Статьи журнала - Журнал стресс-физиологии и биохимии
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Статья научная
Late blight, caused by the pathogen Phytophthora infestans is an economical disease of potato worldwide. To better understand mechanisms of potato to resist this fungus, pathway signaling of TUB and PR5 were monitored using quantitative real-time PCR (qPCR) across four time points post infection. Results demonstrated that significant variance in the expression profiles of both genes in infected potato plants as compared to the non-infected controls. It is also notable that TUB and PR5 genes have a higher and faster expression in the resistant cultivar ‘Spunta’ as compared to the susceptible one ‘Draga’ with a maximum expression for TUB (1.8 and 1.4-fold) and PR5 (3.5 and 1.2-fold) respectively, at 48 hours post infection. Our data suggest that TUB and PR5 genes, positively regulate P. infestans -resistance in potato plants during disease progress, which can provide testable hypotheses that will need direct future experiments to define how these pathway signaling of both genes may be specified in potato defense system.
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Статья научная
The effect of Cr +6 with and without chelating agents were assessed in mung bean seedlings grown hydroponically. It was noted that the growth parameters showed a declining trend with increasing Cr +6 concentrations without chelate application. Among the seedlings grown with chelated chromium complexes, Cr +6–DTPA (10µM) showed highest growth rate of roots as well as shoots. At higher concentration of Chromium i.e. Cr +6 (100µM), there exhibited high chlorophyll content in mung bean leaves where the seedlings showed stunted growth. The seedlings treated without and with chelated chromium complexes showed increased proline content as compared to control. The enzymatic study showed that, the catalase activity was maximum in shoots as compared to roots and the reverse is true in the case of peroxidase activity i.e. the roots showed higher value than that of the shoots.
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Статья научная
A laboratory experiments was conducted for the assessment of physiological and biochemical responses of iron dust under the influence of different pH levels (6.5, 5.0, 3.0) and two concentration of iron dust (0.1 mg and 0.6 mg) with two particle size (100 µm and 300 µm) sprayed on the Cicer arietinum L. seed surface for fifteen day exposure. Observation was made on germination percentage and germination rate, vigour index, % phytotoxicity of root and shoot, chlorophyll, sugar, protein and proline content in both treated and control plant. The present results revealed that the seed color changes to brown under iron stress. The lower germination percentage and germination rate gradually decrease with pH of the medium but both the parameters were not significantly affected by the iron dust. Moreover higher % phytotoxicity was observed under all treatments compared to control and also lower values of this parameter were recorded in shoot than root. The reduction trend in chlorophyll and protein content was recorded at low pH but reverse result was recorded for sugar. Moreover highest proline was recorded under highly acidic condition.
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Effect of isotonic exercise (walking) on various physiological parameters in hypertension
Статья научная
Rationale: Walking is an isotonic aerobic exercise has been associated with reduced blood pressure and other physiological changes in observational o.p.d. studies. Study was conducted to determine the effect of isotonic aerobic exercise (walking) on blood pressure. Data resource: This study has been carried out in Kayachikitsa O.P.D., S.S. hospital, Faculty of Ayurveda, IMS, BHU. Study collection: The present work comprised a study of 84 hypertensive cases, which include 55 male, 29 females and 34 hypertensive controls, 50 hypertensive individuals. Among total cases participating in this study, control groups had not performed any exercise. All these cases of Hypertension were registered from Kayachikitsa O.P.D., IMS, BHU, for the duration of Jan 2009 to Jan 2011 and the selection was random irrespective of sex, occupation and socioeconomic deliberation. All the patients belonged to age group of 35 to 65 years. Two follow ups have been assessed during the research work i.e. initially, after one months and three months for all the physiological parameters. Conclusions: Aerobic isotonic exercise (walking) reduces blood pressure and other physiological changes i.e. Respiratory rate, Pulse rate, Blood sugar level and BMI in hypertensive exercise group (HTNE) and most of the control groups showed increase in physiological changes, this specify that lack of physical activity can cause various diseases. An increase in aerobic physical activity should be considered an important component of lifestyle modification for prevention and treatment of high blood pressure.
