Integrated Application of Selenium and Silicon Enhances Growth and Anatomical Structure, Antioxidant Defense System and Yield of Wheat Grown in Salt-Stressed Soil

Selenium (Se) and silicon (Si) are considered advantageous elements to induce plants’ tolerance to various environmental stresses. Wheat yield is negatively affected by salinity stress, especially in dry and semi-dry areas. Therefore, the objective of the current study was to investigate the effects of Se, Si and their combinations (0 as control, Se15, Se30, Si15, Si30, Se15 + Si15, and Se30 + Si30 mM) in alleviating the deleterious effects of salinity stress (7.61 dS m−1, real field conditions) on anatomical characteristics as well as the physio-biochemical and productivity parameters of wheat plants. The selenium and silicon treatments and their combinations caused significant amelioration in growth, anatomical and physiological attributes, and grain yields of salinity-stressed wheat in comparison with the untreated plants (control treatment). The integrated application of Se30 + Si30 significantly increased plant growth (i.e., plant height 28.24%, number of tillers m−2 76.81%, fresh weight plant−1 80.66%, and dry weight plant−1 79.65%), Fv/Fm (44.78%), performance index (PI; 60.45%), membrane stability index (MSI; 36.39%), relative water content (RWC; 29.39%), total soluble sugars (TSS; 53.38%), proline (33.74%), enzymatic antioxidants (i.e., CAT activity by 14.45%, GR activity by 67.5%, SOD activity by 35.37% and APX activity by 39.25%) and non-enzymatic antioxidants (i.e., GSH content by 117.5%, AsA content by 52.32%), yield and its components (i.e., number of spikelets spike−1 29.55%, 1000-grain weight 48.73% and grain yield ha−1 26.44%). The anatomical traits of stem and leaves were improved in wheat plants treated with Se30 + Si30. These changes resulting from the exogenous applications of Se, Si or their combinations, in turn, make these elements prospective in helping wheat plants to acclimate successfully to saline soil.

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Assessment of Morpho-Physiological, Biochemical and Antioxidant Responses of Tomato Landraces to Salinity Stress

Plants ◽

10.3390/plants10040696 ◽

2021 ◽

Vol 10 (4) ◽

pp. 696

Author(s):

Reem H. Alzahib ◽

Hussein M. Migdadi ◽

Abdullah A. Al Ghamdi ◽

Mona S. Alwahibi ◽

Abdullah A. Ibrahim ◽

...

Keyword(s):

Salt Stress ◽

Salinity Stress ◽

Dry Weight ◽

Proline Content ◽

Enzymatic Antioxidants ◽

Sod Activity ◽

Carotene Content ◽

Antioxidants Activity ◽

Solanum Lycopersicum L ◽

Salinity Levels

Understanding salt tolerance in tomato (Solanum lycopersicum L.) landraces will facilitate their use in genetic improvement. The study assessed the morpho-physiological variability of Hail tomato landraces in response to different salinity levels at seedling stages and recommended a tomato salt-tolerant landrace for future breeding programs. Three tomato landraces, Hail 548, Hail 747, and Hail 1072 were tested under three salinity levels: 75, 150, and 300 mM NaCl. Salinity stress reduced shoots’ fresh and dry weight by 71% and 72%, and roots were 86.5% and 78.6%, respectively. There was 22% reduced chlorophyll content, carotene content by 18.6%, and anthocyanin by 41.1%. Proline content increased for stressed treatments. The 300 mM NaCl treatment recorded the most proline content increases (67.37 mg/g fresh weight), with a percent increase in proline reaching 61.67% in Hail 747. Superoxide dismutase (SOD) activity decreased by 65% in Hail 548, while it relatively increased in Hail 747 and Hail 1072 treated with 300 mM NaCl. Catalase (CAT) activity was enhanced by salt stress in Hail 548 and recorded 7.6%, increasing at 75 and 5.1% at 300 mM NaCl. It revealed a reduction in malondialdehyde (MDA) at the 300 mM NaCl concentration in both Hail 548 and Hail 1072 landraces. Increasing salt concentrations showed a reduction in transpiration rate of 70.55%, 7.13% in stomatal conductance, and 72.34% in photosynthetic rate. K+/Na+ ratios decreased from 56% for 75 mM NaCl to 85% for 300 mM NaCl treatments in all genotypes. The response to salt stress in landraces involved some modifications in morphology, physiology, and metabolism. The landrace Hail 548 may have better protection against salt stress and observed protection against reactive oxygen species (ROS) by increasing enzymatic “antioxidants” activity under salt stress.

