Overexpression of Peroxidase Gene GsPRX9 Confers Salt Tolerance in Soybean

Peroxidases play prominent roles in antioxidant responses and stress tolerance in plants; however, their functions in soybean tolerance to salt stress remain unclear. Here, we investigated the role of a peroxidase gene from the wild soybean (Glycine soja), GsPRX9, in soybean tolerance to salt stress. GsPRX9 gene expression was induced by salt treatment in the roots of both salt-tolerant and -sensitive soybean varieties, and its relative expression level in the roots of salt-tolerant soybean varieties showed a significantly higher increase than in salt-sensitive varieties after NaCl treatment, suggesting its possible role in soybean response to salt stress. GsPRX9-overexpressing yeast (strains of INVSc1 and G19) grew better than the control under salt and H2O2 stress, and GsPRX9-overexpressing soybean composite plants showed higher shoot fresh weight and leaf relative water content than control plants after NaCl treatment. Moreover, the GsPRX9-overexpressing soybean hairy roots had higher root fresh weight, primary root length, activities of peroxidase and superoxide dismutase, and glutathione level, but lower H2O2 content than those in control roots under salt stress. These findings suggest that the overexpression of the GsPRX9 gene enhanced the salt tolerance and antioxidant response in soybean. This study would provide new insights into the role of peroxidase in plant tolerance to salt stress.

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Exogenous Melatonin Improves Salt Tolerance by Mitigating Osmotic, Ion, and Oxidative Stresses in Maize Seedlings

Agronomy ◽

10.3390/agronomy10050663 ◽

2020 ◽

Vol 10 (5) ◽

pp. 663 ◽

Cited By ~ 3

Author(s):

Jianhong Ren ◽

Jun Ye ◽

Lina Yin ◽

Gouxia Li ◽

Xiping Deng ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Antioxidant Activities ◽

Term Treatment ◽

Plant Tolerance ◽

Short Term Treatment ◽

Exogenous Melatonin ◽

Positive Effects ◽

Oxidative Stresses

Melatonin has been confirmed extensively for the positive effects on increasing plant tolerance to various abiotic stresses. However, the roles of melatonin in mediating different stresses still need to be explored in different plants species and growth periods. To investigate the role of melatonin in mitigating salt stress, maize (Zea mays L.) seedlings growing in hydroponic solution were treated with 100 mM NaCl combined with or without 1 μM melatonin. Melatonin application had no effects on maize growth under normal condition, while it moderately alleviated the NaCl-induced inhibition of plant growth. The leaf area, biomass, and photosynthesis of melatonin-treated plants were higher than that of without melatonin under NaCl treatment. The osmotic potential was lower, and the osmolyte contents (including sucrose and fructose) were higher in melatonin-treated plants. Meanwhile, the decreases in Na+ content and increases in K+/Na+ ratio were found in shoots of melatonin-applied plant under salt stress. Moreover, both enzymatic and nonenzymatic antioxidant activities were significantly increased in leaves with melatonin application under salt treatment. These results clearly indicate that the exogenous melatonin-enhanced salt tolerance under short-term treatment could be ascribed to three aspects, including osmotic adjustment, ion balance, and alleviation of salt-induced oxidative stress.

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Large-scale integrated evaluation of salt tolerance in japonica rice at the germination stage

10.21203/rs.2.23104/v1 ◽

2020 ◽

Author(s):

Xiu Jing ◽

Ping Mi ◽

Xianzhi Xie ◽

Baoshan Wang

Keyword(s):

