scholarly journals Exogenous Melatonin Counteracts NaCl-Induced Damage by Regulating the Antioxidant System, Proline and Carbohydrates Metabolism in Tomato Seedlings

2019 ◽  
Vol 20 (2) ◽  
pp. 353 ◽  
Author(s):  
Manzer Siddiqui ◽  
Saud Alamri ◽  
Mutahhar Al-Khaishany ◽  
M. Khan ◽  
Abdullah Al-Amri ◽  
...  
Keyword(s):  
Plant Growth ◽  
Antioxidant System ◽  
Salt Content ◽  
Soluble Carbohydrates ◽  
Synthetase Activity ◽  
Enzymatic Antioxidants ◽  
Bisphosphate Carboxylase ◽  
Exogenous Melatonin ◽  
Chl A ◽  
Tomato Seedlings

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 and physio-biochemical parameters [chlorophyll (Chl) a and b, proline (Pro) and total soluble carbohydrates (TSC) content, and increased the activity of CA and Rubisco]. However, tomato seedlings treated with NaCl exhibited enhanced Chl degradation, electrolyte leakage (EL), malondialdehyde (MDA) and reactive oxygen species (ROS; superoxide and hydrogen peroxide). ROS were detected in leaf and root. Interestingly, application of melatonin improved plant growth and reduced EL, MDA and ROS levels through upregulation of photosynthesis enzymes (CA, Rubisco), antioxidant enzymes (superoxide dismutase, catalase, glutathione reductase and ascorbate reductase) and levels of non-enzymatic antioxidants [ascorbate (ASC) and reduced glutathione (GSH)], as well as by affecting the ASC—GSH cycle. Additionally, exogenous melatonin also improved osmoregulation by increasing the content of TSC, Pro and Δ1-pyrroline-5-carboxylate synthetase activity. These results suggest that melatonin has beneficial effects on tomato seedlings growth under both stress and non-stress conditions. Melatonin’s role in tolerance to salt stress may be associated with the regulation of enzymes involved in photosynthesis, the antioxidant system, metabolism of proline and carbohydrate, and the ASC—GSH cycle. Also, melatonin could be responsible for maintaining the high ratios of GSH/GSSG and ASC/DHA.

scholarly journals Exogenous Melatonin Modulates the Physiological and Biochemical Mechanisms of Drought Tolerance in Tartary Buckwheat (Fagopyrum tataricum (L.) Gaertn)

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2828
Author(s):  
Md. Shakhawat Hossain ◽  
Jing Li ◽  
Ashim Sikdar ◽  
Mirza Hasanuzzaman ◽  
Ferdinand Uzizerimana ◽  
...  
Keyword(s):  
Drought Stress ◽  
Plant Growth ◽  
Sugar Content ◽  
Soluble Sugar ◽  
Growth And Yield ◽  
Tartary Buckwheat ◽  
Arid Zones ◽  
Enzymatic Antioxidants ◽  
Fagopyrum Tataricum ◽  
Exogenous Melatonin

Tartary buckwheat is one of the nutritious minor cereals and is grown in high-cold mountainous areas of arid and semi-arid zones where drought is a common phenomenon, potentially reducing the growth and yield. Melatonin, which is an amphiphilic low molecular weight compound, has been proven to exert significant effects in plants, under abiotic stresses, but its role in the Tartary buckwheat under drought stress remains unexplored. We evaluated the influence of melatonin supplementation on plant morphology and different physiological activities, to enhance tolerance to posed drought stress by scavenging reactive oxygen species (ROS) and alleviating lipid peroxidation. Drought stress decreased the plant growth and biomass production compared to the control. Drought also decreased Chl a, b, and the Fv/Fm ratio by 54%, 70%, and 8%, respectively, which was associated with the disorganized stomatal properties. Under drought stress, H2O2, O2•−, and malondialdehyde (MDA) contents increased by 2.30, 2.43, and 2.22-folds, respectively, which caused oxidative stress. In contrast, proline and soluble sugar content were increased by 84% and 39%, respectively. However, exogenous melatonin (100 µM) could improve plant growth by preventing ROS-induced oxidative damage by increasing photosynthesis, enzymatic antioxidants (superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase), secondary metabolites like phenylalanine ammonialyase, phenolics, and flavonoids, total antioxidant scavenging (free radical DPPH scavenging), and maintaining relative water content and osmoregulation substances under water stress. Therefore, our study suggested that exogenous melatonin could accelerate drought resistance by enhancing photosynthesis and antioxidant defense in Tartary buckwheat plants.