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Physiological and Biochemical Mechanisms of Exogenously Applied Selenium for Alleviating Destructive Impacts Induced by Salinity Stress in Bread Wheat

Agronomy ◽

10.3390/agronomy11050926 ◽

2021 ◽

Vol 11 (5) ◽

pp. 926

Author(s):

El-Sayed M. Desoky ◽

Abdel-Rahman M. A. Merwad ◽

Mohamed F. Abo El-Maati ◽

Elsayed Mansour ◽

Safaa M. A. I. Arnaout ◽

...

Keyword(s):

Bread Wheat ◽

Salinity Stress ◽

Foliar Application ◽

Soluble Sugars ◽

Wheat Yield ◽

Stability Index ◽

Antioxidant Compounds ◽

Antioxidant Enzyme Activities ◽

Yield Attributes ◽

Antioxidant Defense Systems

Salinity is a major abiotic stress that poses great obstacles to wheat production, especially in arid regions. The application of exogenous substances can enhance plant salt tolerance and increase its productivity under salinity stress. This work aimed to assess the mechanisms of selenium (Se) at different concentrations (2, 4 and 8 μM SeCl2) to mitigate hazardous impacts of salt toxicity at physiological, biochemical and agronomic levels in bread wheat. The results displayed that Se foliar application increased chlorophyll content, net photosynthetic rate, transpiration rate, stomatal conductance, relative water content, membrane stability index, excised leaf water retention, proline, total soluble sugars, Ca content, K content, antioxidant enzyme activities and non-enzymatic antioxidant compounds compared to untreated plants. On the other hand, Se application decreased the content of Na, hydrogen peroxide and superoxide contents. Accordingly, our findings recommend exogenous Se application (in particular 8 μM) to alleviate the deleterious effects induced by salinity stress and improve wheat yield attributes through enhancing antioxidant defense systems and photosynthetic capacity.

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Aqueous Garlic Extract as a Plant Biostimulant Enhances Physiology, Improves Crop Quality and Metabolite Abundance, and Primes the Defense Responses of Receiver Plants

Applied Sciences ◽

10.3390/app8091505 ◽

2018 ◽

Vol 8 (9) ◽

pp. 1505 ◽

Cited By ~ 8

Author(s):

Sikandar Hayat ◽

Husain Ahmad ◽

Muhammad Ali ◽

Kashif Hayat ◽

Muhammad Khan ◽

...

Keyword(s):

Foliar Application ◽

Fungal Infections ◽

Soluble Sugars ◽

Dry Weight ◽

Defense Responses ◽

Garlic Extract ◽

Control Treatment ◽

Antioxidant Systems ◽

Plant Metabolites ◽

Crop Quality

Biostimulants are the next-generation choice for sustainable agricultural production and are gradually becoming an alternative to synthetic chemicals. Various botanicals are proposed to exert stimulatory effects, and garlic allelochemicals are among such botanicals; however, a peer-reviewed scientific evaluation is required to understand garlic-derived substances such as biostimulants. Current studies were therefore performed to identify the bioactivity of garlic extract as a biostimulant to improve crop quality, alter its physiological potential, and prime its defense responses against pathogenic fungal infections. 100 µg mL−1 aqueous garlic extracts (AGE) in consort with 1 mM of acetyl salicylic acid (ASA) and distilled water as a control treatment were applied to eggplant and pepper seedlings as foliar application and fertigation methods. The results revealed stimulatory responses in the growth of the vegetables with improved plant height, number of leaves, root growth, fresh and dry weight, etc., due to AGE and ASA applications. Moreover, significant alterations were indicated in plant metabolites such as chlorophyll, carotenoids, and soluble sugars. Additionally, stimulation of the antioxidant enzymes such as superoxide dismutase (SOD) and peroxidase (POD), as well as the root activity of these plants, was observed after treatment. Application of AGE and ASA also exerted priming effects on pepper plants, inducing defense responses prior to Phytopthora capsici inoculation, and the treated plants therefore successfully resisted infection through activated antioxidant systems, and probably carotenoid and other protectory metabolites. Stress-induced H2O2 content was extremely low in the treated plants, indicating successful resistance against pathogenic infection.

