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Background: The growth arrest and DNA damage-inducible 45 (Gadd45) gene has been implicated in various central nervous system (CNS) functions, both normal and pathological, including aging, memory, and neurodegenerative diseases. In this study, we examined whether Gadd45A deletion triggers pathways associated with neurodegenerative diseases including Alzheimer's disease (AD)., Methods: Utilizing transcriptome data from AD-associated hippocampus samples, we identified Gadd45A as a pivotal regulator of autophagy. Comprehensive analyses, including Gene Ontology enrichment and protein-protein interaction network assessments, highlighted Cdkn1A as a significant downstream target of Gadd45A. Experimental validation confirmed Gadd45A's role in modulating Cdkn1A expression and autophagy levels in hippocampal cells. We also examined the effects of autophagy on hippocampal functions and proinflammatory cytokine secretion. Additionally, a murine model was employed to validate the importance of Gadd45A in neuroinflammation and AD pathology., Results: Our study identified 20 autophagy regulatory factors associated with AD, with Gadd45A emerging as a critical regulator. Experimental findings demonstrated that Gadd45A influences hippocampal cell fate by reducing Cdkn1A expression and suppressing autophagic activity. Comparisons between wild-type (WT) and Gadd45A knockout (Gadd45A -/- ) mice revealed that Gadd45A -/- mice exhibited significant cognitive impairments, including deficits in working and spatial memory, increased Tau hyperphosphorylation, and elevated levels of kinases involved in Tau phosphorylation in the hippocampus. Additionally, Gadd45A -/- mice showed significant increases in pro-inflammatory cytokines and decreases autophagy markers in the brain. Neurotrophin levels and dendritic spine length were also reduced in Gadd45A -/- mice, likely contributing to the observed cognitive deficits., Conclusions: These findings support the direct involvement of the Gadd45A gene in AD pathogenesis, and enhancing the expression of Gadd45A may represent a promising therapeutic strategy for the treatment of AD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Rotavirus, a dsRNA virus in the Reoviridae family, shows a segmented genome. The VP1 gene encodes the RNA-dependent RNA polymerase (RdRp). This study aims to develop a multiepitope-based vaccine targeting RdRp using immunoinformatic approaches. In this study, 100 available nucleotide sequences of VP1-Rotavirus belonging to different strains across the world were retrieved from NCBI database. The selected sequences were aligned, and a global consensus sequence was developed by using CLC work bench. The study involved immunoinformatic approaches and molecular docking studies to reveal the promiscuous epitopes that can be eventually used as active vaccine candidates for Rotavirus. In total, 27 highly immunogenic, antigenic, and non-allergenic T-cell and B-cell epitopes were predicted for the Multiepitope vaccine (MEV) against rotavirus. It was also observed that MEV can prove to be effective worldwide due to its high population coverage, demonstrating the consistency of this vaccine. Moreover, there is a high docking interaction and immunological response with a binding score of -50.2 kcal/mol, suggesting the vaccine's efficacy. Toll-like receptors (TLRs) also suggest that the vaccine is physiologically and immunologically effective. Collectively, our data point to an effective MEV against rotavirus that can effectively reduce viral infections and improve the health status worldwide.

Climate change-induced drought stress decreases crop productivity, but the application of β-sitosterol (BS) and biochar (BC) boosts crop growth and yield. A pot experiment was conducted to examine the effects of the alone and combined application of BS and BC on the growth and yield of Phaseolus vulgaris under drought stress. The synergistic application of BS and BC increased plant height (46.9cm), shoot dry weight (6.9g/pot), and root dry weight (2.5g/pot) of P. vulgaris plants under drought stress. The trend of applied treatments for photosynthetic rate remained as BC (15%)

Introduction: Recent advancements in nanotechnology present promising opportunities for enhancing crop resilience in adverse environmental conditions., Methods: In this study, we conducted a factorial experiment to investigate the influence of potassium nanosilicate (PNS) on sorghum plants exposed to varying degrees of drought stress A randomized complete block design with three replications was employed to subject the sorghum plants to different drought conditions. The three levels of stress were designated as non-stress (NS at -0.03 MPa), moderate stress (MD at -0.6 MPa), and severe stress (SD at -1.2 MPa). The plants were administered PNS at concentrations of 0 mM (control), 3.6 mM Si, and 7.2 mM Si., Results and Discussion: As drought stress intensified, we observed significant reductions in multiple plant parameters, including height, fresh weight, dry weight, leaf number, stem diameter, cluster length, seed weight, and nutrient uptake, with the most pronounced effects observed under SD conditions. Interestingly, nitrogen (N) and potassium (K) levels exhibited an increase under drought stress and PNS application, peaking at MD, alongside Si concentrations. Notably, PNS application facilitated enhanced nutrient uptake, particularly evident in the significant increase in nitrogen concentration observed at 3.6 mM PNS. Furthermore, the application of PNS significantly enhanced the fresh weight and nutrient concentrations (notably K and Si) in sorghum seeds under drought stress, despite varying statistical significance for other nutrients. These findings shed light on the mechanisms through which PNS exerts beneficial effects on plant performance under drought stress. By elucidating the complex interactions between PNS application, drought stress, and plant physiology, this study contributes significantly to the development of sustainable agricultural practices aimed at bolstering crop resilience and productivity in water-limited environments., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Alharbi, Alnusairi, Alnusaire, Alghanem, Alsudays, Alaklabi and Soliman.)

Background: Taurine, an amino acid abundantly found in the brain and other tissues, has potential neuroprotective properties. Alzheimer's disease (AD) is a commonly occurring type of dementia, which becomes more prevalent as people age. This experiment aimed to assess the neuroprotective effects of taurine on SH-SY5Y cells by examining its impact on Dihydrotestosterone (DHT), Dihydroprogesterone (DHP), as well as the expression of miRNA-21 and miRNA-181., Methods: The effects of various taurine concentrations (0.25, and 0.75 mg/mL), and LPS (0.1, and 12 mg/mL) on the SH-SY5Y cell line were assessed using the MTT assay. The levels of DHT and DHP were quantified using an ELISA kit. Additionally, the expression levels of miRNA-181 and miRNA-21 genes were examined through Real-Time PCR analysis., Results: The results of the MTT assay showed that treatment with taurine at concentrations of 0.25, and 0.75 mg/mL reduces the toxicity of LPS in SH-SY5Y cells. ELISA results indicated that taurine at a concentration of 0.25, and 0.75 mg/mL significantly elevated DHT and DHP hormones in the SH-SY5Y cell line compared to the untreated group ( p  < 0.01). The expression levels of IL-1β and IL-6 were decreased under the influence of LPS in SH-SY5Y cells after taurine treatment (p < 0.01). Gene expression analysis revealed that increasing taurine concentration resulted in heightened expression of miRNA-181 and miRNA-21, with the most significant increase observed at a concentration of 0.75 mg/mL ( p  < 0.001)., Conclusion: Our study findings revealed that the expression of miRNA-181 and miRNA-21 can be enhanced by taurine. Consequently, exploring the targeting of taurine, miRNA-181, and miRNA-21 or considering hormone therapy may offer potential therapeutic approaches for treating AD or alleviating severe symptoms. Nonetheless, in order to fully comprehend the precise mechanisms involved, additional research is required., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Almohaimeed, Almars, Alsulaimani, Basri, Althobaiti, Albalaw, Alsharif, Al Abdulmonem, Hershan and Soliman.)

