. Chlorotic tea varieties have unique metabolic characteristics and produce superior tea containing high contents of free amino acids. Results showed that fertilization significantly increased yield and contents of free amino acid (TFAA) but reduced contents of total polyphenol (TP) and the ratio of TP/TFAA. Contents of TFAA and TP and the TP/TFAA ratio were closely related to nitrogen (N) concentrations in plant tissues in response to the rate of N fertilizers. The results suggest that the quality-related components in the chlorotic tea variety respond to fertilizers in a similar way as normal tea varieties. The optimal rates of N, phosphorus (P), and potassium fertilizers were discussed and recommended based on the response of quality components of tea and the contents of nutrients in plants and soil. The full substitution of chemical fertilizers by organic manure showed no special benefit on tea quality and had lower N and P agronomic use efficiency due to a low bioavailability of nutrients. The partial substitution of chemical fertilizers by organic manure significantly improved tea yield, quality, profit, and economic and environmental sustainability.

Cardamine violifolia as a potential Hg hyperaccumulator and the cellular responses

Cardamine violifolia belongs to the Brassicaceae family and is a selenium (Se) hyperaccumulator found in Enshi, China. In this study, C. violifolia was found to accumulate mercury (Hg) in its roots and aboveground parts at concentrations up to 6000 μg/g. In the seedling and mature stages, the bioaccumulation factors (BAFS) of Hg reached 1.8–223, while the translocation factor (TF) for Hg reached 1.5. We observed a significant positive correlation between THg concentrations in plant tissues and those in the soil (r2 = 0.71–0.84). Synchrotron radiation X-ray fluorescence with focused X-ray (μ-SRXRF) showed that Hg was translocated from the roots to shoots through the vascular bundle and was transported through the leaf veins in leaves. Transmission electron microscopy showed that root cells were more tolerant to Hg than leaf cells. These findings provide insights into the mechanisms of Hg hyperaccumulation in C. violifolia. Overall, we demonstrated that C. violifolia is a promising Hg hyperaccumulator that may be used for phytoremediating Hg-contaminated farmlands.

Use of Soil Ameliorant And Inorganic Fertilizer to Increase Soil Fertility Phosphorous Concentrations in Plant Tissue, Growth and Yield of Shallot in Dry Land

Sub-optimal land use including dry land in West Nusa Tenggara (NTB) has not been optimal due to various land biophysical constraints such as low soil fertility, physical conditions with rough soil texture, and uncertain water availability, so efforts are needed to improve the land condition. . Shallots (Allium ascalonicum L.) is one of the vegetables that have a high enough potential to be developed in the land. The purpose of this study was to determine the interaction of various soil enhancers and doses of inorganic fertilizers on growth, tuber yield, and P content of shallot plants in suboptimal land. The method used in this research is the experimental method. The experimental design used was a Randomized Block Design which was arranged in a factorial design consisting of two factors. The first factor is a soil amendment, consisting of 4 types, namely: P0= without soil ameliorant; P1= 20 tons ha-1 manure; P2= 5 tons ha-1 biochar; P3= 10 tons ha-1 mushroom baglog waste. The second factor was the dose of NPK fertilizer, consisting of N1=150 kg ha-1; N2 = 300 kg ha-1; N3=450 kg ha-1. Each treatment combination was repeated 3 times. The results showed that there was an interaction between soil amendments and the dose of NPK fertilizer on organic C and soil CEC. But there was no interaction between the growth and yield of shallot bulbs. Soil ameliorant and dose of NPK fertilizer alone affected growth, namely the height and number of leaves of shallot plants. The best treatment for tuber yield was obtained in a combination of an application of 20 tons ha-1 of manure and 450 kg ha-1 of NPK fertilizer. Likewise with the P concentration in the onion plant tissue.

