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Salt stress is a critical abiotic factor that adversely affects plant growth and productivity by impairing photosynthesis. This study explores the impact of exogenous ascorbic acid (AsA) on the photosynthetic performance of tomato seedlings (Solanum lycopersicum L. cv. Ligeer 87-5) under salt stress. Hydroponic experiments were conducted in a solar greenhouse, where tomato seedlings were subjected to the following five treatments: Control, NaCl, NaCl + AsA, NaCl + lycorine (LYC), and NaCl + LYC + AsA. Our findings demonstrate that salt stress significantly reduced chlorophyll and carotenoid contents, levels of chlorophyll synthesis precursors (5-aminolevulinic acid (ALA), porphobilinogen (PBG), uroporphyrinogen III (Urogen III), protoporphyrin IX (Proto IX), magnesium protoporphyrin IX (Mg-Proto IX), protochlorophyllide (Pchl)), and essential elements (Mg, Fe, Mn, Zn, Mo, and P) in both roots and leaves. These reductions led to a substantial decline in net photosynthetic rate (Pn) and compromised photosystem II (PSII). In contrast, exogenous AsA application significantly enhanced the content of photosynthetic pigment precursors and essential elements, improved stomatal aperture and gas exchange efficiency, and boosted the photosynthetic performance of tomato seedlings under salt stress. Furthermore, AsA treatment mitigated the negative effects of salt stress by protecting PSII, increased light energy utilization efficiency, and alleviated both stomatal and non-stomatal limitations. The application of the AsA synthesis inhibitor LYC exacerbated the detrimental effects of salt stress, further reducing chlorophyll content and photosynthetic efficiency. In conclusion, exogenous AsA plays a vital role in enhancing the photosynthetic performance and stress tolerance of tomato seedlings under salt stress by stabilizing chlorophyll biosynthesis, facilitating essential element absorption, and optimizing stomatal function. This study provides a new approach and feasible measures for improving tomato resistance and yield, which is significant for enhancing crop productivity, managing saline soils, and promoting sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

The low solubility and enhanced fixation of zinc (Zn) in semi-arid and dry climates limits Zn uptake in plants. Zn deficiency in soil impairs crop production and human health, necessitating agricultural biofortification. A pot experiment was conducted to evaluate the effect of Zn and various types of manure on the Zn biofortification of lentils. The treatments, consisting of a control (Con), normal manure (NM), composted manure (CM), and acidified manure (AM), were applied under saline soil (EC 8.00 dS m−1) and non-saline soil (EC 1.48 dS m−1) conditions along with two levels of Zn, including Zn at 0 kg ha−1 (native soil Zn = 2.2 mg kg−1) and Zn at 25 kg ha−1 (62.2 mg Zn kg−1 soil was achieved). The AM was prepared by adding sulfur and sulfur-oxidizing bacteria to the composted manure. All the manures were applied at 1% (w/w), and ZnSO4 (33% Zn) was used as a Zn source. Lentil variety Masoor 2021 was cultivated as a test crop in five replications of each treatment arranged in a completely randomized design. Applying AM with Zn considerably increased the lentils' growth, yield, and Zn content under saline and non-saline conditions. Under non-saline soils, the treatment of AM + Zn significantly promoted the Zn content in the root (132.5%), shoot (91.7%), grain (49.1%), root length (79.7%), plant height (33.7%), and SPAD value (29.9%). Under saline conditions, application of AM + Zn promoted uptake of Zn in the root (218.5%), Zn content in the shoot (175.7%), Zn accumulation in the grain (107.7%), root length (109.7%), plant height (37.8%), and SPAD value (52.8%) compared to the control. According to the results, lentils should be grown with AM and Zn to increase their growth, yield, and Zn content significantly. This is a cost-effective and sustainable way to combat Zn deficiency in lentils. [ABSTRACT FROM AUTHOR]

Salinity is one of the main factors causing soil deterioration, making it unsuitable for agriculture. It is well documented that the application of halotolerant and halophilic plant growth-promoting bacteria (PGPR: plant growth-promoting rhizobacteria) with biological control activities as an inoculant of cultivated plants offers a biological alternative to the use of agrochemicals, particularly when subjected to salt stress. From this perspective, 70 bacterial strains were isolated from saline soils (sebkha) in arid and semi-arid areas of Eastern Algeria. Three isolates were selected based on their ability to produce bioactive molecules allowing them to promote plant growth, such as hydrolytic enzymes, indole acetic acid (auxin-phytohormone), HCN, NH3, etc. Two of these isolates belonged to the genus Serratia and the third was a halophilic Halomonas bacteria. These bacteria were identified based on their 16S rDNA sequences. Antagonism tests against phytopathogenic fungi were carried out. The identification of the antifungal molecules produced by these bacteria was determined using high-performance liquid chromatography. These bacteria can inhibit mycelial development against phytopathogenic fungi with rates reaching 80.67% against Botrytis cinerea, 76.22% against Aspergillus niger, and 66.67% against Fusarium culmorum for Serratia sp. The strain Halomonas sp. inhibited mycelial growth through the production of volatile substances of Aspergillus niger at 71.29%, Aspergillus flavus at 75.49%, and Penicillium glabrum at a rate of 72.22%. The identification of the antifungal molecules produced by these three bacteria using HPLC revealed that they were polyphenols, which makes these strains the first rhizobacteria capable of producing phenolic compounds. Finally, pot tests to determine the effectiveness of these strains in promoting wheat growth under salinity stress (125 mM, 150 mM, and 200 mM) was carried out. The results revealed that a consortium of two isolates (Serratia sp. and Halomonas sp.) performed best at 125 mM. However, at higher concentrations, it was the halophilic bacteria Halomonas sp. that gave the best result. In all cases, there was a significant improvement in the growth of wheat seedlings inoculated with the bacteria compared to non-inoculated controls. [ABSTRACT FROM AUTHOR]

Salt stress seriously hinders the normal growth of plant seedling roots. Magnesium, as one of the essential medium elements for plant growth, can effectively alleviate the damage of salt stress to plant roots, but the key genes involved and their mechanism are still unclear. The purpose of this study was to explore the related molecular mechanism of exogenous magnesium regulating cation homeostasis in peanut seedlings under salt stress. Firstly, according to plant physiology experiments, it was found that exogenous magnesium treatment significantly improved the tolerance of peanut seedlings to salt stress. After that, the transcriptome data were integrated, and further gene expression analysis showed that the expression of genes such as CNGC1, NCLs, and NHX7 was regulated under exogenous magnesium treatment, which effectively reduced the accumulation of sodium ions in cells. At the same time, exogenous magnesium also regulates the expression of genes such as ACAs and POTs and maintains the homeostasis of calcium and potassium ions in cells. These results reveal the molecular mechanism of exogenous magnesium regulating the cation homeostasis of peanut seedlings under salt stress, which provides an important reference for further revealing the key genes of salt tolerance in plants. [ABSTRACT FROM AUTHOR]