The coronavirus disease 2019 (COVID-19) was first found in Wuhan, China, in December 2019. Because the virus spreads quickly, it quickly became a global worry. Coronaviridae is the family that contains both SARS-CoV-2 and the viruses that came before (i.e., MERS-CoV and SARS-CoV). Recent sources portray that the COVID-19 virus has affected 344,710,576 people worldwide and killed about 5,598,511 people in the last 2 years. The B.1.1.529 strain, later called "Omicron," was named a Variant of Concern on November 24, 2021. The SARS-CoV-2 virus has gone through a never-ending chain of changes that have never happened before. As a result, it has many different traits. Most of these changes have occurred in the spike protein, where antibodies bind. Because of these changes, the Omicron type is very contagious and easy to pass on. There have been a lot of studies done to try to figure out this new challenge in the COVID-19 strains race, but there is still a lot that needs to be explained. This study focuses on virtual screening, docking, and molecular dynamic analysis; we aimed to identify therapeutic candidates for the SARS-CoV-2 variant Omicron based on their ability to inhibit non-structural proteins. We investigate the prediction of the properties of a substantial database of drug molecules obtained from the OliveNet™ database. Compounds that did not exhibit adequate gastrointestinal absorption and failed the Lipinski test are not considered for further research. The filtered compounds were coupled with our primary target, SARS-CoV-2 Omicron spike protein. We focused on SARS-CoV-2 Omicron spike protein and filtering potent olive compounds. Pinoresinol, the most likely candidate, is bound best (- 8.5 kcal/mol). Pinoresinol's strong interaction with the active site made the complex's dynamic structure more resilient. MD simulations explain the protein-ligand complex's stability and function. Pinoresinol may be a promising SARS-CoV-2 Omicron spike protein receptor lead drug, and additional research may assist the scientific community., (© 2023. The Author(s), under exclusive licence to Institute of Plant Genetics Polish Academy of Sciences.)

Chromium (Cr) toxicity can negatively affect plant growth and development, impacting agricultural productivity and posing risks to human health. Metallic nanoparticles (MNPs) such as titanium dioxide (TiO 2 ) and natural growth regulators such as melatonin (MT) become a promising technology to manage heavy metal-contaminated soils and promote safe food production. The present work was conducted to find the effect of foliar application of TiO 2 NPs (15 mg L -1 ) and MT (100 µM) on growth, biochemical attributes, and Cr accumulation in plant tissues of Melissa officinalis L. under Cr toxicity (50 and 100 mg Cr kg -1 soil). The results showed that Cr toxicity led to decreased plant performance, where 100 mg Cr kg -1 soil led to notable decreases in shoot weight (28%), root weight (27%), essential oil (EO) yield (34%), chlorophyll (Chl) a + b (33%), while increased malondialdehyde (MDA, 30%), superoxide dismutase (SOD) activity (51%), and catalase (CAT) activity (122%). The use of TiO 2 NPs and MT, particularly their co-application, remarkably reduced Cr toxicity by enhancing plant weight, Chl content, and lowered MDA and antioxidant activity. Total phenolic content (TPC), total flavonoid content (TFC), EO percentage, and rosmarinic acid in plants treated with Cr at 50 mg Cr kg -1 soil and co-application of TiO 2 NPs and MT were relatively higher than in other treatments. Under 100 mg Cr kg -1 soil, the synergic effect of TiO 2 NPs and MT-enhanced rosmarinic acid content (22%) but lowered Cr accumulation in roots (51%) and shoots (72%). Heat map analysis showed that CAT, SOD, MDA, and EO yield had the maximum variability under Cr, TiO 2 NPs, and MT. Exogenous TiO 2 NPs and MT can be recommended to modulate Cr toxicity in lemon balm under soil Cr toxicity., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Melanoma, a highly invasive type of skin cancer that penetrates the entire dermis layer, is associated with increased mortality rates. Excessive exposure of the skin to sunlight, specifically ultraviolet radiation, is the underlying cause of this malignant condition. The appearance of unique skin moles represents a visible clue, referred to as the "ugly duckling" sign, indicating the presence of melanoma and its association with cellular DNA damage. This research aims to explore potential biomarkers derived from microarray data, employing bioinformatics techniques and methodologies, for a thorough investigation of melanoma skin cancer. The microarray dataset for melanoma skin cancer was obtained from the GEO database, and thorough data analysis and quality control measures were performed to identify differentially expressed genes (DEGs). The top 14 highly expressed DEGs were identified, and their gene information and protein sequences were retrieved from the NCBI gene and protein database. These proteins were further analyzed for domain identification and network analysis. Gene expression analysis was conducted to visualize the upregulated and downregulated genes. Additionally, gene metabolite network analysis was carried out to understand the interactions between highly interconnected genes and regulatory transcripts. Molecular docking was employed to investigate the ligand-binding sites and visualize the three-dimensional structure of proteins. Our research unveiled a collection of genes with varying expression levels, some elevated and others reduced, which could function as promising biomarkers closely linked to the development and advancement of melanoma skin cancer. Through molecular docking analysis of the GINS2 protein, we identified two natural compounds (PubChem-156021169 and PubChem-60700) with potential as inhibitors against melanoma. This research has implications for early detection, treatment, and understanding the molecular basis of melanoma., (© 2023. The Author(s), under exclusive licence to Institute of Plant Genetics Polish Academy of Sciences.)

