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1.
Wheat (Triticum aestivum L. cv. ‘Zyta’) seedlings were treated with 10, 100 and 200 μM Ni. Tissue Ni accumulation, length, relative water content
(RWC), proline and H2O2 concentrations as well as the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), guaiacol
peroxidase (POD) and glutathione S-transferase (GST) were studied in the shoots and roots after 6 days of Ni exposure. Treatment
with Ni, except for its lowest concentration, resulted in a significant reduction in wheat growth. In comparison to the shoots,
the roots showed greater inhibition of elongation, which corresponded with higher accumulation of Ni in these organs. Both
shoots and roots responded to Ni application with a decrease in RWC and enhancement in proline concentration. Greater dehydration
of the shoot tissue was accompanied by more intense accumulation of proline. Treatment of the wheat seedlings with the highest
concentration of Ni led to about 60% increase in H2O2 concentration in both studied organs. Apart from CAT, constitutive activities of antioxidative enzymes were much higher in
the roots than in the shoots. Exposure of the seedlings to Ni resulted in SOD activity decline, which was more marked in the
roots. While the shoots showed a substantial decrease (up to 30%) in CAT activity, in the roots the activity of this enzyme
remained unchanged. After Ni application APX, POD and GST activities increased several-fold in the shoots, whereas in the
roots they were not significantly altered. The results suggest that differential antioxidative responses of the shoots and
roots of wheat seedlings to Ni stress might be related to diverse constitutive levels of antioxidant enzyme activities in
both organs. 相似文献
2.
Influence of 100 μM Ni on growth, Ni accumulation,, H2O2 and lipid peroxides contents as well as the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase
(APX), guaiacol peroxidase (POD) and glutathione peroxidase (GSH-Px) were studied in the leaves of wheat plants on the 3rd,
6th and 9th days after treatment. Exposure of the plants to Ni for only 3 days led to almost 200-fold increase in this metal
concentration in the leaf tissue but later the rate of Ni accumulation was much slower. Length and fresh weight of the leaves
were substantially reduced, up to 25% and 39%, respectively at the end of experiment. Visible symptoms of Ni toxicity: chlorosis
and necrosis were observed following the 3rd day. Treatment with Ni resulted in the increase in and H2O2 contents in the leaves. Both showed their highest values, approximately 250% of those of the control, on the 3rd day and
then their levels decreased but still markedly exceeded the control values. SOD and CAT activities decreased significantly
in response to Ni treatment, however a several-fold increase in APX and POD activities was found. No significant changes in
lipid peroxides content were observed in the leaves after Ni application. The activity of GSH-Px showed a 29% induction on
the 3rd day. Our results indicated that despite prolonged increases in and H2O2 levels, oxidative damage, measured as the level of lipid peroxidation, did not occur in the leaves of Ni-treated wheat. 相似文献
3.
Quantitative trait loci (QTLs) for Cu-tolerance were determined in wheat grown in control and Cu-treated soil in greenhouse.
In addition, loci having an influence on the shoot Cu-, Fe-, Mn-and Zn-contents under non-stressed and Cu-stressed environments
were mapped. One major QTL for Cu-tolerance was found on chromosome 5DL, while slighter effects were determined on the chromosomes
1AL, 2DS, 4AL, 5BL and 7DS. QTLs affecting the shoot Mn-and Zn-contents were found on the chromosomes 3BL and 3AL, respectively.
The centromeric region on the chromosome 3B plays a role in the regulation of the shoot Fe-contents in the stressed plants.
Under Cu-stress QTL affecting shoot Cu-content was found on chromosome 1BL, while on the chromosome 5AL a QTL influencing
the Cu-accumulation ability of wheat from Cu-polluted soil was determined. 相似文献
4.
