Salt Tolerance Research Articles

The Effects of Salinity on Aquatic Plant Growth in Ethiopia

Purpose: The aim of the study was to investigate the effects of salinity on aquatic plant growth in Ethiopia. Methodology: This study adopted a desk methodology. A desk study research design is commonly known as secondary data collection. This is basically collecting data from existing resources preferably because of its low cost advantage as compared to a field research. Our current study looked into already published studies and reports as the data was easily accessed through online journals and libraries. Findings: Salinity negatively impacts aquatic plant growth in Ethiopia, reducing seed germination, photosynthesis, and nutrient uptake, leading to stunted growth. Studies in the Awash River Basin and Rift Valley lakes show that high salt levels cause osmotic stress, ion toxicity, and oxidative damage, weakening freshwater plants like papyrus and water hyacinth. Adaptive strategies, such as salt-tolerant species, better water management, and riparian afforestation, are essential for ecosystem restoration. Unique Contribution to Theory, Practice and Policy: Osmotic stress theory, ion toxicity and selectivity theory & salt tolerance mechanism theory may be used to anchor future studies on the effects of salinity on aquatic plant growth in Ethiopia. Practical experiments using hydroponic systems and controlled salinity environments should be conducted to optimize plant growth in brackish and saltwater conditions. Governments and environmental organizations should establish clear guidelines for salinity thresholds in aquatic ecosystems to safeguard biodiversity and freshwater resources.

A plant endophytic bacterium Burkholderia seminalis strain 869T2 increases plant growth under salt stress by affecting several phytohormone response pathways.

Due to global warming and gradual climate change, plants are subjected to a wide range of environmental stresses, adversely affecting plant growth and production worldwide. Plants have developed various mechanisms to overpower these abiotic stresses, including salt stress, drought, and high light intensity. Apart from their own defense strategies, plants can get help from the beneficial endophytic bacteria inside host plants and assist them in enduring severe growth conditions. A previously isolated plant endophytic bacteria, Burkholderia seminalis 869T2, from vetiver grass can produce auxin, synthesize siderophore, and solubilize phosphate. The B. seminalis 869T2 can colonize inside host plants and increase the growth of bananas, Arabidopsis, and several leafy vegetables. We further demonstrated that different growth parameters of Arabidopsis and pak choi plants were significantly increased after inoculating the B. seminalis 869T2 under normal, salt, and drought stress conditions compared to the mock-inoculated plants. Both transcriptome analysis and quantitative real-time PCR results showed that expression levels of genes related to phytohormone signal transduction pathways, including auxin, gibberellin, cytokinin, and abscisic acid were altered in Arabidopsis plants after inoculated with the strain 869T2 under salt stress, in comparison to the mock-inoculated control with salt treatments. Furthermore, the accumulation levels of hydrogen peroxide (H2O2), electrolyte leakage (EL), and malondialdehyde (MDA) were lower in the 869T2-inoculated Arabidopsis and pak choi plants than in control plants under salt and drought stresses. The plant endophytic bacterium strain B. seminalis 869T2 may affect various phytohormone responses and reduce oxidative stress damage to increase salt and drought stress tolerances of host plants.

Stutzerimonas stutzeri culture enhances microbial community structure and tomato seedling growth in saline soil.

Plant growth-promoting rhizobacteria (PGPR) improve microbial community structure, promote crop growth, and reduce greenhouse gas emissions in agricultural soils; however, the effects of PGPR fermentation on the growth and salt tolerance of tomato plants remain unclear. In this study, we aimed to investigate the effects of the PGPR Stutzerimonas stutzeri NRCB010 on the microbial communities, tomato growth, and nitrous oxide (N2O) emissions in saline soil by performing a greenhouse pot experiment. The experiment was conducted under two soil salt concentrations (0 and 3 g kg-1 NaCl) and three treatments (LSFJ broth, NRCB010 cells, and NRCB010 culture). Both salt stress and NRCB010 treatments significantly affected the physicochemical properties and microbial community structure of tomato rhizosphere soil. Treatment with 3 g kg-1 NaCl significantly reduced the shoot and root dry weights of the plants compared with those of the control plants. Application of NRCB010 cells as well as that of culture promoted the growth of tomato seedlings and alleviated salt stress. The copy number changes in the nosZⅠ gene on day 3 and amoA gene on day 25 demonstrated that NRCB010 cells significantly reduced soil N2O emissions when treated with 0 g kg-1 NaCl. Furthermore, soil physicochemical properties, plant biomass, and soil microbial diversity were correlated with each other. The results emphasize the enormous potential of S. stutzeri NRCB010 culture to resist abiotic stress, promote crop growth, and improve the rhizosphere soil microenvironment; however, its ability to decrease N2O emissions is constrained by soil salinity.