Neuro-oncological and neurodegenerative disorders, represented paradigmatically by glioblastoma and Alzheimer's disease, respectively, persist as formidable challenges in the biomedical realm. The interconnected molecular underpinnings of these conditions necessitate rigorous and novel therapeutic examinations. This comprehensive research was anchored on the premise of unveiling the therapeutic potential and specificity of Lupenone, a potent phytoconstituent, in targeting the molecular pathways underpinning both glioblastoma and Alzheimer's amyloid beta pathology. This was gauged through its interactions with key protein structures, 5H08 and 2ZHV. An integrative approach was adopted, marrying advanced proteomics and modern computer-aided drug design techniques. Molecular docking of Lupenone with 5H08 and 2ZHV was meticulously executed, with subsequent molecular dynamics simulations providing insights into the stability, viability, and intricacies of these interactions. Lupenone demonstrated profound binding affinities, evidenced by robust docking scores of -9.54 kcal/mol for 5H08 and -10.59 kcal/mol for 2ZHV. These interactions underscored Lupenone's eminent therapeutic potential in mitigating glioblastoma and modulating the amyloid beta pathology inherent to Alzheimer's. The introduction of Proteolysis Targeting Chimeras (PROTACs) further magnified the therapeutic prospects, accentuating Lupenone's efficacy. The findings of this study not only underscore the therapeutic acumen of Lupenone in addressing the challenges posed by glioblastoma and Alzheimer's but also lay a strong foundation for its consideration as a leading candidate in future neuro-oncological and neurodegenerative research endeavors. Given the compelling in-silico data, a clarion call is made for its empirical validation in holistic in-vivo settings, potentially pioneering a new therapeutic epoch in both glioblastoma and Alzheimer's interventions., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Climate change has become the global concern due to its drastic effects on the environment. Agriculture sector is the backbone of food security which remains at the disposal of climate change. Heat stress is the is the most concerning effect of climate change which negatively affect the plant growth and potential yields. The present experiment was conducted to assess the effects of exogenously applied β-sitosterol (Bs at 100 mg/L) and eucalyptus biochar (Eb at 5%) on the antioxidants and nutritional status in Thymus vulgaris under heat stressed conditions. The pot experiment was conducted in completely randomize design in which thymus plants were exposed to heat stress (33 °C) and as a result, plants showed a substantial decline in morpho-physiological and biochemical parameters e.g., a reduction of 59.46, 75.51, 100.00, 34.61, 22.65, and 38.65% was found in plant height, shoot fresh weight, root fresh weight, dry shoot weight, dry root weight and leaf area while in Bs + Eb + heat stress showed 21.16, 56.81, 67.63, 23.09, 12.84, and 35.89% respectively as compared to control. In the same way photosynthetic pigments, transpiration rate, plant nutritional values and water potential increased in plants when treated with Bs and Eb in synergy. Application of Bs and Eb significantly decreased the electrolytic leakage of cells in heat stressed thymus plants. The production of reactive oxygen species was significantly decreased while the synthesis of antioxidants increased with the application of Bs and Eb. Moreover, the application Bs and Eb increased the concentration of minerals nutrients in the plant body under heat stress. Our results suggested that application of Bs along with Eb decreased the effect of heat stress by maintaining nutrient supply and enhanced tolerance by increasing the production of photosynthetic pigments and antioxidant activity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Salinity adversely affects the plant's morphological characteristics, but the utilization of aqueous algal extracts (AE) ameliorates this negative impact. In this study, the application of AE derived from Chlorella vulgaris and Dunaliella salina strains effectively reversed the decline in biomass allocation and water relations, both in normal and salt-stressed conditions. The simultaneous application of both extracts in salt-affected soil notably enhanced key parameters, such as chlorophyll content (15%), carotene content (1%), photosynthesis (25%), stomatal conductance (7%), and transpiration rate (23%), surpassing those observed in the application of both AE in salt-affected as compared to salinity stress control. Moreover, the AE treatments effectively mitigated lipid peroxidation and electrolyte leakage induced by salinity stress. The application of AE led to an increase in GB (6%) and the total concentration of free amino acids (47%) by comparing with salt-affected control. Additionally, salinity stress resulted in an elevation of antioxidant enzyme activities, including superoxide dismutase, ascorbate peroxidase, catalase, and glutathione reductase. Notably, the AE treatments significantly boosted the activity of these antioxidant enzymes under salinity conditions. Furthermore, salinity reduced mineral contents, but the application of AE effectively counteracted this decline, leading to increased mineral levels. In conclusion, the application of aqueous algal extracts, specifically those obtained from Chlorella vulgaris and Dunaliella salina strains, demonstrated significant efficacy in alleviating salinity-induced stress in Phaseolus vulgaris plants.

The present study was conducted to examine the potential role of Plantago ovata Forsk leaf extract (POLE) which was applied at various concentration levels (control, hydropriming, 10, 20, 30, and 40% POLE) to the wheat ( Triticum aestivum L.) seedlings. Drought stressed was applied at 60% osmotic potential (OM) to the T. aestivum seedlings to study various parameters such as growth and biomass, photosynthetic pigments and gas exchange characteristics, oxidative stress and response of various antioxidants and nutritional status of the plants. Various growth parameters such as gaseous exchange attributes, antioxidants and nutritional status of T. aestivum were investigated in this study. It was evident that drought-stressed condition had induced a negative impact on plant growth, photosynthetic pigment, gaseous exchange attributes, stomatal properties, and ion uptake by different organs (roots and shoots) of T. aestivum . The decrease in plant growth resulted from oxidative stress and overcome by the antioxidant (enzymatic and non-enzymatic) compounds, since their concentration increased in response to dehydration. Seed priming with POLE positively increased plant growth and photosynthesis, by decreasing oxidative stress indicators and increasing activities of antioxidant (enzymatic and non-enzymatic) compounds, compared to the plants which were grown without the application of POLE. Our results also depicted that optimum concentration of POLE for T. aestivum seedlings under drought condition was 20%, while further increase in POLE (30 and 40%) induced a non-significant ( P < 0.05) effect on growth (shoot and root length) and biomass (fresh and dry weight) of T. aestivum seedling. Here we concluded that the understanding of the role of seed priming with POLE in the increment of growth profile, photosynthetic measurements and nutritional status introduces new possibilities for their effective use in drought-stressed condition and provides a promising strategy for T. aestivum tolerance against drought-stressed condition., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Alharbi, Alhaithloul, Alayafi, Al-Taisan, Alghanem, Al-Mushhin, Soliman, Alsubeie, Vodnar and Marc.)

