Mitigate Salt Stress Research Articles

A bHLH transcription factor RrUNE12 regulates salt tolerance and promotes ascorbate synthesis.

RrUNE12 binds to the RrGGP2 promoter to facilitate biosynthesis of AsA in Rosa roxburghii fruit. Furthermore, RrUNE12 upregulates antioxidant-related genes and maintains ROS homeostasis, thereby improving tolerance to salt stress. L-ascorbic acid (AsA) plays an essential role in stress defense as a major antioxidant in plant cells. GDP-L-galactose pyrophosphatase 2 (RrGGP2) has been previously identified as the key structural gene operating in AsA overproduction in Rosa roxburghii fruit. However, the transcriptional regulation of RrGGP2 in response to abiotic stress is not fully elucidated. In this study, we identified a bHLH transcription factor, RrUNE12, whose transcription level significantly correlated with RrGGP2 abundance and AsA accumulation in developing fruit. RrUNE12 is localized in the nucleus and specifically binds to the promoter of RrGGP2 to promote its transcription. The overexpression or silencing of RrUNE12 in R. roxburghii fruit and fruit callus further confirmed that RrUNE12 positively regulated RrGGP2 transcription and AsA level. Different abiotic stress treatments indicated that RrUNE12 was greatly induced by salt. Exogenous NaCl treatment on the RrUNE12-overexpressing or RrUNE12-silencing fruits also led to enhanced transcripts abundance of both RrUNE12 and RrGGP2, compared to the treatment without adding NaCl. RrUNE12 overexpression in fruit callus alleviated salt stress damage by upregulating the expression of RrGGP2 and antioxidant-related genes. Additionally, stable overexpression of RrUNE12 in tomato plants resulted in a significant increase in AsA content and antioxidant capacity, accompanied by an increased resistance to the salt stress. Collectively, the results suggest that RrUNE12 functions as an activator of AsA biosynthesis in R. roxburghii fruit and plays a positive role in mitigating salt stress by increasing both AsA level and the oxidation resistance.

Enhancing salt stress tolerance in Carthamus tinctorius L. through selenium soil treatment: anatomical, biochemical, and physiological insights

Selenium (Se) plays a crucial role in ameliorating the negative impact of abiotic stress. The present study was performed to elucidate the efficacy of soil treatment of Se in reducing salt-induced stress in Carthamus tinctorius L. In this study, three different levels of Na2SeO4 (0, 0.01, and 0.02 g kg− 1) and four levels of NaCl (0, 0.5, 1.5, and 2.5 g kg− 1) were applied. The findings revealed that while NaCl decreased seed germination parameters, growth characteristics, K+ content, relative water content (RWC), and photosynthetic pigments, it increased Na+ content, soluble carbohydrates, H2O2 content, and malondialdehyde (MDA) level. The application of Se showed a positive effect on seed germination and growth characteristics under salinity conditions, which is linked to alterations in anatomical, biochemical, and physiological factors. Anatomical studies showed that treatment with Se led to increased stem diameter, cortical parenchyma thickness, and pith diameter under salinity stress. However, variations in the thickness of the xylem and phloem did not reach statistical significance. The application of Se (0.02 g kg− 1) raised Na+ content (7.65%), K+ content (29.24%), RWC (15%), Chl a (17%), Chl b (21.73%), Chl a + b (16.9%), Car (4.22%), and soluble carbohydrates (11%) in plants subjected to NaCl (2.5 g kg− 1) stress. Furthermore, it decreased H2O2 (25.65%) and MDA (11.9%) in the shoots. The findings of the current study advocate the application of the Se-soil treating technique as an approach for salt stress mitigation in crops grown in saline conditions.

Reclassification of Salinisphaera halophila Zhang et al. 2012 as a Later Heterotypic Synonym of Salinisphaera orenii Park et al. 2012.