Evaluation of Antibiotic-Sensitive Bacillus Strain as a Potential Probiotic for Enhanced Growth in Penaeus vannamei.

The safety of probiotics in aquaculture, particularly concerning the transfer of antibiotic resistance genes (ARGs), has become a significant concern. This study aims to isolate antibiotic-sensitive Bacillus strains from the gut of Penaeus vannamei and evaluate the potential for practical application in shrimp farming. The strain was tested for antibiotic sensitivity to 10 commonly used antibiotics, and the minimum inhibitory concentration (MIC) values were determined. Morphological analysis and 16S rRNA sequencing confirmed its identity. The probiotic properties, antibacterial activity, and feeding effects on P. vannamei were also assessed. The results showed that Bacillus sp. J3 and Lysinibacillus sp. R4 were generally sensitive to antibiotics but resistant to sulfapyridine and ciprofloxacin. Both strains exhibited acid and bile salt resistance in vitro and performed well in extracellular hydrolase tests. J3 demonstrated co-coagulation effects against Aeromonas veronii, Vibrio parahaemolyticus, and Vibrio alginolyticus, with coagulation rates over 35%, while R4 showed the highest co-coagulation rate (47%) against V. alginolyticus. Both strains exhibited strong antibacterial activity, with inhibition zones ranging from 20 to 22.5mm. Preliminary shrimp farming tests showed that R4 improved shrimp growth and survival rates compared to the control, and its combination with Bacillus coagulans resulted in even greater efficacy. These findings suggest that Lysinibacillus sp. R4 holds promise as a probiotic for enhancing P. vannamei growth, and future research could explore the use of multiple probiotic combinations in aquaculture.

Mitigation of salinity stress in salt-sensitive rice seedlings via phytohormone synthesis, antioxidant defence enhancement, and ion balance regulation induced by 5-aminolevulinic acid-producing purple non-sulfur bacteria.

Salt stress, intensified by climate change, is a significant threat to rice production, a vital staple for over half the world's population. This makes addressing salt stress in rice cultivation a pressing issue. This study investigates the role of PNSB as a biostimulant in enhancing salinity tolerance of salt-sensitive rice seedlings, addressing existing gaps in knowledge on physiological and biochemical impacts under saline stress. We inoculated salt-sensitive rice seedlings with PNSB under 80 mmol NaCl stress in a controlled environment. After a 5-day treatment, we conducted biochemical and physiological analyses. Salinity stress induced oxidative stress in salt-sensitive rice seedlings. However, application of 5-ALA-producing PNSB mitigated stress, elevated 5-ALA in shoots by 23%, roots by 190.5%, and chlorophyll content by 105.0%. PNSB treatment also reduced superoxide radicals (O2 •-) and H2O2 by 26.7% and 38.7%, respectively, related to increased activity of the antioxidant enzymes, SOD (142.9%) and APX (41.8%). This led to lower electrolyte leakage (25.2%) and MDA (17.4%), indicating reduced ROS. Additionally, proline and soluble sugar content decreased by 29.2% and 72.5%, respectively. PNSB treatment also reduced sodium to potassium ion content in both shoots (31.2%) and roots (27.4%) of salt-stressed rice seedlings. These findings suggest that PNSB may facilitate nutrient solubilization and ion balance, thereby mitigating the adverse effects of salinity, with potential implications for sustainable agricultural practices to improve crop yield in saline environments. Future research should focus on elucidating the specific biochemical pathways involved in PNSB-mediated stress tolerance and exploring their application across diverse crop species and varying stress conditions.