Soil salinization is a primary environmental factor leading to reduced crop yields, and oil shale waste residues may have the potential to alleviate plant salt stress. This study aims to investigate the effects of three types of oil shale waste residues (fine concentrate ore, fine ore, and semi-coke) on the growth and physiological characteristics of maize seedlings in saline–alkali soil. The results indicate the following: (1) All three types of oil shale waste residues increased the root vitality of seedlings and reduced the root proline content. (2) The three types of oil shale waste residues increased the activity of superoxide dismutase (1.70% to 97.19%) and peroxidase (29.39% to 61.21%) in maize seedlings, but there were differences in their effects on catalase activity. The fine ore and semi-coke treatments increased catalase activity (4.98% to 77.42%), while fine concentrate ore decreased catalase activity (39.28% to 5.30%). (3) The three types of oil shale waste residues effectively alleviated the degree of membrane lipid peroxidation in maize seedling leaves. (4) Principal component analysis showed that the semi-coke treatment was beneficial to the growth and physiology of maize seedlings in saline–alkali soil, with the optimal effect occurring at a 0.2% addition rate. In conclusion, adding semi-coke to saline–alkali soil promotes the growth of maize by regulating its physiological and biochemical mechanisms, alleviating the salt stress on maize seedlings caused by salt content. [ABSTRACT FROM AUTHOR]

Salinity is a prominent environmental stressor that significantly impacts plant growth and development. Here, we conducted research on the physiological and transcriptomic mechanism of a wild cucumber, Cucumis hystrix Chakr, under NaCl stress. Physiological data showed that contents of malondialdehyde, peroxide (H2O2), proline, soluble sugar, and activities of antioxidant enzymes of superoxide dismutase, peroxidase, ascorbate peroxidase, and glutathione reductase in wild cucumber plants were increased significantly after NaCl treatment. Transcriptomic analysis revealed that 3509 transcripts were differentially expressed in leaves and 5516 transcripts in roots after NaCl treatment. Numerous genes were related to the signal transduction, transcription factor, ion transport, osmotic metabolism, and reactive oxygen species scavenging. Moreover, the thioredoxin H type gene of Cucumis hystrix Chakr (ChTrxh) was isolated and characterized. Our study demonstrated that the transgenic tobacco plants overexpressing ChTrxh exhibited enhanced tolerance to NaCl stress compared to wild-type plants. These findings contribute valuable insights into the functional characteristics of important genes in wild cucumber under NaCl stress. [ABSTRACT FROM AUTHOR]

Germination events of plants often occur after rainfall in saline environments where the soil salinity is diluted, viz recovery germination. Previous germination studies have rarely considered the duration of exposure to salt stress, and none of them have investigated recovery germination under low-salt concentration, other than in distilled water. The main objective of this study was to investigate the effects of salinity, exposure duration and low-salt recovery solutions on seed germination of the weed Chenopodium acuminatum to get a clear insight about the germination strategy exhibited by this species in a saline habitat. Seeds were initially exposed to 0–400 mM NaCl for 10, 20 and 30 d. The subsequent recovery experiment was conducted differently. For those initially treated with 100 and 200 mM NaCl, the recovery solution was distilled water, while for those initially treated with 300 and 400 mM NaCl, the recovery solution was distilled water, at 50 and 100 mM NaCl. Results showed that the recovery germination percentage and rate significantly decreased when the exposure duration extended. Seeds could subsequently recover to germinate at high percentages at recovery salt solution concentrations for a short duration, but the recovery percentages and rates in high salinity, combined with high exposure duration and relatively high recovery salt concentrations, were remarkably lower. More than 30% of the ungerminated seeds were viable after the recovery experiment. We suggest that Ch. acuminatum exhibits a 'cautious' strategy of germination to avoid injury from long-term salt stress and ensure survival for the subsequent continuation of its population under unfavorable saline conditions. [ABSTRACT FROM AUTHOR]

Soil salinization is a significant obstacle to improving natural grasslands, also affecting farmland productivity. The main distribution area of high salinity soils is primarily located in western China, with a significant presence in the Qinghai–Tibet Plateau (QTP). Siberian wildrye (Elymus sibiricus L.) has been widely used in ecological restoration and reseeding in the QTP, due to its strong salt and alkali resistance. To comprehensively evaluate its salt tolerance and to screen salt-tolerant and salt-sensitive germplasm resources, 50 wild E. sibiricus accessions were assessed through the measurement of several physiological parameters. These included the relative water content (RWC); relative electrical conductivity (REC); malondialdehyde content (MDA); proline content (Pro); and Na+/K+ ratio after 14 days of salt stress treatment (200 mmol L−1 NaCl). Through principal component analysis (PCA) based on both material sources and physiological indexing, it was found that the salt damage score (SDS) and RWC had a strong positive correlation (p < 0.05), in opposition to other indices. The positive indicators were REC, Pro, Na+/K+, and MDA, and the negative indicators were RWC and SDS. Ultimately, by combining the results of the conventional membership function analysis and the weighted membership function analysis based on major components, three salt-tolerant accessions—including XJ013-28, NM021-13 and XJ012-17—and four salt-sensitive accessions, including XZ008-20, QH013-8, XZ009-20, and QH005-35, were screened out. These results could be effectively used to assess the effects of salt stress on Siberian wildrye and its related species. This study provides a reference for the discovery and breeding of salt-tolerant cultivars among the Elymus species. [ABSTRACT FROM AUTHOR]

In saline and salinity-affected soils, the global productivity and sustainability of cotton are severely affected by soil salinity. High salt concentrations hinder plant growth and yield formation mainly through the occurrence of osmotic stress, specific ion toxicity, and nutritional imbalance in cotton. A number of agronomic practices have been identified as potential solutions to alleviate the adverse effects induced by salinity. While genetic breeding holds promise in enhancing the salinity tolerance of cotton, agronomic practices that improve the root zone environment, ameliorate soil conditions, and enhance salinity tolerance are currently considered to be more practical. This compressive review highlights the effectiveness of agronomic practices, such as furrow seeding, plastic mulching, their combination, densely planting, and the appropriate application of fertilizer and plant growth regulators, in mitigating the negative impact of salinity on cotton. By implementing these agronomic practices, cotton growers can improve the overall performance and resilience of cotton crops in saline and salinity-affected soils. This review provides valuable insights into practical agronomic measures that can be adopted to counteract the adverse consequences of soil salinity on cotton cultivation. [ABSTRACT FROM AUTHOR]