Nutritional enrichment of tomato (Lycopersicon esculentum L.) through Zinc (Zn) and Boron (B) Fertilization

The influence of micronutrients namely zinc (Zn) and boron (B) with or without farmyard manure (FYM) on growth, yield and quality parameters viz. ascorbic acid and carotene content of tomato was evaluated. A field experiment was conducted with graded doses of Zn (soil and soil + foliar application) and B (soil application) application with or without FYM for the two consecutive years (2012 and 2013). Results revealed that application of Zn and B significantly enhanced fruit yield and different growth parameters as well as plant tissue concentration of Zn and B in tomato. The highest increase in fruit yield over control (27.6%) was observed with the conjoint application of Zn (soil + foliar), B (2.0 kg ha−1) and FYM. Soil application of Zn at higher doses (10 kg ha−1) as well as its application through both soil + foliar method has an edge over control or its application at comparatively lower doses in increasing the fruit yield of tomato. Results further revealed that combined application of Zn and B can significantly increase the important quality parameters viz. carotene and ascorbic acid content in tomato. Such increase in carotene content to the tune of 25 and 35% and ascorbic acid content to the tune of 7 and 30% over control were observed with soil + foliar application of Zn and 2 kg ha−1 B, respectively. Therefore, optimization of Zn and B doses can improve the yield and quality of tomato as well as helps in correcting the micronutrients malnutrition vis-à-vis nutritional disorders in humans by enriching the antioxidants.

Application of biochar and compost improved soil properties and enhanced plant growth in a Pb-Zn mine tailings soil.

This study evaluated the effect of biochar and compost on physiochemical properties, heavy metal content, microbial biomass, enzyme activities, and plant growth in Pb-Zn mine tailings. In this study, a pot experiment was conducted to evaluate the effects of biochar, compost, and their combination on the availability of heavy metals, physicochemical features, and enzyme activities in mining soil. Compared to separate addition, the combined application of biochar and compost was more effective to improve soil pH, soil organic carbon (SOC), total nitrogen (TN), available phosphorus (AP), and potassium (AK). All amendments significantly decreased CaCl2-extractable Pb, Zn, Cu, and Cd. Soil enzyme activities were activated by biochar and compost. Meanwhile, the addition of biochar and compost decreased heavy metal content in plant tissues and increased plant biomass. Pearson's correlation analysis showed that plant biomass was positively correlated with nutrient levels, microbial biomass, and enzyme activities, whereas it was negatively correlated with CaCl2-extractable heavy metals. These results enhance our understanding of the ecological functions of biochar and compost on the restoration of mining soil and reveal the potential benefit of organic amendments on the improvement of mining soil quality.

Citrus Huanglongbing correlated with incidence of Diaphorina citri carrying Candidatus Liberibacter asiaticus and citrus phyllosphere microbiome.

In China, citrus Huanglongbing (HLB) disease is caused by the Candidatus Liberibacter asiaticus bacterium, which is carried by the Asian citrus psyllid Diaphorina citri Kuwayama. It was hypothesized that the epidemic of the HLB may related with the rate of bacterium presence in the insect vector and bacterium content in plant tissues, as well as the phyllosphere microbe communities changes. This study systematically analyzed the presence or absence of Ca. L. asiaticus in citrus tree leaves and in the insect vector D. citri over a 6-year period using real-time PCR. In addition, changes in the number of bacteria carried by D. citri over 12 months were quantified, as well as the relationship between the proportion of D. citri carrying Ca. L. asiaticus and the proportion of plants infected with Ca. L. asiaticus were analyzed. Results showed that the proportion of D. citri carrying bacteria was stable and relatively low from January to September. The bacteria in citrus leaves relatively low in spring and summer, then peaked in December. The proportion of D. citri carrying bacteria gradually declined from 2014 to 2019. The proportion of D. citri carrying Ca. L. asiaticus showed a significant positive correlation with the proportion of diseased citrus. The phyllosphere bacterial and fungal communities on the healthy citrus leaf were significantly different with the disease leaf in April and December. Pathogenic invasions change the citrus phyllosphere microbial community structure. It could be summarized that citrus Huanglongbing correlated with incidence of Diaphorina citri carrying Candidatus Liberibacter asiaticus and citrus phyllosphere microbiome.