The role of model crowders in the salt resistance of complex coacervates.

Complex coacervation is the phase separation of oppositely charged polyelectrolytes, resulting in a polymer-dense coacervate phase and a polymer-depleted supernatant phase. Coacervation is crucial for many biological processes and novel synthetic materials, where the environment is often filled with other neutral molecules (crowders). Yet, the complex role of crowders in complex coacervation has not been studied systematically under controlled conditions. We performed coarse-grained molecular dynamics simulations of coacervation in the presence of polymeric crowders of varying concentrations and chain lengths. While short crowders do not have any significant effect on coacervation, larger crowders stabilize the coacervate against added salt, increasing its critical salt concentration. The change in critical salt concentration saturates for long crowders at a value determined by the crowder concentration. Rescaling all phase diagrams by their critical salt concentration leads to a collapse of the data, which demonstrates a universal phase behavior. Our simulation indicates that the inability of crowder chains to mix with the polyelectrolytes is the driving force behind crowding effects. These testable predictions provide a first step toward a comprehensive understanding of crowding effects in complex coacervation.

Using Klebsiella sp. and Pseudomonas sp. to Study the Mechanism of Improving Maize Seedling Growth Under Saline Stress

The increasing salinization of cultivated soil worldwide has led to a significant reduction in maize production. Using saline–alkaline-tolerant growth-promoting bacteria (PGPR) in the rhizosphere can significantly improve the saline tolerance of maize and ensure the stability of maize yields, which has become a global research hotspot. This study screened salt-tolerant microorganisms Klebsiella sp. (GF2) and Pseudomonas sp. (GF7) from saline soil to clarify the mechanism in improving the saline tolerance of maize. In this study, different application treatments (GF2, GF7, and GF2 + GF7) and no application (CK) were set up to explore the potential ecological relationships between the saline tolerance of maize seedlings, soil characteristics, and microorganisms. The results showed that co-occurrence network and Zi-Pi analysis identified Klebsiella and Pseudomonas as core microbial communities in the rhizosphere soil of maize seedlings grown in saline soil. The deterministic process of microbial assembly mainly controlled the bacterial community, whereas bacteria and fungi were governed by random processes. The application of saline–alkaline-resistant PGPR under saline stress significantly promoted maize seedling growth, increased the activity of soil growth-promoting enzymes, and enhanced total nitrogen, soil organic carbon, and microbial carbon and nitrogen contents. Additionally, it reduced soil salt and alkali ion concentrations [electrical conductivity (EC) and exchangeable Na+]. Among them, GF2 + GF7 treatment had the best effect, indicating that saline–alkaline-tolerant PGPR could directly or indirectly improve the saline tolerance of maize seedlings by improving the rhizosphere soil ecological environment. EC was the determining factor to promote maize seedling growth under saline–alkaline stress (5.56%; p < 0.01). The results provided an important theoretical reference that deciphers the role of soil factors and microecology in enhancing the saline tolerance of maize.

Comparative transcriptome analysis and functional verification revealed that GhSAP6 negatively regulates salt tolerance in upland cotton.