Soil salinity poses a significant challenge to plant growth and agricultural productivity. Research demonstrated the potential of exopolysaccharides (EPS) to enhance plant growth and improve resistance to abiotic stress. Nevertheless, the precise regulatory mechanism by which EPS mediates salt tolerance in alfalfa (Medicago sativa) remains largely unexplored. To investigate the protective effects of EPS from Erwinia persicina Cp2 in enhancing salt stress tolerance in alfalfa, a hydroponic experiment was conducted on the 'Aohan' cultivar of alfalfa, and changes in germination rate, biomass, chlorophyll content, electrolyte leakage (EL), hydrogen peroxide (H2O2), malondialdehyde (MDA), proline (Pro), soluble sugar (SS), soluble protein (SP), and activities of superoxide dismutase (SOD) and peroxidase (POD) were analyzed with and without Cp2 EPS under 75 mmol/L NaCl conditions. The results show that the exposure of alfalfa to salt conditions seriously inhibited its germination and growth. However, it is interesting that the application of Cp2 EPS greatly alleviated the damage of salt stress on alfalfa and promoted the germination of alfalfa as well as the root length, seedling length, fresh weight, and dry weight of the plants. In addition, the increases in MDA, H2O2 content, and EL rate caused by salt stress were inhibited after Cp2 EPS treatment, while chlorophyll, Pro, SP, and SS contents as well as SOD and CAT activities were increased. Therefore, Cp2 EPS can significantly alleviate the toxic effect of 75 mmol/L NaCl stress on alfalfa, and comprehensive analysis shows that 1.5 g/L Cp2 EPS had the best alleviating effect on alfalfa at this salt stress concentration. This study lays a practical and theoretical foundation for the development of biogenic agents used to alleviate the growth of alfalfa in saline alkali soil. [ABSTRACT FROM AUTHOR]

Kenaf is one of the most important natural cannabis plants. Molecular marker-assisted breeding is vital for accelerating the breeding process of kenaf. However, the number of kenaf markers is insufficient for molecular marker-assisted breeding. Using transcriptome sequencing data for salt-stressed kenaf plants, the number and distribution of simple sequence repeats (SSRs) and single nucleotide variations (SNVs) in the expressed sequences were determined. The objectives of this study were to elucidate the sequence variations in kenaf genes expressed in response to salt stress and to identify stable and dependable molecular markers. Primers were designed for SSR loci and then EST-SSR molecular markers were generated. The subsequent analyses revealed that 30.50% of the unigenes contained SSR motifs, most of which were single nucleotides followed by trinucleotides and dinucleotides. The unigenes containing SSRs were mostly associated with kenaf salt tolerance. Additionally, 10,483 SNVs were detected in contig sequences. Of the 3995 differentially expressed genes encoding interacting proteins, 1297 contained SSRs. Most of these genes were associated with metabolic pathways (e.g., 03000 transcription factors, B09132 signal transduction, and 04122 sulfur relay system). We designed 20 pairs of EST-SSR primers to genotype 30 kenaf varieties (lines), of which 9 primer pairs were ideal for genotyping (e.g., 1 highly polymorphic marker and 2 moderately polymorphic markers). The primer pairs designed for the EST-SSR markers in the kenaf genome may be useful SSR molecular markers for future research on kenaf. The verified polymorphic markers may be applicable to the molecular marker-assisted breeding of salt-tolerant kenaf varieties. [ABSTRACT FROM AUTHOR]

Phosphorus (P) management in wheat grown under saline soil conditions requires a better understanding of how P placement and salt stress affect spatial root distribution, plant agronomic performance, and nutrient utilization. A column culture experiment was conducted with two wheat genotypes, Alice and LX99, five P placements ('Top Dressed High P', TopHP; 'Top Dressed Reduced P', TopRP; 'Deep Banded High P', DeepHP; 'Deep Banded Reduced P', DeepRP; and 'No P added', −P), and two salt stress levels ('salt stress', +S; 'non-salt stress', −S) to investigate differences in biomass accumulation, nutrient utilization, and root distribution (0–20 cm, 20–40 cm, and 40–100 cm) among treatments. Deep P placement under non-salt stress increased root distribution at 20–40 cm soil depth for both genotypes compared to top P placement. P application under salt stress increased root weight at all three soil depths in both genotypes and P accumulation in aboveground plant parts (except for LX99 under TopRP). The highest P utilization efficiency occurred in Alice with TopRP and in LX99 with DeepRP under non-salt and salt stresses. Overall, a coordinated adaptation in allocating biomass between belowground and aboveground plant parts, along with altered nutrient utilization, was necessary to reach a growth compromise in response to P supply changes and salinity. Therefore, genotype, P placement depth, and soil salinity should be considered to improve wheat P utilization efficiency under saline conditions. [ABSTRACT FROM AUTHOR]

Plant growth and production are more severely inhibited by alkalinity than by salinity. However, the metabolites responsible for the reduced growth caused by alkalinity are largely unknown. Here, the Illumina RNA-Seq analysis and targeted metabolome were used to identify the differentially expressed genes and metabolites responding to salt and alkali stresses. The expression levels of eight genes related to photosynthesis and some genes related to chlorophyll synthesis decreased under alkali stress, whereas no changes were detected under salt stress, which may explain the observed lower level of photosynthetic rate in alkalinity than in salinity. Under alkali stress, significant decreases in the relative abundances of cis-cinnamic acid and scopoline were observed, which correlated with the high levels of reactive oxygen species (ROS). The levels of protocatechuic acids decreased, correlating with the observed decrease in the chlorophyll content. Alkalinity markedly increased the production of o-coumaric acid, which contributes to growth inhibition. No significant changes in cis-cinnamic acid, scopoline, and o-coumaric acid were detected in salinity, which may be the reason for the stronger growth inhibition due to alkali stress than salt stress. The accumulation of citric acid, serotonin, pyroglutamic acid, L-citrulline, ferulic acid, and caffeic acid was detected under salt and alkali stress conditions, indicating high free radical scavenging capacity. The enhancement of mevalonic acid and salicylic acid levels was detected under alkali stress, which could have facilitated chlorophyll accumulation. Salt and alkali stress conditions also led to the accumulation of cyclic AMP related to inorganic ion regulation and betaine-related osmoregulation. Benzamide, phenethylamine, N-feruloyltyramine, chrysoeriol 6-C-hexoside, 1,3-o-di-p-coumaroyl glycerol, cordycepin, and 1-o-p-cumaroylglycerol were identified to be accumulated in response to alkali stress. [ABSTRACT FROM AUTHOR]

