scholarly journals Responses to Salinity in Four Plantago Species from Tunisia

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1392
Author(s):  
Hela Belhaj Ltaeif ◽  
Anis Sakhraoui ◽  
Sara González-Orenga ◽  
Anbu Landa Faz ◽  
Monica Boscaiu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Salt Stress ◽  
Stress Responses ◽  
High Salinity ◽  
Plantago Ovata ◽  
Stress Markers ◽  
As Species ◽  
Nacl Concentration ◽  
Antioxidant Metabolites ◽  
Mechanisms Of Salt Tolerance

The genus Plantago is particularly interesting for studying the mechanisms of salt tolerance in plants, as it includes both halophytes and glycophytes, as well as species adapted to xeric environments. In this study, the salt stress responses of two halophytes, P. crassifolia and P. coronopus, were compared with those of two glycophytes, P. ovata and P. afra. Plants obtained by seed germination of the four species, collected in different regions of Tunisia, were subjected to increasing salinity treatments for one month under greenhouse conditions. Morphological traits and biochemical parameters, such as ion accumulation and the leaf contents of photosynthetic pigments, osmolytes, oxidative stress markers and antioxidant metabolites, were measured after the treatments. Salt-induced growth inhibition was more pronounced in P. afra, and only plants subjected to the lowest applied NaCl concentration (200 mM) survived until the end of the treatments. The biochemical responses were different in the two groups of plants; the halophytes accumulated higher Na+ and proline concentrations, whereas MDA levels in their leaves decreased, indicating a lower level of oxidative stress. Overall, the results showed that P. coronopus and P. crassifolia are the most tolerant to salt stress, and P. afra is the most susceptible of the four species. Plantago ovata is also quite resistant, apparently by using specific mechanisms of tolerance that are more efficient than in the halophytes, such as a less pronounced inhibition of photosynthesis, the accumulation of higher levels of Cl− ions in the leaves, or the activation of K+ uptake and transport to the aerial part under high salinity conditions.

Salt tolerance of the halophyte Limonium delicatulum is more associated with antioxidant enzyme activities than phenolic compounds

2016 ◽  
Vol 43 (7) ◽  
pp. 607 ◽  
Author(s):  
Souid Aymen ◽  
Gabriele Morena ◽  
Longo Vincenzo ◽  
Pucci Laura ◽  
Bellani Lorenza ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Photosynthetic Performance ◽  
Polyphenolic Compounds ◽  
Antioxidant Enzyme Activities ◽  
Strongly Correlated ◽  
Growth Responses ◽  
Antioxidant Responses ◽  
Stress Markers ◽  
Biochemical Assays ◽  
Nacl Concentration

In this work we studied the effect of salinity (ranging from 50 to 500 mM NaCl) on the physiological and the antioxidant responses of the local halophyte Limonium delicatulum Kuntze. We based our analysis on 12 biochemical assays that are commonly used to measure the antioxidant responses under stress such as oxidative stress markers, enzymes activities and polyphenolic compounds. Our aim was to study parameters that are strongly correlated with the growth response to salinity. Results showed two different growth responses depending on the concentration of NaCl in the medium. Under 50 to 200 mM, the growth was stimulated before it decreased significantly at 300–500 mM. L. delicatulum revealed a good aptitude to maintain photosynthetic machinery by increasing the concentrations of photosynthetic pigments, which is essential for the stabilisation of photosystems and the photosynthesis process under optimal NaCl concentration. Their breakdown at higher salinity decreased the photosynthetic performance of plants resulting in growth inhibition. Moreover, to reduce the damaging effect of oxidative stress and to tolerate the accumulation of salt ions, L. delicatulum induced the activities of their antioxidant enzymes more than their contents in polyphenolic compounds.

scholarly journals Sodium Chloride-Induced Salt Stress Responses of Antioxidative Activities in Leaves and Roots of Pistachio Rootstock