Owing to the scarcity of cultivable land in China, the agricultural sector is primarily focused on grain and oil crops. Simultaneously, the cultivation of cotton has gradually shifted towards regions characterized by elevated soil salinity levels. Additionally, the mechanism behind cotton's ability to tolerate salt remains elusive. In this study, we identified the Z9807 genotype as highly tolerant to salt stress, exhibiting superior leaf wilting resistance, antioxidant activity, catalase activity, K+/Na+ ratio, and growth compared to the salt-sensitive ZJ0102. Comparative transcriptome analysis revealed marked differences in salt stress responses between Z9807 and ZJ0102. This study identified a considerable number of differentially expressed genes associated with salt tolerance across multiple time points. By integration of QTL and GWAS mapping data, we successfully identified 621 candidate genes associated with salt tolerance. Weighted gene correlation network analysis exhibited three co-expression modules related to salt-tolerant Z9807 samples, ultimately identifying 15 core salt-tolerant candidate genes. We also conducted in-depth research on the salt tolerance of the stress-associated protein (SAP) GhSAP6 (GhSAP6_At and GhSAP6_Dt homologs). Results revealed that these candidate genes may inhibit salt tolerance through Virus-Induced Gene Silencing (VIGS) and transgenic overexpression assays conducted in Arabidopsis thaliana. Furthermore, we used yeast two-hybrid and luciferase assay experiments to confirm the ubiquitin degradation pathway between selected interacting proteins and verified the interaction with RAD23C. This study will provide new insights into the mechanisms related to salt tolerance in upland cotton.

A small peptide miPEP172b encoded by primary transcript of miR172b regulates salt tolerance in rice.

Recent studies have demonstrated that the primary transcript of miRNAs (pri-miRNAs) are able to encode small peptides influencing plant growth and development, as well as responses to various environmental cues. However, their role in plant responses to salt stress is not fully comprehended. Here, we characterized a short peptide encoded by miR172b (miPEP172b) in rice (Oryza sativa L.). By applying synthetic miPEP172b, we observed a significant increase in miR172b abundance and a decrease in the expression of its target gene IDS1. Consequently, plants treated with miPEP172b exhibited enhanced tolerance to salinity stress. Furthermore, we found that miPEP172b was efficiently absorbed by roots and transported to the aerial parts of the plant, thus conferring salt tolerance in the aboveground organs. Overexpression of miPEP172b resulted in reduced levels of reactive oxygen species (ROS), leading to improved performance of rice seedlings under salinity conditions. This was consistent with the observations in miR172-overexpressing plants. Conversely, miPEP172b mutants showed increased sensitivity to salt stress. Further analysis revealed that miPEP172b-miR172-IDS1 improved rice salt tolerance by integrating the ROS scavenging pathway and plant hormone signaling. Our findings highlight the significant role of miPEP172b in regulating miR172 activity and salt tolerance, providing a useful agent for improving crop salt tolerance.

Systematic identification and analysis of the HSP70 genes reveals MdHSP70-38 enhanced salt tolerance in transgenic tobacco and apple.

Heat shock protein 70 (HSP70) is a class of important molecular chaperones that are involved in protein folding, stabilization, and maturation, and play a vital role in plant growth and response to environmental stress. Apple trees frequently suffer from different-degree salt stress, which seriously affects their growth, quality, and yield. However, whether HSP70 genes are involved in salt tolerance is unexplored in apple. In this study, 67 MdHSP70 genes were identified and unevenly distributed on 17 apple chromosomes. Gene structure and protein motif analysis revealed that MdHSP70 genes in the same subgroup have similar intron phase and motif organization, further supporting the phylogenetic results. RNA-seq analysis showed the expression level of nine of 67 MdHSP70 genes was induced by salt stress. Subsequent qRT-PCR analysis revealed that MdHSP70-38 was dramatically up-regulated in response to salt stress. The overexpression of MdHSP70-38 in transgenic tobacco and apple improved salt stress tolerance, which was associated with less electrolyte leakage and malondialdehyde (MDA), as well as diminished accumulation of hydrogen peroxide (H2O2) and superoxide radicals (O2-). Our findings demonstrated that MdHSP70-38 played a positive regulatory role in salt tolerance in tobacco and apple, and provided a promising candidate gene in genetic applications for improving salt tolerance.

Pepper (Capsicum annuum L.) AP2/ERF transcription factor, CaERF2 enhances salt stress tolerance through ROS scavenging.