Mathematical Model ◽

Salt Stress ◽

Salt Tolerance ◽

Large Scale ◽

Crop Yields ◽

Japonica Rice ◽

Rice Cultivars ◽

Salt Tolerant ◽

Fresh Weight ◽

Germination Stage

Abstract Background: Salt stress, one of the most important abiotic stresses, severely reduces crop yields. Identifying salt-tolerant rice germplasm resources at the germination stage, developing salt tolerance indicators, and cultivating salt-tolerant rice cultivars are crucial for improving rice production in saline soil.Results: We measured the germination parameters of 140 japonica rice cultivars on the 7 day after sowing (DAS) in 0 and 150 mmol L−1 NaCl. To accurately assess salt tolerance and identify reliable indicators of salt tolerance, we measured the shoot length (SL), root length (RL), root fresh weight (RFW), shoot fresh weight (SFW), total fresh weight (TFW) and salt tolerance (STI) index after 7 days of salt-stress treatment. The 140 rice cultivars were divided into four categories based on the mean MFVs: highly salt tolerant (HST: 19 cultivars), salt tolerant (ST: 74 cultivars), weakly salt tolerant (WST: 43 cultivars), and salt sensitive (SS: 4 cultivars). Based on the physiological indicators, we established a mathematical model to accurately evaluate salt tolerance in japonica rice cultivars. STI of TFW under 150 mmol L−1 NaCl treatment showed the highest correlation with salt tolerance during the germination stage.Conclusions: We determined the optimum NaCl concentration (150 mmol L−1) for evaluating salt tolerance in japonica rice at the germination stage. We identified 19 HST, 74 ST, 43 WST, and 4 SS japonica rice cultivars during the germination stage and proposed a mathematical model to evaluate salt tolerance. STI of TFW is a reliable, accurate indicator for evaluating salt tolerance in japonica rice. These findings should greatly facilitate the evaluation of japonica rice cultivars during seed germination and the breeding of salt-tolerant rice cultivars.

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Identification and Characterization of Wheat Germplasm for Salt Tolerance

Plants ◽

10.3390/plants10020268 ◽

2021 ◽

Vol 10 (2) ◽

pp. 268

Author(s):

Xiaoyan Quan ◽

Xiaoli Liang ◽

Hongmei Li ◽

Chunjuan Xie ◽

Wenxing He ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Redox Homeostasis ◽

Soluble Sugars ◽

Dry Weight ◽

Limiting Factors ◽

Salt Tolerant ◽

Fresh Weight ◽

Shoot Height ◽

Wheat Genotypes

Salinity is one of the limiting factors of wheat production worldwide. A total of 334 internationally derived wheat genotypes were employed to identify new germplasm resources for salt tolerance breeding. Salt stress caused 39, 49, 58, 55, 21 and 39% reductions in shoot dry weight (SDW), root dry weight (RDW), shoot fresh weight (SFW), root fresh weight (RFW), shoot height (SH) and root length (RL) of wheat, respectively, compared with the control condition at the seedling stage. The wheat genotypes showed a wide genetic and tissue diversity for the determined characteristics in response to salt stress. Finally, 12 wheat genotypes were identified as salt-tolerant through a combination of one-factor (more emphasis on the biomass yield) and multifactor analysis. In general, greater accumulation of osmotic substances, efficient use of soluble sugars, lower Na+/K+ and a higher-efficiency antioxidative system contribute to better growth in the tolerant genotypes under salt stress. In other words, the tolerant genotypes are capable of maintaining stable osmotic potential and ion and redox homeostasis and providing more energy and materials for root growth. The identified genotypes with higher salt tolerance could be useful for developing new salt-tolerant wheat cultivars as well as in further studies to underline the genetic mechanisms of salt tolerance in wheat.