2019 ◽  
Author(s):  
Mohammad Akbari ◽  
Ramesh katam ◽  
Rabab Husain ◽  
Mostafa Farajpour ◽  
Silvia Mazzuca ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Enzymes ◽  
Salt Stress ◽  
Sodium Chloride ◽  
Salinity Tolerance ◽  
Stress Responses ◽  
Leaf Tissue ◽  
Crop Productivity ◽  
Salinity Treatment ◽  
Leaves And Roots

Salinity substantially affects plant growth and crop productivity worldwide. Plants adopt several biochemical mechanisms including regulation of antioxidant biosynthesis to protect themselves against the toxic effects induced by the stress. One-year-old Pistachio rootstock exhibiting different degrees of salinity tolerance were subjected to sodium chloride induced salt stress to identify genetic diversity among cultivated pistachio rootstock for their antioxidant responses, and to determine the correlation of these enzymes to salinity stress. Leaves and roots were harvested following NaCl-induced stress. Results show that a higher concentration of NaCl treatment induced oxidative stress in the leaf tissue and to a lesser extent in the roots. Both tissues showed an increase in ascorbate peroxidase, superoxide dismutase, catalase, glutathione reductase, peroxidase and malondialdehyde. Responses of antioxidant enzymes were cultivar dependent, as well as temporal and dependent on the salinity level. Linear and quadratic regression model analysis revealed significant correlation of enzyme activities to salinity treatment in both tissues. The variation in salinity tolerance reflected their capabilities in orchestrating antioxidant enzymes at the roots and harmonized across the cell membranes of the leaves. The study provides a better understanding of root and leaf coordination in regulating the antioxidant enzymes to NaCl induced oxidative stress.

scholarly journals Role of Silicon in Mediating Salt Tolerance in Plants: A Review

Plants ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 147 ◽  
Author(s):  
Yong-Xing Zhu ◽  
Hai-Jun Gong ◽  
Jun-Liang Yin
Keyword(s):  
Oxidative Stress ◽  
Salt Stress ◽  
Osmotic Stress ◽  
Stress Responses ◽  
Polyamine Metabolism ◽  
Research Areas ◽  
Aquaporin Gene ◽  
Ion Imbalance ◽  
The Impact

Salt stress is a major threat for plant growth worldwide. The regulatory mechanisms of silicon in alleviating salt stress have been widely studied using physiological, molecular genetics, and genomic approaches. Recently, progresses have been made in elucidating the alleviative effects of silicon in salt-induced osmotic stress, Na toxicity, and oxidative stress. In this review, we highlight recent development on the impact of silicon application on salt stress responses. Emphasis will be given to the following aspects. (1) Silicon transporters have been experimentally identified in different plant species and their structure feature could be an important molecular basis for silicon permeability. (2) Silicon could mediate salt-induced ion imbalance by (i) regulating Na+ uptake, transport, and distribution and (ii) regulating polyamine levels. (3) Si-mediated upregulation of aquaporin gene expression and osmotic adjustment play important roles in alleviating salinity-induced osmotic stress. (4) Silicon application direct/indirectly mitigates oxidative stress via regulating the antioxidant defense and polyamine metabolism. (5) Omics studies reveal that silicon could regulate plants’ response to salt stress by modulating the expression of various genes including transcription factors and hormone-related genes. Finally, research areas that require further investigation to provide a deeper understanding of the role of silicon in plants are highlighted.

scholarly journals Growth, Physiological and Biochemical Responses of two Greek Cotton Cultivars to Salt Stress and their Impact as Selection Indices for Salt Tolerance

2019 ◽  
Vol 47 (3) ◽  
Author(s):  
Maria-Anna MOUSSOURAKI ◽  
Eleni TANI ◽  
Anna VELLIOU ◽  
Maria GOUFA ◽  
Maria PSYCHOGIOU ◽  
...  
Keyword(s):  
Salt Stress ◽  
Gas Exchange ◽  
Stress Responses ◽  
Ion Homeostasis ◽  
Membrane Integrity ◽  
Dry Weight ◽  
Agricultural Product ◽  
Digital Object Identifier ◽  
Sensitivity Index ◽  
Nacl Concentration

