Differential response of salt stress on Brassica juncea: Photosynthetic performance, pigment, proline, D1 and antioxidant enzymes

Abstract The involvement of ethylene in reversal of salt stress inhibited photosynthetic activity and growth by salicylic acid (SA) together with sulfur (S) was studied in mustard (Brassica juncea L.) plants. Application of SA (0.5 mM) plus SO42- (2.0 mM) improved photosynthetic activity through markedly increased S-assimilation, antioxidant enzymes activity and optimized ethylene and glutathione (GSH) production for reduced reactive oxygen species (ROS) in plants under 50 mM NaCl stress. As SA acts as an inhibitor of ethylene, and S-assimilation is associated with ethylene synthesis, we tried to figure out the interaction of ethylene in SA and SO42- mediated salt tolerance. The involvement of ethylene was studied by supplementing salt treated plants with 200 µL L-1 ethephon (an ethylene-releasing compound) or 100 µM norbornadiene (NBD, ethylene action inhibitor) to SA and SO42- treatments. The ethephon application to salt treated plants suppressed stress ethylene and optimized ethylene formation and increased ethylene sensitivity to enhance photosynthesis of plants by affecting antioxidative capacity of plants. Application of NBD to plants receiving SA plus SO42- in presence of salt showed inhibited photosynthetic characteristics, stomatal behavior and growth. These plants exhibited minimal capacity of S-assimilation and antioxidant enzymes activity and GSH content. This explained that ethylene was involved in the reversal of salt stress by SA plus SO42-. Thus, the study showed that ethylene intervenes the effect of SA in the presence of SO42- to upregulate the antioxidants that lead to increased S-assimilation, and imparted tolerance to salt in mustard plants.

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Ethylene Supplementation Combined with Split Application of Nitrogen and Sulfur Protects Salt-Inhibited Photosynthesis through Optimization of Proline Metabolism and Antioxidant System in Mustard (Brassica juncea L.)

Plants ◽

10.3390/plants10071303 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1303

Author(s):

Badar Jahan ◽

Noushina Iqbal ◽

Mehar Fatma ◽

Zebus Sehar ◽

Asim Masood ◽

...

Keyword(s):

Salt Stress ◽

Brassica Juncea ◽

Antioxidant System ◽

Photosynthetic Efficiency ◽

Growth Potential ◽

Proline Metabolism ◽

Sowing Time ◽

Stress Effects ◽

Nutrient Assimilation ◽

S Application

In the present study, the potential of ethylene as ethephon (an ethylene source) was investigated individually and in combination with split doses of nitrogen (N) and sulfur (S) soil treatments for removal of the damaging effects of salt stress (100 mM NaCl) in mustard (Brassica juncea L.). Plants were grown with 50 mg N plus 50 mg S kg−1 soil at sowing time and an equivalent dose at 20 days after sowing [N50 + S50]0d and 20d. Ethephon at 200 μL L‒1 was applied to combined split doses of N and S with or without NaCl. Plants subjected to NaCl showed a decrease in growth and photosynthetic characteristics as well as N and S assimilation, whereas proline metabolism and antioxidants increased. The application of ethephon to plants grown with split N and S doses significantly enhanced photosynthetic efficiency by increasing the assimilation of N and S, improving the concentration of proline and induction of the antioxidant system with or without NaCl. The regulation of ethylene and/or split forms of N and S application may be potential tools for not just overcoming salt stress effects in this species and in related Brassicaceae but also enhancing their photosynthesis and growth potential through increased nutrient assimilation.

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Moderate Boron Concentration Beneficial for Flue-cured Tobacco Seedlings Growth and Development

10.21203/rs.3.rs-489172/v1 ◽

2021 ◽

Author(s):

Mengxia Li ◽

Xiaopeng Deng ◽

Ke Ren ◽

Rui Liu ◽

Tao Wang ◽

...

Keyword(s):

Antioxidant Enzymes ◽

Dry Matter ◽

Agronomic Traits ◽

Photosynthetic Performance ◽

Leaf Length ◽

Internal Quality ◽

Root Weight ◽

Nicotine Content ◽

Hydroponic Experiment ◽

Tobacco Seedlings

Abstract Boron (B) is a micronutrient tobacco needs in minute amounts, and Boron insufficient supply can causes significant tobacco yield loss, however, the appropriate concentration for flue-cured tobacco seedlings to growth remains unknown. In this sense, a hydroponic experiment was conduct to measure the agronomic traits, dry matter mass, chlorophyll content, photosynthetic performance, antioxidant enzymes, boron ion and nicotine content of flue-cured tobacco seedlings K326 under different boron concentrations of 0.000mmol/L (B1, CK), 0.125mmol/L (B2), 0.250mmol/L (B3), 0.750mmol/L (B4), 5.000mmol/L (B5), 10.000mmol/L (B6), 20.000mmol/L (B7), 40.000mmol/L (B8) after 30 days. B significantly influenced flue-tobacco seedlings growth on agronomic traits, photosynthetic performance, the activities of antioxidant enzymes, boron ion and nicotine content aspects. B linearly enhanced the accumulation of boron ion by 24.00%~96.44%, and decreased nicotine content by 21.60%~82.03% in tobacco seedlings. Solution B concentration at 0.750 and 5.000mmol/L markedly improved tobacco seedlings maximum leaf length by 4.83%~82.03% and leaf width by 0.77%~24.36%, root weight by 13.64%~56.82%, stem weight by 12.26%~52.36%, leaf weight by 9.68%~36.56%, dry matter mass by 10.65%~38.92%, the Pn parameter by 1.22%~80.28%, the Cond paramete by 33.40%~75.86%, while decreased the activities of SOD by 10.44%~91.67%, POD by 21.32%~65.62% and CAT by 50.05%~96.44%, and MDA by 16.23%~75.16%. The B concentration concluded in this study enhanced the agronomy traits, photosynthetic and biochemical characteristics of flue-cured tobacco seedlings, which lays a scientific theoretical foundation for rational application of B in tobacco production and improve the internal quality of flue-cured tobacco.