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Effect of metal ions, chelating agent and SH-reagents on radish (Raphanus sativus L.) root -amylase
Статья научная
Metal ions play vital roles in enzymes. They may also show sensitivity to various sulfhydryl reagents and chelating reagents. Effect of some metal ions, EDTA and sulfhydryl reagents on the activity of partially purified β-amylase of radish root were studied. Amylolytic activity of purified enzyme was increased substantially in the presence of Ca2+, Mg2+, and Zn2+. Some other divalent cations Cu2+, Pb2+, Sn2+, and Hg2+ almost completely ceased the enzyme activity. Cobalt (II), Manganese (II), and Iron (III) exhibited moderate activating effects on the activity. Of the monovalent cations, Na+ and Ag+ reduced the β-amylase activity, while K+ increased. The chelating agent EDTA was found to be effective in the enzyme. Sulfhydryl reagents, Iodoacetic acid and N-Ethylmaleimide showed marginal inhibitory effect, but p-hydroxymercuribenzoic acid (PCMB) almost completely stopped the enzyme activity. The addition of thiol compounds such as cysteine could reverse the inhibitory effect of heavy metals and PCMB. The results indicate that sulfhydryl groups of radish root β-amylase were essential for the activity although it is not clear whether the sulfhydryl groups were directly involved in catalysis.
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Статья научная
Seed priming was used in barley to increase seed germination and tolerance on stress exposure. Barley seeds were treated with PEG (Polyethylene 6000 mw). After 7 days our results showed that, seed priming treatments significantly (p≤ 0.01) affected germination percentage, normality seedling percentage, and germination index. Seed priming with PEG increased germination characteristics as the compared to the unprimed. Also, priming increased catalase as compared to the unprimed seeds. Therefore, the highest germination characteristics and catalase activity were attained from priming with PEG.
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![Effect of osmotic stress on seed germination and seedling characters of mung bean [Vigna radiata (L.) Wildzek]](/file/thumb/143180990/effect-of-osmotic-stress-on-seed-germination-and-seedling-characters-of-mung-bean.png "Effect of osmotic stress on seed germination and seedling characters of mung bean [Vigna radiata (L.) Wildzek]")
Статья научная
The Screening of osmotic stress was undertaken to investigate the effect of water stress and salinity stress on the seeds of mung bean ( Vigna radiata (L.) Wilczek) and its responses to drought tolerance at seedling stage. Water stress was simulated by non-ionic water-soluble polymer polyethylene glycol of molecular weight 6000 and salinity stress was induced with NaCl. The experiment demonstrated that osmotic stress caused by NaCl and PEG has a negative impact on the germination rate and seedling growth of Vigna radiata . Both NaCl and PEG inhibited germination and seedling growth in mung bean, but the effects of NaCl compared to PEG was less on germination and seedling growth.
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Effect of photoperiod on some biological parameters of Clarias gariepinus juvenile
Статья научная
Photoperiod effect on Growth parameters and cannibalism of Clarias gariepinus have been well documented in resent past, but little is known about the response of other biological parameters such as, Condition factor, Shooters composition, Body colouration and Blood glucose of this important tropical fish species to different photoperiods, therefore the present study was designed to evaluate these responses of the African catfish to 24 hours of light (00D:24L), 24 hours of darkness (24D: 00L) and 12 hour light / 12 hours darkness (12D: 12L). The six weeks experiment observed significant differences (P0.05) at the end of the experiment and were Significantly lower than value obtained at the start of the experiment, Shooters composition was highest in 00D:24L (41.5% i.e. 27 of 65) leading to high mortality (13.33%) due to cannibalism compared to 12D: 12L (Shooters =15.27% i.e. 11 of 72, Mortality= 4%) and 24D: 00L (Shooters=5.33% i.e. 4 of 75, Mortality= 0%) photoperiod. More so, 93.33% (70 of 75) of fish in the dark phase (24D: 00L) exhibited Deep shiny black body colouration, while 6.67% (5 of 75) was observed of Normal fish colouration. However the fishes in the 00D: 24L photoperiod were observed to be predominantly Lighter skin colouration, (80% i.e. 52 of 65= lighter colouration, 18.46% i.e. 12 of 65= Normal skin coloration and 1.53 i.e. 1 of 65= Deep black body colouration) while 12D: 12L were of Normal skin colouration (100% Normal skin colouration), also blood glucose was observed to increase as the light hours increased (P
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Статья научная
Background: Anxiety, depression and stress (ADS) are prevalent mental health disorders among university students due to the demanding nature of their academic pursuits. Pranayama yogic breathing (PYB), a controlled breathing technique has been suggested as a potential intervention to alleviate these psychological maladies.