As an excellent grafting material, Malus baccata (L.) Borkh is native to Liaoning, Jilin, Heilongjiang and other regions in China, with a strong adverse environmental adaptability. As a typical transcription factor, the NAC gene acts as a regulator in many molecular pathways responding to abiotic stress. However, research of NAC in the Malus baccata has just begun. In the present research, a new NAC transcription factor, MbNAC22, was obtained from the seedlings of Malus baccata, and its function in drought and salt treatments was studied by heterologous expression. The open reading frame of the MbNAC22 gene is 768, encoding 255 amino acids (aa). Through confocal microscopy, MbNAC22 was found to be located in the nucleus. The heterologous expression of MbNAC22 in Arabidopsis showed that it enhanced the viability of Arabidopsis under drought and salt treatments. Under stresses, the chlorophyll content of the plants decreased, but the decline of the overexpressed-MbNAC22 Arabidopsis was relatively low. Through phenotypic observation and determination of stress-related physiological indicators, it was found that compared with WT Arabidopsis, overexpressed-MbNAC22 Arabidopsis had a higher tolerance to stresses. Under stresses, the overexpression of MbNAC22 positively regulated ion-transport-related genes (AtNHX1 and AtSOS1), the key genes of the ABA pathway (AtNCED3 and AtDREB2A), the proline synthesis gene (AtP5CS2) and the drought-induced gene (AtERD11), while the expression of the leaf senescence-associated gene (AtSAG21) and programmed cell death related gene (AtAEP1) was inhibited. Therefore, we speculate that MbNAC22 responds positively to drought and salt stresses by regulating the expression of stress-related genes. [ABSTRACT FROM AUTHOR]

MYB (v-MYB avian myeloblastosis viral oncogene homolog) transcription factor (TF) family has numerous members with complex and diverse functions, which perform an integral role in regulating the plant's response to adversity. This study used cloning to obtain a novel MYB TF gene from the diploid strawberry Fragaria vesca, which was given the designation FvMYB44. Subcellular localization results showed that the protein of FvMYB44 was a nuclear localization protein. The resistance of Arabidopsis thaliana to salt and low temperature stresses was greatly enhanced by the overexpression of FvMYB44. When subjected to salt and temperature stress, transgenic plants showed higher proline and chlorophyll concentrations and higher superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities than wild-type (WT) and unloaded line (UL) of A. thaliana. In contrast, WT and UL lines had higher malondialdehyde (MDA) content and reactive oxygen species ROS (O2− and H2O2) content. These findings suggest that FvMYB44 may perform a role in controlling the response of A. thaliana to cold and salt stress. [ABSTRACT FROM AUTHOR]

Myelocytomatosis (MYC) transcription factors are crucial mediators of the jasmonate signaling pathway, which mediates the growth and developmental processes of plants. However, the function of MYC genes in tomato, Solanum lycopersicum (SlMYC), remains poorly understood. In this study, we have identified 14 non-redundant SlMYC genes across the genome of tomatoes. Six of the twelve chromosomes included these genes, and four syntenic pairs of SlMYC were identified. According to the results of phylogenetic analysis, 14 SlMYC genes were clustered into classes I, II, III, and IV, and their functional domains were predicted. The SlMYC upstream promoter region contained a variety of light-, stress-, and hormone-response regulatory elements. The expression of the 14 SlMYC genes differed significantly across organs. SlMYCs primarily showed an upregulation trend after methyl jasmonate (MeJA) treatment. In contrast, after treatment with sodium chloride (NaCl), SlMYCs showed a trend of downregulation. However, there were differences in the expression patterns of SlMYCs after mannitol treatment. Using clustered regularly interspaced short palindromic repeats/Cas 9 (CRISPR/Cas 9) technology, the loss-of-function of SlMYC1 (slmyc1) was obtained. The slmyc1 tomato plants demonstrated reduced resistance to NaCl and mannitol stress compared to wild-type plants due to their shorter root length and higher reactive oxygen species (ROS) content. In brief, this study provides valuable information about the taxonomy of the SlMYC genes in tomato. It establishes a foundation for future research on the mechanism by which SlMYC influences plant development and stress response. [ABSTRACT FROM AUTHOR]

To clarify the effect of tillage methods on saline–alkali land improvement and maize growth in cropland salinized to different degrees, we set up two treatments (shallow rotation (15 cm depth; CK) and deep straw return (35 cm depth; DPR)) in land characterized by three different salinization degrees and analyzed the effects of the two treatments on soil nutrient content, salinity index, chlorophyll fluorescence, growth status, and yield at three salinization levels. The results show that (1) compared with CK, alkaline N, total N, Olsen P, exchangeable K, and organic matter in saline soils were all significantly improved, and total salt and pH values were reduced by 34.01–50.79% and 2.56–7.54%, respectively, under deep straw return conditions, representing the largest values in moderately saline–alkali land. (2) Compared with CK, chlorophyll fluorescence was significantly improved, and maximum photochemical efficiency (Fv/Fm), photochemical quenching (qP), and effective quantum yield of PSII (ΦPSII) were significantly increased by 8.09–15.41%, 9.13–17.93%, and 38.79–70.83% following deep straw return treatment; these increases were the largest ones observed in moderately saline–alkali land. (3) Deep straw return promoted the growth of maize and significantly increased the yield of maize. Plant height, leaf area index, and yield increased the most in moderately saline–alkali land and increased by 6.84–21.79%, 0.59–2.28 units, and 12.78–28.07%, respectively. The yield increased by 33.89 %, which was mainly due to the increase in 1000-grain weight. The results provide a theoretical basis for taking straw return measures to improve soil and increase maize yield in saline–alkali land. [ABSTRACT FROM AUTHOR]

Selenium (Se) plays several significant roles in regulating growth, development and plant responses to various abiotic stresses. However, its influence on sulfate transporters (SULTRS) and achieving the harmony with other salt-tolerance features is still limited in the previous literatures. This study elucidated the effect of Se supplementation (5, 10 and 20 µM) on salt-stressed (50 mM NaCl) snap bean seedlings. Generally, the results indicated that Se had dual effects on the salt stressed seedlings according to its concentration. At a low level (5 µM), plants demonstrated a significant improvement in shoot (13.8%) and root (22.8%) fresh weight, chlorophyll a (7.4%), chlorophyll b (14.7%), carotenoids (23.2%), leaf relative water content (RWC; 8.5%), proline (17.2%), total soluble sugars (34.3%), free amino acids (FAA; 18.4%), K (36.7%), Ca (33.4%), K/Na ratio (77.9%), superoxide dismutase (SOD; 18%), ascorbate peroxidase (APX;12.8%) and guaiacol peroxidase (G-POX; 27.1%) compared to the untreated plants. Meanwhile, most of these responses as well as sulfur (S), Se and catalase (CAT) were obviously decreased in parallel with increasing the applied Se up to 20 µM. The molecular study revealed that three membrane sulfate transporters (SULTR1, SULTR2 and SULTR 3) in the root and leaves and salinity responsive genes (SOS1, NHX1 and Osmotin) in leaves displayed different expression patterns under various Se treatments. Conclusively, Se at low doses can be beneficial in mitigating salinity-mediated damage and achieving the functioning homeostasis to tolerance features. [ABSTRACT FROM AUTHOR]

