glyoxalase system

Soybean plants grown under NaCl were foliar sprayed twice with melatonin (MLT). Results revealed that salt stress reduced growth, biomass accumulation, photosynthesis, mineral uptake, the content of δ-aminolevulinic acid, chlorophylls, carotenoids and PSII efficiency. However, MLT application enhanced pigment synthesis and PSII activity. MLT up-regulated the antioxidant system and glyoxalase function resulting in reduced accumulation of reactive oxygen species (ROS). Reduced ROS in MLT-treated plants protected membrane functioning by reducing lipid peroxidation, electrolyte leakage and lipoxygenase activity. Nevertheless, MLT application reduced methylglyoxal accumulation while increased the content of reduced glutathione and ascorbic acid. It could be concluded that exogenous MLT mitigated the salt stress damage in soybean plants by improving photosynthesis, antioxidant systems, controlling ion homeostasis and minimising excessive ROS accumulation.  

Salt stress is one of major problem hampering plant growth and development to a significant level. In present study, 5-aminolevulinic acid (ALA) was exogenously applied to Leymus chinensis (Trin.) Tzvel. plants at various concentrations (10, 50, and 100 mg L-1) to assess its effects on morphology, physiology, and biochemistry under salt stress conditions (150 mmol NaCl L-1) as compared with control. The results indicated that salt stress substantially impaired growth, physiology and biochemistry of L. chinensis plants; nonetheless, ALA application alleviated the adverse effects of salt stress. Application of ALA improved the leaf length, leaf area, leaf conductance, plant dry biomass, water contents, and root activity of L. chinensis under stress and no stress conditions. Additionally, biosynthesis of chlorophyll, carotenoids, free proline, soluble sugars and proteins of L. chinensis plants was also increased following ALA application as compared to control, under salt stress conditions. Moreover, we also observed an enhanced activity of antioxidant defense system in L. chinensis in response to ALA application. ALA elevated the activity of enzymatic antioxidants viz. ascorbate peroxidase (APX), glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) significantly scavenged reactive oxygen species thus reduced the accumulation of malondialdehyde (MDA) under salt stress as compared to control under both normal and stressed conditions. The effect of ALA on all growth and biochemical attributes was concentration dependent and application of 50 as well as 100 mg L-1 ALA proved better. The results concluded that salt stress tolerance in L. chinensis plants can be increased by exogenously applied ALA at appropriate concentration. It was suggested that L. chinensis plants were treated with ALA application of 50-100 mg L-1 was more beneficial under both normal and saline conditions.

Exogenous application of selenium (Se) is an effective approach to improve abiotic stresses under climate change scenario. To investigate the effects of Se-induced improvement of cold tolerance, waxy maize seedlings sprayed with varied Se dose (0, 30, 60, 90 mg L -1 ) were exposed to low temperature (13 °C, LT) and ambient temperature (25 °C, NT) for ten days. The plant growth performances, such as net photosynthetic rate (A n ), oxidative damage, enzymes activities and related gene expression, and non-enzymatic levels of AsA and GSH were evaluated. The results showed that LT induced higher levels of hydrogen peroxide (H 2 O 2) , superoxide (O 2 •−), and decreased membrane stability index (MSI), An, leaf area (LA) and shoot dry weight (SDW) compared to NT, while Se-sprayed plants displayed higher antioxidant enzymes activities of SOD, CAT, APX and GR, and up-granulated genes encoding these four proteins, as well the increased contents of AsA, GSH and GSH+GSSG under LT, thereby decre...

Salt stress is one of major problem hampering plant growth and development to a significant level. In present study, 5-aminolevulinic acid (ALA) was exogenously applied to Leymus chinensis (Trin.) Tzvel. plants at various concentrations (10, 50, and 100 mg L-1) to assess its effects on morphology, physiology, and biochemistry under salt stress conditions (150 mmol NaCl L-1) as compared with control. The results indicated that salt stress substantially impaired growth, physiology and biochemistry of L. chinensis plants; nonetheless, ALA application alleviated the adverse effects of salt stress. Application of ALA improved the leaf length, leaf area, leaf conductance, plant dry biomass, water contents, and root activity of L. chinensis under stress and no stress conditions. Additionally, biosynthesis of chlorophyll, carotenoids, free proline, soluble sugars and proteins of L. chinensis plants was also increased following ALA application as compared to control, under salt stress conditions. Moreover, we also observed an enhanced activity of antioxidant defense system in L. chinensis in response to ALA application. ALA elevated the activity of enzymatic antioxidants viz. ascorbate peroxidase (APX), glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) significantly scavenged reactive oxygen species thus reduced the accumulation of malondialdehyde (MDA) under salt stress as compared to control under both normal and stressed conditions. The effect of ALA on all growth and biochemical attributes was concentration dependent and application of 50 as well as 100 mg L-1 ALA proved better. The results concluded that salt stress tolerance in L. chinensis plants can be increased by exogenously applied ALA at appropriate concentration. It was suggested that L. chinensis plants were treated with ALA application of 50-100 mg L-1 was more beneficial under both normal and saline conditions.

Soybean plants grown under NaCl were foliar sprayed twice with melatonin (MLT). Results revealed that salt stress reduced growth, biomass accumulation, photosynthesis, mineral uptake, the content of δ-aminolevulinic acid, chlorophylls, carotenoids and PSII efficiency. However, MLT application enhanced pigment synthesis and PSII activity. MLT up-regulated the antioxidant system and glyoxalase function resulting in reduced accumulation of reactive oxygen species (ROS). Reduced ROS in MLT-treated plants protected membrane functioning by reducing lipid peroxidation, electrolyte leakage and lipoxygenase activity. Nevertheless, MLT application reduced methylglyoxal accumulation while increased the content of reduced glutathione and ascorbic acid. It could be concluded that exogenous MLT mitigated the salt stress damage in soybean plants by improving photosynthesis, antioxidant systems, controlling ion homeostasis and minimising excessive ROS accumulation.  