Sami Ahmad Chris A. Pritsos Ronald S. Pardini 《Archives of insect biochemistry and physiology》1990,15(2):101-109
The black swallowtail butterfly, Papilio polyxenes, larvae are specialized feeders of pro-oxidant rich plants of Apiaceae and Rutaceae. An important defense against toxic forms of oxygen species generated by ingestion of the pro-oxidants, are the antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), GSH-dependent glutathione peroxidases (selenium-dependent glutathione peroxidase [GPOX] and peroxidase activity of selenium-independent glutathione-S-transferase [GTpx]), and glutathione reductase (GR). The subcellular distribution of these enzymes in black swallowtail larvae was investigated and was found to resemble the patterns described for larvae of two other lepidopteran species: the southern armyworm, Spodoptera eridania, and the cabbage looper, Trichoplusia ni. The confinement of SOD in the cytosol and mitochondria was typically eukaryotic, but the relative proportion (1:1) was markedly different from the mammalian pattern (4:1; cytosol:mitochondria). The most obvious difference between the black swallowtail and other lepidoptera as a group, and mammalian species, is in very wide intracellular distributions of CAT, GTpx, and GR in insect species. Insects possess very low levels of a GPOX-like activity which reduces both H2O2 and organic peroxides. Consequently, insects have elaborate activities with a wide subcellular distribution of both CAT which decomposes H2O2, and GTpx which decomposes organic peroxides. The reduction of peroxides is dependent on GSH, which in this process is oxidized to GSSG. GR which reduces GSSG to GSH is also of wide subcellular distribution, analogous to the distribution pattern of GTpx. 相似文献
5.
Effects of flooding on the activities of some enzymes of activated oxygen metabolism, the levels of antioxidants, and lipid peroxidation in senescing leaves of tobacco were investigated. As judged by the decrease in chlorophyll and protein levels, flooding accelerated the senescence of tobacco leaves. Total peroxide and the lipid peroxidation product, malondialdehyde, increased in both control and flooding-treated leaves with increasing duration of the experiment. Throughout the duration of the experiment, flooded leaves had higher levels of total peroxide and malondialdehyde than did control leaves. Flooding resulted in an increase in peroxidase and ascorbate peroxidase activities and a reduction of superoxide dismutase activity in the senescing leaves. Glycolate oxidase, catalase, and glutathione reductase activities were not affected by flooding. Flooding increased the levels of total ascorbate and dehydroascorbate. Total glutathione, reduced form glutathione, or oxidized glutathione levels in flooded leaves were lower than in control leaves during the first two days of the experiment, but were higher than in control leaves at the later stage of the experiment. Our work suggests that senescence of tobacco induced by flooding may be a consequence of lipid peroxidation possibly controlled by superoxide dismutase activity. Our results also suggest that increased rates of hydrogen peroxide in leaves of flooded plants could lead to increased capacities of the scavenging system of hydrogen peroxide.Abbreviations GSH
reduced form glutathione
- GSSG
oxidized form glutathione
- GSSG reductase
glutathione reductase
- MDA
malondialdehyde
- SOD
superoxide dismutase 相似文献
6.
Changes in antioxidant enzymes activity and oxidative stress by abscisic acid and salicylic acid in wheat genotypes 总被引:9,自引:0,他引:9
Abscisic acid (ABA) and salicylic acid (SA) were sprayed on leaves of wheat genotypes C 306 and Hira at 25 and 40 d after sowing under moderate water stress (−0.8 MPa) imposed by adding PEG-6000 in nutrient solution. ABA and SA increased the activities of superoxide dismutase, ascorbate peroxidase, glutathione reductase, and catalase in comparison to unsprayed control plants. Both ABA and SA treatments decreased the contents of hydrogen peroxide and thiobarbituric acid reactive substances, a measure of lipid peroxidation, compared to unsprayed plants. The beneficial effect of increase in antioxidant enzymes activity and decrease in oxidative stress was reflected in increase in chlorophyll and carotenoid contents, relative water content, membrane stability index, leaf area and total biomass over control plants. The lower concentrations of ABA (0.5 mM) and SA (1.0 mM) were generally more effective than higher concentrations. 相似文献
7.