The AP2/ERF transcription factor CaERF2 in pepper enhanced salt tolerance by scavenging reactive oxygen species. The effects of salt stress on plant development and progression are substantial. Ethylene response factor transcription factors (TFs) play a crucial role in responses to salt stress. Their functions in the salt response, particularly in pepper, are still mostly unknown. This study revealed the function of CaERF2 in salt tolerance of pepper plants. CaERF2 expression was dramatically increased in pepper plants following salt stress treatment. Under salinity treatment, CaERF2-silenced pepper showed decreased activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), as well as reduced transcription levels of reactive oxygen species (ROS) scavenging-related genes, resulting in increased O2- and H2O2 accumulation and enhanced salt sensitivity. In contrast, overexpression of CaERF2 (OE) in Nicotiana benthamiana resulted in improved salt tolerance. Under salt stress, the OE lines outperformed the wild type in terms of seed germination rates, root lengths, the activity of SOD, POD, and CAT, and ROS-scavenging-related gene transcription. This study demonstrates that CaERF2 effectively enhances the salt tolerance in pepper by adjusting ROS homeostasis. This finding offers fresh perspectives on the significance of plant ERF2 and key candidate genes in the molecular breeding of salt-tolerant crops.

Identification of a Novel QTL on LG16 Associated with Acute Salt Tolerance in Red Tilapia (Oreochromis spp.) Using GWAS.

Culturing saline tilapia has become a new trend in the aquaculture due to the scarcity of freshwater resources. In this study, the genetic basis controlling for salt tolerance were investigated by using a ddRAD-seq-based GWAS in 288 individuals with extreme salt tolerant traits from half-sib families of red tilapia. 12 genome-wide significant SNPs and 6 chromosome-wide significant SNPs associated with acute salt tolerance were identified. Two QTLs on LG18:25,593,701-7009020 and on LG16:19,735,164-21,231,391 were defined. It is noteworthy that the QTL on LG16 is a novel QTL associated with acute salt stress. Near the significant SNP sites, we identified candidate genes sik1, ltb4r2b, pnp5b and kirrel1b with differential transcript expression under salt stress. Furthermore, significant physiological differences in serum osmolality and ion concentrations were confirmed between the tolerant group and sensitive group under 4.5h of 22 ppt stress. The sensitive group had much higher serum osmolality (osmolality: 642.20 ± 6.30mOsm/kg) and higher concentrations of sodium and chloride ions (sodium: 317.67 ± 5.03mmol/L and chloride: 316.43 ± 8.28mmol/L) than the tolerant group (547.60 ± 15.44mOsm/kg, p osmolality = 0.0002; sodium: 280.53 ± 9.13 mmol/L, p sodium < 0.0242; chloride: 266.00 ± 12.00 mmol/L, p chloride < 0.0184). However, the lowest bicarbonate concentration was detected in the sensitive group at 22 ppt (2.53 ± 0.30mmol/L), which was significantly different from both the sensitive group at 0 ppt (p = 0.0008) and the tolerant group at 22 ppt (p = 0.0164). Our research laid the foundation for exploring the genetic mechanisms of acute salt tolerance and osmoregulation in red tilapia and for developing strains of red tilapia adapted to saltwater.

Comprehensive evaluation of physio-morphological traits of alfalfa (Medicago sativa L.) varieties under salt stress.

Salt is a major abiotic factor significantly affecting plant growth and development. Alfalfa (Medicago sativa L.), a crucial perennial crop for livestock feed, shows significant differences in salt tolerance among different varieties. This study aimed to comprehensively evaluate the salt tolerance of 30 varieties of alfalfa under salt stress (0, 150, and 300 mmol L-1 NaCl). It showed that shoot height (SH), root length (RL), shoot fresh weight (SFW), and root fresh weight (RFW) were decreased by 37.68%, 35.83%, 43.79% and 48.86%, respectively, under high salt stress. Photosynthesis-related parameters, including chlorophyll a (Chl a), chlorophyll b (Chl b), total chlorophyll (TChl), and carotenoids (Car) contents of all varieties were decreased by 50.13%, 43.73%, 48.17% and 60.86%, respectively, and minimum inhibition of photosynthetic pigment contents was observed in the variety Salsa. The changes of antioxidant enzymes in different alfalfa varieties were also found under salt stress. For example, the APX of Sardi 7 decreased by 641.84%, while the APX of Phabulous decreased by 88.33% compared to the non-treated controls. Principal component analysis (PCA) identified five major variables: Car, TChl, APX, Chl a, and POD. Finally, each variety's comprehensive tolerance membership function values were calculated by the membership function method, and the 30 varieties were classified into four categories by cluster analysis. Our findings indicate that Sardi 7, Salsa, Gannong No.8, Daye, and Instinct are alfalfa salt-tolerant varieties. Our study provided baseline information on the response of alfalfa varieties to different salinity levels, which will help select or breed salt-tolerant varieties.