Wheat is affected by various biotic and abiotic stresses, especially salinity, which reduces the growth and yield drastically. With this view, an experiment was conducted to observe genotypic differences in agro-morphological, yield, and biochemical responses to salinity. Experimental variables consisted of five salt-tolerant genotypes (G 13, G 20-1, G 9, G 22, G 20-2), one susceptible genotype (G 24) and one standard check variety (BARI ghom 25), which assigned to four levels of salinity with electrical conductivities 0, 4, 8 and 12 dS m−1. Irrespective of genotypes, salinity stress significantly decreased the yield and yield attributes. However, maximum total tillers plant−1, effective tillers plant−1, number of grains spike−1, and grain yield plant−1 was found in salt tolerant genotype G 20-2, followed by genotypes G 13, G 20-1, and the lowest was observed in salt-susceptible genotype G 24. The lowest reduction percentage of yield and yield attributes were also observed in salt tolerant genotype G 20-2 followed by genotypes G 13, G 20-2, and the maximum reduction percentage was found in salt-susceptible genotype G 24. Results showed that the highest amount of proline, glycinebetaine, soluble sugar and soluble protein content were observed in salt-tolerant genotype G 20-2, followed by genotypes G 13, G 20-1, and the minimum was found in salt-susceptible genotype G 24. On the other hand, the lowest hydrogen peroxide (H2O2) and melondealdehyde (MDA) accumulation was detected in the same salt-tolerant genotype G 20-2, followed by G 13, G 20-1, and the maximum was observed in salt-susceptible genotype G 24. Therefore, higher accumulations of compatible solute in the tolerant genotypes reduce the oxidative stress, and provide the higher yield. [ABSTRACT FROM AUTHOR]

Previous researchers have focused on the role of 24-epibrassnolide (EBR) in alleviating stresses in plants, whereas the effect of EBR on rice grain yield formation from the perspective of the whole growth stage remains less concerned. To further confirm the optimal application concentration and application periods of EBR in rice (Oryza sativa L.) under salt stress, a seed germination experiment, a seedling experiment, and a pot experiment were designed and conducted. Results showed that EBR treatment significantly enhanced germination indicators and seedling morphological traits, and the effects varied among different EBR concentrations, which were 0.5 > 1.0 > 0.1 > 0.05 mg L−1. Under 0.5% salt treatments, 0.5 mg L−1 EBR spraying significantly enhanced the seedling height, root length, above-/under-ground fresh weight, and above-/under-ground dry weight by 9.2%, 15.9%, 48.0%, 19.5%, 29.3%, and 12.5%, respectively. The spraying of EBR at different periods enhanced rice yield by 6.7% to 94.4% under salt stress. The relatively higher panicle number (increased by 42.9%) and spikelet number per panicle (increased by 96.1%) were the main reason resulting in higher grain yield under the S+T5 (EBR sprayed at both transplanting and heading stage) treatment. Compared to those under S treatment, catalase (CAT) activity was significantly enhanced by 25.0%, while malondialdehyde (MDA) content was dramatically decreased by 37.3% under the S+T5 treatment. The S+T5 treatment significantly enhanced the K+ content in rice root and leaf and decreased the Na+ content in rice root (by 30.4%), thereby leading to higher K+/Na+ under salt stress. The current study concluded that 0.5 mg L−1 was the optimal concentration of EBR in alleviating the adverse effect of salinity. Spraying (transplanting + heading) of EBR twice displayed the best alleviating effect under salt stress, which was realized through enhanced antioxidant enzyme, higher K+ maintenance in leaves, and lowered absorption of Na+ in rice root. [ABSTRACT FROM AUTHOR]

Vicia villosa Roth is an annual cover crop that is widely grown in orchards in China. Information on seed ecology is valuable as it helps famers to plant cover crops and manage other weed species in agricultural practice; however, information on V. villosa seed-germination ecology is limited. Thus, this study investigated the seed germination and seedling emergence of V. villosa under various temperatures, photoperiods, levels of salt stress, pH, levels of osmotic stress, and burial depths. The results showed that the germination values of the V. villosa seeds were greater than 93% at the constant temperature range of 5–30 °C and fluctuating temperatures of 5/15 °C–20/30 °C; in particular, the germination of the seeds peaked 20 °C and 15/25 °C, with germination values of 95% and 94.5%, respectively. Light was not necessary for the V. villosa seeds' germination. When the pH was in the range of 5–10, the germination values of the V. villosa seeds fluctuated between 85% and 94%, and obvious inhibition of germination was observed at pH = 4, with a germination value of 15%. The Vicia villosa seeds exhibited obvious salt tolerance, and the seed-germination value was still greater than 50% when the salt concentration reached 280 mM. The seeds were relatively sensitive to osmotic stress, and the germination value was lower than 50% when the osmotic potential was −0.5 MPa. In addition, the germination value of the seeds peaked when the seeds were 1–2 cm underneath the ground; in particular, the seeds still germinated and emerged when the seeds were buried in soli at a depth of 10 cm. These results confirmed that V. villosa, as a cover crop, has considerable potential to be planted and grown in orchards in China and, furthermore, that it may contribute to early weed management in fields, supporting the establishment of V. villosa populations. [ABSTRACT FROM AUTHOR]

Fungal endophytes are not widely known for their role in bioactive metabolite production and salinity stress alleviation in different crop plants. Presently, we investigated the salt stress (NaCl, KCl, and H2SO4) mitigation capabilities of fungal endophyte Candida membranifaciens (FH15) isolated from Euphorbia milii L. The pure culture filtrate (CF) of C. membranifaciens revealed siderophore production and solubilization of phosphate, with high levels of indoleacetic acid (IAA: 35.8µg/mL), phenolics (70 µg/mL), and flavonoids (50 µg/mL) by using a UV spectrophotometer. The LC/MS analysis of the CF showed different phenols and flavonoids that were identified as Salicylic acid, Baicalein, Aconitic acid, Feruloylquinic acid, Coniferyl aldehyde hexoside, Pentose, Chlorogenic acid, Myricetin, Propoxyphene, and Amino-flunitrazepam. Inoculation of maize seedlings with C. membranifaciens significantly (p = 0.05) enhanced the fresh and dry biomass, carotenoid, and chlorophyll contents under 100 mM salt stress conditions. Similarly, the catalase, peroxidase activity, phenols, proline flavonoids and relative water contents (RWC) of the maize plants were enhanced. More interestingly, the inoculation of C. membranifaciens on maize revealed a higher endogenous IAA level as compared to non-inoculated control plants. Endophyte C. membranifaciens inoculation on maize seedlings under salt stress revealed a 20.87% and 16.60% increase in fresh and dry biomass, as well as significantly enhanced root shoot length and allied growth attributes, in addition to an alleviation of the adverse effects of salinity stress. Conclusively, endophytic C. membranifaciens significantly enhanced the growth attributes of maize and mitigated the adverse effects of salinity stress. Such endophytic fungal strain could be used for further field trails to enhance agricultural productivity and facilitate sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