The influence of dry leachates of Acasia saligna was tested on the seedling growth, photosynthesis, biochemical attributes, and gene expression of the economically important crops, including wheat ( Triticum aestivum L.), radish ( Raphanus sativus L.), barley ( Hordeum vulgare L.) and arugula ( Eruca sativa L.). Different concentrations (5%, 10%, 15%, 20%, and 25%) of stem extract (SE) and leaf extract (LE) of A. saligna were prepared, and seedlings were allowed to grow in Petri plates for 8 days. The results showed that all plant species exhibited reduced germination rate, plant height, and fresh and dry weight due to leachates extracts of A. saligna . Moreover, the activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX), exhibited differential regulation due to the extract treatment. The SOD was increased with increasing the concentration of extracts, while CAT and APX activities were decreased with increasing the extract concentrations. In addition, leachate extract treatment decrease chlorophyll content, photosynthesis, PSII activity, and water use efficiency, with evident effects at their higher concentrations. Furthermore, the content of proline, sugars, protein, total phenols, and flavonoids were reduced considerably due to leachates extract treatments. Furthermore, seedlings treated with high concentrations of LE increased the expression of genes. The present results lead to the conclusion that A. saligna contains significant allelochemicals that interfere with the growth and development of the tested crop species and reduced the crops biomass and negatively affected other related parameters. However, further studies are suggested to determine the isolation and purification of the active compounds present in A. saligna extracts., Competing Interests: The authors declare that they have no competing interests., (© 2022 ALHaithloul et al.)

Increasing ultraviolet (UV) radiation is causing oxidative stress that accounts for growth and yield losses in the present era of climate change. Plant hormones are useful tools for minimizing UV-induced oxidative stress in plants, but their putative roles in protecting tomato development under UVC remain unknown. Therefore, we investigated the underlying mechanism of pre-and post-kinetin (Kn) treatments on tomato plants under UVC stress. The best dose of Kn was screened in the preliminary experiments, and this dose was tested in further experiments. UVC significantly decreases growth traits, photosynthetic pigments, protein content, and primary metabolites (proteins, carbohydrates, amino acids) but increases oxidative stress biomarkers (lipid peroxidation, lipoxygenase activity, superoxide anion, hydroxyl radical, and hydrogen peroxide) and proline content. Treatment of pre-and post-kinetin spraying to tomato plants decreases UVC-induced oxidative stress by restoring the primary and secondary metabolites' (phenolic compounds, flavonoids, and anthocyanins) status and upregulating the antioxidant defense systems (non-enzymatic antioxidants as ascorbate, reduced glutathione, α-tocopherol as well as enzymatic antioxidants as superoxide dismutase, catalase, ascorbate peroxidase, glutathione peroxidase, glutathione-S-transferase, and phenylalanine ammonia-lyase). Thus, the application of Kn in optimum doses and through different modes can be used to alleviate UVC-induced negative impacts in tomato plants., (© 2022. The Author(s).)

The contamination of heavy metals is a cause of environmental concern across the globe, as their increasing levels can pose a significant risk to our natural ecosystems and public health. The present study was aimed to evaluate the ability of a copper (Cu)-resistant bacterium, characterized as Bacillus altitudinis MT422188, to remove Cu from contaminated industrial wastewater. Optimum growth was observed at 37°C, pH 7, and 1 mm phosphate, respectively. Effective concentration 50 (EC 50 ), minimum inhibitory concentration (MIC), and cross-heavy metal resistance pattern were observed at 5.56 mm, 20 mm, and Ni > Zn > Cr > Pb > Ag > Hg, respectively. Biosorption of Cu by live and dead bacterial cells in its presence and inhibitors 1 and 2 (DNP and DCCD) was suggestive of an ATP-independent efflux system. B. altitudinis MT422188 was also able to remove 73 mg/l and 82 mg/l of Cu at 4th and 8th day intervals from wastewater, respectively. The presence of Cu resulted in increased GR (0.004 ± 0.002 Ug -1 FW), SOD (0.160 ± 0.005 Ug -1 FW), and POX (0.061 ± 0.004 Ug -1 FW) activity. Positive motility (swimming, swarming, twitching) and chemotactic behavior demonstrated Cu as a chemoattractant for the cells. Metallothionein (MT) expression in the presence of Cu was also observed by SDS-PAGE. Adsorption isotherm and pseudo-kinetic-order studies suggested Cu biosorption to follow Freundlich isotherm as well as second-order kinetic model, respectively. Thermodynamic parameters such as Gibbs free energy (∆G°), change in enthalpy (∆H° = 10.431 kJ/mol), and entropy (∆S° = 0.0006 kJ/mol/K) depicted the biosorption process to a feasible, endothermic reaction. Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Energy-Dispersive X-Ray Spectroscopy (EDX) analyses revealed the physiochemical and morphological changes in the bacterial cell after biosorption, indicating interaction of Cu ions with its functional groups. Therefore, these features suggest the potentially effective role of B. altitudinis MT422188 in Cu bioremediation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Khan, Kamran, Kadi, Hassan, Elhakem, Sakit ALHaithloul, Soliman, Zahid Mumtaz, Ashraf and Shamim.)

Excess selenium (Se) causes toxicity, and nitric oxide (NO)'s function in spermine (Spm)-induced tolerance to Se stress is unknown. Using wheat plants exposed to 1 mM sodium selenate-alone or in combination with either 1 mM Spm, 0.1 mM NO donor sodium nitroprusside (SNP) or 0.1 mM NO scavenger cPTIO-the potential beneficial effects of these compounds to palliate Se-induced stress were evaluated at physiological, biochemical and molecular levels. Se-treated plants accumulated Se in their roots (92%) and leaves (95%) more than control plants. Furthermore, Se diminished plant growth, photosynthetic traits and the relative water content and increased the levels of malondialdehyde, H 2 O 2 , osmolyte and endogenous NO. Exogenous Spm significantly decreased the levels of malondialdehyde by 28%, H 2 O 2 by 37% and electrolyte leakage by 42%. Combined Spm/NO treatment reduced the Se content and triggered plant growth, photosynthetic traits, antioxidant enzymes and glyoxalase systems. Spm/NO also upregulated MTP1 , MTPC3 and HSP70 and downregulated TaPCS1 and NRAMP1 (metal stress-related genes involved in selenium uptake, translocation and detoxification). However, the positive effects of Spm on Se-stressed plants were eliminated by the NO scavenger. Accordingly, data support the notion that Spm palliates selenium-induced oxidative stress since the induced NO elicits antioxidant defence upregulation but downregulates Se uptake and translocation. These findings pave the way for potential biotechnological approaches to supporting sustainable wheat crop production in selenium-contaminated areas.