The present study was conducted to evaluate the ameliorating effect of 5-aminolevulinic acid (ALA) on physiological and biochemical changes of induced NaCl-salinity stress on in vitro shoot and callus cultured of red-fleshed apple. Shoot and callus segments of the red-flesh apple of Local Iranian genotype were cultured on MS medium containing different levels of NaCl (0, 30, 60 and 90 mM) and ALA (0, 2.5, 5, 10 and 20 µM). Physiological and biochemical variations of treated explants with or without NaCl and ALA treatments were recorded. In both explants, salinity reduced chlorophyll and carotenoids contents, but the activities of antioxidant enzymes and accumulation of total phenol and anthocyanin increased with increasing salinity level (90mM). Exogenous ALA in 5 and particularly in 10 µM was effective in enhancing chlorophyll and carotenoids contents, increasing the activities of superoxide dismutase, ascorbate peroxidase and accumulating of total phenol and anthocyanin. These results indicate that ALA has a powerful salinity-ameliorating potential on in vitro cultured shoot and callus of Iranian red-fleshed apple.

Taurine functions as an essential ROS scavenger and thereby diminishes lipid peroxidation of biomembranes. Taurine also regulates osmoregulation. However, nothing is known about how taurine mediates plant defense mechanisms under drought and chromium (Cr) stress. Trifolium alexandrinum plants were exposed to individual and combined drought and Cr conditions. We have noticed a substantial decline in growth, photosynthetic pigments, SPAD values, and acquisition of essential nutrients. Further, the reduction in these attributes was more noteworthy in plants under combined Cr and drought conditions. The results also revealed a significant increase in oxidative damage reflected as a higher generation of reactive oxygen species, malondialdehyde, and enhanced lipoxygenase activity. The oxidative injury was more remarkable in plants under combined Cr and drought conditions. Antioxidant enzyme activities and levels of non-enzymatic compounds were several folds higher in plants administered taurine under Cr and drought conditions. Further, taurine regulated osmotic adjustment under drought by enhancing the accumulation of organic osmolytes. In Cr-stressed plants, taurine reduced Cr uptake and improved nutrient acquisition. Taurine administration (100 and 200 mg L-1) notably circumvented the effects of individual and combined Cr and drought on plants. Taurine lessened the oxidative injury, improved secondary metabolites accumulation, bettered nutrient uptake, and strengthened the oxidative defense, enabling plants to cope with drought and Cr stress.

Melatonin, a natural agent, has multiple functions in animals as well as in plants. However, its possible roles in plants under abiotic stress are not clear. Nowadays, soil salinity is a major threat to global agriculture because a high soil salt content causes multiple stresses (hyperosmotic, ionic, and oxidative). Therefore, the aim of the present study was to explore: (1) the involvement of melatonin in biosynthesis of photosynthetic pigments and in regulation of photosynthetic enzymes, such as carbonic anhydrase (CA) and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco); (2) the role of melatonin in osmoregulation by proline and carbohydrate metabolism; and (3) the function of melatonin in the antioxidant defense system under salinity. Outcomes of the study reveal that under non-saline conditions, application of melatonin (20 and 50 µM) improved plant growth, viz. shoot length, root length, shoot fresh weight (FW), root FW, shoot dry weight (DW), root DW and leaf area an...

Soybean plants grown under NaCl were foliar sprayed twice with melatonin (MLT). Results revealed that salt stress reduced growth, biomass accumulation, photosynthesis, mineral uptake, the content of δ-aminolevulinic acid, chlorophylls, carotenoids and PSII efficiency. However, MLT application enhanced pigment synthesis and PSII activity. MLT up-regulated the antioxidant system and glyoxalase function resulting in reduced accumulation of reactive oxygen species (ROS). Reduced ROS in MLT-treated plants protected membrane functioning by reducing lipid peroxidation, electrolyte leakage and lipoxygenase activity. Nevertheless, MLT application reduced methylglyoxal accumulation while increased the content of reduced glutathione and ascorbic acid. It could be concluded that exogenous MLT mitigated the salt stress damage in soybean plants by improving photosynthesis, antioxidant systems, controlling ion homeostasis and minimising excessive ROS accumulation.  

Fluoride (F) is considered one of the most phytotoxic pollutants, even when present in low concentrations. When dispersed in the air, F can be transported to about 100 km from the polluting source, reaching plants, animals and humans and causing serious damage. Nevertheless, studies are still scarce on the effect of fluoride in Cerrado species integrating morphological, anatomical and physiological responses. Therefore, this study aimed to investigate the effect of simulated rainfall containing potassium fluoride (KF) on Hancornia speciosa leaves and roots, to determine its bioaccumulator potential. Young plants at approximately 45 days of emergence were treated daily with simulated KF rain at four concentrations (0, 4, 8 and 12 mg L −1), and four replicates. The experiment was carried out for 40 days, in completely randomized design. After KF exposure, visual, morphological and chlorophyll a fluorescence analyses were performed, alongside fluoride accumulation assessments in roots and shoots. Hancornia speciosa did not present any visual, anatomical and physiological symptoms in response to fluoride; however, it showed an accumulation of phenolic compounds in mesophyll root and leaf cells in all treatments. Physiological characteristic preservation and fluoride accumulation in roots and leaves allow us to suggest that Hancornia speciosa displays tolerance potential at the investigated doses.