The present study was carried out to study the effect of salt stress on cell membrane damage, ion content and antioxidant
enzymes in wheat (Triticum aestivum) seedlings of two cultivars salt-tolerant KRL-19 and salt-sensitive WH-542. Seedlings (4-d-old) were irrigated with 0, 50
and 100 mM NaCl. Observations were recorded on the 3rd and 6th day after salt treatment and 2nd day after salt removal. The relative water content declined with induction of salt stress, more in WH-542 than in cv. KRL-19.
K+/Na+ ratio in KRL-19 was higher than in WH-542. WH-542 suffered greater damage to cellular membranes due to lipid peroxidation
as indicated by higher accumulation of H2O2, MDA and greater leakage of electrolytes than KRL-19. The activities of catalase, peroxidase and ascorbate peroxidase and
glutathione reductase increased with increase in salt stress in both the cultivars, however, superoxide dismutase activity
declined. Upon desalanization, partial recovery in the activities of these enzymes was observed in KRL-19 and very slow recovery
in WH-542. 相似文献
8.
We tested the mode of action of Cd on photosynthesis and activities of ATP-sulfurylase (ATP-S), catalase (CAT), superoxide
dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR), and on contents of phytochelatins (PCs) and glutathione
(GSH) in two cultivars of wheat (Triticum aestivum L.) PBW-343 and WH-542 differing in yield potential. Cd treatment increased Cd content and photosynthetic activity in PBW-343
more than in WH-542. The activities of APX, GR, ATP-S, and synthesis of PCs and GSH were also increased by Cd, but the CAT
and SOD activities were inhibited in both the cultivars. The efficient functioning of antioxidative enzymes, production of
PCs and GSH, helped in counteracting the effects of Cd namely in PBW-343, protected photosynthetic ability, and increased
the tolerance to Cd. 相似文献
9.
Ch. Ben Ahmed B. Ben Rouina S. Sensoy M. Boukhris F. Ben Abdallah 《Environmental and Experimental Botany》2009,67(2):345-352
Changes in photosynthetic performance, osmolyte accumulation and the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and polyphenol oxidase (PPO) were investigated in one-year-old olive cultivars (Chemlali, Meski and Picholine) subjected to contrasting water availability regimes under arid climatic conditions in Tunisia. Shoot elongation rates (SER) and photosynthetic performance were markedly reduced by the water deficit regime (WD) in all cultivars except for Chemlali, which proved to be superior to the other two cultivars with respect to drought tolerance. Higher photosynthetic performance (net photosynthesis (Pn), stomatal conductance (gs) and transpiration rates (E)) in the Chemlali and Meski cvs. compared to Picholine olive allowed them to maintain better plant water status and shoot elongation rates. Under WD conditions, Chemlali showed a greater capability for proline accumulation. Leaves grown under WD conditions showed signs of oxidative stress such as reduced chlorophyll and carotenoid concentrations. Nevertheless, different cultivars developed certain antioxidative defense mechanisms, including elevated SOD, APX and CAT activities. In contrast, PPO activity decreased under WD circumstances. Comparatively, Chemlali olive displayed better antioxidative enzyme activity, and thus better protection against oxidative stress. These results show that the ability of olive trees to up-regulate the enzymatic antioxidative system might be an important attribute linked to drought tolerance. These findings demonstrate that the association of higher Pn, proline accumulation and antioxidative defenses could be effective in a water-limited environment and may be useful selection criteria in breeding programs with the objective of improving drought tolerance and growth of olive trees, at least under the described environmental conditions. 相似文献
10.
The effect of hydrogen peroxide on the survival and activity of antioxidant and associated enzymes in Saccharomyces cerevisiae has been studied. A difference found in the response of wild-type yeast strains treated with hydrogen peroxide was probably
related to the different protective effects of antioxidant enzymes in these strains. Exposure of wild-type YPH250 cells to
0.25 mM H2O2 for 30 min increased activities of catalase and superoxide dismutase (SOD) by 3.4-and 2-fold, respectively. However, no activation
of catalase in the EG103 strain, as well as of SOD in the YPH98 and EG103 wild strains was detected, which was in parallel
to lower survival of these strains under oxidative stress. There is a strong positive correlation (R
2 = 0.95) between activities of catalase and SOD in YPH250 cells treated with different concentrations of hydrogen peroxide.
