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1.
This study investigated the regulation of ascorbate and glutathione metabolism by nitric oxide in Agropyron cristatum leaves under water stress. The activities of ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate
reductase (MDHAR), dehydroascorbate reductase (DHAR), L-galactono-1,4-lactone dehydrogenase (GalLDH) and γ-glutamylcysteine
synthetase (γ-ECS), and the contents of NO, reduced ascorbic acid (AsA), reduced glutathione (GSH), total ascorbate and total
glutathione increased under water stress. These increases were suppressed by pretreatments with NO synthesis inhibitors N
G-nitro-L-arginine methyl ester (L-NAME) and 4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO). However,
application of L-NAME and cPTIO to plants sufficiently supplied with water did not affect the activities of above mentioned
enzymes and the contents of NO and above mentioned antioxidants. Pretreatments with L-NAME and cPTIO increased the malondialdehyde
(MDA) content and electrolyte leakage of plants under water stress. Our results suggested that water stress-induced NO is
a signal that leads to the upregulation of ascorbate and glutathione metabolism and has important role for acquisition of
water stress tolerance. 相似文献
2.
The activities of guaiacol peroxidase (GuPOD), ascorbate peroxidase (ASAp), superoxide dismutase (SOD) and ascorbate/glutathione cycle (AGC) enzymes, together with ascorbate (ASC) and glutathione contents, were determined in apoplastic-fluid and cell-wall fractions of needles of Pinus pinaster Ait. and Pinus radiata D. Don. exposed for up to 6 months to SO2 (0.01 ppm or 0.30 ppm) in fumigation chambers. AGC enzyme activities (monodehydroascorbate reductase, dehydroascorbate reductase and glutathione reductase) were in all cases undetectable, as was glutathione content. In needles of P. pinaster plants exposed to SO2, ascorbate content and all enzyme activities considered (except AGC enzymes) increased. The increases were most marked in response to the higher SO2 concentration. In needles of P. radiata, similar but less marked responses were observed. These findings suggest a) that enzyme activities and ascorbate contents increase in order to deal with the reactive oxygen intermediates produced during long-term contamination with SO2, and b) that P. pinaster has more effective defences against contamination of this type than P. radiata. 相似文献
3.
In the present study, we have investigated the effects of nitric oxide (NO) on alleviating manganese (Mn)-induced oxidative
stress in rice leaves. Exogenous MnCl2 treatment to excised rice leaves for 24 and 48 h resulted in increased production of H2O2 and lipid peroxides, decline in the levels of antioxidants, glutathione and ascorbic acid, and increased activities of antioxidative
enzymes, superoxide dismutase, guaiacol peroxidase, catalase, ascorbate peroxidase, dehydroascorbate reductase, and glutathione
reductase. Treatment of rice leaves with 100 μM sodium nitroprusside (SNP), a NO donor, was effective in reducing Mn-induced
increased levels of H2O2, lipid peroxides and increased activities of antioxidative enzymes. The levels of reduced ascorbate and glutathione were
considerably recovered due to SNP treatment. The effect of SNP was reversed by the addition of NO scavenger, 2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide
(c-PTIO) suggesting that ameliorating effect of SNP is due to release of NO. The results indicate that MnCl2 induces oxidative stress in excised rice leaves, lowers the levels of reduced ascorbate and glutathione, and elevates activities
of the key antioxidative enzymes. NO appears to provide a protection to the rice leaves against Mn-induced oxidative stress
and that exogenous NO application could be advantageous in combating the deleterious effects of Mn-toxicity in rice plants. 相似文献
4.