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Positive Salt Tolerance Modulation via Vermicompost Regulation of SOS1 Gene Expression and Antioxidant Homeostasis in Viciafaba Plant

Plants ◽

10.3390/plants10112477 ◽

2021 ◽

Vol 10 (11) ◽

pp. 2477

Author(s):

Rehab El-Dakak ◽

Weam El-Aggan ◽

Ghadah Badr ◽

Amira Helaly ◽

Amel Tammam

Keyword(s):

Gene Expression ◽

Salinity Stress ◽

Broad Bean ◽

Dry Weight ◽

Dual Function ◽

Enzymatic Antioxidants ◽

Randomized Design ◽

Strategic Implementation ◽

Salt Overly Sensitive

Strategic implementation of vermicompost as safe biofertilizer besides defensing saline soils offer dual function solving problems in developing countries. The current study aims to utilize vermicompost (VC) for amelioration of 200mM NaCl in Vicia faba Aspani cultivar and investigate the molecular role of salt overly sensitive pathway (SOS1). The experiment was conducted following a completely randomized design with three replicates. Treatments include 0; 2.5; 5; 10; 15% dried VC intermingled with soil mixture (clay: sand; 1:2) and/or 200 mM NaCl. The results show that salinity stress decreased broad bean fresh and dry weight; and K+/Na+. However, malonedialdehyde and H2O2 contents; increased. Application of 10% VC and salinity stress increases Ca2+ (41% and 50%), K+/Na+ (125% and 89%), Mg2+ (25% and 36%), N (8% and 11%), indole acetic acid (70% and 152%) and proteins (9% and 13%) for root and shoot, respectively, in comparison to salt treated pots. Moreover, all examined enzymatic antioxidants and their substrates increased, except glutathione reductase. A parallel decrease in abscisic acid (75% and 29%) and proline (59% and 58%) was also recorded for roots and leaves, respectively. Interestingly, the highly significant increase in gene expression of SOS1 (45-fold) could drive defense machinery of broad bean to counteract 200 mM NaCl.

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Regulation of Agronomic Traits, Nutrient Uptake, Osmolytes and Antioxidants of Maize as Influenced by Exogenous Potassium Silicate under Deficit Irrigation and Semiarid Conditions

Agronomy ◽

10.3390/agronomy10081212 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1212 ◽

Cited By ~ 2

Author(s):

Mohamed F. M. Ibrahim ◽

Gomaa Abd El-Samad ◽

Hatem Ashour ◽

Ahmed M. El-Sawy ◽

Mohamed Hikal ◽

...

Keyword(s):