Myo-inositol has gained a central position in plants due to its vital role in physiology and biochemistry. This experimental work assessed the effects of salinity stress and foliar application of myo-inositol (MYO) on growth, chlorophyll content, photosynthesis, antioxidant system, osmolyte accumulation, and gene expression in quinoa ( Chenopodium quinoa L. var. Giza1). Our results show that salinity stress significantly decreased growth parameters such as plant height, fresh and dry weights of shoot and root, leaf area, number of leaves, chlorophyll content, net photosynthesis, stomatal conductance, transpiration, and Fv/Fm, with a more pronounced effect at higher NaCl concentrations. However, the exogenous application of MYO increased the growth and photosynthesis traits and alleviated the stress to a considerable extent. Salinity also significantly reduced the water potential and water use efficiency in plants under saline regime; however, exogenous application of myo-inositol coped with this issue. MYO significantly reduced the accumulation of hydrogen peroxide, superoxide, reduced lipid peroxidation, and electrolyte leakage concomitant with an increase in the membrane stability index. Exogenous application of MYO up-regulated the antioxidant enzymes' activities and the contents of ascorbate and glutathione, contributing to membrane stability and reduced oxidative damage. The damaging effects of salinity stress on quinoa were further mitigated by increased accumulation of osmolytes such as proline, glycine betaine, free amino acids, and soluble sugars in MYO-treated seedlings. The expression pattern of OSM34, NHX1, SOS1A, SOS1B, BADH, TIP2, NSY, and SDR genes increased significantly due to the application of MYO under both stressed and non-stressed conditions. Our results support the conclusion that exogenous MYO alleviates salt stress by involving antioxidants, enhancing plant growth attributes and membrane stability, and reducing oxidative damage to plants.

Pathogenic infestations are significant threats to vegetable yield, and have become an urgent problem to be solved. Rhizoctonia solani is one of the worst fungi affecting tomato crops, reducing yield in some regions. It is a known fact that plants have their own defense against such infestations; however, it is unclear whether any exogenous material can help plants against infestation. Therefore, we performed greenhouse experiments to evaluate the impacts of R. solani on 15- and 30-day old tomato plants after fungal infestation, and estimated the antifungal activity of nanoparticles (NPs) against the pathogen. We observed severe pathogenic impacts on the above-ground tissues of tomato plants which would affect plant physiology and crop production. Pathogenic infection reduced total chlorophyll and anthocyanin contents, which subsequently disturbed plant physiology. Further, total phenolic contents (TPC), total flavonoid contents (TFC), and malondialdehyde (MDA) contents were significantly increased in pathogen treatments. Constitutively, enhanced activities were estimated for catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX) in response to reactive oxygen species (ROS)in pathogen-treated plants. Moreover, pathogenesis-related genes, namely, chitinase, plant glutathione S-transferase ( GST ), phenylalanine ammonia-lyase ( PAL1 ), pathogenesis-related protein ( PR12 ), and pathogenesis-related protein ( PR1 ) were evaluated, with significant differences between treated and control plants. In vitro and greenhouse antifungal activity of silver nanoparticles (Ag NPs), chitosan nanoparticles, and Ag NPs/CHI NPs composites and plant health was studied using transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectrophotometry. We found astonishing results, namely, that Ag and CHI have antifungal activities against R. solani . Overall, plant health was much improved following treatment with Ag NPs/CHI NPs composites. In order to manage R. solani pathogenicity and improve tomato health, Ag/CHI NPs composites could be used infield as well as on commercial levels based on recommendations. However, there is an urgent need to first evaluate whether these NP composites have any secondary impacts on human health or the environment.

Salinity stress is one of the major environmental constraints responsible for a reduction in agricultural productivity. This study investigated the effect of exogenously applied nitric oxide (NO) (50 μM and 100 μM) in protecting wheat plants from NaCl-induced oxidative damage by modulating protective mechanisms, including osmolyte accumulation and the antioxidant system. Exogenously sourced NO proved effective in ameliorating the deleterious effects of salinity on the growth parameters studied. NO was beneficial in improving the photosynthetic efficiency, stomatal conductance, and chlorophyll content in normal and NaCl-treated wheat plants. Moreover, NO-treated plants maintained a greater accumulation of proline and soluble sugars, leading to higher relative water content maintenance. Exogenous-sourced NO at both concentrations up-regulated the antioxidant system for averting the NaCl-mediated oxidative damage on membranes. The activity of antioxidant enzymes increased the protection of membrane structural and functional integrity and photosynthetic efficiency. NO application imparted a marked effect on uptake of key mineral elements such as nitrogen (N), potassium (K), and calcium (Ca) with a concomitant reduction in the deleterious ions such as Na + . Greater K and reduced Na uptake in NO-treated plants lead to a considerable decline in the Na/K ratio. Enhancing of salt tolerance by NO was concomitant with an obvious down-regulation in the relative expression of SOS1, NHX1, AQP, and OSM-34, while D2-protein was up-regulated.

Drought and heat stress are two dominant abiotic stress factors that often occur simultaneously in nature causing oxidative damage in plants and thus decline in yield. The present study was conducted to examine the γ-aminobutyric acid (GABA)-induced heat and drought tolerance in sunflower through physiological, biochemical and molecular analysis. The results showed that drought and heat stress triggered oxidative stress as revealed by enhanced level in hydrogen peroxide, malondialdehyde and electrolyte leakage. Moreover, the photosynthetic attributes such as photosynthetic rate, stomatal conductance and quantum efficiency declined when subjected to drought and heat stress. In this study, GABA treatment effectively alleviated the drought and heat-induced stress as reflected by significantly higher levels of proline, soluble sugar and total protein content. Besides, the data also revealed the direct relationship between antioxidant enzyme activities (superoxide dismutase, peroxidase, glutathione reductase, monodehydroascorbate peroxidase, ascorbate peroxidase) and the relative expression of genes (Heat Shock Proteins, Dehydrin, Osmotin, Aquaporin, Leaf Embryogenesis Protein), under drought and heat stress. Moreover, a significant increase in gene expression was observed upon GABA treatment with respect to control. This data suggest that GABA-induced drought and heat tolerance in sunflower could involve the improvement in osmolyte metabolism, gene expression and antioxidant enzyme activities and thus a rise in the GABA shunt which in turn provides intermediates during long-term drought and heat stress, thus maintaining homeostasis., (© 2020 Scandinavian Plant Physiology Society.)