D. Talukdar 《Biologia Plantarum》2012,56(4):675-682
An ascorbate-deficient semi-dwarf mutant asfL-1 was detected in 250 Gy γ-ray treated grass pea (Lathyrus sativus L.) cv. BioR-231. The mutant contained only 42 % of leaf and 20 % of root ascorbate content of mother control (MC). I investigated the possible causes of ascorbate deficiency and its effect on growth and antioxidant defense in control and 150 mM NaCl-treated seedling after 60 d growth period. Ascorbate deficiency was due to significant reduction in activities of monodehydroascorbate reductase and dehydroascorbate reductase as well as increase in ascorbate oxidase, leading to considerable decrease in redox state. Despite low ascorbate pool and decrease in ascorbate peroxidase activity, shoot and root biomass production in asfL-1 mutant were similar to MC plants, even at NaCl treatment. High accumulation of glutathione (GSH) coupled with high activities of GSH reductase, catalase, GSH peroxidase and peroxidase in both tissues of the mutant permitted efficient recycling of GSH and scavenging of H2O2 through well integrated catalase/peroxidase system, despite high superoxide dismutase activity under NaCl treatment. The collapse of this system led to inhibition of growth in NaCl-treated mother plants. Together, the results suggested that asfL-1 plants undertook a major reshuffle in its antioxidant defense machinery, which effectively counterbalanced the negative impact of ascorbate deficiency and remained unperturbed by NaCl treatment to maintain normal growth and biomass production. 相似文献
5.
Luigi Sanit di Toppi Rosita Marabottini Maurizio Badiani Antonio Raschi 《Journal of plant physiology》2002,159(9)
Here we present studies on the antioxidant status of a semi-natural grassland community, permanently growing in mini-FACE rings under elevated concentrations of atmospheric CO2 (560 μmol mol−1). In general, in leaves of Dactylis glomerata L. and Trifolium repens L., no differences between ambient and elevated CO2 were detected as concerns protein content, activity of oxidant-scavenging enzymes (catalase, superoxide dismutase, ascorbate peroxidase and guaiacol peroxidase), and lipid peroxidation. The activity of antioxidant-regenerating enzymes (monodehydroascorbate reductase, dehydroascorbate reductase and glutathione disulfide reductase) and the content of antioxidants (ascorbic acid, dehydroascorbic acid, reduced glutathione and glutathione disulfide) showed remarkable variability between leaves from plants grown in ambient and CO2-enriched mini-FACE rings. Thus, in general it can be concluded that the effects of elevated CO2 at environmentally relevant concentrations on the leaf antioxidant status of a grassland community are extremely variable, species-specific and rather limited. 相似文献
6.
Nitric oxide modulates antioxidant defense and the methylglyoxal detoxification system and reduces salinity-induced damage of wheat seedlings 总被引:2,自引:0,他引:2
Mirza Hasanuzzaman Mohammad Anwar Hossain Masayuki Fujita 《Plant biotechnology reports》2011,5(4):353-365
The present study investigates the possible regulatory role of exogenous nitric oxide (NO) in antioxidant defense and methylglyoxal
(MG) detoxification systems of wheat seedlings exposed to salt stress (150 and 300 mM NaCl, 4 days). Seedlings were pre-treated
for 24 h with 1 mM sodium nitroprusside, a NO donor, and then subjected to salt stress. The ascorbate (AsA) content decreased
significantly with increased salt stress. The amount of reduced glutathione (GSH) and glutathione disulfide (GSSG) and the
GSH/GSSG ratio increased with an increase in the level of salt stress. The glutathione S-transferase (GST) activity increased significantly with severe salt stress (300 mM). The ascorbate peroxidase (APX), monodehydroascorbate
reductase (MDHAR), dehydroascorbate reductase (DHAR), catalase (CAT) and glutathione peroxidase (GPX) activities did not show
significant changes in response to salt stress. The glutathione reductase (GR), glyoxalase I (Gly I), and glyoxalase II (Gly
II) activities decreased upon the imposition of salt stress, especially at 300 mM NaCl, with a concomitant increase in the
H2O2 and lipid peroxidation levels. Exogenous NO pre-treatment of the seedlings had little influence on the non-enzymatic and
enzymatic components compared to the seedlings of the untreated control. Further investigation revealed that NO pre-treatment
had a synergistic effect; that is, the pre-treatment increased the AsA and GSH content and the GSH/GSSG ratio, as well as
the activities of MDHAR, DHAR, GR, GST, GPX, Gly I, and Gly II in most of the seedlings subjected to salt stress. These results
suggest that the exogenous application of NO rendered the plants more tolerant to salinity-induced oxidative damage by enhancing
their antioxidant defense and MG detoxification systems. 相似文献
7.