It is conceivable that catalase would protect SOD against inactivation caused by oxidative stress and vice versa. Finally, yeast cell treatment with hydrogen peroxide can lead to either a H2O2-induced increase in activities of antioxidant and associated enzymes or their decrease depending on the H2O2 concentration used or the yeast strain specificity.
Published in Russion in Biokhimiya, 2006, Vol. 71, No. 9, pp. 1243–1252. 相似文献
11.
The possible role of Zn and Cr as catalytic inducers of free radicals in wheat leaves was investigated. Treatment of excess
heavy metals decreased the chlorophyll and carotenoid content in wheat leaves with the increase in time of excision. A sharp
increase in proline accumulation was marked with the increase in metal concentration. Total peroxide content and lipid peroxidation
measured as malondialdehyde content showed uniform increase under metal treatment in excised leaves. At almost all concentrations,
catalase, guaiacol peroxidase and superoxide dismutase activities decreased with a minor increase in the earlier days of excision.
Though glutathione content decreased ascorbate content showed significant increase in wheat leaves under heavy metal treatment.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
12.
Effects of salicylic acid and salinity on apoplastic antioxidant enzymes in two wheat cultivars differing in salt tolerance 总被引:1,自引:0,他引:1
The effects of salicylic acid (SA) and salinity on the activity of apoplastic antioxidant enzymes were studied in the leaves
of two wheat (Triticum aestivam L.) cultivars: salt-tolerant (Gerek-79) and salt-sensitive (Bezostaya). The leaves of 10-d-old seedlings grown at nutrient
solution with 0 (control), 250 or 500 mM NaCl were sprayed with 0.01 or 0.1 mM SA. Then, the activities of catalase (CAT),
peroxidase (POX) and superoxide dismutase (SOD) were determined in the fresh leaves obtained from 15-d-old seedlings. The
NaCl applications increased CAT and SOD activities in both cultivars, compared to those of untreated control plants. In addition,
the NaCl increased POX activity in the salt-tolerant while decreased in the salt-sensitive cultivar. In control plants of
the both cultivars, 0.1 mM SA increased CAT activity, while 0.01 mM SA slightly decreased it. SA treatments also stimulated
SOD and POX activity in the salt-tolerant cultivar but significantly decreased POX activity and had no effect on SOD activity
in the saltsensitive cultivar. Under salinity, the SA treatments significantly inhibited CAT activity, whereas increased POX
activity. The increases in POX activity caused by SA were more pronounced in the salt-tolerant than in the salt-sensitive
cultivar. SOD activity was increased by 0.01 mM SA in the salt-tolerant while increased by 0.1 mM SA treatment in the salt-sensitive
cultivar. 相似文献
13.
Chilling Induced Oxidative Stress in Germinating Wheat Grains as Affected by Water Stress and Calcium 总被引:1,自引:0,他引:1
Wheat (Triticum aestivum L.) plants were subjected to mild water stress during grain filling at milk (early, medium, and late) and dough (early, soft, hard) stages. The grains harvested from stressed plants were subjected to low temperature stress of 10 °C for 24 h in presence or absence of 1 mM CaCl2, and embryos were examined for oxidative injury. The embryos of grains water stressed at milk and soft dough stages showed lowest contents of H2O2 and malondialdehyde and highest membrane stability index, ascorbic acid content, and activities of catalase, ascorbate peroxidase, and superoxide dismutase as compared to control embryos or water-stressed at other stages. Presence of Ca2+ in the medium reduced H2O2 and malondialdehyde content and increased ascorbic acid content, and catalase, ascorbate peroxidase and superoxide dismutase activities. 相似文献
14.