3D hydrogel-based salt resistant self-floating solar-driven interfacial evaporator with efficient water-lifting capacity for desalination

Solar desalination has been extensively researched as a promising way to address freshwater shortages. However, developing a salt resistant solar evaporator that can be easily extended and manufactured is still a challenge in practical applications. In this work, a 3D hydrogel-based salt resistant self-floating solar-driven interfacial evaporator with efficient water-lifting capacity was proposed using the prepared hydrogel with carbon black (CB) nanoparticles and extruded polystyrene (XPS) board as raw materials. The experimental results implied that the developed evaporator had the highest evaporation rate and evaporation efficiency at 0.05 g CB loading, which were 1.70 kg m-2h−1 and 92.8 % at a light intensity of 1 kW/m−2(−|-). Moreover, the evaporator also displayed prominent salt resistance in the evaporation of brine with high salinity and outstanding stability after 10 cycles. Significantly, the outdoor experiment demonstrated that 1 m2 evaporator can generate 5923.5 g freshwater per day, which was enough to meet the daily requirement of two adults for drinking water. In addition, the physical fields of the hydrogel with CB nanoparticles of the evaporator at evaporation equilibrium were simulated to analyze its long-term and high-performance operation capability. All in all, the 3D hydrogel-based salt resistant self-floating solar-driven interfacial evaporator with efficient water-lifting capacity presented an enormous application prospect in the field of solar desalination.

Enhanced Salt Tolerance of Pea (Pisum sativum L.) Seedlings Illuminated by LED Red Light

Light quality is an important variable affecting plant growth, so we aimed to explore the impact of light quality on plants under salt stress. The salt tolerance of pea (Pisum sativum L.) seedlings illuminated by LED red light and 4:1 of red/blue light in a hydroponic system was evaluated at three salinity levels (0, 50, and 100 mmol/L of NaCl) for their morphological and physiological parameters and their root growth characteristics in response to salt stress. Results demonstrated that, as salt stress intensified, the plant height, aboveground fresh/dry mass, root growth indices, and chlorophyll content of pea seedlings exhibited a decreasing trend, while the malondialdehyde (MDA) content and the activity of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in leaves increased. Also, more sodium (Na⁺) but less potassium (K⁺) ions were detected due to the change in electrolyte balance. Compared with pea seedlings under no salt stress, the growth rate, plant height, and K⁺ ion content significantly increased with the red light treatments, but both lights did not affect the aboveground fresh/dry mass, chlorophyll content, or root growth index. Under medium salt stress (50 mmol/L), red light helped generate more chlorophylls by 17.06%, accelerate leaf electrolyte exudation by 23.84%, accumulate more K⁺ ions by 46.32%, and increase the K⁺/Na⁺ ratio by 45.45%. When pea seedlings were stressed by 100 mmol/L salinity stress, red light was able to maintain the leaf chlorophyll level by 114.66%, POD enzyme activity by 157.78%, MDA amount by 14.16%, leaf and stem electrolyte leakage rate by 38.76% and 21.80%, respectively, K⁺ ion content by 45.47%, and K⁺/Na⁺ ratio by 69.70%. In conclusion, the use of red light has proven to enhance the salt tolerance of pea seedlings in a hydroponic system, which can and should be a promising approach to prime pea seedlings for more salt tolerance.

Investigation into the mechanisms of photosynthetic regulation and adaptation under salt stress in lavender.