In the present study, ameliorative capabilities of wuxal amino (bio stimulant) under salt stress has been investigated through adaptive mechanisms and antioxidant potential in tomato plants. In the experiment, two different concentrations (2 cm L -1 and 3 cm L -1 ) of wuxal amino through foliar application and soil irrigation were applied to the salt (150 mM) treated tomato plants and then morphological traits, photosynthetic pigments, osmolytes, secondary metabolites, oxidative stress and antioxidant enzymes activity were assessed at 60 days after planting. The results revealed that salt stress decreased the growth parameters, photosynthetic pigments, soluble sugars and soluble protein whereas, content of proline, ascorbic acid, total phenols, malondialdehyde, hydrogen peroxide and the activity of antioxidant enzymes activity increased under salt stress. Moreover, Wuxal amino application through foliar or soil to salt stressed plants improved morphological traits, photosynthetic pigments, osmolytes, total phenol and antioxidant enzymes activity. Interestingly, the deleterious impact of salinity on tomato plants were significantly reduced and it can be evident from reduced MDA and H 2 O 2 levels. These responses varied with the mode (foliar or soil) of application of Wuxal amino under different concentrations (2 cm L -1 and 3 cm L -1 ). It was concluded that application of Wuxal amino (2 cm L -1 , foliar) and (3 cm L -1 ; soil) proved best and could be commercially used as eco-friendly tool for the protection of tomato plants grown under salinity stress., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)

Climate change is occurring and is influencing biological systems through augmented temperatures, more inconstant precipitation, and rising CO 2 in the atmosphere. For sustainable landscaping, it was essential to assess the diversity of native/wild grasses and their suitability for turf and to combat the salinity problem in the region. For this purpose, a native halophytic grass, Aeluropus lagopoides, was investigated by conducting mowing tests on its ecotypes during the year 2014-2016 under desert climatic conditions. The research was carried out in two phases, i.e. Phase-I was for collection and establishment of ecotypes from various parts of UAE, while in Phase-II, mowing tests were conducted. During mowing tests, 50 ecotypes of A. lagopoides were given various mowing treatments (i.e. they were cut back at 1-, 2-, 3-, 4- and 5-cm heights) in field conditions. Significant differences were found among various ecotypes for different agronomic parameters such as ground cover, canopy stiffness, leaf number, clippings fresh and dry weights and internode length. Overall, the grass exhibited better performance at mowing heights of 3 and 4 cm, which are the standard mowing heights for turfgrasses. Ecotypes FA5, RA3, RUDA2, RUDA7 and RUADA1 of A. lagopoides showed the best performance against mowing shock and became the candidates for the turfgrass varieties from the native Arabian flora.

Lactic acid bacteria (LAB) can synthesize antimicrobial compounds (AMCs) with nutritional and bioprotective properties in crops and food products. In the current study, AMCs of Lactobacillus coryniformis BCH-4 were evaluated to control fungal spoilage in maize grains. On maize grains treated with 75%-100% ( v / v ) concentrated AMCs, no fungal growth was observed even after 72 h of Aspergillus flavus inoculation. Proximate analysis of treatments A1 (raw grains), A2 ( A. flavus inoculated grains) and A3 ( A. flavus + AMCs inoculated grains) revealed that moisture was significantly ( p ≤ 0.05) high in A2 than A3 and A1. Meanwhile, protein, fat, fiber and ash contents were significantly decreased in A2 compared to A1 and A3. Moreover, β-carotene contents were not statistically different between A1 and A3, while in A2 it was significantly decreased. HPLC analysis revealed the presence of 2-oxopropanoic acid, 2-hydroxypropane-1,2,3-tricarboxylic acid, 2-hydroxybutanedioic acid, 2-hydroxypropanoic acid, propanedioic acid and butanedioic acid, which also showed antifungal activity against Aspergillus flavus . FTIR spectroscopy revealed the presence of hydroxyl, carbonyl and ester-groups along with organic and fatty acids, thereby indicating their participation in inhibitory action. Furthermore, the AMCs were found to be a good alternative to chemical preservatives, thereby not only preserving the nutritive qualities but increasing the shelf life as well.