Physiological responses of two wheat (Triticum aestivum L.) genotypes (salt-tolerant DK961 and salt-sensitive JN17) to increased salt concentrations (50, 100, 150 mM NaCl: NaCl50, NaCl100, NaCl150) were studied. Photosynthetic capacity, irradiance response curves, contents of soluble sugars, proteins, and chlorophyll
(Chl), K+/Na+ ratio, and activities of antioxidant enzymes (superoxide dismutase, peroxidase, and catalase) in flag leaves were measured
on 7 d after anthesis. In control (NaCl0) plants, non-significant (p>0.05) differences were found in gas exchange and saturation irradiance (SI) between salt-tolerant (ST) and salt-sensitive
(SS) wheat genotypes. However, we found higher soluble sugar and protein contents, K+/Na+ ratio, and antioxidant enzyme activities, but lower Chl content and yield in ST wheat. Salinity stresses remarkably increased
soluble sugar and protein contents and the antioxidant activities, but decreased K+/Na+ ratio, Chl contents, SI, photosynthetic capacities, and yield, the extent being considerably larger in JN17 than DK961. Although
the soluble sugar and protein contents and the antioxidant activities of JN17 elevated more evidently under salt stresses,
those variables never reached the high levels of DK961. The antioxidant enzyme activities of SS wheat increased in NaCl50 and NaCl100, but decreased rapidly when the NaCl concentration reached 150 mM. Thus the ST wheat could maintain higher grain yield than
the SS one by remaining higher osmoregulation and antioxidative abilities, which led to higher photosynthetic capacity. Hence
the ST wheat could harmonize the relationship between CO2 assimilation (source) and the grain yield (sink) under the experimental conditions. 相似文献
15.
N.A. Khan 《Biologia Plantarum》2003,47(3):437-440
Effect of NaCl was studied on chlorophyll (Chl) synthesis and its intermediates (protoporphyrin IX, Mg-protoporphyrin IX,
and protochlorophyllide), dry mass, ethylene evolution, and activities of superoxide dismutase (SOD) and peroxidase (APX)
in wheat (Triticum aestivum L.) seedlings at 24, 48, and 72 h after germination. A conspicuous decrease in Chl synthesis, associated with increase in
ethylene evolution and SOD and APX activities, was noted as NaCl concentration was increased from 0 to 100 mM.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
H2O2 can freely crosses membranes and in the presence of Fe2+ (or Cu+) it is prone to participate in Fenton reaction. This study evaluated the concentration and time-dependent effects of H2O2-induced oxidative stress on MnSOD, Se:GPx and catalase and on aconitase. Acute and chronic H2O2 treatments were able to induce oxidative stress in HeLa cells as they significantly decreased aconitase activity and also caused a very significant decrease on antioxidant enzyme activities. The inhibition of enzyme activities was time- and concentration-dependent. Chronic treatment with 5 µM H2O2/h after 24 h was able to decrease all enzyme activities almost at the same level as the acute treatment. Acute and chronic treatments on antioxidant enzyme activities were prevented by cell treatment with ascorbic acid or N-acetylcysteine. These results indicate that antioxidant enzymes can also be affected by the same ROS they produce or neutralize if the time of exposure is long enough. 相似文献
17.
Effects of silicon on defense of wheat against oxidative stress under drought at different developmental stages 总被引:3,自引:0,他引:3
The effects of silicon application before sowing on the drought-induced oxidative stress and antioxidant defense in wheat
(Triticum aestivum L.) were investigated. Drought stress was applied by withholding watering till sampling at booting or filling stage. Application
of Si increased the water potential of drought-stressed plants at filling stage, whereas it did not at booting stage. The
superoxide dismutase (SOD) activity was inhibited and peroxidase (POD) activity was enhanced by drought at booting stage,
and no differences were observed due to the Si treatment. At filling stage, however, application of Si increased the SOD activity
and decreased the POD activity of drought-stressed plants. The catalase (CAT) activity was slightly increased by drought only
in the absence of Si and at booting stage. The activity of glutathione reductase (GR) was not greatly influenced. Application
of Si did not change the contents of H2O2, total soluble protein and protein carbonyl of drought-stressed plants at booting stage, whereas at filling stage, it decreased
the content of H2O2 and protein carbonyl and increased the content of total soluble protein. The content of thiobarbituric acid reactive substances
(TBARS) and the activities of acid phospholipase (AP) and lipoxygenase (LOX) in drought-stressed plants were also decreased
by application of Si at both stages. 相似文献
18.