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Статья научная
At Higher Institute of Agriculture of Chott Mariem, Sousse, Tunisia, this study was conducted to evaluate the interactive effect of salinity and seed priming on coriander. The experiment was carried out in completely randomized design with three replications consisting of four coriander genotypes (Tunisian cv, Algerian cv, Syrian cv and Egyptian cv) at two seed conditions (seed priming with 4 g/l NaCl for 12h or no seed priming). Results revealed that seed priming and salinity had significantly (p≤0.05) affected all the parameters under study. On the first hand, salinity stress had adversely affected growth, chlorophyll content, mineral composition (K + and Ca 2+) of coriander in all genotypes. Also, it activated Na + accumulation and synthesis of proline, soluble sugars and proteins. However, seed priming with NaCl had diminished the negative impact of salt stress in all cultivars and primed plants showed better response to salinity compared to unprimed plants. Maximum values were recorded in tolerant cultivar which is Tunisian one whereas minimum values were noted in sensitive cultivar (Algerian cv).
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Статья научная
Seed priming methods have been used to increase germination characteristics under stress conditions. The effects of drought stress (0, -4, -8, -12 and -16 bar) and salicylic acid 25 ppm at 15 °C for 15 h and ascorbic acid 25 ppm at 15 °C for 15 h on germination percentage, germination index, means time to germination, normal seedling percentage and enzyme activity were assessed in the laboratory for sorghum seeds ( Sorghum bicolor L. ). Results showed that the highest germination percentage (83.33%), normal seedling percentage (69.67%), germination index (25.29) and the minimum means time to germination (2.87) were attained from priming with salicylic acid in control conditions. Therefore, seed priming significantly (p≤ 0.01) increased germination characteristics as compared to the unprimed under drought stress. Also, priming increased catalase and ascorbate peroxidase as compared to the unprimed seeds.
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Effect of salicylic acid treatment on cadmium toxicity and leaf lipid composition in sunflower
Статья научная
The ameliorative effect of salicylic acid (SA) on cadmium (Cd) toxicity in sunflower plants was studied by investigating plant growth and fatty acid composition. Sunflower plants in two leaves stage were exposed to CdCl2 treatment (0, 50,100,150 and 200 µM) and then were treated with salicylic acid (0, 250 and 500 µM) as foliage spraying. One week after the last salicylic acid treatment,plants were harvested and growth parameters were measured. Oil of leaf was extracted in a Soxhlet system and fatty acid composition were measured by gas chromatography(GC). Statistical analyses showed excess Cd reduced growth parameters (fresh weight and length of stems and roots, fresh weight and number of leaves)and SA increased them compared with the control. Maximum reduction in these parameters was at 200 µmol Cd and 0µmol of SA. Cd caused a shift in fatty acids composition, resulting in a lower degree of their unsaturation and an increase in saturated fatty acids in sunflower leaves,whereas SA improved them. SA, particularly increased the percentage of linolenic acid and lowered that of palmitic acid by the same proportion. These results suggest membrane integrity due to lipids est that SA could be used as a potential growth regulator and a stabilizer of protection of cadmium-induced oxidative stress to improve plant resistance to Cd stress.