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Ectopic Expression of Gs5PTase8, a Soybean Inositol Polyphosphate 5-Phosphatase, Enhances Salt Tolerance in Plants

International Journal of Molecular Sciences ◽

10.3390/ijms21031023 ◽

2020 ◽

Vol 21 (3) ◽

pp. 1023 ◽

Cited By ~ 2

Author(s):

Qi Jia ◽

Song Sun ◽

Defeng Kong ◽

Junliang Song ◽

Lumei Wu ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Stress Responses ◽

Transgenic Arabidopsis ◽

Glycine Soja ◽

Critical Role ◽

Ectopic Expression ◽

Wild Soybean ◽

Inositol Polyphosphate ◽

Wild Type

Inositol polyphosphate 5-phosphatases (5PTases) function in inositol signaling by regulating the catabolism of phosphoinositol derivatives. Previous reports showed that 5PTases play a critical role in plant development and stress responses. In this study, we identified a novel 5PTase gene, Gs5PTase8, from the salt-tolerance locus of chromosome 3 in wild soybean (Glycine soja). Gs5PTase8 is highly up-regulated under salt treatment. It is localized in the nucleus and plasma membrane with a strong signal in the apoplast. Ectopic expression of Gs5PTase8 significantly increased salt tolerance in transgenic BY-2 cells, soybean hairy roots and Arabidopsis, suggesting Gs5PTase8 could increase salt tolerance in plants. The overexpression of Gs5PTase8 significantly enhanced the activities of catalase and ascorbate peroxidase under salt stress. The seeds of Gs5PTase8-transgenic Arabidopsis germinated earlier than the wild type under abscisic acid treatment, indicating Gs5PTase8 would alter ABA sensitivity. Besides, transcriptional analyses showed that the stress-responsive genes, AtRD22, AtRD29A and AtRD29B, were induced with a higher level in the Gs5PTase8-transgenic Arabidopsis plants than in the wild type under salt stress. These results reveal that Gs5PTase8 play a positive role in salt tolerance and might be a candidate gene for improving soybean adaptation to salt stress.

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Genetic Potential for Salt Tolerance During Germination in Lycopersicon Species

HortScience ◽

10.21273/hortsci.32.2.296 ◽

1997 ◽

Vol 32 (2) ◽

pp. 296-300 ◽

Cited By ~ 46

Author(s):

M.R. Foolad ◽

G.Y. Lin

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Genotypic Variation ◽

Control Treatment ◽

Molar Ratio ◽

Wild Accession ◽

Salt Tolerant ◽

Plant Introductions ◽

Genetic Potential ◽

Stress Levels

Seed of 42 wild accessions (Plant Introductions) of Lycopersicon pimpinellifolium Jusl., 11 cultigens (cultivated accessions) of L. esculentum Mill., and three control genotypes [LA716 (a salt-tolerant wild accession of L. pennellii Corr.), PI 174263 (a salt-tolerant cultigen), and UCT5 (a salt-sensitive breeding line)] were evaluated for germination in either 0 mm (control) or 100 mm synthetic sea salt (SSS, Na+/Ca2+ molar ratio equal to 5). Germination time increased in response to salt-stress in all genotypes, however, genotypic variation was observed. One accession of L. pimpinellifolium, LA1578, germinated as rapidly as LA716, and both germinated more rapidly than any other genotype under salt-stress. Ten accessions of L. pimpinellifolium germinated more rapidly than PI 174263 and 35 accessions germinated more rapidly than UCT5 under salt-stress. The results indicate a strong genetic potential for salt tolerance during germination within L. pimpinellifolium. Across genotypes, germination under salt-stress was positively correlated (r = 0.62, P < 0.01) with germination in the control treatment. The stability of germination response at diverse salt-stress levels was determined by evaluating germination of a subset of wild, cultivated accessions and the three control genotypes at 75, 150, and 200 mm SSS. Seeds that germinated rapidly at 75 mm also germinated rapidly at 150 mm salt. A strong correlation (r = 0.90, P < 0.01) existed between the speed of germination at these two salt-stress levels. At 200 mm salt, most accessions (76%) did not reach 50% germination by 38 days, demonstrating limited genetic potential within Lycopersicon for salt tolerance during germination at this high salinity.