Salinity stress is a major threat to agricultural productivity and sustainability, often causing irreversible damage to photosynthesis. Lavender, a valuable aromatic plant, experiences growth impacts under salt stress. However, the regulatory mechanisms of photosynthesis related to its adaptation to salt stress remain unclear. In this study, lavender was exposed to 0, 100, 200, and 300mM NaCl for 28 days. It was observed that lavender effectively maintained chlorophyll stability when salt concentrations were below 200mM and stress duration was under 21 days. The most effective model for lavender under salt stress was identified as a right-angled hyperbolic modified model. Under moderate salt stress (100mM, 200mM), genes such as LaPSB28, LaPSBS, and LaPSBR contributed to PSII core stability, enhanced photosynthetic pigment levels, and sustained high electron transfer rates to improve salt-tolerance. Additionally, LaLHCB4-1 and LaPSAK-1 regulated stomatal size, thereby facilitating gas exchange and supporting the photosynthetic process. Conversely, under high salt stress (300mM), LaPSBW-1, -2, and LaPSAB were found to reduce photosynthetic pigment levels and inhibit photosynthetic activity. However, genes such as LaCHLG-2, LaGLG-3, LaBAM1-1 and -3, and LaCHLP-3 aided in starch synthesis by increasing pigment content, thus promoting energy balance and enhancing salt tolerance. This regulation involved photosynthesis-antenna proteins and pathways related to starch, sucrose, and chlorophyll metabolism. These findings may support the cultivation of salt-tolerant lavender varieties and maximize saline soil usage.

Ammonium sulfite slurry activates lignite for water-soluble humic acid: Catalytic oxidation, characteristics, and salt tolerance in rice

Ammonium sulfite slurry activates lignite for water-soluble humic acid: Catalytic oxidation, characteristics, and salt tolerance in rice

A Chromosome-Level Genome Sequence Reveals Regulation of Salt Stress Response in Mesembryanthemum crystallinum.

Salt stress disturbs plant growth and photosynthesis due to its toxicity. The ice plant Mesembryanthemum crystallinum is a highly salt-tolerant facultative crassulacean acid metabolism (CAM) plant. However, the genetic basis of the salt tolerance mechanisms in ice plants remains unclear. In this study, we constructed a chromosome-level whole-genome sequence of the ice plant and performed transcriptome analysis of the effects of salt treatment on the leaves. After 24-hour 500 mM NaCl treatment to the roots, 1100 and 1394 genes, including CAM pathway, glycolysis, and inositol metabolism, were up- and down-regulated in the leaves, respectively. Salt treatment also influenced the abscisic acid (ABA) signaling components, including genes from the PYRABACTIN RESISTANCE1 (PYR1) family and the PROTEIN PHOSPHATASE 2CA (PP2CA) family. We detected the induction of the genes encoding various ion transporters after salt treatment. The expression of most v-ATPase subunits is induced, leading to vacuolar acidification, which facilitates sodium ion sequestration in the vacuoles. Additionally, some genes encoding metal ion transporters, including the genes from the ZIP family and NRAMP family, were induced by salt treatment, accompanied by the accumulation of iron, zinc, and copper ions in the leaves. Cis-motif enrichment analysis revealed that ABRE-like motifs and MYB-binding-like motifs were enriched in the upstream sequences of genes that were either up-regulated or down-regulated by salt. In conclusion, this study highlights how salt treatment induces drastic and rapid transcriptomic changes and unveils the ice plant's genomic foundation. Our resources provide further insights into the regulation of salt tolerance in the ice plants.

Hofmeister effect-inspired attapulgite-based monoliths for stable solar-driven interfacial vapor generation with salt and acid resistance

Hofmeister effect-inspired attapulgite-based monoliths for stable solar-driven interfacial vapor generation with salt and acid resistance

A Janus biomass-derived photothermal material with low enthalpy of evaporation and high salt tolerance for efficient solar evaporation

A Janus biomass-derived photothermal material with low enthalpy of evaporation and high salt tolerance for efficient solar evaporation