Grain Yield ◽

Deficit Irrigation ◽

Soluble Sugars ◽

Dry Weight ◽

Potassium Silicate ◽

Enzymatic Antioxidants ◽

Area Index ◽

Close Link ◽

Maize Plants ◽

Semiarid Conditions

Understanding the link between the protective role of potassium silicate (K2SiO3) against water shortage and the eventual grain yield of maize plants is still limited under semiarid conditions. Therefore, in this study, we provide insights into the underlying metabolic responses, mineral nutrients uptake and some nonenzymatic and enzymatic antioxidants that may differ in maize plants as influenced by the foliar application of K2SiO3 (0, 1 and 2 mM) under three drip irrigation regimes (100, 75 and 50% of water requirements). Our results indicated that, generally, plants were affected by both moderate and severe deficit irrigation levels. Deficit irrigation decreased shoot dry weight, root dry weight, leaf area index (LAI), relative water content (RWC), N, P, K, Ca, Fe, Zn, carotenoids, grain yield and its parameters, while root/shoot ratio, malondialdehyde (MDA), proline, soluble sugars, ascorbic acid, soluble phenols, peroxidase (POD), catalase (CAT), polyphenol oxidase (PPO), and ascorbate peroxidase (APX) were improved. The foliar applications of K2SiO3 relatively alleviated water stress-induced damage. In this respect, the treatment of 2 mM K2SiO3 was more effective than others and could be recommended to mitigate the effect of deficit irrigation on maize plants. Moreover, correlation analysis revealed a close link between yield and the most studied traits.

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Germination response of grasspea (Lathyrus sativus L.) and arugula (Eruca sativa L.) to osmotic and salinity stresses

Plant Breeding and Seed Science ◽

10.1515/plass-2015-0025 ◽

2015 ◽

Vol 71 (1) ◽

pp. 97-108 ◽

Cited By ~ 5

Author(s):

Hamid-Reza Fallahi ◽

Golsoom Fadaeian ◽

Marziyeh Gholami ◽

Omolbanin Daneshkhah ◽

Fatemeh Sadat Hosseini ◽

...

Keyword(s):

Osmotic Stress ◽

Salinity Stress ◽

Germination Rate ◽

Dry Weight ◽

Germination Percentage ◽

Control Treatment ◽

Breeding Programs ◽

Lathyrus Sativus L ◽

Germination Indices ◽

Different Levels

Abstract The use of genetic potential of forgotten plants such as grasspea and arugula is an appropriate strategy for increasing of plants tolerance to environmental stresses. Therefore, in this laboratory study the effects of different levels of osmotic (0, -2, -4, -6, -8, -10, -12 and -14 bar caused by PEG) and salinity (0, 50, 100, 150, 200, 250, 300 and 350 mmol induced by NaCl) stresses were evaluated on germination indices of grasspea and arugula in four separate experiments. Arugula showed a suitable tolerance to osmotic stress, so that its germination percentage and rate at treatment of -10 bar were similar to control. Arugula had 79% germination at osmotic level of -14 bar, but its germination rate at this level was 60% lower than control. In addition, its radicle length until -8 bar and radicle dry weight up to -14 bar were higher than control treatment. However, all levels of salinity stress particularly treatments of more than 100-150 mmol decreased the germination indices of arugula. Germination percentage of arugula in 150 and 200 mmol treatments was 22 and 56% lower than control treatment, respectively. Grasspea had partially suitable tolerance to osmotic stress until -6 bar, but then intensified the reducing trends of its germination indices and finally reached to zero at -14 bar treatment. Moreover, salinity stress especially treatments of higher than 100 mmol decreased all germination indices of grasspea. Overall, arugula was a more tolerant plant especially to osmotic stress; therefore this forgotten plant can be used in agronomic and breeding programs in areas affected by drought stress.

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Regulation of enzymatic and non-enzymatic antioxidants contributes to salt tolerance in hitherto unknown upland farmer rice varieties.

Current Botany ◽

10.25081/cb.2020.v11.6019 ◽

2020 ◽

pp. 18-27

Author(s):