Chromium (Cr) is among the most widespread toxic trace elements found in agricultural soils resulting from various anthropogenic activities. However, the role of micronutrient-amino acid chelates in reducing Cr toxicity in crop plants has recently been suggested. The present study was conducted to explore the effect of iron (Fe) chelated with lysine (lys) on plant growth, biomass, gaseous exchange attributes, oxidative stress indicators, antioxidant response, and Cr uptake in rapeseed (Brassica napus L.) plants irrigated with different levels of tannery wastewater in soil collected from District Kasur of Pakistan. B. napus seedlings (thirty-day-old) were shifted to pots irrigated with different levels of tannery wastewater. After two weeks, foliar application of Fe-lys (5 mM) was carried out for four successive weeks, and plants were harvested carefully post ten weeks of cultivation in tannery wastewater, under controlled conditions. Toxic levels of Cr in the soil significantly decreased plant height, fresh biomass of roots and leaves, dry biomass of roots and leaves, root length, number of leaves, leaf area, total chlorophyll contents, carotenoid contents, transpiration rate (E), stomatal conductance (g s ), net photosynthesis (P N ), and water use efficiency (WUE). Toxic Cr levels in the soil also increased oxidative stress in the roots and leaves of B. napus plants, which were overcome by the activities of various antioxidant enzymes, such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX). Moreover, increasing levels of Cr in the soil caused a significant increase in the Cr content of the roots and shoots of B. napus plants. The negative effects of Cr toxicity could be overturned by Fe-lys application, significantly increasing plant growth, biomass, chlorophyll content, and gaseous exchange attributes by reducing oxidative stress (H 2 O 2 , MDA, EL) and enhancing antioxidant enzyme activities. Furthermore, foliar application of Fe-lys reduced the Cr concentration and increased essential micronutrients (Fe contents) in the roots and shoots of B. napus plants. These results shed light on the effectiveness of Fe-lys in improving the growth and up-regulation of antioxidant enzyme activities of B. napus in response to Cr stress. However, further studies at field levels are required to explore the mechanisms of Fe-lys-mediated reduction of the toxicity of not only Cr, but possibly also other heavy metals in plants., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Soil in mining areas is typically highly contaminated with heavy metals and lack essential nutrients for plants. Phosphorus reduces oxidative stress, improves plant growth, composition, and cellular structure, as well as facilitates the phytoremediation potential of fibrous crop plant species. In this study, we investigated two jute (Corchorus capsularis) varieties HongTieGuXuan and GuBaChangJia cultivated in copper (Cu)-contaminated soil (2221 mg kg -1 ), under different applications of phosphorus (0, 30, 60, and 120 kg ha -1 ) at both anatomical and physiological levels. At the same Cu concentration, the tolerance index of HongTieGuXuan was higher than that of GuBaChangJia, indicating that HongTieGuXuan may be more tolerant to Cu stress. Although the normal concentration of P (60 kg ha -1 ) in the soil improved plant growth, biomass, chlorophyll content, fibre yield and quality, and gaseous exchange attributes. However, high concentration of P (120 kg ha -1 ) was toxic to both jute varieties affected morphological and physiological attributes of the plants under same level of Cu. Moreover, Cu toxicity increased the oxidative stress in the leaves of both jute varieties was overcome by the activities of antioxidant enzymes. Furthermore, the high concentration of Cu altered the ultrastructure of chloroplasts, plastoglobuli, mitochondria, and many other cellular organelles in both jute varieties. Thus, phytoextraction of Cu by both jute varieties increased with the increase in P application in the Cu-contaminated soil. This suggests that P application enhanced the phytoremediation potential jute plants and can be cultivated as fibrous crop in Cu-contaminated sites., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interests., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The adverse industrial activities discharged contaminated wastewater directly into the water bodies that contain toxic substances such as heavy metals. The contours use of marble industrial effluents may affect the fertility of soil and crop growth. The present study was conducted to investigate the toxic effects of marble industrial effluents (M.E) on Zea mays L under the exogenous application of citric acid (CA) with different combinations such as marble industrial effluent (0, 30%, 60%, 100%) diluted with distilled water and CA (10 mM). The results showed significant decrease in the growth of Zea mays with increasing concentration of marble industrial effluent. The maximum reduction in plant height, root length, number of leaves, leaf area and fresh and dry biomass was observed at the application of 100% M.E as compared to control. Similar to growth conditions the photosynthetic machinery and the activities of antioxidant enzymes (Superoxide dismutase (SOD), Peroxidases (POD), Catalases (CAT), Ascorbate peroxidase (APX)) was also decreased with increasing concentration of M.E. The application of CA significantly alleviated the M.E induced toxic effect on Zea mays and ameliorated the growth, biomass, photosynthesis and antioxidant enzymes activities by reducing the production of reactive oxygen species. The C.A application also enhanced the heavy metal content such as chromium (Cr), cadmium (Cd), Zinc (Zn) in different parts of Zea mays. The results concluded that the Zea mays tolerant varieties can be a potential candidate for the M.E irrigated soil and might be suitable for the phyto-extraction of Cr, Cd and Zn., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Global warming contributes to higher temperatures and reduces rainfall for most areas worldwide. The concurrent incidence of extreme temperature and water shortage lead to temperature stress damage in plants. Seeking to imitate a more natural field situation and to figure out responses of specific stresses with regard to their combination, we investigated physiological, biochemical, and metabolomic variations following drought and heat stress imposition (alone and combined) and recovery, using Mentha piperita and Catharanthus roseus plants. Plants were exposed to drought and/or heat stress (35 °C) for seven and fourteen days. Plant height and weight (both fresh and dry weight) were significantly decreased by stress, and the effects more pronounced with a combined heat and drought treatment. Drought and/or heat stress triggered the accumulation of osmolytes (proline, sugars, glycine betaine, and sugar alcohols including inositol and mannitol), with maximum accumulation in response to the combined stress. Total phenol, flavonoid, and saponin contents decreased in response to drought and/or heat stress at seven and fourteen days; however, levels of other secondary metabolites, including tannins, terpenoids, and alkaloids, increased under stress in both plants, with maximal accumulation under the combined heat/drought stress. Extracts from leaves of both species significantly inhibited the growth of pathogenic fungi and bacteria, as well as two human cancer cell lines. Drought and heat stress significantly reduced the antimicrobial and anticancer activities of plants. The increased accumulation of secondary metabolites observed in response to drought and/or heat stress suggests that imposition of abiotic stress may be a strategy for increasing the content of the therapeutic secondary metabolites associated with these plants.

Water stress reduces crop production significantly, and climate change has further aggravated the problem mainly in arid and semi-arid regions. This was the first study on the possible effects of β-sitosterol application in ameliorating the deleterious changes in wheat induced by water stress under field condition and drip irrigation regimes. A field experiment with the split-plot design was conducted, and wheat plants were foliar sprayed with four β-sitosterol (BBS) concentrations (0, 25, 75, and 100 mg L -1 ) and two irrigation regimes [50 and 100% of crop evapotranspiration (ET c )]. Water stress without BBS treatment reduced biological yield, grain yield, harvest index, and photosynthetic efficiency significantly by 28.9%, 42.8%, 19.6%, and 20.5% compared with the well-watered plants, respectively. Proline content increased in water-stressed and BSS-treated plants, owing to a significant role in cellular osmotic adjustment. Application of BSS was effective in reducing the generation of hydrogen peroxide (H 2 O 2 ) and hence the malondialdehyde content significantly in water-stressed and well-watered wheat plants. Application of BSS up-regulated the activity of antioxidant enzymes (SOD, CAT, POD, and APX) significantly and increased the content of tocopherol, ascorbic acid, and carotene thereby reducing the levels of reactive oxygen species. The increased antioxidant system in BSS treated plants was further supported by the expression level of SOD and dehydrin genes in both water-stressed and well-watered plants. In the present study, the application of BBS at 100 mg L -1 was beneficial and can be recommended for improving the growth and yield of the wheat crop under water stress.