In-situ co-remediation of PAHs contaminated agricultural soil using blood meal and celery: An agricultural greenhouse field study

ABSTRACT Polycyclic aromatic hydrocarbon (PAH) contaminated agricultural soil is widespread globally. To develop a cost-effective remediation technique to effectively degrade PAH contaminated agricultural soil without disturbing crop production, an in-situ co-remediation of PAH contaminated agricultural soil using blood meal and celery was assessed in an agricultural greenhouse. Results showed PAH dissipation rates increased significantly in agricultural soil when co-remediated by blood meal and celery. Planting celery and addition of 5 g•kg−1 blood meal removed 53.13% of PAHs within three months. Residual PAH concentrations in plant tissue were much lower than China Standard food limits. Results indicated the ability of celery to enhance bioavailability of PAHs, and create favorable conditions for microbial, rather than direct plant uptake, played a vital role in degradation of PAHs. Addition of blood meal significantly enhanced soil enzyme activity and PAH degradation, and increased PAH remediation rate with optimal addition of blood meal (5 g•kg−1). Celery enhanced bioavailability of PAHs. Blood meal increased soil enzyme activity and increased PAH degrading bacterial activity, which acted as the main remediation pathway to co-remediate PAHs, where celery was safe to eat. Therefore, a novel in-situ agricultural soil PAH remedial method, which did not disturb normal agricultural production during remediation is presented in this study.

Effect of Biochar on the Growth, Photosynthesis, Antioxidant System and Cadmium Content of Mentha piperita ‘Chocolate’ and Mentha spicata in Cadmium-Contaminated Soil

Cadmium (Cd) is a common heavy metal contaminant which seriously affects plant growth and environmental safety. Biochar, as an organic soil amendment, has been shown to effectively mitigate Cd damage to plants. To study the effectiveness of biochar on mitigating Cd stress, Mentha piperita ‘chocolate’ and Mentha spicata were used in a pot experiment of Cd stress with a CdCl2 solution (10 mg Kg−1), while a biochar suspension (0, 40, 80, and 160 g Kg−1) was applied to the soil. The effects of Cd on the growth, physiological and biochemical properties, and Cd content in plant tissues of both mint species were found to be significant. The application of 40 g Kg−1, 80 g Kg−1, 160 g Kg−1 biochar significantly alleviated Cd damage to both mint species, increased plant height, leaf length, leaf width, biomass, photosynthetic rate, transpiration rate, stomatal conductance, and chlorophyll content, and decreased antioxidant enzyme activities (including superoxide dismutase, catalase, peroxidase, and polyphenol oxidase) and non-enzymatic antioxidant content (including flavonoids and total phenols). Biochar effectively reduced the Cd uptake by plants and decreased the migration and transformation capacity of Cd in the soil–plant system. In addition, the available nitrogen (available N), available phosphorus (available P), available potassium (available K), and pH in the soil increased after biochar application compared to non-biochar amended soil. The addition of 160 g Kg−1 biochar was shown to have the best performance of the application rates in this experiment and may be considered as an effective way to reduce the damage caused by Cd contamination to M. piperita ‘chocolate’ and M. spicata.

Nitrogen fertilization and CO2 concentration synergistically affect the growth and protein content of Agropyron mongolicum.

The nitrogen (N) and protein concentrations in plant tissues exposed to elevated CO2 (eCO2) generally decline , such declines in forage grass composition are expected to have negative implications for the nutritional and economic value of grass. Plants require N for the production of a photosynthetically active canopy and storage proteins in the tissues, whose functionality will strongly influence productivity and quality. The objective of this study was to investigate whether eCO2 plus N-fertilization increases growth and N nutrition of Agropyron mongolicum, and the dependence of this improvement on the coordination between root and leaf development. We analyzed A. mongolicum from field-grown within the open-top chambers (OTCs) facility under two atmospheric CO2 (ambient, 400 ± 20 µmolmol-1, aCO2, and elevated, 800 ± 20 µmolmol-1, eCO2) and three N-fertigation treatments (control, low N-fertigation , and high N-fertigation) for two months. Elevated CO2 plus N-fertigation strongly increased shoot and root biomass, and the nitrogen and protein concentrations of A. mongolicum compared to those plants at aCO2 levels. Increased N content in leaves and reduced specific leaf area (SLA) at a high N supply could alleviate photosynthetic acclimation to eCO2 and drive the production of greater shoot biomass with the potential for higher photosynthesis, productivity, and nutritional quality. The increased root length (RL), the ratio of total aboveground N taken up per RL (TN/RL), stomatal conductance (Gs), and transpiration rate (Tr) contribute to the transpiration-driven mass flow of N, consequently increasing N uptake by roots. In addition, a smaller percentage of N remained as unassimilated nitrate ( ) under eCO2, indicating that assimilation of into proteins was not inhibited by eCO2. These findings imply that grass productivity and quality will enhance under anticipated elevated CO2 concentration when effective management measures of N-fertilization are employed.