Lins Simon ◽

Yusuf Akkara

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Stability Index ◽

Monodehydroascorbate Reductase ◽

Enzymatic Antioxidants ◽

Salt Tolerant ◽

Sod Activity ◽

Rice Varieties ◽

Pronounced Increase ◽

Nacl Concentration

Salt tolerance potential of the three upland farmer varieties, koduvelliyan, mullankayama and marathondi was evaluated by comparing with the released salt-tolerant pokkali variety, vytilla-2. The salt tolerance exhibited by the upland varieties was identical with the salt tolerant variety. The superoxide (O2-) content in the upland varieties was lower; however, the hydrogen peroxide (H2O2) content increased with the salt concentration. The lesser malondialdehyde (MDA) content in the koduvelliyan variety was equivalent to the vytilla-2 and slight increase was observed in mullankayama and marathondi. The ascorbate (AsA) content in the upland varieties was comparable to vytilla-2 and upon exposure to increased concentration of NaCl, the AsA level reduced in all the treatments. Reduced glutathione (GSH) content was uniform in all the varieties up to a concentration of 100mM NaCl, however, in 125-150mM NaCl, mullankayama showed a pronounced increase in GSH content. Under salt stress, due to the formation of O2-, the oxidation of GSH was higher, maintaining a stable GSH/GSSG ratio. Superoxide dismutase (SOD) and catalase (CAT) activity of the upland varieties was higher than vytilla-2 up to 100mM NaCl, however, in 125-150mM NaCl the SOD activity increased slightly and the CAT activity decreased. Ascorbate peroxidase (APX) activity increased in upland varieties up to 125mM NaCl, and in 150mM NaCl, maintained a steady level in all the varieties. Glutathione reductase (GR) activity increased proportionate with NaCl concentration; with highest activity in all the upland varieties. Monodehydroascorbate reductase (MDHAR) activity was uniform in all the varieties up to 100mM NaCl, however, in 125 and 150mM NaCl, vytilla-2 showed higher MDHAR activity. Dehydroascorbate reductase (DHAR) activity was lesser in upland varieties under salt stress compared to vytilla-2. The GSH/GSSG ratio decreased in marathondi and koduvelliyan varieties with the increase in NaCl concentration, however, in mullankayama and vytilla-2, the GSH/GSSG ratio was higher. The membrane stability index of all the varieties was uniform in all the concentrations of NaCl used, except marathondi. The Na+ content in all the varieties increased in relation to NaCl concentration and the K+ efflux was higher suggesting a higher Na+/K+ ratio, with increased NaCl concentration.

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GROWTH AND MINRAL STATUS OF COTTON PLANTS AS AFFECTED BY ABSICISIC ACID AND SALT STRESS

International Journal of Engineering Technologies and Management Research ◽

10.29121/ijetmr.v6.i5.2019.381 ◽

2020 ◽

Vol 6 (5) ◽

pp. 142-153

Author(s):

Safaa A. Mahmoud ◽

Hussein M.M. ◽

A.S. Taalab ◽

Hanan S. Siam

Keyword(s):

Cotton Plant ◽

Salinity Stress ◽

Sea Water ◽

Tap Water ◽

Harmful Effect ◽

Foliar Spray ◽

Dry Weight ◽

Control Treatment ◽

Cotton Plants ◽

Salinity Levels

Application of antioxidant materials like absicisic acid to alleviate salinity stress and promote cotton growth is high effectiveness target, whereas cotton plant is an attractive industrial crop. Pot experiment was conducted to evaluate the effect of salinity stress and absicisic acid (antioxidant materials to alleviate salinity stress) on cotton growth and macro nutrients status in shoots of cotton plants. Plants subjected to two salinity levels (2500 and 5000 ppm as diluted sea water), and tap water (250ppm) as control, sprayed absicisic acid (ABA) with two concentrations (20 and 40 ppm of ABA) and distilled water as a control. Salinity decreased stem and leaves dry weight compare to the control treatment. The lower concentrations of ABA (20 and 40 ppm as a foliar spray) improve dry weight of stem and leaves. Reversely, leaves/stem ratio decreased with both concentrations of the absicisic acid. The increment in dry weight of leaves and stem or their sum showed its higher values by application 40 ppm from ABA under the 5000 ppm salinity level and also under fresh water treatment but under the 2500 ppm treatment the highest values were by 20 ppm of growth regulator. Nevertheless, L/S ratio decreased by ABA treatment, whereas, the high concentration of ABA (40ppm) was super than lower concentration (20ppm) under both salinity levels. Generally, it can be used diluted seawater in irrigation of cotton plant with spraying abscisic acid to alleviate the harmful effect of salinity.