Salt stress is one of major problem hampering plant growth and development to a significant level. In present study, 5-aminolevulinic acid (ALA) was exogenously applied to Leymus chinensis (Trin.) Tzvel. plants at various concentrations (10, 50, and 100 mg L-1) to assess its effects on morphology, physiology, and biochemistry under salt stress conditions (150 mmol NaCl L-1) as compared with control. The results indicated that salt stress substantially impaired growth, physiology and biochemistry of L. chinensis plants; nonetheless, ALA application alleviated the adverse effects of salt stress. Application of ALA improved the leaf length, leaf area, leaf conductance, plant dry biomass, water contents, and root activity of L. chinensis under stress and no stress conditions. Additionally, biosynthesis of chlorophyll, carotenoids, free proline, soluble sugars and proteins of L. chinensis plants was also increased following ALA application as compared to control, under salt stress conditions. Moreover, we also observed an enhanced activity of antioxidant defense system in L. chinensis in response to ALA application. ALA elevated the activity of enzymatic antioxidants viz. ascorbate peroxidase (APX), glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) significantly scavenged reactive oxygen species thus reduced the accumulation of malondialdehyde (MDA) under salt stress as compared to control under both normal and stressed conditions. The effect of ALA on all growth and biochemical attributes was concentration dependent and application of 50 as well as 100 mg L-1 ALA proved better. The results concluded that salt stress tolerance in L. chinensis plants can be increased by exogenously applied ALA at appropriate concentration. It was suggested that L. chinensis plants were treated with ALA application of 50-100 mg L-1 was more beneficial under both normal and saline conditions.

Soybean plants grown under NaCl were foliar sprayed twice with melatonin (MLT). Results revealed that salt stress reduced growth, biomass accumulation, photosynthesis, mineral uptake, the content of δ-aminolevulinic acid, chlorophylls, carotenoids and PSII efficiency. However, MLT application enhanced pigment synthesis and PSII activity. MLT up-regulated the antioxidant system and glyoxalase function resulting in reduced accumulation of reactive oxygen species (ROS). Reduced ROS in MLT-treated plants protected membrane functioning by reducing lipid peroxidation, electrolyte leakage and lipoxygenase activity. Nevertheless, MLT application reduced methylglyoxal accumulation while increased the content of reduced glutathione and ascorbic acid. It could be concluded that exogenous MLT mitigated the salt stress damage in soybean plants by improving photosynthesis, antioxidant systems, controlling ion homeostasis and minimising excessive ROS accumulation.  

Arable land contamination with nickel (Ni) has become a major threat to worldwide crop production. Recently, melatonin has appeared as a promising stress-relief substance that can alleviate heavy metal-induced phytotoxicity in plants. However, the plausible underlying mechanism of melatonin function under Ni stress has not been fully substantiated in plants. Herein, we conducted an experiment that unveiled critical mechanisms in favor of melatonin-mediated Ni-stress tolerance in tomato. Ni stress markedly inhibited growth and biomass by impairing the photosynthesis, photosystem function, mineral homeostasis, root activity, and osmotic balance. In contrast, melatonin application notably reinforced the plant growth traits, increased photosynthesis efficiency in terms of chlorophyll content, upregulation of chlorophyll synthesis genes, i.e. POR, CAO, CHL G, gas exchange parameters, and PSII maximum efficiency (Fv/Fm), decreased Ni accumulation and increased mineral nutrient homeostasis. Moreover, melatonin efficiently restricted the hydrogen peroxide (H 2 O 2) and superoxide radical production and increased RBOH expression and restored cellular integrity (less malondialdehyde and electrolyte leakage) through triggering the antioxidant enzyme activities and modulating AsA-GSH pools. Notably, oxidative stress was effectively mitigated by upregulation of several defense genes (SOD, CAT, APX, GR, GST, MDHAR, DHAR) and melatonin biosynthesis-related genes (TDC, T5S, SNAT, ASMT). Besides, melatonin treatment enhanced secondary metabolites (phenols, flavonoids, and anthocyanin) contents along with their encoding genes (PAL, CHS) expression, and these metabolites potentially restricted excess H 2 O 2 accumulation. In conclusion, our findings deciphered the potential functions of melatonin in alleviating Ni-induced phytotoxicity in tomato through boosting the biomass production, photosynthesis, nutrient uptake, redox balance, and secondary metabolism.

The purpose of the present study is to investigate the role of hydrogen sulfide (H2S), in improving resistance to common bean salt stress. Method shows that common bean seeds were soaked in water and in two concentrations of sodium hydrosulfide (50 and 100 µM) for 8 h. After 25 days from sowing, the pots were irrigated with water and with two concentrations of NaCl (75 and 150 mM) until the end of the experiment. Results revealed that H2S relieved salt stress by decreasing growth inhibition and photosynthetic characteristics, and increasing osmolyte contents (proline and glycine betaine). Furthermore, H2S reduced oxidative damage by lowering lipid peroxidation, electrolyte leakage, and reactive oxygen species production such as hydrogen peroxide, hydroxyl radicals, and superoxide anion by increasing non-enzymatic antioxidants such as ascorbic acid and glutathione, as well as enzymatic antioxidants such as superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbate peroxi...

The purpose of the present study is to investigate the role of hydrogen sulfide (H2S), in improving resistance to common bean salt stress. Method shows that common bean seeds were soaked in water and in two concentrations of sodium hydrosulfide (50 and 100 µM) for 8 h. After 25 days from sowing, the pots were irrigated with water and with two concentrations of NaCl (75 and 150 mM) until the end of the experiment. Results revealed that H2S relieved salt stress by decreasing growth inhibition and photosynthetic characteristics, and increasing osmolyte contents (proline and glycine betaine). Furthermore, H2S reduced oxidative damage by lowering lipid peroxidation, electrolyte leakage, and reactive oxygen species production such as hydrogen peroxide, hydroxyl radicals, and superoxide anion by increasing non-enzymatic antioxidants such as ascorbic acid and glutathione, as well as enzymatic antioxidants such as superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbate peroxi...