In the present study, the taxonomic position of Salinisphaera halophila (NZ_AYKF00000000)and Salinisphaera orenii (NZ_AYKH00000000)was re-evaluated. In addition, their metabolic potentials and mechanisms for mitigating stress conditions were determined. Comparisons of 16S rRNA gene sequences, analysis of the phylogenetic tree, phylogenomic tree, average nucleotide identity (ANI), and digital DNA-DNA hybridization (dDDH) values were conducted. The 16S rRNA gene sequence similarity between Salinisphaera halophila YIM 95161Tand Salinisphaera orenii MK-B5Twas 100%. In phylogenetic and phylogenomic trees, Salinisphaera halophila YIM 95161Tand Salinisphaera orenii MK-B5Tclustered together. Both species encode genes for glycolysis, citrate cycle, pentose phosphate pathway, Entner-Doudoroff pathway, nitrate assimilation, and assimilatory sulfate reduction. They employ salt-in and salt-out strategies to mitigate salt stress. The ANI and dDDH values between Salinisphaera halophila YIM 95161Tand Salinisphaera orenii MK-B5Twere 96.6 and 72.1%, respectively, above the cut-off (95-96% for ANI and 70% for dDDH) for species delineation. Based on the above results, we propose to reclassify Salinisphaera halophila Zhang et al. 2012 as a later heterotypic synonym of Salinisphaera orenii Park et al. 2012.

Correlation analysis of transcriptome and metabolomics and functional study of Galactinol synthase gene (VcGolS3) of blueberry under salt stress.

Soil salinity poses a significant environmental challenge for the growth and development of blueberries. However, the specific mechanisms by which blueberries respond to salt stress are still not fully understood. Here, we employed a comprehensive approach integrating physiological, metabolomic, and transcriptomic analyses to identify key metabolic pathways in blueberries under salt stress. Our findings indicate that blueberries primarily adapt to salt stress by modulating pathways associated with carbohydrate metabolism, organic acid metabolism, amino acid metabolism, and various organic compounds. Key metabolites involved in this response include sucrose, propionic acid, and palmitic acid. A total of 241 transcription factors were differentially expressed, with significant involvement from families such as AP2, Dof, GATA, WRKY, and TCP. Notably, the galactose metabolism pathway was associated with 5 DAMs and 24 DEGs, while the starch and sucrose metabolism pathway contained 5 DAMs and 23 DEGs, highlighting their crucial roles in mitigating salt stress. Overexpression of VcGolS3 in transgenic Arabidopsis conferred tolerance to salt and drought stresses, primarily evidenced by a significant increase in GolS enzyme activity and reduced ROS accumulation. This study provides valuable insights into the molecular mechanisms underlying the blueberry response to salt stress and lays the groundwork for breeding salt- and drought-tolerant blueberry varieties.

Association Analysis of the Genomic and Functional Characteristics of Halotolerant Glutamicibacter endophyticus J2-5-19 from the Rhizosphere of Suaeda salsa.

Halotolerant plant growth-promoting bacteria (HT-PGPB) have attracted considerable attention for their significant potential in mitigating salt stress in crops. However, the current exploration and development of HT-PGPB remain insufficient to meet the increasing demands of agriculture. In this study, an HT-PGPB isolated from coastal saline-alkali soil in the Yellow River Delta was identified as Glutamicibacter endophyticus J2-5-19. The strain was capable of growing in media with up to 13% NaCl and producing proteases, siderophores, and the plant hormone IAA. Under 4‱ salt stress, inoculation with strain J2-5-19 significantly increased the wheat seed germination rate from 37.5% to 95%, enhanced the dry weight of maize seedlings by 41.92%, and notably improved the development of maize root systems. Moreover, this work presented the first whole-genome of Glutamicibacter endophyticus, revealing that G. endophyticus J2-5-19 resisted salt stress by expelling sodium ions and taking up potassium ions through Na+/H+ antiporters and potassium uptake proteins, while also accumulating compatible solutes such as betaine, proline, and trehalose. Additionally, the genome contained multiple key plant growth-promoting genes, including those involved in IAA biosynthesis, siderophore production, and GABA synthesis. The findings provide a theoretical foundation and microbial resources for the development of specialized microbial inoculants for saline-alkali soils.