Drought Induces Oxidative Stress and Enhances the Activities of Antioxidant Enzymes in Growing Rice Seedlings 总被引:7,自引:0,他引:7
When rice seedlings grown for 10 and 20 days were subjected to in vitro drought stress of −0.5 and −2.0 MPa for 24 h, an increase in the concentration of superoxide anion (O2.−), increased level of lipid peroxidation and a decrease in the concentration of total soluble protein and thiols was observed
in stressed seedlings compared to controls. The concentration of H2O2 as well as ascorbic acid declined with imposition of drought stress, however glutathione (GSH) concentration declined only
under severe drought stress. The activities of total superoxide dismutases (SODs) as well as ascorbate peroxidase (APX) showed
consistent increases with increasing levels of drought stress, however catalase activity declined. Mild drought stressed plants
had higher guaiacol peroxidase (GPX) and chloroplastic ascorbate peroxidase (c-APX) activity than control grown plants but
the activity declined at the higher level of drought stress. The activities of enzymes involved in regeneration of ascorbate
i.e. monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) were higher
in drought stressed plants compared to controls. Results suggest that drought stress induces oxidative stress in rice plants
and that besides SOD, the enzymes of ascorbate-glutathione cycle, which have not been studied in detail earlier under stressful
conditions, appear to function as important component of antioxidative defense system under drought stress. 相似文献
8.
The effects of methyl jasmonate (MJ) and salicylic acid (SA) on changes of the activities of major antioxidant enzymes, superoxide anion accumulation (O2
−), ascorbate, total glutathione (TG), malondialdehyde (MDA) content and ginsenoside accumulation were investigated in ginseng roots (Panax ginseng L.) in 4 l (working volume) air lift bioreactors. Single treatment of 200 μM MJ and SA to P. ginseng roots enhanced ginsenoside accumulation compared to the control and harvested 3, 5, 7 and 9 days after treatment. MJ and SA treatment induced an oxidative stress in P. ginseng roots, as shown by an increase in lipid peroxidation due to rise in O2
− accumulation. Activity of superoxide dismutase (SOD) was inhibited in MJ-treated roots, while the activities of monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), SOD, guaiacol peroxidase (G-POD), glutathione peroxidase (GPx) and glutathione reductase (GR) were induced in SA-treated roots. A strong decrease in the activity of catalase (CAT) was obtained in both MJ- and SA-treated roots. Activities of ascorbate peroxidase (APX) and glutathione S transferase (GST) were higher in MJ than SA while the contents of reduced ascorbate (ASC), redox state (ASC/(ASC+DHA)) and TG were higher in SA- than MJ-treated roots while oxidized ascorbate (DHA) decreased in both cases. The result of these analyses suggests that roots are better protected against the O2
− stress, thus mitigating MJ and SA stress. The information obtained in this work is useful for efficient large-scale production of ginsenoside by plant-root cultures. 相似文献
9.
Effects of exogenous salicylic acid (SA) on plant growth, contents of Na, K, Ca and Mg, activities of superoxide dismutase
(SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR)
and catalase (CAT), and contents of ascorbate and glutathione were investigated in tomato (Lycopersicon esculentum L.) plants treated with 100 mM NaCl. NaCl treatment significantly increased H2O2 content and lipid peroxidation indicated by accumulation of thiobarbituric acid reactive substances (TBARS). A foliar spray
of 1 mM SA significantly decreased lipid peroxidation caused by NaCl and improved the plant growth. This alleviation of NaCl
toxicity by SA was related to decreases in Na contents, increases in K and Mg contents in shoots and roots, and increases
in the activities of SOD, CAT, GPX and DHAR and the contents of ascorbate and glutathione. 相似文献
10.