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Proline and Proline Metabolising Enzymes in in-vitro Selected NaCl-tolerant Brassica juncea L. under Salt Stress

Annals of Botany ◽

10.1006/anbo.1995.1077 ◽

1995 ◽

Vol 76 (1) ◽

pp. 51-57 ◽

Cited By ~ 85

Author(s):

S Madan

Keyword(s):

Salt Stress ◽

Brassica Juncea

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Differential response of arsenic stress in two varieties of Brassica juncea L.

Chemosphere ◽

10.1016/j.chemosphere.2008.11.023 ◽

2009 ◽

Vol 74 (9) ◽

pp. 1201-1208 ◽

Cited By ~ 98

Author(s):

Meetu Gupta ◽

Pallavi Sharma ◽

Neera Bhalla Sarin ◽

Alok Krishna Sinha

Keyword(s):

Brassica Juncea ◽

Differential Response ◽

Arsenic Stress

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Variations in leaf gas exchange, chlorophyll fluorescence and membrane potential of Medicago sativa root cortex cells exposed to increased salinity: The role of the antioxidant potential in salt tolerance

Archives of Biological Sciences ◽

10.2298/abs171019001f ◽

2018 ◽

Vol 70 (3) ◽

pp. 413-423 ◽

Cited By ~ 2

Author(s):

Mohamed Farissi ◽

Mohammed Mouradi ◽

Omar Farssi ◽

Abdelaziz Bouizgaren ◽

Cherki Ghoulam

Keyword(s):

Antioxidant Enzymes ◽

Salt Stress ◽

Chlorophyll Fluorescence ◽

Membrane Potential ◽

Salt Tolerance ◽

Gas Exchange ◽

Medicago Sativa ◽

Leaf Gas Exchange ◽

Root Cortex ◽

Root Cortex Cells

Salinity is one of the most serious agricultural problems that adversely affects growth and productivity of pasture crops such as alfalfa. In this study, the effects of salinity on some ecophysiological and biochemical criteria associated with salt tolerance were assessed in two Moroccan alfalfa (Medicago sativa L.) populations, Taf 1 and Tata. The experiment was conducted in a hydro-aeroponic system containing nutrient solutions, with the addition of NaCl at concentrations of 100 and 200 mM. The salt stress was applied for a month. Several traits in relation to salt tolerance, such as plant dry biomass, relative water content, leaf gas exchange, chlorophyll fluorescence, nutrient uptake, lipid peroxidation and antioxidant enzymes, were analyzed at the end of the experiment. The membrane potential was measured in root cortex cells of plants grown with or without NaCl treatment during a week. The results indicated that under salt stress, plant growth and all of the studied physiological and biochemical traits were significantly decreased, except for malondialdehyde and H2O2 contents, which were found to be increased under salt stress. Depolarization of membrane root cortex cells with the increase in external NaCl concentration was noted, irrespective of the growth conditions. The Tata population was more tolerant to high salinity (200 mM NaCl) and its tolerance was associated with the ability of plants to maintain adequate levels of the studied parameters and their ability to overcome oxidative stress by the induction of antioxidant enzymes, such as guaiacol peroxidase, catalase and superoxide dismutase.

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Differential Response to Sea Salt Salinity by Nitrate and Antioxidant System in Six Soybean Varieties

Cercetari Agronomice in Moldova ◽

10.1515/cerce-2015-0051 ◽

2015 ◽

Vol 48 (4) ◽

pp. 39-50 ◽

Cited By ~ 1

Author(s):

K.M. Saad-Allah

Keyword(s):

Salt Stress ◽

Antioxidant System ◽

Salt Concentration ◽

Nitrate Uptake ◽

Adaptive Strategy ◽

Differential Response ◽

Sea Salt ◽

Negative Consequences ◽

Gradual Decline ◽

Glycine Max L

AbstractSix varieties of soybean (Glycine max L.) plants were grown for 30 days under three levels of sea salt salinity (0.0, 8.0 and 16.0 mS/cm2) for studying the effect of sea salt on uptake of nitrate and response of the antioxidant system for these salinity doses. Salt treatments resulted in a gradual decline in nitrate uptake by increasing sea salt concentration, which mean that this will bring negative consequences on nitrogen assimilation. However, salt treatments induced the accumulation of hydrogen peroxide and glycinebetaine in the leaves of all soybean verities as an adaptive strategy to cope with salt stress. On the other hand, there was a differential response in phenolic compounds among soybean verities as a function of salt concentration and the studied variety, which means there has a decline in phenolics under salt stress in the varieties Crawford, G21, G22 and G83, but in contrary in G35 and G82, phenolics has accumulated in response to salinity. Isozymes electrophoretic banding showed changes in peroxidase activity with sea salt, however superoxide dismutase showed stability in number and intensity of bands with salt treatments. Esterase enzyme was more sensitive to salinity and showed a gradual decline in activity by increasing salt concentration.

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