Salinity causes significant agricultural losses in many areas in the world. Plant growth promoting bacteria (PGPB) are a promising solution to enhance plant growth and productivity under such stress conditions by different mechanisms, mainly phosphorous solubilization. This study aims to improve wheat seedling growth under salt stress by a halotolerant phosphorous-solubilizing bacterial strain. Soil sample was collected in the south of Algeria (Ghardaia), and bacterial isolation was carried out on nutrient agar (NA) at different NaCl concentrations (300; 600 and 900 mM). The ability of the halotolerant isolates to solubilize inorganic phosphorous at 0; 300; 600 and 900 mM NaCl was determined. The isolate that showed the highest solubilization indexes was selected and identified as Pseudomonas azotoformans. Sterile wheat (Triticum aestivum) seeds were inoculated by this strain and then sown in soil at different NaCl concentrations (0; 100; 200; 300 mM). Different growth parameters were measured after 15 days. The strain showed its highest capacity for phosphorous solubilization (255.152 ± 0.01 µg/mL) at 300 mM NaCl, and for phytate mineralization (0.168 ± 0.002 U/mL) at 100 mM NaCl. The highest amount of soluble phosphorous in the soil was 49.42 ± 0.36 ppm obtained at 100 mM NaCl. Seed germination percentage, shoot and root length and fresh and dry weights were found to be higher in bacterial inoculated seedlings compared to uninoculated ones. According to this study, the use of plant growth promoting bacteria represents an important biotechnological approach to restore phosphorous levels in saline soils and to promote plant growth in salt-affected agricultural land. [ABSTRACT FROM AUTHOR]

Although the use of marginal-quality water can be an effective measure to alleviate water scarcity, it often contains a high concentration of salts that can compromise crop growth. As a result, farmers apply more water than necessary to leach salts away from the root zone, resulting in wasted water and the release of fertilizers into the groundwater. In this study, we assessed the effects of three salinity levels of irrigation water (1.8 dS m−1, 3.3 dS m−1, and 4.9 dS m−1) on the physiology and ornamental traits of Hebe andersonii cv. Variegata. The experiment was carried out with potted plants in a greenhouse for seven months. We also studied the feasibility of growing this cultivar without leaching salts. The results showed that Hebe plants can be grown without leaching using water up to 3 dS m−1. This setup produces plants with high water use efficiency and without reducing their ornamental value. Meanwhile, irrigation with 5 dS m−1 water reduced the quality of Hebe but did not compromise its physiological processes. The photosynthesis of Hebe under salinity conditions was mainly controlled by stomata, which was related to the level of salt stress and water status of the plant. Salinity had no significant effects on photosystem II, which can be explained by the fact that Hebe was able to dissipate the excess excitation energy as heat effectively. Hebe was able to avoid ion toxicity and maintain a suitable nutrient balance under the salinity levels tested in this experiment. [ABSTRACT FROM AUTHOR]

Thioredoxin (TRX) is a small molecule protein that participates in the redox process and plays a decisive role in various functions of plants. However, the role of TRX in Medicago sativa (alfalfa), a widely cultivated perennial herb of legume, is still poorly understood. Here, we isolated MsTRX from alfalfa and determined the characteristics in improving salt tolerance by assaying the phenotype and physiological changes and the expression of stress-response genes in transgenic tobacco. The expression of MsTRX was similar in alfalfa roots, leaves, and inflorescences, and was downregulated in response to cold, drought, and salt treatment. The overexpression of MsTRX in tobacco promoted the accumulation of soluble sugar (SS) and proline; enhanced the activity of peroxidase (POD); and induced the upregulation of beta-amylase 1 (BAM1), lipid-transfer protein 1 (LTP1), candidate signal molecules/sensor relay proteins (CBSX3), superoxide dismutase [Cu-Zn] (Cu/Zn-SOD), superoxide dismutase [Mn] (Mn-SOD), protein gamma response 1 (GR1), dehydrin DHN1-like (ERD10B), and serine/threonine-protein kinase (SnRK2), as well as the downregulation of phyB activation-tagged suppressor1 (BAS1) and serine/threonine-protein kinase that phosphorylates LHCII protein 7 (STN7) under salt stress. These results indicated that MsTRX improves salt tolerance via maintaining osmotic homeostasis, scavenging reactive oxygen species (ROS), and regulating the transcription of stress-response genes in plants. In our study, we provided a new understanding of how MsTRX improves salt stress in plants and how MsTRX can be included in future breeding programs to improve salt tolerance in alfalfa. [ABSTRACT FROM AUTHOR]

Soybean [Glycine max (L.) Merri.] is an important oilseed and food crop. In recent years, environmental degradation has accelerated soil alkalization, salinization, and water deficit, which have seriously threatened the soybean quality and yield. Chaperone DNAJ proteins play important roles in plant response to a number of abiotic and biotic stresses. Here, we investigated the function of a soybean DNAJ gene, GmDNAJC7, in plant tolerance to abiotic stresses. GmDNAJC7 gene expression was induced by alkaline-salt, salt, and drought treatments in soybean roots, suggesting its possible role in soybean response to these stresses. GmDNAJC7 overexpression improved the alkaline-salt tolerance of soybean composite plants, which showed a higher SPAD (Soil and Plant Analysis Development) value for chlorophyll content and leaf relative water content than the control plants after NaHCO3 treatment. Moreover, the GmDNAJC7 overexpressing Arabidopsis had a higher germination rate and average root length than the wild type and dnajc7 mutant, under NaHCO3, NaCl, and mannitol stresses, indicating that the ectopic expression of the GmDNAJC7 gene enhanced the alkaline-salt, salt, and drought tolerance in Arabidopsis. These findings suggest that GmDNAJC7 is involved in the alkaline-salt, salt, and drought tolerance in Arabidopsis and soybean. This study provides new insights into the role of DNAJ proteins in plant tolerance to abiotic stress. [ABSTRACT FROM AUTHOR]