NO-mediated protein tyrosine nitration crosstalks with melatonin homeostasis and HO-1 activity in mitigating salt stress in sunflower seedlings

NO-mediated protein tyrosine nitration crosstalks with melatonin homeostasis and HO-1 activity in mitigating salt stress in sunflower seedlings

Effect of Nano silicon particles spraying on carnation (Dianthus caryophyllus L.) plants grown in soilless culture and irrigated with saline water

ABSTRACT The study examined the impact of salt stress on carnation plants and the efficacy of silicon dioxide nanoparticles (SiO2-NPs). Two trials manipulated salinity levels (0, 20, 40, and 60 mm) and SiO2-NPs concentrations (0, 25, and 50 mg L−1). Elevated salinity resulted in decreased growth, root development, and flowering traits while accelerating flowering time and increasing Na+ and Cl− content and superoxide dismutase (SOD) enzyme activity. Conversely, SiO2-NPs application improved growth parameters, root development, and flowering traits, enhanced leaf chemical composition and catalase (CAT) enzyme activity, and mitigated negative effects compared to the control. The 25 mg L−1 SiO2-NPs treatment proved most effective in alleviating salt stress. These findings indicate SiO2-NPs could be valuable in mitigating salt stress impacts on carnation plants.

Exogenous Oxygen Replenished as a Promising Method for Mitigating Salt Stress in Maize Seedling Stage

ABSTRACT Soil salinization is one of the main reasons for soil degradation, which limiting the improvement of soil productivity. To evaluate the response plant height, stem diameter, plant biomass and nutrient uptake of maize, and soil properties to various salt stress and oxygen supply rates, a soil culture experiment with two factors were carried out: different salt stress degrees (A0, 0 g L−1 NaCl irrigation; A3, 3 g L−1 NaCl irrigation; A6, 6 g L−1 NaCl irrigation; A9, 9 g L−1 NaCl irrigation;) and different rhizosphere oxygen supply degrees (B0, 0 ml L−1 H2O2 solution; B0.5, 0.5 ml L−1 H2O2 solution; B1, 1 ml L−1 H2O2 solution; B1.5, 1.5 ml L−1 H2O2 solution). The results showed that the plant height, stem diameter, aboveground and root biomass of maize under different salt stress degrees were reduced by 6.8–9.8%, 4.4–9.8%, 18.4–45.5% and 21.4–35.8% at the end of the experiment compared to A0, respectively. Meanwhile, the nutrient uptake of aboveground and root were declined, especially under high salt stress degree, but the sodium (Na+) uptake was increased significantly. Rhizosphere oxygen supply enhanced the plant height, stem diameter, aboveground and root biomass by 2.0–6.5%, 4.1–6.1%, 27.5–56.6% and 19.5–47.1% at the end of the experiment compared to B0, respectively. The restriction of nutrient absorption caused by salt stress could be alleviated. Soil quality indicators were influenced by salt stress and oxygen supply management as well. Overall, rhizosphere oxygen supply could alleviate the restriction of salinization on maize growth at seedling stage, improve soil chemical quality and water use efficiency.

Effect of Hormonal Priming on Mitigating Salt Stress in Tomato Plants

Effect of Hormonal Priming on Mitigating Salt Stress in Tomato Plants

Plant Growth-Promoting Yeasts (PGPYs) as a sustainable solution to mitigate salt-induced stress on zucchini plant growth