Soil salinity is a major constrain of crop productivity. Upland cotton (Gossypium hirsutum L.) is an important fiber crop worldwide and a major agricultural product in Greece. Two commercial cotton cultivars (‘Hersi’ and ‘ST 318’) were studied to compare their response under non-saline and saline conditions in a greenhouse experiment. Salt stress on plants was imposed by two different approaches: a gradual and an initial acclimatization to a non-lethal NaCl concentration (150 mM). To explore salt stress responses, growth (height of plants, roots, shoots and leaves dry weight, reproductive shoots, Salinity Sensitivity Index), gas exchange (Photosynthetic rate, Stomatal conductance, Transpiration rate and Water Use Efficiency) and biochemical parameters (proline, H2O2 and MDA content), were examined as well as ion homeostasis. ‘Hersi’ had significantly higher dry weight of roots, shoots and leaves, lower salinity sensitivity index of roots compared to ‘ST 318’.  In this regard, it appears that ‘Hersi’ cultivar performed better than ‘ST 318’ to increased salinity conditions, due to better control of gas exchange parameters and K+/Na+ homeostasis as well as better membrane integrity. Furthermore, the gradual acclimatization to the 150 mM NaCl concentration had a milder effect on both cultivars compared to the initial acclimatization.   ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 3, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********

scholarly journals Investigation of an Antioxidative System for Salinity Tolerance in Oenanthe javanica

Antioxidants ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 940
Author(s):  
Sunjeet Kumar ◽  
Gaojie Li ◽  
Jingjing Yang ◽  
Xinfang Huang ◽  
Qun Ji ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Enzymes ◽  
Salt Stress ◽  
Stress Responses ◽  
Defense Mechanism ◽  
Crop Improvement ◽  
Antioxidant Defense System ◽  
Growth And Yield ◽  
Oenanthe Javanica ◽  
Water Dropwort

Abiotic stress, such as drought and salinity, severely affect the growth and yield of many plants. Oenanthe javanica (commonly known as water dropwort) is an important vegetable that is grown in the saline-alkali soils of East Asia, where salinity is the limiting environmental factor. To study the defense mechanism of salt stress responses in water dropwort, we studied two water dropwort cultivars, V11E0022 and V11E0135, based on phenotypic and physiological indexes. We found that V11E0022 were tolerant to salt stress, as a result of good antioxidant defense system in the form of osmolyte (proline), antioxidants (polyphenols and flavonoids), and antioxidant enzymes (APX and CAT), which provided novel insights for salt-tolerant mechanisms. Then, a comparative transcriptomic analysis was conducted, and Gene Ontology (GO) analysis revealed that differentially expressed genes (DEGs) involved in the carbohydrate metabolic process could reduce oxidative stress and enhance energy production that can help in adaptation against salt stress. Similarly, lipid metabolic processes can also enhance tolerance against salt stress by reducing the transpiration rate, H2O2, and oxidative stress. Furthermore, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that DEGs involved in hormone signals transduction pathway promoted the activities of antioxidant enzymes and reduced oxidative stress; likewise, arginine and proline metabolism, and flavonoid pathways also stimulated the biosynthesis of proline and flavonoids, respectively, in response to salt stress. Moreover, transcription factors (TFs) were also identified, which play an important role in salt stress tolerance of water dropwort. The finding of this study will be helpful for crop improvement under salt stress.

scholarly journals GmNAC06, a NAC domain transcription factor enhances salt stress tolerance in soybean

2020 ◽  
Author(s):  
Ming Li ◽  
Rui Chen ◽  
Qiyan Jiang ◽  
Xianjun Sun ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Salt Stress ◽  
Hairy Roots ◽  
Stress Responses ◽  
High Salinity ◽  
Negative Effects ◽  
Ionic Homeostasis ◽  
Transgenic Hairy Roots ◽  
Localization Analysis ◽  
Soybean Plants