This work focused on the effect triterpene derivative 24-methylen-elemo-lanosta-8,24-dien-3-one (F3) on the induction of salt stress tolerance of the Moroccan grapevine cv. "Doukkali". Hardwood cuttings of the grapevine from a homogeneous plant material collected in the field were grown in hydroponic medium under different salt concentrations and treated with 50 or 100 µg ml −1 of F3. Salt stress affected several physiological and biochemical parameters including relative water content, chlorophyll a and b content, peroxidase, and polyphenol oxidase activities, which decreased along with time. Meanwhile, proline, proteins, soluble sugars, H 2 O 2 , and carotenoid content, as well as phenolic compound content increased, suggesting an evidence of tolerance of this local variety to salinity. An exogenous supply of the triterpenic product increased all these parameters under normal conditions. In addition, F3 at low dose was found to be successful in lowering Na + content and alleviating the inhibitory effects of salt stress on relative water content as well as on chlorophyll a and b.

Soil not only represents the main supporter for root growth, but also is the supplier of water and nutrients. However, several soils, i.e. sandy soils, do not adequately fulfill the plant growth requirements of the environmental resources. Therefore, it is necessary to compensate, even partially, the lack of these required resources for better plant growth and development. Amino acids could introduce a substantial solution in this respect. Therefore, two field experiments under field conditions were carried out to investigate the effect of glutamic (GLA) and 5‑aminolevulinic (ALA) acids on photosynthesis pigments, oxidative defense indicators as well as yield and seed quality of peanut. Three concentrations of glutamic acid (10, 20 and 40 mg L−1, denoted GLA10, GLA20, and GLA40, respectively) and three concentrations of 5‑aminolevulinic acid, (10, 20 and 40 mg L−1, abbreviated to ALA10, ALA20, and ALA40, respectively), in addition to a check treatment (tap water) were applied. Treat...

Salt stress is one of major problem hampering plant growth and development to a significant level. In present study, 5-aminolevulinic acid (ALA) was exogenously applied to Leymus chinensis (Trin.) Tzvel. plants at various concentrations (10, 50, and 100 mg L-1) to assess its effects on morphology, physiology, and biochemistry under salt stress conditions (150 mmol NaCl L-1) as compared with control. The results indicated that salt stress substantially impaired growth, physiology and biochemistry of L. chinensis plants; nonetheless, ALA application alleviated the adverse effects of salt stress. Application of ALA improved the leaf length, leaf area, leaf conductance, plant dry biomass, water contents, and root activity of L. chinensis under stress and no stress conditions. Additionally, biosynthesis of chlorophyll, carotenoids, free proline, soluble sugars and proteins of L. chinensis plants was also increased following ALA application as compared to control, under salt stress conditions. Moreover, we also observed an enhanced activity of antioxidant defense system in L. chinensis in response to ALA application. ALA elevated the activity of enzymatic antioxidants viz. ascorbate peroxidase (APX), glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) significantly scavenged reactive oxygen species thus reduced the accumulation of malondialdehyde (MDA) under salt stress as compared to control under both normal and stressed conditions. The effect of ALA on all growth and biochemical attributes was concentration dependent and application of 50 as well as 100 mg L-1 ALA proved better. The results concluded that salt stress tolerance in L. chinensis plants can be increased by exogenously applied ALA at appropriate concentration. It was suggested that L. chinensis plants were treated with ALA application of 50-100 mg L-1 was more beneficial under both normal and saline conditions.

Rice (Oryza sativa L.) is the staple food for nearly half of the world's population and is cultivated in approximately 160 million hectares of land globally, mostly in Asia, where about 46.6% of the world population resides (Prasad et al. 2017). As the world population is increasing alarmingly fast, it is an earnest need to increase the rice production several folds to feed the population. In contrast, rice is a drought-sensitive crop, and every year encounters a vast amount of yield loss globally. Moreover, climate change has been altering the rainfall pattern; thereby, at present, drought has become a very serious concern for rice farming (Fahad et al. 2017, 2019). Drought impedes plant productivity by altering the physiological processes. It causes the generation of the excessive amount of reactive oxygen species (ROS), which alters the metabolic and oxidative homeostasis of plant cells (Hussain et al. 2018). Later, excessive

Soybean plants grown under NaCl were foliar sprayed twice with melatonin (MLT). Results revealed that salt stress reduced growth, biomass accumulation, photosynthesis, mineral uptake, the content of δ-aminolevulinic acid, chlorophylls, carotenoids and PSII efficiency. However, MLT application enhanced pigment synthesis and PSII activity. MLT up-regulated the antioxidant system and glyoxalase function resulting in reduced accumulation of reactive oxygen species (ROS). Reduced ROS in MLT-treated plants protected membrane functioning by reducing lipid peroxidation, electrolyte leakage and lipoxygenase activity. Nevertheless, MLT application reduced methylglyoxal accumulation while increased the content of reduced glutathione and ascorbic acid. It could be concluded that exogenous MLT mitigated the salt stress damage in soybean plants by improving photosynthesis, antioxidant systems, controlling ion homeostasis and minimising excessive ROS accumulation.  