Shunhua Ding Qingtao Lu Yan Zhang Zhipan Yang Xiaogang Wen Lixin Zhang Congming Lu 《Plant molecular biology》2009,69(5):577-592
To investigate the possible mechanisms of glutathione reductase (GR) in protecting against oxidative stress, we obtained transgenic
tobacco (Nicotiana tabacum) plants with 30–70% decreased GR activity by using a gene encoding tobacco chloroplastic GR for the RNAi construct. We investigated
the responses of wild type and transgenic plants to oxidative stress induced by application of methyl viologen in vivo. Analyses
of CO2 assimilation, maximal efficiency of photosystem II photochemistry, leaf bleaching, and oxidative damage to lipids demonstrated
that transgenic plants exhibited enhanced sensitivity to oxidative stress. Under oxidative stress, there was a greater decrease
in reduced to oxidized glutathione ratio but a greater increase in reduced glutathione in transgenic plants than in wild type
plants. In addition, transgenic plants showed a greater decrease in reduced ascorbate and reduced to oxidized ascorbate ratio
than wild type plants. However, there were neither differences in the levels of NADP and NADPH and in the total foliar activities
of monodehydroascorbate reductase and dehydroascorbate reductase between wild type and transgenic plant. MV treatment induced
an increase in the activities of GR, ascorbate peroxidase, superoxide dismutase, and catalase. Furthermore, accumulation of
H2O2 in chloroplasts was observed in transgenic plants but not in wild type plants. Our results suggest that capacity for regeneration
of glutathione by GR plays an important role in protecting against oxidative stress by maintaining ascorbate pool and ascorbate
redox state. 相似文献
11.
《Journal of Plant Interactions》2013,8(2):140-154
The study highlights the role of sulfur (S) in detoxification of arsenate-induced toxicity and the shift in essential element homeostasis in Zea mays L (SRHM 445). Overall growth of arsenate-treated plants under sulfur starvation (?S) was lower than that in the presence of excess sulfur (+S). Translocation of arsenate from roots to shoots, increased under As(?S) and decreased with As(+S). The level of micronutrients (Cu, Zn, Fe) increased in As(?S) plants. Whereas, the level of K and PO4 was higher in As(?S) plants than in As(+S) plants. Higher malondialdehyde, protein carbonyl, and H2O2 levels in As(?S) plants are indicative of higher oxidative stress. Higher superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities, in As(?S) plants coincided with higher H2O2 levels showing the activity of these enzymes are independent of S availability. Absence of reduced glutathione/oxidized glutathione pool in (?S) plants manifested into failure of ascorbate–glutathione detoxification pathway. Hence, S has dual role of protecting the plant against arsenate-induced toxicity (1) by restricting arsenic (As) translocation to the upper parts and (2) by increasing the activity SOD and APX. 相似文献
12.
María C. Martí Igor Florez‐Sarasa Daymi Camejo Beatriz Pallol Ana Ortiz Miquel Ribas‐Carbó Ana Jiménez Francisca Sevilla 《Physiologia plantarum》2013,147(2):194-206
Nitric oxide (NO) has emerged as an important signaling molecule in plants, but little is known about the effects of reactive nitrogen species in plant mitochondria. In this study, the effects of DETA‐NONOate, a pure NO slow generator, and of SIN‐1 (3‐morpholinosydnonimine), a peroxynitrite producer, on the activities of respiratory pathways, enzymatic and non‐enzymatic antioxidants have been investigated in isolated mitochondria from pea leaves. No significant changes in lipid peroxidation, protein oxidation or in ascorbate and glutathione redox state were observed after DETA‐NONOate treatments whereas cytochrome pathway (CP) respiration was reversibly inhibited and alternative pathway (AP) respiration showed little inhibition. On the other hand, NO did not affect neither activities of Mn superoxide dismutase (Mn‐SOD) nor enzymes involved in the ascorbate and glutathione regeneration in mitochondria except for ascorbate peroxidase (APX), which was reversely inhibited depending on ascorbate concentration. Finally, SIN‐1 treatment of mitochondria produced a decrease in CP respiration, an increase in protein oxidation and strongly inhibited APX activity (90%), with glutathione reductase and dehydroascorbate reductase (DHAR) being moderately inhibited (30 and 20%, respectively). This treatment did not affect monodehydroascorbate reductase (MDHAR) and Mn‐SOD activities. Results showed that mitochondrial nitrosative stress was not necessarily accompanied by oxidative stress. We suggest that NO‐resistant AP and mitochondrial APX may be important components of the H2O2‐signaling pathways under nitrosative stress induced by NO in this organelle. Also, MDHAR and DHAR, via ascorbate regeneration, could constitute an essential antioxidant defense together with Mn‐SOD, against NO and ONOO? stress in plant mitochondria. 相似文献
13.