Among the long-term sustainable solutions to mitigate saline stress on plants, the use of plant growth promoting microorganisms (PGP) is considered very promising. While most of the efforts have been devoted to the selection and use of bacterial PGPs, little has been proposed with yeast PGP (PGPYs). In this study, three PGPY strains belonging to Naganishia uzbekistanensis, Papiliotrema terrestris and Solicoccozyma phenolica were employed singularly and in a consortium to mitigate salt stress of zucchini (Cucurbita pepo). The results demonstrated that these yeasts, when applied to salt-amended soil, mitigated the growth inhibition caused by NaCl. Among the three species, N. uzbekistanensis and P. terrestris showed the most significant improvements in plant performance, with N. uzbekistanensis exhibiting hormetic effects under salt stress by improving root length and dry plant biomass. In general, the root system was the most affected part of the plants due to the presence of the yeasts. The entire rhizosphere bacterial microbiota was significantly influenced by the addition of PGPYs, while the mycobiota was dominated by the introduced yeasts. Metabolomic fingerprinting using FTIR revealed modifications in hemicellulose and silica content, indicating that PGPY inoculation impacts not only the plant but also the soil and rhizosphere microorganisms.

Mitigating salt stress in Zea mays: Harnessing Serratia nematodiphila-biochar-based seed coating for plant growth promotion and rhizosphere microecology regulation

Salt stress poses a significant challenge in contemporary agricultural practices. In response, using plant growth-promoting bacteria (PGPB) in conjunction with biochar coatings has emerged as an innovative biological strategy to mitigate salt stress in crops. Through a dual screening process based on gradient salt concentration and plant growth-promoting performance, a highly salt-tolerant PGPB, Serratia nematodiphila, was identified in this study. And a seed-coating formulation incorporating S. nematodiphila was developed using biochar as a carrier. With the help of potting experiments, this paper investigated the impact of this S. nematodiphila-biochar-based seed coating on Zea mays under salt stress, while also analyzing functional alterations in the core microbial community. These findings indicate that the S. nematodiphila-biochar-based seed coating selectively enriched beneficial microbial populations, such as Proteobacteria, Gammaproteobacteria, Verrucomicrobiae, and Bacteroidia, fostering a symbiotic association with the Z. mays root system. These beneficial consortia facilitated the accumulation of osmotic solutes, including soluble sugars, soluble proteins, and proline, thereby modulating leaf photosynthetic activity and alleviating salt stress (sodium and potassium homeostasis) in Z. mays. This investigation provides refined technical approaches for alleviating salt stress in Z. mays, contributing to developing sustainable agricultural practices.

The biocontrol strain Bacillus mojavensis KRS009 confers resistance to cotton Verticillium wilt and improves tolerance to salt stress

AbstractBiological control has gained increasing attention as a strategy to address biotic and abiotic stresses in crops. In this study, we identified the strain KRS009 as Bacillus mojavensis through morphological identification and multilocus sequence analysis. KRS009 exhibited broad‐spectrum antifungal activity against various phytopathogenic fungi by secreting soluble and volatile compounds. Additionally, the physio‐biochemical traits of strain KRS009 were characterized, including its growth‐promoting capabilities and active enzymes. Notably, KRS009 demonstrated the capacity for biofilm formation and exhibited tolerance to saline‐alkali conditions. The biological security evaluation confirmed the safety of KRS009 for both humans and plants. Furthermore, strain KRS009 was found to trigger plant immunity by inducing systemic resistance through salicylic acid‐ and jasmonic acid‐dependent signaling pathways. Greenhouse experiments conducted on cotton plants proved that the treatment with strain KRS009 effectively protected cotton against Verticillium wilt caused by Verticillium dahliae and promoted the growth of cotton under salt stress. These findings highlight the potential of B. mojavensis KRS009 as a promising biocontrol and biofertilizer agent for promoting plant growth, combating fungal diseases and mitigating salt stress in plants.