Soil salinization is a worldwide problem affecting agriculture and the environment. Utilizing saline land by screening and cultivating salt-tolerant crops is an economical and ecological solution. Leaf beet (Beta vulgaris var. cicla) is an important vegetable resource and has certain salt tolerance, but what concentration it can tolerate still remains to be verified. Hence, this work explored the adaptability of leaf beet to salt stress. A soil culture experiment was conducted. By adding NaCl to the soil, the concentrations of 0% (S0), 0.3% (S3), 0.5% (S5) and 0.7% (S7) NaCl salinity were set to analyze the changes of leaf beet growth (plant height, leaf number and biomass); leaf morphology (leaf area, shape, leaf mass per area (LMA) and tissue density); and leaf physiology (chlorophyll content, leaf relative water content (LRWC), water content at saturation (WCS), water saturation deficit (WSD) and succulence). The results showed that 0.3% NaCl salinity increased LMA and decreased biomass, while the rest were almost the same as the control (S0). Under 0.5% and 0.7% NaCl salinity, LRWC decreased significantly, while WCS and WSD increased significantly. Under such salt stress, the leaf beet adapted by reducing plant height, delaying the engendering of new leaves, decreasing leaf area, changing leaf shape, maintaining high chlorophyll content, and increasing LMA, tissue density and succulence. With these strategies, the leaf beets survived under salt stress up to 0.7% NaCl salinity with a certain biomass, providing a meaningful exploration for the multi-purpose planting and application of leaf beets on saline soils. [ABSTRACT FROM AUTHOR]

Improving rice salt-tolerance is an effective way to deal with the increasing food demand caused by soil salinization and population growth. Nevertheless, the molecular mechanisms of rice salt-tolerance remain elusive. In this study, comparative transcriptomic analyses were performed to identify salt-tolerance genes that were either specifically regulated or more changed in salt-tolerant cultivar FL478 relative to salt-sensitive cultivar 93-11. In total, 1423, 175, and 224 salt-tolerance genes were identified under 200 mM NaCl treatment for 6 h, 24 h, and 72 h, respectively. These genes were commonly enriched in transport and peroxidase/oxidoreductase activity across all timepoints, but specially enriched in transcription regulator activity at 6 h under salt stress. Further analysis revealed that 53 transporters, 38 transcription factors (TFs), and 23 reactive oxygen species (ROS) scavenging enzymes were involved in salt adaptation of FL478, and that overall, these salt-tolerance genes showed a faster transcriptional expression response in FL478 than in 93-11. Finally, a gene co-expression network was constructed to highlight the regulatory relationships of transporters, TFs, and ROS scavenging genes under salt-stress conditions. This work provides an overview of genome-wide transcriptional analysis of two contrasting rice genotypes in response to salt stress. These findings imply a crucial contribution of quickly transcriptional changes to salt tolerance and provide useful genes for genetic improvement of salt tolerance in rice. [ABSTRACT FROM AUTHOR]

The effect of seed coating salt-stressed tomato with the bacterium Achromobacter xylosoxidans BOA4 and/or irrigation with an extract of the marine algae Enteromorpha intestinalis (EI) is herein evaluated. The plant shoots and roots were harvested separately on day 50, following extensive saline stress. The addition of BOA4 and/or EI extract resulted in an average increase of 33% in plant shoot DW, but an averaged decrease of 44% in the root to shoot biomass ratio. Anthocyanin content increased by over 34% and 44% with EI and BOA4 plus EI treatments, respectively. Since enhanced protein tyrosine nitration (PTN) is a known plant response to salt stress, the PTN level was inspected through 3-nitrotyrosine content determination. This was drastically increased by salt stress; however, BOA4, EI or both caused an averaged PTN decrease of 30% in stressed roots or shoots. This PTN response could be associated with tomato phenotypic characteristics and is postulated to be inversely correlated to cytokinin contents in stressed plants, namely cis-zeatin-type-cis-zeatin (cZ) plus cis-zeatin riboside (cZR), and isopentenyladenine (iP). The latter showed a drastic average increase by 3.6-fold following BOA4 and/or EI treatments of salinized tomato. This increment could be related to cytokinin biosynthesis induced by the applied bio-stimulants; IP and derivatives are the main cytokinins in seaweeds, and Achromobacter xylosoxidans BOA4 was shown to produce up to 17.5 pmol mL−1 of isopentenyladenine. This work is the first report on the influence of bio-stimulants, used to improve salt stress tolerance, on plant PTN levels; BOA4 and/or EI treatments decreased PTN, while increasing cis-zeatin-type and iP cytokinins in tomato, the latter showed an enhanced tolerance to salt stress. [ABSTRACT FROM AUTHOR]

Plant NAC transcription factors play vital roles in diverse biological processes, especially in response to stress. However, only a limited number of the FtNAC genes have been cloned and functionally analyzed in Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn.), which is a coarse grain crop that is highly resistant to abiotic stress. Here, we identified seven Tartary buckwheat FtNAC genes, namely FtNAC11, FtNAC12, FtNAC26, FtNAC28, FtNAC65, FtNAC70, and FtNAC78. Multiple-sequence alignments revealed that all of them contained the conserved NAM domain, which consisted of the A, B, C, D, and E subdomains. Seven NAC proteins were classified into six subgroups based on phylogenetic analyses. Cis-acting regulatory elements analyses (CARE) indicated that there were numerous CAREs related to biotic and abiotic responses and hormone responses in the promoters of FtNAC genes. qRT-PCR showed that they were tissue-specifically expressed and could be induced by four out of six treatments, namely PEG, NaCl, cold, MeJA, ABA, and GA, implying that they were abiotic and hormone responsive. Among these, FtNAC70 was the most strongly induced gene and could be induced by all six treatments. Meanwhile, FtNAC70-overexpressed Arabidopsis showed more resistance to salt and drought. The identification, phylogenetics, expression, and functional study of seven stress-responsive FtNAC genes laid a foundation for further research on the molecular mechanism of abiotic stress regulated by NAC TFs in Tartary buckwheat. [ABSTRACT FROM AUTHOR]

Aquaporins are a specific type of membrane channel proteins that efficiently transport water molecules and other small molecular substrates in plants. In this study, we isolated the plasma membrane aquaporin gene EuPIP1;2 from Eucommia ulmoides, an important medicinal plant in China. The EuPIP1;2 protein was localized on the plasma membrane. Quantitative RT-PCR analysis revealed that EuPIP1;2 was constitutively expressed in all analyzed tissues, with the highest expression levels detected in the fruit and root. Overexpression of EuPIP1;2 in transgenic tobacco enhanced plant tolerance of drought and salinity. Under drought and salt stress, the transgenic lines exhibited higher percentage germination, longer roots, and enhanced percentage survival compared with wild-type plants. The contents of malonaldehyde and proline suggested that EuPIP1;2 improved drought and salt tolerance in transgenic lines by reducing damage to membranes and improving osmotic adjustment. We predict that EuPIP1;2 could be applied to improve drought and salt tolerance in transgenic plants. [ABSTRACT FROM AUTHOR]