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Exogenous melatonin improves the salt tolerance of cotton by removing active oxygen and protecting photosynthetic organs

BMC Plant Biology ◽

10.1186/s12870-021-03082-7 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Dan Jiang ◽

Bin Lu ◽

Liantao Liu ◽

Wenjing Duan ◽

Yanjun Meng ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Oxidative Damage ◽

Photosynthetic Capacity ◽

Photochemical Efficiency ◽

Photochemical Quenching ◽

Plant Tolerance ◽

Signal Molecule ◽

Ion Balance ◽

Photosynthetic System

Abstract Background As damage to the ecological environment continues to increase amid unreasonable amounts of irrigation, soil salinization has become a major challenge to agricultural development. Melatonin (MT) is a pleiotropic signal molecule and indole hormone, which alleviates the damage of abiotic stress to plants. MT has been confirmed to eliminate reactive oxygen species (ROS) by improving the antioxidant system and reducing oxidative damage under adversity. However, the mechanism by which exogenous MT mediates salt tolerance by regulating the photosynthetic capacity and ion balance of cotton seedlings still remains unknown. In this study, the regulatory effects of MT on the photosynthetic system, osmotic modulators, chloroplast, and anatomical structure of cotton seedlings were determined under 0–500 μM MT treatments with salt stress induced by treatment with 150 mM NaCl. Results Salt stress reduces the chlorophyll content, net photosynthetic rate, stomatal conductance, intercellular CO2 concentration, transpiration rate, PSII photochemical efficiency, PSII actual photochemical quantum yield, the apparent electron transfer efficiency, stomata opening, and biomass. In addition, it increases non-photochemical quenching. All of these responses were effectively alleviated by exogenous treatment with MT. Exogenous MT reduces oxidative damage and lipid peroxidation by reducing salt-induced ROS and protects the plasma membrane from oxidative toxicity. MT also reduces the osmotic pressure by reducing the salt-induced accumulation of Na+ and increasing the contents of K+ and proline. Exogenous MT can facilitate stomatal opening and protect the integrity of cotton chloroplast grana lamella structure and mitochondria under salt stress, protect the photosynthetic system of plants, and improve their biomass. An anatomical analysis of leaves and stems showed that MT can improve xylem and phloem and other properties and aides in the transportation of water, inorganic salts, and organic substances. Therefore, the application of MT attenuates salt-induced stress damage to plants. Treatment with exogenous MT positively increased the salt tolerance of cotton seedlings by improving their photosynthetic capacity, stomatal characteristics, ion balance, osmotic substance biosynthetic pathways, and chloroplast and anatomical structures (xylem vessels and phloem vessels). Conclusions Our study attributes help to protect the structural stability of photosynthetic organs and increase the amount of material accumulation, thereby reducing salt-induced secondary stress. The mechanisms of MT-induced plant tolerance to salt stress provide a theoretical basis for the use of MT to alleviate salt stress caused by unreasonable irrigation, fertilization, and climate change.

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Physiological and transcriptomic analyses reveal the mechanisms underlying the salt tolerance of Zoysia japonica Steud.

10.21203/rs.2.16313/v3 ◽

2020 ◽

Author(s):

Jingjing Wang ◽

Cong An ◽

Hailin Guo ◽

Xiangyang Yang ◽

Jingbo Chen ◽

...

Keyword(s):