If All Else Fails: Impact of Silicon Accumulation in Maize Leaves on Volatile Emissions and Oviposition Site Selection of Spodoptera exigua Hübner.

Silicon (Si) fertilization alleviates biotic stresses in plants. Si enhances plant resistance against phytophagous insects through physical and biochemical mechanisms. In particular, Si modifies jasmonic acid levels and the emissions of herbivore-induced plant volatiles (HIPVs). Here, we investigated whether Si accumulation in the tissues of maize leaves modifies the emissions of constitutive and herbivore-induced plant volatiles, with cascade deterrent effects on oviposition site selection by Spodoptera exigua Hübner (Lepidoptera: Noctuidae). Maize plants were cultivated in a hydroponic system under three Si concentrations, resulting in three groups of plants expressing different Si concentrations in their tissues (0.31 ± 0.04, 4.69 ± 0.49, and 9.56 ± 0.30g Si. Kg- 1 DW). We collected volatiles from undamaged and caterpillar-infested plants, and found that Si concentration in plant tissues had no significant impact. Jasmonic acid content was high in insect-infested plants, but was similar across all Si treatments. Oviposition site selection bioassays using fertilized S. exigua females showed that Si concentration in plant tissues did not affect the number of eggs laid on Si-treated plants. In conclusion, our study shows that the Si content in maize tissues does not impact the semiochemical interactions with S. exigua.

Modeling the fate of ionizable pharmaceutical and personal care products (iPPCPs) in soil-plant systems: pH and speciation

A model was developed to simulate the pH-dependent speciation and fate of ionizable pharmaceutical and personal care products (iPPCPs) in soils and their plant uptake during thedt application of reclaimed wastewater to agricultural soils. The simulation showed that pH plays an important role in regulating the plant uptake of iPPCPs, i.e., ibuprofen (IBU; with a carboxylic group), triclosan (TCS; phenolic group), and fluoxetine (FXT; amine group) as model compounds. It took 89–487 days for various iPPCPs to reach the steady-state concentrations in soil and plant tissues. The simulated steady-state concentrations of iPPCPs in plant tissues at pH 9 is 2.2–2.3, 2.5–2.6, and 1.07–1.08 times that at pH 5 for IBU, TCS, and FXT, respectively. Assuming sorption only for neutral compounds led to miscalculation of iPPCPs concentrations in plant tissues by up to one and half orders magnitude. Efflux of compounds in soil, lettuce leaf, and soybean pods was primarily contributed by their degradation in soil and dilution due to plant tissue growth. Overall, the results demonstrated the importance of considering pH and speciation of iPPCPs when simulating their fate in the soil-plant system and plant uptake.

Assessment of selenium and zinc enriched sludge and duckweed as slow-release micronutrient biofertilizers for Phaseolus vulgaris growth

Selenium (Se) and zinc (Zn) are essential micronutrients that are often lacking in the diet of humans and animals. Application of mineral Se and Zn fertilizers into soils may lead to a waste of Se and Zn due to the fast leaching and low utilization by plants. Slow-release Se and Zn biofertilizer may therefore be beneficial. This study aims to assess the potential of SeZn-enriched duckweed and sludge produced from wastewater as slow-release Se and Zn biofertilizers. Pot experiments with green beans (Phaseolus vulgaris) and sampling of Rhizon soil pore water were conducted to evaluate the bioavailability of Se and Zn in sandy and loamy soils mixed with SeZn-enriched duckweed and sludge. Both the Se and Zn concentrations in the soil pore water increased upon amending the two biomaterials. The concentration of Se released from SeZn-enriched duckweed rapidly decreased in the first 21 days and slowly declined afterwards, while it remained stable during the entire experiment upon application of SeZn-enriched sludge. The Zn content in the soil pore water gradually increased over time. The application of SeZn-enriched duckweed and sludge significantly increased the Se concentrations in plant tissues, in particular in the form of organic Se-methionine in seeds, without a negative impact on plant growth when an appropriate dose was applied (1 mg Se/kg soil). While, it did not increase Zn concentrations in plant seeds. The results indicate that the SeZn-enriched duckweed and sludge could be only used as organic Se biofertilizers for Se-deficient soils. Particularly, the SeZn-enriched sludge dominated with elemental nano-Se was an effective Se source and slow-release Se biofertilizer. These results could offer a theoretical reference to choose an alternative to chemical Se fertilizers for biofortification, avoiding the problem of Se losses by leaching from mineral Se fertilizers while recovering resources from wastewater. This could contribute to the driver for a future circular economy.