A Sustainable Methodological Approach for mitigation of Salt Stress of Rice Seedlings in Coastal Regions: Identification of Halotolerant Rhizobacteria from Noakhali, Bangladesh and their impact

Salinity hinders the growth of many crops common in the diet, such as rice, wheat and maize when cultivated in coastal salinity areas. Given the limited availability of cultivable land and the increasing growth of the population, it is necessary to enhance productivity. In this paper, we present an innovative approach to adopting Halotolerant Plant Growth Promoting Rhizobacteria (HPGPR) to enhance salt-tolerant rice varieties to solve salinity stress and enhance crop production. HPGPR has functions to overcome plant growth and development and is the most efficient bioinoculant for rice in saline environments. This approach can be considered a potential method because of the cost-effective and environmentally friendly impacts in agricultural production, which involves salt-affected areas.

Mitigating salt stress in “Friariello Napoletano” (Brassica rapa subsp. sylvestris L. Janch. var. esculenta Hort.): The potential of biochar for sustainable agriculture

The agricultural sector is therefore called upon to seek efficient and sustainable strategies to improve plant resilience and tolerance to sub-optimal growth conditions. In many coastal areas of the Mediterranean, saline stress causes serious problems to vegetable crops. In this scenario, the use of upgraded agrochemicals such as plant biostimulants, biochar and plant nutrition regulators could be beneficial. The aim of the study was to evaluate the effects of amending the soil with different concentrations of poplar-derived biochar (0 %, 1 % and 2 % by volume), on the productive and qualitative response of an ecotype of “Friariello Napoletano” (Brassica rapa subsp. sylvestris L. Janch. var. esculenta Hort.) under different levels of saline irrigation (0, 30, 60 and 120 mM NaCl, giving an electrical conductivity values of 0.05, 2.09, 6.09 and 9.70 dS m–1). The experiment was conducted in an unheated greenhouse, using pot plants grown in soil with a randomized complete-block experimental design arranged in a 4 × 3 factorial scheme with three replications. Productive and physiological results (ACO2, gs, E, SPAD index) highlighted a highly glycophytic response of Friariello. Biochar integration, besides increasing total production and glucosinolate content, led to a significant reduction in toxic ion content (Na+and Cl−) under saline conditions compared to control plants. Regardless of salinity effect, the application of biochar resulted in an increase in fresh yield and photosynthetic activity (ACO2) of 12.8 % and 29.3 % respectively. The promising results underscore the potential role of biochar as a sustainable strategy for mitigating salt stress in Friariello Napoletano and potentially other vegetable crops in salt-affected regions. However, it needs to be clarified which adaptive mechanisms triggered by biochar improves production performance even and especially under sub-optimal growing conditions.

Exogenous paclobutrazol effectively mitigates salt stress in ‘Duli’ (Pyrus betulifolia) seedlings by reducing Na+/K+ ratio, improving their osmotic substances, and activating the expression level of SOS and ABA pathway genes

Soil salinization is responsible for reductions in soil utilization by plants. Paclobutrazol (PAC) is an important plant growth regulator that is responsive to multiple biotic and abiotic stresses. In this study, we measured the impact of salt stress and PAC treatments on the growth, physiology, transcriptome, and related genes expression level of ‘Duli’ (Pyrus betulifolia). Our results show that NP treatment (200 mM NaCl + 10 μM PAC) improves this plant's morphological characters, decreases its Na+ content and Na+/K+ ratio from 9.33 % to 22.48 % compared to the NT (200 mM NaCl), increases its antioxidant enzyme activity, and inhibits its active oxygen as well as malondialdehyde content, and enables it to accumulate osmotic adjustment substances (i.e., proline and soluble sugar). NP treatment slows down chlorophyll degradation and regulation of endogenous hormones to safeguard photosynthesis. Further, combining the RNA–seq and q–PCR results reveals that NP increases the expression of salt overly sensitive (SOS) genes (SOS1, SOS2, SOS3), ion transporter (PbANN1, PbAKT), ABA receptor PbPYLs, and transcription factors (PbNAC, PbWRKY). In conclusion, this study's findings demonstrates that exogenous PAC is effective at countering salt stress–induced damage to ‘Duli’ seedlings, which can be applied to improve ‘Duli’ salt tolerance in pear production.