Key message We found GmNAC06 plays an important role in salt stress responses through the phenotypic, physiological and molecular analyses of OE, VC, and Mutant composite soybean. Abstract Salinization affects 20% of all cultivated land worldwide because of the high salinity of irrigation water and the excessive use of water, and this amount is increasing daily. NAC (NAM, ATAF, and CUC) have been found to be involved in salt stress. In this study, a soybean NAC gene, GmNAC06 (Glyma06g21020.1), was cloned and functionally characterized. The results of expression analysis suggested that salt stress could influence the expression level of GmNAC06. The subcellular localization analysis results suggested that GmNAC06 may function as a transcription factor. Under salt stress, the overexpression technology combined with CRISPR-Cas9 system found that GmNAC06 could cause the accumulation of proline and glycine betaine to alleviate or avoid the negative effects of ROS; similarly, it could control the Na+/K+ ratios in hairy roots to maintain ionic homeostasis. The fresh weight of the transgenic hairy roots and the histochemical ROS staining of wild leaves suggested that transgenic hairy roots influence the function of wild leaves under salt stress conditions. Moreover, the expression levels of GmUBC2 and GmHKT1 were higher in the GmNAC06 hairy roots than in the control. Thus, the overexpression of GmNAC06 in hairy roots notably causes an entire composite plant to exhibit salt tolerance. The phenotype of composite soybean plants and transgenic Arabidopsis plants suggest that GmNAC06 plays a role in response to salt stress and could be useful in generating salt tolerant transgenic crops.

scholarly journals Responses to Salt Stress in Portulaca: Insight into Its Tolerance Mechanisms

Plants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1660
Author(s):  
Orsolya Borsai ◽  
Mohamad Al Hassan ◽  
Cornel Negrușier ◽  
M. Dolores Raigón ◽  
Monica Boscaiu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Salt Stress ◽  
Photosynthetic Pigments ◽  
Growth Parameters ◽  
Soluble Sugars ◽  
Total Phenolic ◽  
Saline Stress ◽  
Enzymatic Antioxidants ◽  
Stress Markers ◽  
Monovalent Ions

Climate change and its detrimental effects on agricultural production, freshwater availability and biodiversity accentuated the need for more stress-tolerant varieties of crops. This requires unraveling the underlying pathways that convey tolerance to abiotic stress in wild relatives of food crops, industrial crops and ornamentals, whose tolerance was not eroded by crop cycles. In this work we try to demonstrate the feasibility of such strategy applying and investigating the effects of saline stress in different species and cultivars of Portulaca. We attempted to unravel the main mechanisms of stress tolerance in this genus and to identify genotypes with higher tolerance, a procedure that could be used as an early detection method for other ornamental and minor crops. To investigate these mechanisms, six-week-old seedlings were subjected to saline stress for 5 weeks with increasing salt concentrations (up to 400 mM NaCl). Several growth parameters and biochemical stress markers were determined in treated and control plants, such as photosynthetic pigments, monovalent ions (Na+, K+ and Cl−), different osmolytes (proline and soluble sugars), oxidative stress markers (malondialdehyde—a by-product of membrane lipid peroxidation—MDA) and non-enzymatic antioxidants (total phenolic compounds and total flavonoids). The applied salt stress inhibited plant growth, degraded photosynthetic pigments, increased concentrations of specific osmolytes in both leaves and roots, but did not induce significant oxidative stress, as demonstrated by only small fluctuations in MDA levels. All Portulaca genotypes analyzed were found to be Na+ and Cl− includers, accumulating high amounts of these ions under saline stress conditions, but P. grandiflora proved to be more salt tolerant, showing only a small reduction under growth stress, an increased flower production and the lowest reduction in K+/Na+ rate in its leaves.

scholarly journals Kinetics of the antioxidant response to salinity in the halophyte Limonium bicolour