The production and soil accumulation of nanoparticles (NPs) from the industrial sector has increased concerns about their toxic effects in plants which needs the research to explore the ways of reducing NPs toxicity in pants. The gibberellic acid (GA) has been found to reduce abiotic stresses in plants. However, the effect of GA in reducing zinc oxide (ZnO) NPs-mediated toxicity in plants remains unclear. In this study, foliar application of GA was used to explore the possible role in reducing ZnO NPs toxicity in wheat (Triticum aestivum L.) plants. The plants were grown in pots spiked with ZnO NPs (0, 300, 600, 900, 1200 mg/kg) and GA (0, 100, 200 mg/L) was foliar sprayed at different times during the growth period under ambient environmental conditions. Our results demonstrated that GA inhibited the toxicity of ZnO NPs in wheat especially at higher levels of NPs. The GA application improved the plant biomass, photosynthesis, nutrients, and yield under ZnO NPs stress. The GA reduced the Zn accumulation, and reactive oxygen species generation in plants caused by toxicity of NPs. The protective effect of GA in decreasing ZnO NPs-induced oxidative stress was related to GA-mediated enhancement in antioxidant enzymes in plants. The role of GA in enhancing tolerance of wheat against ZnO NPs was further confirmed by the enhancement in nutrient contents in shoots and roots of wheat. Overall, our study provides the evidence that GA can reduce ZnO NPs-induced toxicity in wheat and probably in other crops which needs further in-depth investigation., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Being a primary toxic heavy metal, lead (Pb) contamination presents an imposing environmental and public health concern worldwide. A Bacillus subtilis PbRB3, displaying higher Pb tolerance, was isolated from the textile effluent. The bacterial culture was able to remove >80% of Pb from culture solution. Upon screening in the presence of Pb, PbRB3 strain exhibited significant plant growth promoting potential. A 3 weeks long pot experiment was established to examine the capability of PbRB3 strain for physiological and biochemical traits, and Pb accumulation tendency of mung bean at 250 and 500 mg kg -1 of Pb toxicity, respectively. With respect to control treatments, photosynthetic pigments, protein synthesis, net assimilation rate, transpiration rate and stomatal conductance were significantly constrained by Pb toxicity levels. Intrinsic and instantaneous water use efficiencies were considerably improved in inoculated plants under Pb toxicity. Compared to inoculated control, significantly higher superoxide dismutase activity in both Pb toxicity treatments, while higher malondialdehyde contents only at Pb500 treatment was recorded with PbRB3 inoculation. Catalase activity between Pb250 and Pb500 treatments was comparable at both inoculation level. Moreover, PbRB3 inoculation led to significantly higher peroxidase activity under Pb toxicity treatments compared to inoculated control. The PbRB3 inoculation led to comparable differences in root Pb content between Pb250 and Pb500 treatments. These results suggest that inoculation of Pb tolerant, Bacillus subtilis PbRB3, could be employed to improve mung bean growth potential and adaptation against Pb toxicity, and thereby accelerated Pb rhizoaccumulation from metal contaminated environment., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Polyamines (PAs) are found in all living organisms and serve many vital physiological processes. In plants, PAs are ubiquitous in plant growth, physiology, reproduction, and yield. In the last decades, PAs have been studied widely for exploring their function in conferring abiotic stresses (salt, drought, and metal/metalloid toxicity) tolerance. The role of PAs in enhancing antioxidant defense mechanism and subsequent oxidative stress tolerance in plants is well-evident. However, the enzymatic regulation in PAs biosynthesis and metabolism is still under research and widely variable under various stresses and plant types. Recently, exogenous use of PAs, such as putrescine, spermidine, and spermine, was found to play a vital role in enhancing stress tolerance traits in plants. Polyamines also interact with other molecules like phytohormones, nitric oxides, trace elements, and other signaling molecules to providing coordinating actions towards stress tolerance. Due to the rapid industrialization metal/metalloid(s) contamination in the soil and subsequent uptake and toxicity in plants causes the most significant yield loss in cultivated plants, which also hamper food security. Finding the ways in enhancing tolerance and remediation mechanism is one of the critical tasks for plant biologists. In this review, we will focus the recent update on the roles of PAs in conferring metal/metalloid(s) tolerance in plants.

Salinity stress hampers the growth of most crop plants and reduces yield considerably. Therefore, experiments were conducted on wheat (Triticum aestivum L.) plants for studying the role of selenium (5 and 10 μM Se) supplementation in strengthening the salinity stress tolerance. Exposure to salinity (100 mM NaCl) reduced growth in terms of length, fresh and dry biomass yield. Se was affective in ameliorating the deleterious effects of NaCl stress to significant levels when supplied at 5 μM concentrations compared to 10 μM. Application of Se at 5 μM concentration did not show significant impacts on the physiological and biochemical parameters studied. Plants supplemented with 5 μM Se exhibited the highest RWC, chlorophyll synthesis, and photosynthesis. Se supplementation reduced the NaCl-mediated oxidative damage by up-regulating the activity of enzymatic components of the antioxidant system and the accumulation of ascorbate and glutathione. Furthermore, 5 μM Se proved beneficial in enhancing proline and sugar accumulation in normal and NaCl-stressed seedlings providing extra osmolarity to maintain RWC and protect photosynthesis. Se also affected proline metabolism by modulating the activities of the γ-glutamyl kinase (γ-GK) and proline oxidase (PROX) leading to its greater synthesis and lesser degradation. Moreover, it was observed that Se declined the Na/K ratio and also improved nitrogen and Ca uptake. Conclusively, Se at low concentration can be beneficial in preventing salinity-mediated damage and further studies are required to unravel underlying mechanisms., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Background: High and low temperatures constitute the most damaging type of abiotic stress and limit the survival, and productivity of plants. The present study aimed to evaluate the role of exogenous applications of acetylsalicylic acid (ASA) in reducing the deleterious effects of cold stress. Phaseolus vulgaris L. seedlings were treated with foliar-sprayed ASA at concentrations of 0-3 mM and then subjected to chilling stress at 4 °C for 2 or 4 days., Results: Growth, photosynthesis, biochemical alterations, oxidative damage and antioxidant enzyme activities as well as the expression of cold-responsive genes (CBF3-COR47), were monitored during the experiment. ASA applications substantially improved several growth and photosynthetic parameters, including shoot biomass, dry weight, and photosynthetic pigments, of P. vulgaris seedlings exposed to different durations of chilling stresses. The ASA foliar spray treatments significantly (p < 0.05) rescued the growth and photosynthetic pigments of P. vulgaris seedlings under different chilling stresses. The total soluble sugars markedly increased during 0-4 days of chilling stress following ASA foliar spraying. The exogenous application of ASA significantly (p < 0.05) increased the accumulation of proline in P. vulgaris seedlings under chilling stress. At the gene expression level, ASA significantly (p < 0.05) upregulated the cold-responsive genes CBF3 and COR47., Conclusions: As a result, we speculate that, the application of exogenous ASA alleviated the adverse effects of chilling stress on all measured parameters, and 1 and 2 mM ASA exhibited the greatest effects.

Foliar sprays of three plant resistance inducers, including chitosan (CH), potassium sorbate (PS) (C 6 H 7 kO 2 ), and potassium bicarbonates (PB) (KHCO 3 ), were used for resistance inducing against Erysiphe cichoracearum DC (powdery mildew) infecting okra plants. Experiments under green house and field conditions showed that, the powdery mildew disease severity was significantly reduced with all tested treatments of CH, PS, and PB in comparison with untreated control. CH at 0.5% and 0.75% (w/v) plus PS at 1.0% and 2.0% and/or PB at 2.0% or 3.0% recorded as the most effective treatments. Moreover, the highest values of vegetative studies and yield were observed with such treatments. CH and potassium salts treatments reflected many compounds of defense singles which leading to the activation power defense system in okra plant. The highest records of reduction in powdery mildew were accompanied with increasing in total phenolic, protein content and increased the activity of polyphenol oxidase, peroxidase, chitinase, and β-1,3-glucanase in okra plants. Meanwhile, single treatments of CH, PS, and PB at high concentration (0.75%, 2.0%, and/or 3.0%) caused considerable effects. Therefore, application of CH and potassium salts as natural and chemical inducers by foliar methods can be used to control of powdery mildew disease at early stages of growth and led to a maximum fruit yield in okra plants.