Mitigation of Salt Stress in Lactuca sativa L. var. Gentile Rossa Using Microalgae as Priming Agents.

Using renewable biomass in agriculture, particularly microalgae as a biostimulant, offers economic and environmental sustainability benefits by reducing costs, improving nutrient cycling, and enhancing water use efficiency. Microalgae contain bioactive compounds that boost crop tolerance to environmental stresses, including salinity. Saline soils, characterized by elevated sodium chloride (NaCl) levels, negatively impact many crops, resulting in low productivity and high remediation costs. Therefore, this study evaluates the biostimulant properties of a microalgae-based commercial preparation (MR) on lettuce (Lactuca sativa L.) plants grown hydroponically and exposed to saline stress. The extract was chemically characterized through elemental analysis, lipid composition (gas chromatography with flame ionization detector-GC-FID), the determination of functional groups (Fourier Transformed Infrared-FT-IR), structure (1H,13C Nuclear Magnetic Resonance-NMR), with their hormone-like activity also assessed. Lettuce plants were treated with or without the microalgae blend, in combination with 0, 50 mM, or 100 mM NaCl. The contents of nutrients, soluble proteins, chlorophylls, and phenols, as well as the lipid peroxidation, antioxidants and root traits of lettuce plants, were estimated. The microalgae applied to salt-stressed plants resulted in a significant increase in biomass, protein, and chlorophyll contents. Additionally, significant effects on the secondary metabolism and mitigation of salinity stress were observed in terms of increased phenol content and the activity of antioxidant enzymes, as well as decreased lipid peroxidation. The potassium (K+) content was increased significantly in plants treated with 100 mM NaCl after addition of microalgae, while the content of sodium (Na+) was concurrently reduced. In conclusion, our results demonstrate that using microalgae can be a potent approach for improving the cultivation of Lactuca sativa L. under saline stress conditions.

Optimizing Tomato (Lycopersicon esculentum) Yield Under Salt Stress: The Physiological and Biochemical Effects of Foliar Thiourea Application.

A pot experiment was conducted to investigate the role of thiourea exogenous application (0 mg/L and 100 mg/L) on the morphological, physiological, and yield traits of two varieties of tomato (Naqeeb and Nadir) under different salt stress treatments (0, 60, and 120 mM) in completely randomized design (CRD). The imposition of salinity by rooting medium showed that salt stress reduced plant height by 20%, fresh shoot weight by 50%, dry shoot weight by 78%, fresh root weight by 43%, dry root weight by 84%, root length by 34%, shoot length by 32%, shoot K+ by 47%, Ca2+ by 70%, chlorophyll a by 30%, chlorophyll b by 67%, and the number of seeds per berry by 53%, while shoot Na+ ions were increased by 90% in comparison to those grown with control treatment. However, the exogenous application of thiourea significantly enhanced dry root weight by 25% and the number of seeds per berry by 20% in comparison to untreated plants with thiourea when grown under salt stress. Salt stress resulted in a reduction in the number of berries, weight per berry, number of seeds per berry, and seed weight in both varieties, while thiourea foliar application increased these yield parameters. On the other hand, the Nadir variety surpassed Naqeeb in plant height (+13%), root length (+31%) and shoot length (+11%), fresh shoot weight (+42%) and dry shoot weight (+11%), fresh root weight (+29%), dry root weight (+25%), area of leaf (+26%), chlorophyll a (+32%), and chlorophyll b (+24%). In conclusion, the exogenous application of thiourea can be used to mitigate salt stress in tomato plants since it can improve the growth, physiological, and yield traits of this strategic crop.