Signal Transduction ◽

Salt Stress ◽

Stress Response ◽

Salt Tolerance ◽

Molecular Mechanisms ◽

Salt Tolerant ◽

Zoysia Japonica ◽

Salt Stress Response ◽

Leaves And Roots ◽

Time Point

Abstract Background: Areas with saline soils are sparsely populated and have fragile ecosystems, which severely restricts the sustainable development of local economies. Zoysia grasses are recognized as excellent warm-season turfgrasses worldwide, with high salt tolerance and superior growth in saline-alkali soils. However, the mechanism underlying the salt tolerance of Zoysia species remains unknown. Results: The phenotypic and physiological responses of two contrasting materials, Zoysia japonica Steud. Z004 (salt sensitive) and Z011 (salt tolerant) in response to salt stress were studied. The results show that Z011 was more salt tolerant than was Z004, with the former presenting greater K+/Na+ ratios in both its leaves and roots. To study the molecular mechanisms underlying salt tolerance further, we compared the transcriptomes of the two materials at different time points (0 h, 1 h, 24 h, and 72 h) and from different tissues (leaves and roots) under salt treatment. The 24-h time point and the roots might make significant contributions to the salt tolerance. Moreover, GO and KEGG analyses of different comparisons revealed that the key DEGs participating in the salt-stress response belonged to the hormone pathway, various TF families and the DUF family. Conclusions: Z011 may have improved salt tolerance by reducing Na+ transport from the roots to the leaves, increasing K+ absorption in the roots and reducing K+ secretion from the leaves to maintain a significantly greater K+/Na+ ratio. Twenty-four hours might be a relatively important time point for the salt-stress response of zoysiagrass. The auxin signal transduction family, ABA signal transduction family, WRKY TF family and bHLH TF family may be the most important families in Zoysia salt-stress regulation. This study provides fundamental information concerning the salt-stress response of Zoysia and improves the understanding of molecular mechanisms in salt-tolerant plants.

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The full-length transcriptome of Spartina alterniflora reveals the complexity of high salt tolerance in monocotyledonous halophyte

10.1101/680819 ◽

2019 ◽

Cited By ~ 2

Author(s):

Wenbin Ye ◽

Taotao Wang ◽

Wei Wei ◽

Shuaitong Lou ◽

Faxiu Lan ◽

...

Keyword(s):

Gene Expression ◽

Salt Stress ◽

Alternative Splicing ◽

Salt Tolerance ◽

Protein Kinases ◽

Spartina Alterniflora ◽

High Salt ◽

Full Length ◽

Salt Tolerant ◽

High Salt Tolerance

ABSTRACTSpartina alterniflora (Spartina) is the only halophyte in the salt marsh. However, the molecular basis of its high salt tolerance remains elusive. In this study, we used PacBio full-length single molecule long-read sequencing and RNA-seq to elucidate the transcriptome dynamics of high salt tolerance in Spartina by salt-gradient experiments (0, 350, 500 and 800 mM NaCl). We systematically analyzed the gene expression diversity and deciphered possible roles of ion transporters, protein kinases and photosynthesis in salt tolerance. Moreover, the co-expression network analysis revealed several hub genes in salt stress regulatory networks, including protein kinases such as SaOST1, SaCIPK10 and three SaLRRs. Furthermore, high salt stress affected the gene expression of photosynthesis through down-regulation at the transcription level and alternative splicing at the post-transcriptional level. In addition, overexpression of two Spartina salt-tolerant genes SaHSP70-I and SaAF2 in Arabidopsis significantly promoted the salt tolerance of transgenic lines. Finally, we built the SAPacBio website for visualizing the full-length transcriptome sequences, transcription factors, ncRNAs, salt-tolerant genes, and alternative splicing events in Spartina. Overall, this study sheds light on the high salt tolerance mechanisms of monocotyledonous-halophyte and demonstrates the potential of Spartina genes for engineering salt-tolerant plants.

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Effect of Sulfur and Clean Salt on Antioxidant Enzymes and Proline Content in Improving Salt Tolerance of Two Lettuce Cultivars Grown in Basrah

Basrah Journal of Agricultural Sciences ◽

10.37077/25200860.2019.142 ◽

2019 ◽

Vol 32 ◽

pp. 80-89

Author(s):

Jameel H. Hiji ◽

Abbas M. Jasim ◽

Awatif N. Jerry

Keyword(s):