Abiotic stresses are the biggest threat to the increasing population worldwide. Salt stress is one of the most significant abiotic stresses, affecting 20% of the crop production around the world. Plant-derived smoke (PDS) has been reported as a biologically active plant product in stimulating seed germination, seedling growth and physiological characteristics of crops under abiotic stress conditions. Nevertheless, studies showing how PDS alleviates salt stress are largely unknown. Here, we report the molecular mechanism of how PDS could alleviate salt stress in wheat. Initially, PDS at 2000 ppm enhanced seed germination, root/shoot length and seedling fresh weight. However, PDS at 1000 and 500 ppm did not show any significant effect. Salt stress at 150 and 200 mM significantly reduced seed germination rate, root/shoot length and fresh weight of the wheat seedlings. Interestingly, PDS supplementation at 2000 ppm concentration was sufficient to restore seed germination under salt stress condition. Moreover, PDS improved root/shoot length and seedling biomass under 150 and 200 mM salt stress, suggesting that PDS is a potent plant product, capable of abiotic stress alleviation in crops. In comparison to the control, PDS-treated seedlings displayed increased activity of major antioxidative enzymes such as superoxide dismutase, peroxidase and ascorbate peroxidase under salt stress, resulting in reduced levels of hydrogen peroxide and lipid peroxidase, showing that PDS can possibly help in salt stress amelioration by regulating redox homeostasis. Importantly, salt stress altered the expression of germination marker genes, such as TaSAM, TaPHY, TaBGU (germination positive effectors), TaLEA and TaGARS34 (germination negative effectors), suggesting the potential role of PDS in the germination pathway under salt stress. Further, PDS modulated the transcript levels of several salt stress stress-responsive genes, including TaSOS4, TaBADH and TaHKT2. In conclusion, this study provides a molecular and physiological basis for elucidating the mechanism of how PDS functions in stress induction in wheat, as well as demonstrates the importance of PDS in agricultural practices, laying the groundwork for future research into the role of PDS in the amelioration of abiotic stresses in various plants. [ABSTRACT FROM AUTHOR]

Salt stress is one of the abiotic factors that causes adverse effects in plants and there is an urgent need to detect salt stress in plants as early as possible. Multicolor fluorescence imaging, as a powerful tool in plant phenotyping, can provide information about primary and secondary metabolism in plants to detect the responses of the plants exposed to stress in the early stage. The purpose of this study was to evaluate the potential of multicolor fluorescence imaging's application in the early detection of salt stress in plants. In this study, the measurements were conducted on Arabidopsis and the multicolor fluorescence images were acquired at 440, 520, 690, and 740 nm with a self-developed imaging system consisting of a UV light-emitting diode (LED) panel for an excitation at 365 nm, a charge coupled device (CCD) camera, interference filters, and a computer. We developed a classification method using the imaging analysis of multicolor fluorescence based on principal component analysis (PCA) and a support vector machine (SVM). The results showed that the four principal fluorescence feature combinations were the ideal indicators as the inputs of the SVM model, and the classification accuracies of the control and salt-stress treatment at 5 days and 9 days were 92.65% and 98.53%, respectively. The results indicated that multicolor fluorescence imaging combined with PCA and SVM could act as a tool for early detection in salt-stressed plants. [ABSTRACT FROM AUTHOR]

For the dissection and identification of the molecular response mechanisms to salt stress in cannabis, an experiment was conducted surveying the diversity of physiological characteristics. RNA-seq profiling was carried out to identify differential expression genes and pathway which respond to salt stress in different cannabis materials. The result of physiological diversity analyses showed that it is more sensitive to proline contents in K94 than in W20; 6 h was needed to reach the maximum in K94, compared to 12 h in W20. For profiling 0–72 h after treatment, a total of 10,149 differentially expressed genes were identified, and 249 genes exhibited significantly diverse expression levels in K94, which were clustered in plant hormone signal transduction and the MAPK signaling pathway. A total of 371 genes showed significant diversity expression variations in W20, which were clustered in the phenylpropanoid biosynthesis and plant hormone signal transduction pathway. The pathway enrichment by genes which were identified in K94 and W20 showed a similar trend to those clustered in plant hormone signal transduction pathways and MAPK signaling. Otherwise, there were 85 genes which identified overlaps between the two materials, indicating that these may be underlying genes related to salt stress in cannabis. The 86.67% agreement of the RNA-seq and qRT-PCR indicated the accuracy and reliability of the RNA-seq technique. Additionally, the result of physiological diversity was consistent with the predicted RNA-seq-based findings. This research may offer new insights into the molecular networks mediating cannabis to respond to salt stress. [ABSTRACT FROM AUTHOR]

Heavy metal pollution of soil restricts the sustainable use of land and poses risks to human health throughout the world. Changes in the physicochemical properties of soil may increase the mobility of heavy metals in the soil ecosystem and lead to groundwater pollution. In this study, the effects of different salt solutions (NaCl, CaCl2, NaNO3, MgCl2, Na2SO4, and mixed salts) on the release of Cd from soil were investigated by batch desorption tests and the Freundlich isothermal sorption model. Increased concentrations of the salts, except for NaNO3, significantly promoted Cd release (R2 > 0.9, p < 0.01). Under the salt stress, Cd release from the test soils was promoted more by CaCl2 and MgCl2 than by the other salts, and the average desorption rates of eight soil samples at 3.5% salt concentration were 11.15% and 10.80%, respectively, which were much higher than those of NaCl (4.05%), Na2SO4 (0.41%), and NaNO3 (0.33%). Ca2+ and Mg2+ showed better ion exchange capacity than Na+ to promote Cd release; for anions, Cl− formed hydrophilic Cd chloride complexes with Cd in soil. In addition, principal component analysis results revealed that Cd release was mainly influenced by soil texture, cation exchange capacity, and iron–manganese oxide content of the soil. The Cd release level for different soil samples was most closely related to the proportion of fine particles in the soil. The higher the clay content was, the higher the Cd desorption rate. [ABSTRACT FROM AUTHOR]

Salinity is considered among the abiotic stresses most impacting agriculture for its ability to interfere with crop development and quality. For this reason, practices and innovations that could contain the deleterious effects of such stress are of pivotal importance for maintaining acceptable crop yields. In this context, this work has concerned the study of severe salt stress (100 mM NaCl) on maize seedlings and the effects of a plant biostimulant (Megafol–Meg) in helping plants to cope with this adversity. Biomass production, pigments, the content Na+ and K+, the accumulation of hydrogen peroxide (H2O2) and lipid peroxidation products (MDA), total phenolic compounds (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) were investigated in control samples, in samples treated with NaCl alone, and in samples treated with NaCl in combination with the biostimulant. The results showed that the biostimulant significantly mitigated the impact of the salt stress on shoot length and fresh weight, on chlorophyll and carotenoid contents, and reduced the amount of Na+ taken up by the species. Regarding the oxidative status, the biostimulated samples revealed lower amounts of H2O2 and MDA, while maize seedlings grown with NaCl alone exhibited the highest increases in the TPC, ABTS, and FRAP. The explanation for these effects is provided by highlighting the effectiveness of the biostimulant in avoiding Na+ accumulation, which resulted in a lower content of H2O2, MDA, TPC, and antioxidant activity. [ABSTRACT FROM AUTHOR]