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Physiological response of Bajra-Napier Hybrids and Tri-Specific Hybrid to salinity stressPhysiological response of Bajra-Napier Hybrids and Tri-Specific Hybrid to salinity stress

Tropical Grasslands - Forrajes Tropicales ◽

10.17138/tgft(9)337-347 ◽

2021 ◽

Vol 9 (3) ◽

pp. 337-347

Author(s):

Seva Nayak Dheeravathu ◽

Kajal Singh ◽

Pramod W. Ramteke ◽

Reetu - ◽

Nilamani Dikshit ◽

...

Keyword(s):

Salinity Stress ◽

Stability Index ◽

Dry Weight ◽

Salinity Level ◽

Shoot Dry Weight ◽

Randomized Design ◽

Relative Water ◽

Salinity Levels ◽

K Concentration ◽

Specific Hybrid

Physiological responses of 3 Bajra-Napier (Cenchrus spp., syn. Pennisetum spp.) hybrid varieties, viz. BNH-3, BNH-6, BNH-10, and 1 ttri-specific hybrid (TSH) were tested under different gradients of soil salinity, i.e. Control, 4, 6 and 8 dS/m electric conductivity (EC), in a pot trial. The experiment was laid out in a factorial completely randomized design with 3 replications. Shoot dry weight, root dry weight, root:shoot ratio and chlorophyll a, chlorophyll b, total chlorophyll and carotenoid concentrations were reduced with increasing salinity level as compared with Control. However, the concentration of Na+ in leaves increased and K+ concentration decreased with increasing salinity level. Physiological parameters, i.e. relative water content (RWC), membrane stability index (MSI), chlorophyll stability index, carotenoid stability index and K+: Na+ ratio, in leaves tended to be higher in the BNH-3 variety than in other varieties. Shoot dry weight showed highly positive significant correlation with RWC, MSI, K+ concentration and K+:Na+ ratio, while it was negatively correlated with Na+ concentration (P<0.01) All BN hybrid varieties and the tri-specific hybrid studied were susceptible to salinity stress, showing marked reductions in growth as the level of salinity increased above 4 dS/m. However, even at salinity levels producing EC of 8 dS/m these varieties still produced 25‒44% DM yields. There are prospects for improving forage yields from saline soils by planting these hybrids but further breeding studies are warranted to identify germplasm with greater tolerance of saline conditions if these soils are to be utilized effectively to contribute more to supplying forage to support the world’s ruminant population.

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Responses ofJatropha curcasto Salt and Drought Stresses

International Journal of Agronomy ◽

10.1155/2012/632026 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 13

Author(s):

Genhua Niu ◽

Denise Rodriguez ◽

Mike Mendoza ◽

John Jifon ◽

Girisha Ganjegunte

Keyword(s):

Salinity Stress ◽

Leaf Development ◽

Deficit Irrigation ◽

Dry Weight ◽

Control Treatment ◽

Growth Responses ◽

Elevated Salinity ◽

Total Dry Weight ◽

Saline Solutions ◽

Salt And Drought Stresses

Two greenhouse experiments were conducted to quantify growth responses ofJatropha curcasto a range of salt and drought stresses. Typical symptoms of salinity stress such as leaf edge yellowing were observed in all elevated salinity treatments and the degree of the foliar salt damage increased with the salinity of irrigation water. Total dry weight (DW) of Jatropha plants was reduced by 30%, 30%, and 50%, respectively, when irrigated with saline solutions at electrical conductivity of 3.0, 6.0, and 9.0 dSm−1compared to that in the control. LeafNa+concentration was much higher than that observed in most glycophytes. LeafCl−concentrations were also high. In the drought stress experiment, plants were irrigated daily with nutrient solution at 100%, 70%, 50%, or 30% daily water use (DWU). Deficit irrigation reduced plant growth and leaf development. The DW of leaves, roots, and total were reduced in the 70%, 50%, and 30% DWU compared to the 100% DWU control treatment. In summary, salinity stress and deficit irrigation significantly reduced the growth and leaf development of greenhouse-grown Jatropha plants.

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