Mining Candidate Genes Related to Heavy Metals in Mature Melon (Cucumis melo L.) Peel and Pulp Using WGCNA.

The content of metal ions in fruits is inseparable from plant intake of trace elements and health effects in the human body. To understand metal ion content in the fruit and pericarp of melon (Cucumis melo L.) and the candidate genes responsible for controlling this process, we analyzed the metal ion content in distinct parts of melon fruit and pericarp and performed RNA-seq. The results showed that the content of metal ions in melon fruit tissue was significantly higher than that in the pericarp. Based on transcriptome expression profiling, we found that the fruit and pericarp contained elevated levels of DEGs. GO functional annotations included cell surface receptor signaling, signal transduction, organic substance metabolism, carbohydrate derivative binding, and hormone-mediated signaling pathways. KEGG pathways included pectate lyase, pentose and glucuronate interconversions, H+-transporting ATPase, oxidative phosphorylation, plant hormone signal transduction, and MAPK signaling pathways. We also analyzed the expression patterns of genes and transcription factors involved in hormone biosynthesis and signal transduction. Using weighted gene co-expression network analysis (WGCNA), a co-expression network was constructed to identify a specific module that was significantly correlated with the content of metal ions in melon, after which the gene expression in the module was measured. Connectivity and qRT–PCR identified five candidate melon genes, LOC103501427, LOC103501539, LOC103503694, LOC103504124, and LOC107990281, associated with metal ion content. This study provides a theoretical basis for further understanding the molecular mechanism of heavy metal ion content in melon fruit and peel and provides new genetic resources for the study of heavy metal ion content in plant tissues.

Pengaruh Penyerapan Eceng Gondok (Eichornia crassipes) Dan Apu Apu (Pistia stratiotes) Terhadap Konsentrasi Cu Dan Zn Pada Air Limbah Pertambangan PT J Resources Bolaang Mongondow

This research aims to analyze the concentration of Cu, Zn, and pH in mining wastewater at the Pit Osela of PT J Resources Bolaang Mongondow (JRBM) and the effect of absorption of water hyacinth (eichhornia c) and water lettuce (pistia stratiotes) on heavy metals Cu, Zn and pH in plant tissues. Research Methods: The study was located in PT JRBM's greenhouse in Bolaang Mongondow Regency with Mining Wastewater (ALP) in Pit Osela (mining). The results: Cu concentration in ALP Pit Osela in the initial condition was 15.59 mg/l. The decrease in Cu concentration by water hyacinth started from 7.02 mg/l to 15.48 mg/l with an effectiveness of 45% to 99.3%. The concentration of Cu after being given water lettuce on the third day (38 days) was 0.12 mg/l. The concentration of Cu on the third day group was 8.51 mg/l. The concentration of Zn in ALP in Pit Osela (mining area) in the initial condition was 7.03 mg/l, after being given water hyacinth and water lettuce on the third day (38 days) it became 0.00 mg/l. The concentration of Zn in the control group on the first day was 7.01 mg/l, on the third day it was 7.01 mg/l. The pH concentration of ALP in the Osela Pit in the initial condition was 3.03. Increasing the concentration of pH with aquatic plant treatment after some time finally the wastewater can meet the environmental quality standard (BML) 6-9. The control group that was not given water plants, the initial concentration was pH 3.03, the pH on the first day was 3.30, the second and third days the concentration was the same, namely 3.30. There is an effect of absorption of water hyacinth and water lettuce on Cu and Zn content in plant tissues (leaves and roots).