Indian mustard (Brassica juncea L. cv. Vitasso) plants exposed to 10, 30, 50 and 100 μM of Cd for 5 d in hydroponic culture were analysed with reference
to the distribution of Cd2+, the accumulation of biomass and antioxidants and antioxidative enzymes in leaves. Cd induced a decrease in plant biomass.
The maximum accumulation of Cd occurred in roots followed by stems and leaves. Cd induced a decrease in catalase (CAT) and
guiacol peroxidase (GPX) activities but an increase in ascorbate peroxidase (APX) and monodehydroascorbate reductase (MDHAR)
activities. Enhancement in dehydroascorbate reductase (DHAR) activity was also at 10 μM Cd. Glutathione reductase (GR) activity
showed pronounced stimulation after all treatments, but glutathione S-transferase (GST) and glutathione peroxidase (GPOX)
activities decreased. The effectiveness of ascorbate-glutathione cycle (AGC) was determined by the ratio of ascorbate to H2O2. This ratio decreased in the Cd-treated leaves which indicated that the cycle was disordered. 相似文献
14.
Effects of ambient oxygen and of fixed nitrogen on concentrations of glutathione, ascrobate, and associated enzymes in soybean root nodules 总被引:4,自引:3,他引:1
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Soybean (Glycine max [L.] Merr.) root nodules contain the enzymes of the ascorbate-glutathione cycle for defense against activated forms of oxygen. Nodulated roots of hydroponically grown soybean plants were exposed to atmospheres containing 2, 21, 50, or alternating 21 and 50 kilopascals of O2. The activities of ascorbate (ASC) peroxidase, monodehydroascorbate (MDHA) reductase, dehydroascorbate (DHA) reductase, and glutathione (GSSG) reductase were higher in nodules exposed to high pO2. Nodule contents of ascorbate and reduced glutathione were also greater in the high pO2 treatments. Treatment of nodulated plants with fixed nitrogen (urea) led to concomitant decreases in acetylene reduction activity, in leghemoglobin content, and in activities of ASC peroxidase, DHA reductase, and GSSG reductase. Activity of MDHA reductase and glutathione concentrations in nodules were not affected by treatment with urea. The enzymes of the ascorbate-glutathione cycle were also detected in uninfected soybean roots, although at levels substantially below those in nodules. These observations indicate that the ascorbate-glutathione cycle can adjust to varying physiological conditions in nodules and that there is a key link between N2 fixation and defenses against activated forms of oxygen. 相似文献
15.
Vitrification of shoots of Prunus avium L. L. was induced and expressed in a four week in vitro multiplication cycle simply by replacing agar by gelrite. The first vitrification symptoms were visible from the 7th day on. Enzymatic antioxidants were compared weekly in crude extract of normal (on agar) and vitrifying (on gelrite) shoots. The activity of superoxide dismutase was higher in vitrifying shoots. The other enzymes (gaîacol-peroxidase, catalase, ascorbate peroxidase, mono- and dehydro-ascorbate reductases, glutathione reductase) had lower activities. Increased superoxide dismutase activity might mean hydrogen peroxide accumulation and decreased activities of the other enzymes, deficiency in its detoxification. The question therefore is raised whether the hyperhydric morphological abnormalities result from the accumulation of toxic oxygen forms. Vitrification is often considered as a morphological response to several stresses. Contrary to most plants which adapt themselves to stresses by increasing all the above defence enzymes, in vitro shoots under vitrifying conditions appear unable to react in a similar manner.Abbreviations Apx
ascorbate peroxidase
- Gpx
gaîacol peroxidase
- CAT
catalase
- H2O2
hydrogen peroxide
- SOD
superoxide dismutase
- MDHAR
monodehydroascorbate reductase
- DHAR
dehydroascorbate reductase
- GR
glutathione reductase
- MS
Murashige and Skoog (1962)
- IBA
indolebutyric acid
- BAP
benzyladenine
- GA3
gibberellic acid 相似文献
16.