Background Application of exogenous glycine betaine (GB) and exogenous salicylic acid (SA) mitigates the adverse effects of salinity. Foliar spraying with exogenous GB or SA alleviates salt stress in plants by increasing leaf gas exchange and stimulating antioxidant enzyme activity. The effects of foliar application of exogenous GB and SA on the physiology and biochemistry of cotton seedlings subjected to salt stress remain unclear. Results Results showed that salt stress of 150 mM NaCl significantly reduced leaf gas exchange and chlorophyll fluorescence and decreased photosynthetic pigment quantities and leaf relative water content. Foliar spray concentrations of 5.0 mM exogenous GB and 1.0 mM exogenous SA promoted gas exchange and fluorescence in cotton seedlings, increased quantities of chlorophyll pigments, and stimulated the antioxidant enzyme activity. The foliar spray also increased leaf relative water content and endogenous GB and SA content in comparison with the salt-stres...

Drought stress is a significant abiotic stressor that has a negative impact on crop production and global food security systems. Drought stress was applied to eggplant seedlings with various field capacities (FC), 80% FC as control, 50% FC, 35% FC, and 20% FC. AgNPs were synthesised from green chemical methods, whereas different concentrations of AgNPs (0, 0.1, 0.2, 0.5 µmol) were applied exogenously on drought-stressed eggplants. Drought stress decreased the growth parameters (plant height, fresh mass, dry mass, leaf area), photosynthetic pigments (Chl a, Chl b, carotenoids), and protein content while increased the proline, hydrogen peroxide (H2O2), malondialdehyde (MDA) content, and activity of the antioxidant enzymes, i.e., superoxide dismutase (SOD) and catalase (CAT). AgNPs restricted proline accumulation and reduced H2O2, MDA content by upregulating the antioxidant enzymes. Overall, the current study’s findings indicated that AgNPs are an effective eco-friendly and low-cost ap...

Melatonin, a natural agent, has multiple functions in animals as well as in plants. However, its possible roles in plants under abiotic stress are not clear. Nowadays, soil salinity is a major threat to global agriculture because a high soil salt content causes multiple stresses (hyperosmotic, ionic, and oxidative). Therefore, the aim of the present study was to explore: (1) the involvement of melatonin in biosynthesis of photosynthetic pigments and in regulation of photosynthetic enzymes, such as carbonic anhydrase (CA) and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco); (2) the role of melatonin in osmoregulation by proline and carbohydrate metabolism; and (3) the function of melatonin in the antioxidant defense system under salinity. Outcomes of the study reveal that under non-saline conditions, application of melatonin (20 and 50 µM) improved plant growth, viz. shoot length, root length, shoot fresh weight (FW), root FW, shoot dry weight (DW), root DW and leaf area an...

The aim of this work was to examine the ameliorative effect of foliar application of salicylic acid and potassium on antioxidant enzymes activity in wheat under saline conditions. Two wheat genotypes WL-711 (salt tolerant) and Kohistan-97 (salt sensitive) were used with salicylic acid (SA) and potassium (K+) foliar spray which were applied at both vegetative and grain filling stage under saline conditions. Various enzymatic antioxidant activities include catalase (CAT), peroxidase (POD), superoxide dismutase (SOD) and ascorbate peroxidase (APX) was assesed. Result cleared that foliar spray of salicylic acid and potassium decreased the damaged effect of salinity in both wheat genotypes especially Kohistan-97 which was more salt sensitive. Overall, foliarly applied salicylic acid and potassium reduces the adverse effects of reactive oxygen species and antioxidant enzymes on cellular metabolism that was disturbed by salt stress.

With the establishment of advanced technology facilities for high throughput plant phenotyping, the problem of estimating plant biomass of individual plants from their two dimensional images is becoming increasingly important. The approach predominantly cited in literature is to estimate the biomass of a plant as a linear function of the projected shoot area of plants in the images. However, the estimation error from this model, which is solely a function of projected shoot area, is large, prohibiting accurate estimation of the biomass of plants, particularly for the salt-stressed plants. In this paper, we propose a method based on plant specific weight for improving the accuracy of the linear model and reducing the estimation bias (the difference between actual shoot dry weight and the value of the shoot dry weight estimated with a predictive model). For the proposed method in this study, we modeled the plant shoot dry weight as a function of plant area and plant age. The data used for developing our model and comparing the results with the linear model were collected from a completely randomized block design experiment. A total of 320 plants from two bread wheat varieties were grown in a supported hydroponics system in a greenhouse. The plants were exposed to two levels of hydroponic salt treatments (NaCl at 0 and 100 mM) for 6 weeks. Five harvests were carried out. Each time 64 randomly selected plants were imaged and then harvested to measure the shoot fresh weight and shoot dry weight. The results of statistical analysis showed that with our proposed method, most of the observed variance can be explained, and moreover only a small difference between actual and estimated shoot dry weight was obtained. The low estimation bias indicates that our proposed method can be used to estimate biomass of individual plants regardless of what variety the plant is and what salt treatment has been applied. We validated this model on an independent set of barley data. The technique presented in this paper may extend to other plants and types of stresses.

Hydrogen peroxide (H2O2) and salicylic acid (SA) exhibit protective effects against a wide array of stresses. In this study, we investigated the relative efficacy of exogenous H2O2 and SA in conferring drought tolerance in rice (Oryza sativa L.). The experiment was repeated two times, firstly in a hydroponic system and secondly in soil. The results revealed that drought hampered germination indices, seedling growth, photosynthetic pigments, and water content, whereas increased proline content. It also triggered higher H2O2 production and consequently elevated lipid peroxidation, which is a particular indication of oxidative damage. However, exogenous H2O2 or SA treatment effectively alleviated oxidative damage in rice seedlings both in hydroponic and soil systems via upregulating antioxidant enzymes. Nevertheless, regulation of proline level and augmentation of plant-water status were crucial to confer drought tolerance. Exogenous H2O2 or SA also protected photosynthetic pigments fr...