Modulations in Physiological and Biochemical attributes of Citrus Limon by selenium nanoparticles (SeNPs) under salinity stress

Salinity is recognized as a significant abiotic stressor that impairs crop growth and productivity. Elevated - soil and irrigation water salinity poses substantial ecological challenges for agriculture, particularly in semiarid and arid regions. High sodium (Na+) concentrations induce osmotic stress, leading to water deficits within plant cells. However, using nanoparticles can mitigate salt stress and enhance plant growth. This study investigates the effects of selenium nanoparticles on the physiobiochemical characteristics of Citrus limon L. seedlings under salt stress. Selenium nanoparticles act as both reducing and capping agents. Six-month-old lemon seedlings were subjected to varying salinity levels (100 mM and 200 mM NaCl) and treated with foliar applications of selenium nanoparticles at - 25 mg/L and 50 mg/L concentration. Most of the nanostructures were observed in the size range of 20–40 nm and anisotropic and irregular in shape. The results indicated that 200 mM NaCl significantly reduced the morphological and physio-biochemical parameters of the seedlings. However, a 50 mg/L concentration of SeNPs notably improved fresh and dry weights of roots and shoots and increased chlorophyll content. Biochemical attributes such as SOD, POD, CAT, APX, TSS, TFA, Proline, H2O2, and MDA were elevated under 200 mM NaCl, while NPK levels decreased. A concentration of 50 mg/L SeNPs was identified as optimal for enhancing the morphological and physiobiochemical parameters of C. limon seedlings under salt stress.

Calcium Silicate Application as a Salt Stress Mitigation Strategy for Vegetables in the Salt-affected Soils of Sandy Plains of Kerala, India

Soil salinity inhibits plant growth due to osmotic stress and reduced plant and water uptake. In the Onattukara sandy plains of Kerala, saltwater intrusion is a major problem in several panchayaths near the coastal area. In uplands also, cultivation is not possible due to the salt stress from saltwater intrusion. One of the strategies for removing the inhibitory effect of salt stress on plant growth is the application of beneficial nutrients to the plants. Therefore, a study was carried out to understand the effect of calcium silicate application on mitigating salt stress in vegetables and using tomato as a test crop. A detailed germination study was conducted in laboratory conditions prior to pot culture experiment to find out the critical level of salinity for tomato and two salinity levels 30mM and 40 mM NaCl were selected for the pot culture experiment. For accessing the effect of the various levels of calcium silicate on reducing salt stress in tomato, a pot culture experiment was conducted in Onattukara region (AEU 3) in completely randomized design with ten treatments replicated thrice with varying levels of CaSiO3 from 100 kg ha-1 to 150 kg ha-1. The treatments had a significant effect on all the biometric characteristics and yield attributes of the crop. The highest fruit weight, fruit per plant, and fruit yield were observed in treatment with soil test-based NPK recommendation and 125 kg ha-1 of CaSiO3 applied. It was also observed that the relative water content was higher and the water saturation deficit was lower in this treatment. CaSiO3 application @125 kg ha-1 along with soil test-based recommendation of NPK can be recommended as a salt stress mitigation strategy for boosting vegetable production in the salt-affected soils of sandy plains of Kerala.

Brassinosteroids Alleviate Salt Stress by Enhancing Sugar and Glycine Betaine in Pepper (Capsicum annuum L.).

Salt stress is a major abiotic factor that negatively impacts the growth, performance, and secondary metabolite production in pepper (Capsicum annuum L.) plants. Brassinosteroids (BRs) play a crucial role in enhancing plant tolerance to abiotic stress, yet their potential in mitigating salt stress in pepper plants, particularly by promoting sugar and glycine betaine accumulation, remains underexplored. In this study, we investigated the effects of the foliar application of 2,4-epibrassinolide (EBR) on salt-stressed pepper seedlings. Our findings revealed that EBR treatment significantly increased the levels of proline, sugar, and glycine betaine under salt stress compared to untreated controls. Moreover, EBR enhanced the antioxidant defense mechanisms in pepper seedlings by increasing sugar and glycine betaine levels, which contributed to the reduction of reactive oxygen species (ROS) and malondialdehyde (MDA) accumulation.