The relationships between drought response and anatomical/physiological properties were assessed in two poplar clones belonging
to the Aigeros section: Populusxeuramericana clone Dorskamp (drought-tolerant) and clone Luisa Avanzo (drought-sensitive). Cuttings of both clones were exposed for 12
h to 0 mM (control). 50 mM (osmotic potential −0.112 MPa), and 150 mM (−0.336 MPa) mannitol. In control, Dorskamp had smaller
stomata than Luisa Avanzo, one or two layers of palisade cells, a spongy mesophyll, and high concentrations of antioxidative
compounds (ascorbate, glutathione). After exposure to 50 or 150 mM mannitol, both clones closed their stomata: leaf conductance
and opening of stomata decreased. When exposed to 50 mM mannitol, net photosynthetic rate (P
N) and chlorophyll (Chl) and total solute contents remained stable; ribulose-1,5-bisphosphate carboxylase/-oxygenase activity,
Chl synthesis and turn-over, ascorbate peroxidase and glutathione reductase activities were less affected in Dorskamp than
in Luisa Avanzo. Following an exposure to 150 mM mannitol, Dorskamp exhibited higher P
N and higher contents of antioxidants (ascorbate, glutathione) and antioxidative enzymes (ascorbate peroxidase, glutathione
reductase) than Luisa Avanzo. Hence the drought-tolerant poplar was able to better avoid and tolerate osmotic stress.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
17.
Antioxidant defences of the apoplast 总被引:1,自引:0,他引:1
Summary The apoplast of barley and oat leaves contained superoxide dismutase (SOD), catalase, ascorbate peroxidase, dehydroascorbate reductase, monodehydroascorbate reductase, and glutathione reductase activities. The activities of these enzymes in the apoplastic extracts were greatly modified 24 h after inoculation with the biotrophic fungal pathogenBlumeria graminis. The quantum efficiency of photosystem II, which is related to photosynthetic electron transport flux, was comparable in inoculated and healthy leaves during this period. Apoplastic soluble acid invertase activity was also modified in inoculated leaves. Inoculation-dependent increases in apoplastic SOD activity were observed in all lines. Major bands of SOD activity, observed in apoplastic protein extracts by activity staining of gels following isoelectric focusing, were similar to those observed in whole leaves but two additional minor bands were found in the apoplastic fraction. The apoplastic extracts contained substantial amounts of dehydroascorbate (DHA) but little or no glutathione (GSH). Biotic stress decreased apoplastic ascorbate and DHA but increased apoplastic GSH in resistant lines. The antioxidant cycle enzymes may function to remove apoplastic H2O2 with ascorbate and GSH derived from the cytoplasm. DHA and oxidized glutathione may be reduced in the apoplast or returned to the cytosol for rereduction.Abbreviations AA
reduced ascorbate
- APX
ascorbate peroxidase
- DHA
dehydroascorbate (oxidised ascorbate)
- DHAR
dehydroascorbate reductase
- G6PDH
glucose-6-phosphate dehydrogenase
- GSH
reduced glutathione
- GSSG
glutathione disulphide
- GR
glutathione reductase
- MDHA
monodehydroascorbate
- MDHAR
monodehydroascorbate reductase
- SOD
superoxide dismutase 相似文献
18.