Alpinia zerumbet is an important medicinal and ornamental plant species. Drought stress is a major concern for sustainable horticulture crop production under changing climate scenarios. Trehalose (Tre) and 5-aminolevulinic acid (ALA) are osmoprotectants that play important roles in mitigating plant stresses. In this study, the effects of foliar application of 25 mM Tre or 10 mg L−1 ALA on biochemical and physiological parameters of A. zerumbet seedlings and their growth were evaluated under well-watered and drought-stressed (65% of field capacity) conditions. Drought caused reductions in physiological parameters and plant growth. These decreases were accompanied by increases in leaf free proline and glycine betaine concentrations and peroxidase activities. Foliar application of Tre or ALA remediated physiological and biochemical parameters and plant growth. Overall, foliar application of ALA or Tre proved to be beneficial for mitigating drought stress in A. zerumbet.

In order to investigate the effects of methanol and glycine betaine application on quality traits and yield of different fodder beet cultivars, the experiment was performed as a combined split-factorial design based on randomized complete block design with 3 replications in two years in Isfahan, Iran. The concentrations of methanol in 3 levels (control, 15 and 30% v/v methanol) were considered as the first treatment, the concentrations of glycine betaine in 2 levels (control and 4 g per liter) as the second treatment and different cultivars (‘Sentinel’, ‘Drafter’, ‘Rivolta’, ‘Elanta’, ‘Rasta’, and ‘Qualita’) were considered as the factorial. Foliar spraying was performed at three intervals every two weeks. The results showed that the methanol spraying affected on root yield, sugar, potassium and sodium content, catalase enzyme activity, superoxide dismutase, rubisco, and malondialdehyde significantly. Glycine betaine foliar application showed significant differences in root yield, s...

In order to investigate the effects of methanol and glycine betaine application on quality traits and yield of different fodder beet cultivars, the experiment was performed as a combined split-factorial design based on randomized complete block design with 3 replications in two years in Isfahan, Iran. The concentrations of methanol in 3 levels (control, 15 and 30% v/v methanol) were considered as the first treatment, the concentrations of glycine betaine in 2 levels (control and 4 g per liter) as the second treatment and different cultivars (‘Sentinel’, ‘Drafter’, ‘Rivolta’, ‘Elanta’, ‘Rasta’, and ‘Qualita’) were considered as the factorial. Foliar spraying was performed at three intervals every two weeks. The results showed that the methanol spraying affected on root yield, sugar, potassium and sodium content, catalase enzyme activity, superoxide dismutase, rubisco, and malondialdehyde significantly. Glycine betaine foliar application showed significant differences in root yield, s...

Exogenous antioxidant applications enable salt-stressed plants to successfully cope with different environmental stresses. The objectives of this investigation were to study the effects of sequential treatments of proline (Pro), ascorbic acid (AsA), and/or glutathione (GSH) on 100 mM NaCl-stressed cucumber transplant’s physio-biochemical and growth traits as well as systems of antioxidant defense. Under salinity stress, different treatment of AsA, Pro, or/and GSH improved growth characteristics, stomatal conductance (gs), enhanced the activities of glutathione reductase (GR), superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT) as well as increased contents of AsA, Pro, and GSH. However, sequential application of antioxidants (GSH-Pro- AsA) significantly exceeded all individual applications, reducing leaf and root Cd2+ and Na+ contents in comparison to the control. In plants grown under NaCl-salt stress, growth characteristics, photosynthetic efficiency, membra...

With the establishment of advanced technology facilities for high throughput plant phenotyping, the problem of estimating plant biomass of individual plants from their two dimensional images is becoming increasingly important. The approach predominantly cited in literature is to estimate the biomass of a plant as a linear function of the projected shoot area of plants in the images. However, the estimation error from this model, which is solely a function of projected shoot area, is large, prohibiting accurate estimation of the biomass of plants, particularly for the salt-stressed plants. In this paper, we propose a method based on plant specific weight for improving the accuracy of the linear model and reducing the estimation bias (the difference between actual shoot dry weight and the value of the shoot dry weight estimated with a predictive model). For the proposed method in this study, we modeled the plant shoot dry weight as a function of plant area and plant age. The data used for developing our model and comparing the results with the linear model were collected from a completely randomized block design experiment. A total of 320 plants from two bread wheat varieties were grown in a supported hydroponics system in a greenhouse. The plants were exposed to two levels of hydroponic salt treatments (NaCl at 0 and 100 mM) for 6 weeks. Five harvests were carried out. Each time 64 randomly selected plants were imaged and then harvested to measure the shoot fresh weight and shoot dry weight. The results of statistical analysis showed that with our proposed method, most of the observed variance can be explained, and moreover only a small difference between actual and estimated shoot dry weight was obtained. The low estimation bias indicates that our proposed method can be used to estimate biomass of individual plants regardless of what variety the plant is and what salt treatment has been applied. We validated this model on an independent set of barley data. The technique presented in this paper may extend to other plants and types of stresses.

Exogenous antioxidant applications enable salt-stressed plants to successfully cope with different environmental stresses. The objectives of this investigation were to study the effects of sequential treatments of proline (Pro), ascorbic acid (AsA), and/or glutathione (GSH) on 100 mM NaCl-stressed cucumber transplant’s physio-biochemical and growth traits as well as systems of antioxidant defense. Under salinity stress, different treatment of AsA, Pro, or/and GSH improved growth characteristics, stomatal conductance (gs), enhanced the activities of glutathione reductase (GR), superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT) as well as increased contents of AsA, Pro, and GSH. However, sequential application of antioxidants (GSH-Pro- AsA) significantly exceeded all individual applications, reducing leaf and root Cd2+ and Na+ contents in comparison to the control. In plants grown under NaCl-salt stress, growth characteristics, photosynthetic efficiency, membra...