Electrical Conductivity ◽

Antioxidant Enzymes ◽

Salt Tolerance ◽

Adverse Effects ◽

Irrigation Water ◽

Sandy Loam ◽

Proline Content ◽

Salt Tolerant ◽

Loam Soil

The experiment was conducted during 2017-2018 and 2018-2019 winter seasons at Abu Al-Khaseeb District at basrah /Iraq on sandy loam soil to study the effect of sulfur at five concentration ( 0 , 500 , 1000, 1500 and 2000) kg. Ha-1, clean salt at three concentration (0, 0.5 and 1.0) ml. L-1, two cultivars of lettuce local and fajr and interaction among them at electrical conductivity of the irrigation water (7.85 and 9.69) dS.m-1. Result showed significant reduction in the activity of catalase (CAT) and peroxidase (POD) enzymes and proline content in all treatments of sulfur and clean salt especially at 2000 Kg. Ha-1 sulfur and clean salt at 1.0 ml L-1had significantly decrease in CAT activity (295.80 ? 341.65) U mg–1 FW, POD activity (7.86? 8.98) U mg–1 FW and proline (0.50 ? 0.80) mg g-1DW, comparing with control of CAT activity (663.21, 814.65) U mg–1 FW and POD activity (13.83, 15.52) mg–1 FW and proline (1.19, 2.03) mg g-1DW, respectively for two seasons due to the role of sulfur and clean salt ameliorates the adverse effects of salinity on plants. Fajr lettuce is more salt-tolerant than local due to less antioxidant enzyme levels POD, CAT and proline.

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Beyond the greenhouse: coupling environmental and salt stress response reveals unexpected global transcriptional regulatory networks in Salicornia bigelovii

10.1101/2020.03.17.995720 ◽

2020 ◽

Author(s):

Houda Chelaifa ◽

Manikandan Vinu ◽

Massar Dieng ◽

Youssef Idaghdour ◽

Ayesha Hasan ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Model Systems ◽

Biofuel Production ◽

Salt Tolerant ◽

Plant Model ◽

Tissue Specific ◽

Stress Regulation ◽

Salicornia Bigelovii ◽

Tolerant Plant

AbstractSoil salinity is an increasing threat to global food production systems. As such, there is a need for salt tolerant plant model systems in order to understand salt stress regulation and response. Salicornia bigelovii, a succulent obligatory halophyte, is one of the most salt tolerant plant species in the world. It possesses distinctive characteristics that make it a candidate plant model for studying salt stress regulation and tolerance, showing promise as an economical non-crop species that can be used for saline land remediation and for large-scale biofuel production. However, available S. bigelovii genomic and transcriptomic data are insufficient to reveal its molecular mechanism of salt tolerance. We performed transcriptome analysis of S. bigelovii flowers, roots, seeds and shoots tissues cultivated under desert conditions and irrigated with saline aquaculture effluent. We identified a unique set of tissue specific transcripts present in this non-model crop. A total of 66,943 transcripts (72.63%) were successfully annotated through the GO database with 18,321 transcripts (27.38%) having no matches to known transcripts. Excluding non-plant transcripts, differential expression analysis of 49,914 annotated transcripts revealed differentially expressed transcripts (DETs) between the four tissues and identified shoots and flowers as the most transcriptionally similar tissues relative to roots and seeds. The DETs between above and below ground tissues, with the exclusion of seeds, were primarily involved in osmotic regulation and ion transportation. We identified DETs between shoots and roots implicated in salt tolerance including SbSOS1, SbNHX, SbHKT6 upregulated in shoots relative to roots, while aquaporins (AQPs) were up regulated in roots. We also noted that DETs implicated in osmolyte regulation exhibit a different profile among shoots and roots. Our study provides the first report of a highly upregulated HKT6 from S. bigelovii shoot tissue. Furthermore, we identified two BADH transcripts with divergent sequence and tissue specific expression pattern. Overall, expression of the ion transport transcripts suggests Na+ accumulation in S. bigelovii shoots. Our data led to novel insights into transcriptional regulation across the four tissues and identified a core set of salt stress-related transcripts in S. bigelovii.

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