Hydrogen peroxide-scavenging enzymes and antioxidants in Echinochloa frumentacea as affected by triazole growth regulators 总被引:2,自引:0,他引:2
Paclobutrazol (PBZ)- and uniconazole (UCZ)-treated plants of Echinochloa frumentacea were shorter but had much wider leaves than untreated controls 10 days after treatment. Leaves of treated plants had a slightly higher concentration of soluble protein than the controls and exhibited enhanced activities of ascorbate peroxidase, monodehydroascorbate (MDHA) reductase, and glutathione (GSH) reductase. The triazoles did not influence the activity of dehydroascorbate (DHA) reductase. The leaves of treated plants had increased concentrations of water-soluble sulfhydryls and ascorbic acid. In contrast, the concentration of malondialdehyde (MDA), a by-product of lipid peroxidation, was lower in the leaves of treated plants than in controls. These results suggest that triazole growth regulators increased the activity of the endogenous H2O2-scavenging system in E. frumentacea. 相似文献
19.
Sunita Sheokand Anita Kumari Veena Sawhney 《Physiology and Molecular Biology of Plants》2008,14(4):355-362
Chickpea plants were subjected to salt stress for 48 h with 100 mM NaCl, after 50 days of growth. Other batches of plants were simultaneously treated with 0.2 mM sodium nitroprusside (NO donor) or 0.5 mM putrescine (polyamine) to examine their antioxidant effects. Sodium chloride stress adversely affected the relative water content (RWC), electrolyte leakage and lipid peroxidation in leaves. Sodium nitroprusside and putrescine could completely ameliorate the toxic effects of salt stress on electrolyte leakage and lipid peroxidation and partially on RWC. No significant decline in chlorophyll content under salt stress as well as with other treatments was observed. Sodium chloride stress activated the antioxidant defense system by increasing the activities of peroxidase (POX), catalase (CAT) superoxide dismutase (SOD) and ascorbate peroxidase (APX). However no significant effect was observed on glutathione reductase (GR) and dehydro ascorbate reductase (DHAR) activities. Both putrescine and NO had a positive effect on antioxidant enzymes under salt stress. Putrescine was more effective in scavenging superoxide radical as it increased the SOD activity under salt stress whereas nitric oxide was effective in hydrolyzing H2O2 by increasing the activities of CAT, POX and APX under salt stress. 相似文献
20.
Changes in the Activity of Antioxidant Enzymes in Wheat Leaves and Roots as a Function of Nitrogen Source and Supply 总被引:3,自引:0,他引:3
Polesskaya O. G. Kashirina E. I. Alekhina N. D. 《Russian Journal of Plant Physiology》2004,51(5):615-620
The activity of enzymes participating in the systems of antioxidant protection was assayed in the second leaf and roots of 21-day-old wheat seedlings (Triticum aestivum L.) grown in a medium with nitrate (NO–
3 treatment), ammonium (NH+
4 treatment), or without nitrogen added (N-deficiency treatment). The activities of superoxide dismutase (SOD), peroxidase, ascorbate peroxidase, glutathione reductase, and catalase in the leaves and roots of the NH+
4 plants was significantly higher than in the plants grown in the nitrate medium. The activity of SOD decreased and ascorbate peroxidase markedly increased in leaves, whereas the activity of ascorbate peroxidase increased in the roots of N-deficient plants, as compared to the plants grown in nitrate and ammonium. Low-temperature incubation (5°, 12 h) differentially affected the antioxidant activity of the studied plants. Whereas leaf enzyme activities did not change in the NH+
4 plants, the activities of SOD, peroxidase, ascorbate peroxidase, and catalase markedly increased in the NO–
3 plants. In leaves of the N-deficient plant, the activity of SOD decreased; however, the activity of other enzymes increased. In response to temperature decrease, catalase activity increased in the roots of NO–
3 and NH+
4-plants, whereas in the N-deficient plants, the activity of peroxidase increased. Thus, in wheat, both nitrogen form and nitrogen deficiency changed the time-course of antioxidant enzyme activities in response to low temperature. 相似文献