scholarly journals Role of Ferrous Sulfate (FeSO4) in Resistance to Cadmium Stress in Two Rice (Oryza sativa L.) Genotypes

Biomolecules ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1693
Author(s):  
Javaria Afzal ◽  
Muhammad Hamzah Saleem ◽  
Fatima Batool ◽  
Ali Mohamed Elyamine ◽  
Muhammad Shoaib Rana ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Gas Exchange ◽  
Plant Growth ◽  
Photosynthetic Pigments ◽  
Ferrous Sulfate ◽  
Oryza Sativa L ◽  
Enzymatic Antioxidants ◽  
Cd Stress ◽  
Ultra Structure ◽  
Gas Exchange Characteristics

The impact of heavy metal, i.e., cadmium (Cd), on the growth, photosynthetic pigments, gas exchange characteristics, oxidative stress biomarkers, and antioxidants machinery (enzymatic and non-enzymatic antioxidants), ions uptake, organic acids exudation, and ultra-structure of membranous bounded organelles of two rice (Oryza sativa L.) genotypes (Shan 63 and Lu 9803) were investigated with and without the exogenous application of ferrous sulfate (FeSO4). Two O. sativa genotypes were grown under different levels of CdCl2 [0 (no Cd), 50 and 100 µM] and then treated with exogenously supplemented ferrous sulfate (FeSO4) [0 (no Fe), 50 and 100 µM] for 21 days. The results revealed that Cd stress significantly (p < 0.05) affected plant growth and biomass, photosynthetic pigments, gas exchange characteristics, affected antioxidant machinery, sugar contents, and ions uptake/accumulation, and destroy the ultra-structure of many membranous bounded organelles. The findings also showed that Cd toxicity induces oxidative stress biomarkers, i.e., malondialdehyde (MDA) contents, hydrogen peroxide (H2O2) initiation, and electrolyte leakage (%), which was also manifested by increasing the enzymatic antioxidants, i.e., superoxidase dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) and non-enzymatic antioxidant compounds (phenolics, flavonoids, ascorbic acid, and anthocyanin) and organic acids exudation pattern in both O. sativa genotypes. At the same time, the results also elucidated that the O. sativa genotypes Lu 9803 are more tolerant to Cd stress than Shan 63. Although, results also illustrated that the exogenous application of ferrous sulfate (FeSO4) also decreased Cd toxicity in both O. sativa genotypes by increasing antioxidant capacity and thus improved the plant growth and biomass, photosynthetic pigments, gas exchange characteristics, and decrease oxidative stress in the roots and shoots of O. sativa genotypes. Here, we conclude that the exogenous supplementation of FeSO4 under short-term exposure of Cd stress significantly improved plant growth and biomass, photosynthetic pigments, gas exchange characteristics, regulate antioxidant defense system, and essential nutrients uptake and maintained the ultra-structure of membranous bounded organelles in O. sativa genotypes.

scholarly journals Evaluation of Effect of Brassinolide in Brassica juncea Leaves under Drought Stress in Field Conditions

Horticulturae ◽  
2021 ◽  
Vol 7 (11) ◽  
pp. 514
Author(s):  
Naveen Naveen ◽  
Nisha Kumari ◽  
Ram Avtar ◽  
Minakshi Jattan ◽  
Sushil Ahlawat ◽  
...  
Keyword(s):  
Drought Stress ◽  
Brassica Juncea ◽  
Antioxidant System ◽  
Defense Mechanisms ◽  
Crop Improvement ◽  
Stress Conditions ◽  
Flower Initiation ◽  
Enzymatic Antioxidants ◽  
Stress Indicators ◽  
Enhanced Production