Chris A. Pritsos Sami Ahmad Susan M. Bowen Andrew J. Elliott Gary J. Blomquist Ronald S. Pardini 《Archives of insect biochemistry and physiology》1988,8(2):101-112
The black swallowtail butterfly larvae, Papilio polyxenes, are specialist feeders that have adapted to feeding on plants containing high levels of prooxidant allelochemicals. Third, fourth, and fifth instar larvae were tested for their antioxidant enzyme activities, superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and glutathione peroxidase (GPOX), using 850-g supernatants from whole-body homogenates. The overall antioxidant enzyme profile for P. polyxenes was high compared to other insects, with activities ranging as follows: SOD, 1.1–7.5; CAT, 124–343; GR, 1.0–7.5; and GPOX, 0 units. To determine whether these antioxidant enzymes were inducible, P. poly xenes larvae were given a prooxidant challenge by dipping parsley leaves (their diet in the initial studies) in solutions of quercetin, such that the leaves became coated with this prooxidant flavonoid. Mid-fifth instar larvae fed on quercetin-coated leaves were assayed for antioxidant enzyme activities as was previously done with the larvae fed the standard diet. Food consumption and quercetin intake were monitored. SOD activity was increased almost twofold at the highest quercetin concentration tested. CAT and GR activity, on the other hand, were inhibited by increased quercetin consumption, with GR activity completely inhibited at the highest quercetin concentration after 12 h of feeding. GPOX activity, not present in control insects, was also not inducible by a quercetin challenge. These studies point out the key role that the antioxidant enzymes play in insect defenses against plant prooxidants. 相似文献
19.
Responses of antioxidative system to chilling stress in two rice cultivars differing in sensitivity 总被引:12,自引:0,他引:12
The responses of antioxidative system of rice to chilling were investigated in a tolerant cultivar, Xiangnuo-1, and a susceptible cultivar, IR-50. The electrolyte leakage and malondialdehyde content of Xiangnuo-1 were little affected by chilling treatment but those of IR-50 increased. Activities of suoperoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase, and ascorbic acid content of Xiangnuo-1 were remained high, while those of IR-50 decreased under chilling. The results indicated that higher activities of defense enzymes and higher content of antioxidant under stress were associated with tolerance to chilling. 相似文献
20.
Interactive effects of cadmium and aluminum on growth and antioxidative enzymes in soybean 总被引:3,自引:0,他引:3
The effects of Al, Cd and pH on growth, photosynthesis, malondialdehyde (MDA) content, and some antioxidant enzyme activities
of the two soybean cultivars with different Al tolerance were determined using a hydroponic culture. There were six treatments
as follows: pH 6.5; pH 4.0; pH 6.5 + 1.0 μM Cd; pH 4.0 + 1.0 μM Cd; pH 4.0 + 150 μM Al; pH 4.0 + 1.0 μM Cd + 150 μM Al. The
results showed that the low pH (4.0) and Al treatments caused marked reduction in the growth (root and shoot length and dry
mass), chlorophyll content (SPAD value) and net photosynthetic rate. Higher malondialdehyde content, superoxide dismutase
(SOD) and peroxidase (POD) activities were detected in the plants exposed to both Al and Cd than in those exposed to Al treatment
alone. An expressive enhancement of SOD and POD was observed in the plants exposed to 150 μM Al in the comparison with the
control plants, especially in Al-sensitive cv. Zhechun 2 which had also significantly higher Al and Cd content than Al tolerant
cv. Liao-1. Cd addition increased Al content in the plants exposed to Al + Cd stress, and cv. Zhechun 2 had relatively lower
Al content. The present research indicated that Al and Cd are synergistic in their effects on plant growth and some physiological
traits. 相似文献