2008 ◽  
Vol 54 (No. 11) ◽  
pp. 493-497 ◽  
Author(s):  
Y. Li
Keyword(s):  
Oxidative Stress ◽  
Superoxide Dismutase ◽  
Salt Stress ◽  
Dry Weight ◽  
Antioxidant Response ◽  
Fresh Weight ◽  
Nacl Concentration ◽  
Anti Oxidant ◽  
Low Levels ◽  
Kinetics Of

The fresh weight (fw) and dry weight (dw) of shoots and roots, the activity of anti-oxidant enzymes [superoxide dismutase (SOD), peroxidase (POD), catalase (CAT)], and parameters of oxidative stress of shoots – malondialdehyde (MDA) – were investigated in <I>Limonium bicolor</I>, a naturally salt-resistant halophyte. The seedlings of <I>L. bicolour</I> were treated with different (0, 100, 200, 400 mmol/l) NaCl concentrations. The results showed that NaCl played an important role in growth of <I>L. bicolour</I>. It made obviously promotion of a certain NaCl concentration to growth of <I>L. bicolor</I>, the seedlings of <I>L. bicolour</I> grew best under 100 mmol/l salt concentration, fresh weight and dry weight reached the maximum. MDA concentration of shoots slightly decreased under 100 mmol/l salt stress, then increased with increased NaCl concentration. The activities of SOD, POD and CAT increased with the increase of the concentration of NaCl in shoots of <I>L. bicolour</I>. The salt tolerance of this halophyte under salt stress conditions is probably due to its ability to exhibit high SOD, POD and CAT enzyme activities and low levels of oxidative stress.

scholarly journals Multidisciplinary studies supporting conservation programmes of two rare, endangered Limonium species from Spain

2021 ◽  
Author(s):  
Sara González-Orenga ◽  
Ma Pilar Donat-Torres ◽  
Josep V. Llinares ◽  
Albert Navarro ◽  
Francisco Collado ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Enzymes ◽  
Salt Stress ◽  
Water Stress ◽  
Stress Responses ◽  
Salt Marshes ◽  
Severe Drought ◽  
Natural Habitats ◽  
Controlled Conditions ◽  
Number Of Individuals

Abstract Background and aims Two local threatened endemics from Valencian salt marshes were analysed from a multidisciplinary perspective combining field studies with experiments performed under greenhouse-controlled conditions. The work aimed to investigate the habitat of the two species but also to explore their limits of tolerance to severe drought and salinity and the mechanisms behind their stress responses. Methods The number of individuals in several populations, climatic conditions, soil characteristics and accompanying vegetation in the natural habitats were analysed in the field study. Plants obtained by seed germination were grown in the greenhouse and subjected to one month of water and salt stress treatments. Growth and biochemical parameters were analysed after the treatments were finalised. Results No correlation between climatic parameters and the number of individuals censed of the two Limonium species could be established. Although L. dufourii was found in more saline soils in the natural habitats, under controlled greenhouse conditions, this species was more severely affected by salt treatment than L. albuferae, which is more susceptible to water stress. A common biochemical response was the increase of proline under all stress treatments, but mostly in water-stressed plants. Oxidative stress markers, MDA and H2O2, did not indicate significant differences between the treatments. The differences in the two species' responses to the two kinds of stress were correlated with the activation of the antioxidant enzymes, more pronounced in conditions of salt stress in L. albuferae and of water stress in L. dufourii. Conclusions Although L. albuferae is found in sites with lower salinity in the natural habitats, the greenhouse experiment indicated that it tolerates higher concentrations of salt than L. dufouri, which is more resistant to drought. The two species efficiently mitigate oxidative stress by activation of antioxidant enzymes. The results obtained may be helpful for the conservation management of the two species: whereas salinity is not problematic, as the two species tolerated under controlled conditions salinities far beyond those in their natural environments, water scarcity may be a problem for L. albuferae, which proved to be more susceptible to water deficit.

Sign in / Sign up

Export Citation Format

Share Document