Drought stress is considered to be a major factor responsible for reduced agricultural productivity, because it is often linked to other major abiotic stresses, such as salinity and heat stress. Understanding drought-tolerance mechanisms is important for crop improvement. Moreover, under drought conditions, it is possible that growth regulators are able to protect the plants. Brassinosteroids not only play a regulatory role in plant growth, but also organize defense mechanisms against various tresses. This study aimed to evaluate the effect of brassinolide on physio-biochemical amendment in two contrasting cultivars (drought-tolerant RH 725, and drought-sensitive RH 749) of Brassica juncea under drought stress. Two foliar sprayings with brassinolide (10 and 20 mg/L) were carried out in both cultivars (RH 725 and RH 749) at two stages—i.e., flower initiation, and 50% flowering—under stress conditions. The results clearly revealed that the activities of antioxidative enzymes and non-enzymatic antioxidants (carotenoids, ascorbic acid, and proline) increased significantly in RH 725 at 50% flowering, whereas 20 mg/L of brassinolide showed the most promising response. The different oxidative stress indicators (i.e., hydrogen peroxide, malondialdehyde, and electrolyte leakage) decreased to a significant extent at 20 mg/L of brassinolide spray in RH 725 at 50% flowering. This study indicates that brassinolide intensifies the physio-biochemical attributes by improving the antioxidant system and photosynthetic efficiency in RH 725 at 50% flowering. It is assumed that enhanced production of proline, improvement of the antioxidant system, and reduction in the amount of stress indicators impart strength to the plants to combat the stress conditions.

scholarly journals CO2 Assimilation, Photosynthetic Enzymes, and Carbohydrates of `Concord' Grape Leaves in Response to Iron Supply

2004 ◽  
Vol 129 (5) ◽  
pp. 738-744 ◽  
Author(s):  
Li-Song Chen ◽  
Brandon R. Smith ◽  
Lailiang Cheng
Keyword(s):  
Sucrose Concentration ◽  
Calvin Cycle ◽  
Sucrose Phosphate Synthase ◽  
Nonstructural Carbohydrates ◽  
Bisphosphate Carboxylase ◽  
Chl A ◽  
Photosynthetic Enzymes ◽  
Fe Content ◽  
Significant Difference ◽  
Assimilation Capacity

Own-rooted 1-year-old `Concord' grapevines (Vitis labruscana Bailey) were fertigated twice weekly for 11 weeks with 1, 10, 20, 50, or 100 μm iron (Fe) from ferric ethylenediamine di (o-hydroxyphenylacetic) acid (Fe-EDDHA) in a complete nutrient solution. As Fe supply increased, leaf total Fe content did not show a significant change, whereas active Fe (extracted by 2,2′-dipyridyl) content increased curvilinearly. Chlorophyll (Chl) content increased as Fe supply increased, with a greater response at the lower Fe rates. Chl a: b ratio remained relatively constant over the range of Fe supply, except for a slight increase at the lowest Fe treatment. Both CO2 assimilation and stomatal conductance increased curvilinearly with increasing leaf active Fe, whereas intercellular CO2 concentrations decreased linearly. Activities of key enzymes in the Calvin cycle, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), NADP-glyceraldehyde-3-phosphate dehydrogenase (GAPDH), phosphoribulokinase (PRK), stromal fructose-1,6-bisphosphatase (FBPase), and a key enzyme in sucrose synthesis, cytosolic FBPase, all increased linearly with increasing leaf active Fe. No significant difference was found in the activities of ADP-glucose pyrophosphorylase (AGPase) and sucrose phosphate synthase (SPS) of leaves between the lowest and the highest Fe treatments, whereas slightly lower activities of AGPase and SPS were observed in the other three Fe treatments. Content of 3-phosphoglycerate (PGA) increased curvilinearly with increasing leaf active Fe, whereas glucose-6-phosphate (G6P), fructose-6-phosphate (F6P), and the ratio of G6P: F6P remained unchanged over the range of Fe supply. Concentrations of glucose, fructose, sucrose, starch, and total nonstructural carbohydrates (TNC) at both dusk and predawn increased with increasing leaf active Fe. Concentrations of starch and TNC at any given leaf active Fe content were higher at dusk than at predawn, but both glucose and fructose showed the opposite trend. No difference in sucrose concentration was found at dusk or predawn. The export of carbon from starch breakdown during the night, calculated as the difference between dusk and predawn measurements, increased as leaf active Fe content increased. The ratio of starch to sucrose at both dusk and predawn also increased with increasing leaf active Fe. In conclusion, Fe limitation reduces the activities of Rubisco and other photosynthetic enzymes, and hence CO2 assimilation capacity. Fe-deficient grapevines have lower concentrations of nonstructural carbohydrates in source leaves and, therefore, are source limited.