A field trial was conducted twice (in 2020 and 2021) to evaluate the effect of clove fruit extract (CFE) and/or salicylic acid (SA), which were used as a foliar nourishment, on growth and yield traits, as well as physiological and biochemical indices utilizing potato (Solanum tuberosum L.) plants irrigated with deficient regimes in an arid environment. Three drip irrigation regimes [e.g., well watering (7400 m3 ha−1), moderate drought (6200 m3 ha−1), and severe drought (5000 m3 ha−1)] were designed for this study. The tested growth, yield, and photosynthetic traits, along with the relative water content, were negatively affected, whereas markers of oxidative stress (hydrogen peroxide and superoxide), electrolyte leakage, and peroxidation of membrane lipids (assessed as malondialdehyde level) were augmented along with increased antioxidative defense activities under drought stress. These effects were gradually increased with the gradual reduction in the irrigation regime. However, un...

Drought stress is a significant abiotic stressor that has a negative impact on crop production and global food security systems. Drought stress was applied to eggplant seedlings with various field capacities (FC), 80% FC as control, 50% FC, 35% FC, and 20% FC. AgNPs were synthesised from green chemical methods, whereas different concentrations of AgNPs (0, 0.1, 0.2, 0.5 µmol) were applied exogenously on drought-stressed eggplants. Drought stress decreased the growth parameters (plant height, fresh mass, dry mass, leaf area), photosynthetic pigments (Chl a, Chl b, carotenoids), and protein content while increased the proline, hydrogen peroxide (H2O2), malondialdehyde (MDA) content, and activity of the antioxidant enzymes, i.e., superoxide dismutase (SOD) and catalase (CAT). AgNPs restricted proline accumulation and reduced H2O2, MDA content by upregulating the antioxidant enzymes. Overall, the current study’s findings indicated that AgNPs are an effective eco-friendly and low-cost ap...

Exogenous antioxidant applications enable salt-stressed plants to successfully cope with different environmental stresses. The objectives of this investigation were to study the effects of sequential treatments of proline (Pro), ascorbic acid (AsA), and/or glutathione (GSH) on 100 mM NaCl-stressed cucumber transplant’s physio-biochemical and growth traits as well as systems of antioxidant defense. Under salinity stress, different treatment of AsA, Pro, or/and GSH improved growth characteristics, stomatal conductance (gs), enhanced the activities of glutathione reductase (GR), superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT) as well as increased contents of AsA, Pro, and GSH. However, sequential application of antioxidants (GSH-Pro- AsA) significantly exceeded all individual applications, reducing leaf and root Cd2+ and Na+ contents in comparison to the control. In plants grown under NaCl-salt stress, growth characteristics, photosynthetic efficiency, membra...

ɑ-Tocopherol (ɑTOC) is a vitamin and antioxidant compound that plays a crucial role in amelioration of biotic and abiotic stresses. It has been found that it improves salt-tolerance in some plant species. Two field experiments were conducted in 2013/14 and 2014/15 to evaluate the potential effects of foliar applications with 0.5 and 1.0 mM ɑTOC on growth, yield, plant water relations, osmoprotectants and the activity of antioxidant system of two onion varieties (i.e., Giza 20 and Giza Red) "classified as salt-sensitive" under saline soil condition (EC e = 7.94-8.81 dS m-1). Exogenous application of ɑTOC significantly improved salt stress tolerance in onion plants by reducing the endogenous H 2 O 2 and lipid peroxidation, and increasing enzymatic (i.e., superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase) and non-enzymatic (i.e., ascorbic acid and glutathione) antioxidant activity. However, Giza 20 was more sensitive to salinity, while it was more responsive to ɑTOC treatment. Moreover, ɑTOC application significantly affected photosynthesis efficiency and plant water status as evaluated by relative water content and membrane stability index. These results were positively reflected in plant growth, productivity and water use efficiency under salt stress conditions, indicating that ɑTOC may participate in the enzymatic and non-enzymatic antioxidants. Therefore, foliar application of ɑTOC could be used to induce salt-tolerance in onion plants.

Soybean plants grown under NaCl were foliar sprayed twice with melatonin (MLT). Results revealed that salt stress reduced growth, biomass accumulation, photosynthesis, mineral uptake, the content of δ-aminolevulinic acid, chlorophylls, carotenoids and PSII efficiency. However, MLT application enhanced pigment synthesis and PSII activity. MLT up-regulated the antioxidant system and glyoxalase function resulting in reduced accumulation of reactive oxygen species (ROS). Reduced ROS in MLT-treated plants protected membrane functioning by reducing lipid peroxidation, electrolyte leakage and lipoxygenase activity. Nevertheless, MLT application reduced methylglyoxal accumulation while increased the content of reduced glutathione and ascorbic acid. It could be concluded that exogenous MLT mitigated the salt stress damage in soybean plants by improving photosynthesis, antioxidant systems, controlling ion homeostasis and minimising excessive ROS accumulation.  