scholarly journals Fishwaste Compost Medium Improves Growth and Quality of Container-grown Marigolds and Geraniums Without Leaching

2000 ◽  
Vol 18 (2) ◽  
pp. 93-98 ◽  
Author(s):  
R.L. Hummel ◽  
S. Kuo ◽  
D. Winters ◽  
E.J. Jellum
Keyword(s):  
Plant Growth ◽  
Salt Content ◽  
Value Added ◽  
Growth Index ◽  
Dry Weight ◽  
Tagetes Patula ◽  
Greenhouse Production ◽  
Available N ◽  
N Source ◽  
Growing Medium

Abstract Utilization of fish waste for producing fishwaste compost (FWC) as a value-added product is preferred to disposing of it in ocean dumping or landfills. This study determined: (i) the effectiveness of FWC as a container-growth medium and N source for greenhouse production of marigolds (Tagetes patula L. ‘Queen Sophia’) and geraniums (Pelargonium x hortorum L.H. Bailey ‘Sprinter Scarlet’) that were drip-irrigated to prevent leaching; and (ii) if leaching was necessary to sustain plant growth. In a 3 by 3 factorial experiment, plants were grown in 100% FWC, 50% FWC:50% Douglas-fir bark (B), and 100% B at 0, 160, and 320 mg (0, 0.0056, 0.0112 oz) N container−1 applied as NH4NO3 every 2 weeks. Under drip irrigation, FWC in the 100% FWC growing medium supplied a sufficient amount of available N up to 7 weeks after transplanting to produce plant quality, shoot growth index (SGI), and shoot and root dry weights comparable to those treated with 320 mg N container−1. In the 50% FWC: 50% B growing medium fertilization with 320 mg N improved plant growth and quality 7 weeks after transplanting. The concentration of inorganic N (NO3 plus NH4) in the 100% FWC declined to very low levels 7 weeks after transplanting. This indicated that FWC used as the sole component of the growing medium was an effective N source for marigolds and geraniums up to 7 weeks after transplant. Compared with no leach plants, irrigation of 100% FWC marigolds with a weekly leaching fraction of about 0.55 did not affect quality, SGI, and shoot dry weight at the time-of-sale, 7 weeks after transplant. The FWC did not have sufficiently high salt content to require minimum leaching to prevent salt injury to the plants.

scholarly journals Effect of ascorbic acid on morphological and biochemical parameters in tomato seedling exposure to salt stress

2015 ◽  
Vol 26 (2) ◽  
pp. 21-25 ◽  
Author(s):  
Marcelina Krupa-Małkiewicz ◽  
Beata Smolik ◽  
Dominik Ostojski ◽  
Maja Sędzik ◽  
Justyna Pelc
Keyword(s):  
Ascorbic Acid ◽  
Salt Stress ◽  
Biochemical Parameters ◽  
Field Conditions ◽  
Tomato Seedling ◽  
Tomato Plants ◽  
Chl A ◽  
Tomato Seedlings ◽  
Root And Shoot Length ◽  
Mda Content

AbstractThe aim of this study is to determine the effect of both NaCl and KCl alone and in comparison to AsA on the morphological and some biochemical parameters of Oxheart and Vilma cultivars of tomato under laboratory and field conditions. A combination of salt applied in the laboratory experiment caused a significant effect on seed germination and root and shoot length and a significant reduction of Chl a, Chl b and Car contents in 14-day-old tomato seedlings. However, seedlings of cultivar Vilma were characterised by higher tolerance to applied salt stress.NaCl caused a significant decrease in Chl a, Chl b and Car, and an increase in Pro and MDA content in the leaves of Vilma cultivar under field conditions. Besides, tomato plants cv. Vilma treated with NaCl alone or NaCl with ascorbic acid developed longer roots, from 48 to 73%, compared to the control.

scholarly journals Ethylene Induction of Non-Enzymatic Metabolic Antioxidants in Matricaria chamomilla

Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5720
Author(s):  
Veronika Petrulova ◽  
Maria Vilkova ◽  
Zuzana Kovalikova ◽  
Matus Sajko ◽  
Miroslav Repcak
Keyword(s):  
Antioxidant System ◽  
Therapeutic Effects ◽  
Enzymatic Antioxidants ◽  
Matricaria Chamomilla ◽  
Chlorogenic Acids ◽  
Isolation And Identification ◽  
Phytochemical Content ◽  
Enzymatic Antioxidant ◽  
Dicaffeoylquinic Acid

Phytochemical investigations of Matricaria chamomilla L. (Asteraceae) stated the presence of several compounds with an established therapeutic and antioxidant potential. The chamomile non-enzymatic antioxidant system includes low molecular mass compounds, mainly polyphenols such as cinnamic, hydroxybenzoic and chlorogenic acids, flavonoids and coumarins. The objective of this work was to evaluate the role of the non-enzymatic antioxidant system after stimulation by ethylene in tetraploid chamomile plants. Seven days of ethylene treatment significantly increased the activity of phenylalanine ammonia-lyase, which influenced the biosynthesis of protective polyphenols in the first step of their biosynthetic pathway. Subsequently, considerable enhanced levels of phenolic metabolites with a substantial antioxidant effect (syringic, vanillic and caffeic acid, 1,5-dicaffeoylquinic acid, quercetin, luteolin, daphnin, and herniarin) were determined by HPLC-DAD-MS. The minimal information on the chlorogenic acids function in chamomile led to the isolation and identification of 5-O-feruloylquinic acid. It is accumulated during normal conditions, but after the excessive effect of abiotic stress, its level significantly decreases and levels of other caffeoylquinic acids enhance. Our results suggest that ethephon may act as a stimulant of the production of pharmaceutically important non-enzymatic antioxidants in chamomile leaves and thus, lead to an overall change in phytochemical content and therapeutic effects of chamomile plants, as well.

Metabolome adjustments in ectomycorrhizal Populus × canescens associated with strong promotion of plant growth by Paxillus involutus despite a very low root colonization rate

2020 ◽  
Vol 40 (12) ◽  
pp. 1726-1743
Author(s):  
Agnieszka Szuba ◽  
Łukasz Marczak ◽  
Izabela Ratajczak
Keyword(s):  
Plant Growth ◽  
Root Colonization ◽  
Growth Promotion ◽  
P Uptake ◽  
Soluble Carbohydrates ◽  
Paxillus Involutus ◽  
Root Tips ◽  
Poplar Trees ◽  
Related Proteins ◽  
Poplar Growth

Abstract It is believed that resource exchange, which is responsible for intensified growth of ectomycorrhizal plants, occurs in the fungus–plant interface. However, increasing evidence indicates that such intensified plant growth, especially root growth promotion, may be independent of root colonization. Nevertheless, the molecular adjustments in low-colonized plants remain poorly understood. Here, we analysed the metabolome of Populus × canescens microcuttings characterized by significantly increased growth triggered by inoculation with Paxillus involutus, which successfully colonized only 2.1 ± 0.3% of root tips. High-throughput metabolomic analyses of leaves, stems and roots of Populus × canescens microcuttings supplemented with leaf proteome data were performed to determine ectomycorrhiza-triggered changes in N-, P- and C-compounds. The molecular adjustments were relatively low in low-colonized (M) plants. Nevertheless, the levels of foliar phenolic compounds were significantly increased in M plants. Increases of total soluble carbohydrates, starch as well as P concentrations were also observed in M leaves along with the increased abundance of the majority of glycerophosphocholines detected in M roots. However, compared with the leaves of the non-inoculated controls, M leaves presented lower concentrations of both N and most photosynthesis-related proteins and all individual mono- and disaccharides. In M stems, only a few compounds with different abundances were detected, including a decrease in carbohydrates, which was also detected in M roots. Thus, these results suggest that the growth improvement of low-colonized poplar trees is independent of an increased photosynthesis rate, massively increased resource (C:N) exchange and delivery of most nutrients to leaves. The mechanism responsible for poplar growth promotion remains unknown but may be related to increased P uptake, subtle leaf pigment changes, the abundance of certain photosynthetic proteins, slight increases in stem and root amino acid levels and the increase in flavonoids (increasing the antioxidant capacity in poplar), all of which improve the fitness of low-colonized poplars.

Sign in / Sign up

Export Citation Format

Share Document