The aim of the research was to test the effect of foliar-applied solutions of ascorbic acid (AsA), glycine betaine (GB), salicylic acid (SA) and water as a second control on the yield and seed germination of the soybean (Glycine hispida (Moench) Maxim.) cultivar 'Sava' as well as their influence on the content of N, P, K and Ca in soybean seeds, and to estimate the intensity of lipid peroxidation and free proline content in soybean seedlings. The plants were treated with the solutions twice. The 1 st spray treatment was done at growth stage 6: flowering (main shoot), when first flowers opened (sporadically in population), and the 2 nd spray treatment was done at growth stage 7: development of fruits and seeds, when the first pod had reached final length of 15-20 mm. Foliar application of the solutions had a significant impact on seed yield and seed germination in both years of the experiment. In a favourable year 2016, treatments with ascorbic acid, glycine betaine and salicylic acid solution significantly increased seed yield by 6.21-9.67%. However, in an unfavourable year 2017, the effect was significantly greater with the application of water (yield increase 6.48%), while the application of glycine betaine solution even reduced the seed yield. In a favourable year 2016, treatments with ascorbic acid and salicylic acid solution significantly increased seed germination by 7% and 8%, respectively. In an unfavourable year 2017, also only ascorbic acid and salicylic acid significantly increased seed germination by 11% and 9%, respectively. However, when using cold test, when the seed was exposed to a low temperature of 10°C for 7 days and then placed under optimal seed germination conditions for 4 days, ascorbic acid and glycine betaine solution reduced seed germination in both experimental years. Therefore, further research is needed on the methods designed to increase seed germination of soybean, both in favourable and adverse conditions in Serbia.

Soybean plants grown under NaCl were foliar sprayed twice with melatonin (MLT). Results revealed that salt stress reduced growth, biomass accumulation, photosynthesis, mineral uptake, the content of δ-aminolevulinic acid, chlorophylls, carotenoids and PSII efficiency. However, MLT application enhanced pigment synthesis and PSII activity. MLT up-regulated the antioxidant system and glyoxalase function resulting in reduced accumulation of reactive oxygen species (ROS). Reduced ROS in MLT-treated plants protected membrane functioning by reducing lipid peroxidation, electrolyte leakage and lipoxygenase activity. Nevertheless, MLT application reduced methylglyoxal accumulation while increased the content of reduced glutathione and ascorbic acid. It could be concluded that exogenous MLT mitigated the salt stress damage in soybean plants by improving photosynthesis, antioxidant systems, controlling ion homeostasis and minimising excessive ROS accumulation.  

Soybean plants grown under NaCl were foliar sprayed twice with melatonin (MLT). Results revealed that salt stress reduced growth, biomass accumulation, photosynthesis, mineral uptake, the content of δ-aminolevulinic acid, chlorophylls, carotenoids and PSII efficiency. However, MLT application enhanced pigment synthesis and PSII activity. MLT up-regulated the antioxidant system and glyoxalase function resulting in reduced accumulation of reactive oxygen species (ROS). Reduced ROS in MLT-treated plants protected membrane functioning by reducing lipid peroxidation, electrolyte leakage and lipoxygenase activity. Nevertheless, MLT application reduced methylglyoxal accumulation while increased the content of reduced glutathione and ascorbic acid. It could be concluded that exogenous MLT mitigated the salt stress damage in soybean plants by improving photosynthesis, antioxidant systems, controlling ion homeostasis and minimising excessive ROS accumulation.

Nitric oxide (NO) is a prevalent signaling molecule that regulates plant responses to potential plant stresses like drought. Growth and seed yield/plant improvement under drought stress resulted from the regulatory role of NO-priming on different physiological pathways of two faba bean plants differing in their drought tolerance. NO efficiently enhanced the machinery of photosynthesis via increasing chlorophyll a, b, and carotenoids associated with lowering hydrogen peroxide, superoxide anion, and hydroxyl radical. Thus, the tested dose of NO had an efficient free radical quenching system as witnessed from activating phenolics, ASA, SOD, APX, and CAT. These up-regulations reflected maintaining higher membrane stability via lowered lipid peroxidation and electrolyte leakage under control and drought-treated plants. The promoter role of NO on metabolic and antioxidative activities could serve as an essential component of the defense mechanism against oxidative burst induced by drought stress.     

Cite this as: Dief, N., Aldaby, E.S.E, Dawood, M.F.A., Zidan, M.A.A. (2019). Nitric oxide-mediated drought stresses tolerance via improvement crop yield, antioxidants, membrane integrity and reducing the oxidative stress of two faba bean cultivars. J. Multidiscip. Sci.1(2),1-11.

Drought stress is one of the most important stresses adversely affecting plant growth and yield production. Due
to the importance of global warming, the investigation of drought effects on the growth and quality of medical
plants is of vital importance. Accordingly, a two-year field experiment was conducted in 2013–2014 to determine
the effects of drought levels and plant species on Balangu (Lallemantia sp.) growth and physiological
properties including medicinal content. The experiment was a split plot in which the drought levels (main plots)
including control (D1, moisture field capacity, water potential at, 0.5 atm), moderate stress (D2, 6.5 atm) and
severe stress (D3, 9.5 atm), and the Balangu species (sub plots) including Lallemantia royleana (Benth) (L1) and L.
iberica (L2) were tested as the experimental treatments. Plant yield, oil content and the biochemical properties
(i.e. medicinal content) including phenolic compounds, proline, carotenoids, and the activity of antioxidant
enzymes including peroxidase (EC 1.11.1), super oxide dismutase (SOD, EC 1.15.1.1)) and ascorbate peroxidase
(APX, EC 1.11.1.11) were determined. Drought stress significantly decreased crop yield and oil content.
However, the production of phenolic compounds and proline as well as the activity of antioxidant enzymes, SOD
and APX increased under stress. The species L2 was the more tolerant species under drought stress. The interesting
point about this research work is the increased production of secondary metabolites (i.e. phenolic compounds)
under stress, affecting both Balangu response and medicinal properties. Accordingly, it may be possible
to regulate the production of secondary metabolites (medicinal contents) in Balangu species by adjusting the
irrigating practices.