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Статья научная
Salinity is a serious environmental constraint to crop production in many parts of the world and the development of crops with improved salt tolerance is proposed as part of solution to this problem. This research was performed out in order to study the effects of different salinity levels on germination, growth, dry weight, proline, water soluble carbohydrate and chlorophyll content of three barley (Hordeum vulgare L.) cultivars named Jonoob (INC-54), Reyhan (INC-45) & Nosrat (INC -47).The experiment was carried out using factorial based on completely randomized design with three replications. Seven old seedlings after germination were transferred to Hoagland nutrient solution under the effect of salinity levels (0, 50, 150 and 250 mM NaCl)in during seven days. Data variance analysis showed that seed germination of three barley cultivars was significantly (PReyhan>Nosrat. The results showed that, increasing in salinity decreased all growth parameters. Salinity stress decreased shoot and root length, root dry weight and chlorophyll contents in every three cultivars. But decreasing of chlorophyll was less in Nosrat compared to two other items. Proline content and soluble carbohydrate were increased in all of the three cultivars with enhance of NaCl concentration. By increasing of salinity stress accumulation of proline and soluble sugar content in leaves of Nosrat cultivar was more than other cultivars. As saltiness increases resistance natural responses in this plant gets better considering less decrease in chlorophyll amount and strategy of more production about praline and sugar solution compared to two other items.
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Effect of salt stress (NaCl) on biomass and K+/Na+ ratio in cotton
Статья научная
A pot experiment was conducted to evaluate performance of Upland cotton (Gossypium hirsutum L.)varieties, (A118), Aleppo33/1 (A33/1), Aleppo90 (A90), Raqqa5 (Raq5) and Deir-Ezzor22 (DE22), grown under different salinity concentration 0, 50, 100 and 200 mM NaCl for 56 days. Results indicated that increasing salinity decreased fresh and dry leaf and root weights. Also, leaf K+/Na+ ratio was decreased as increasing salinity levels in all tested varieties. This reduction for the all indicators tested was relatively more pronounced in A118 than DE22. Thereby, DE22 variety relatively performed better under salinity compared to the other tested varieties. Based on this investigation, it can be concluded that DE22 and Raq5 are relatively characterized as salt tolerant, while A90 as moderate salt tolerant. On the other hand, A118 and A33/1 could be considered as salt sensitive.
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Статья научная
Salinity is one of the major environmental problem that lead to a deterioration of agricultural land and, as a result, to a reduction in crop productivity worldwide. This research tested the effect of different salinity levels on germination and early seedling growth of three pepper ( Capsicum annuum L.) cultivars which were "Beldi", "Baklouti" and "Anaheim Chili". Experimental treatment included 7 concentrations of NaCl (0, 2, 4, 6, 8, 10 and 12 g/l). Results indicated that all investigate traits were affected by salt stress. Salt stress affected on germination parameters and radicle and plumule length. Fresh weight and dry weight of evaluated seedlings was also affected. "Anaheim Chili" cultivar was shown to be the most restraint cultivar to salt stress in comparison to "Beldi" and "Baklouti" cultivars.
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Effect of salt stress on expression of carotenoid pathway genes in tomato
Статья научная
Carotenoids, the naturally occurring isoprenoids form essential components of photosynthetic antenna and reaction centre complexes. Thus they play a significant role in absorption, dissipation and transfer of light energy for the process of photosynthesis. The effects of salt stress on carotenoid gene expression in tomato leaves were studied. For that tomato plants were subjected to different concentration of salt water. Morphological characters such as plant height, no. of fruits per plant, chlorophyll content and expression of four major carotenoid pathway genes such as phytoene synthase, phytoene desaturase, zeta carotene desaturase and lycopene beta cyclase were analysed. The quantitative expression analysis using real time PCR has shown a decrease in the expression of all the studied genes as the salt concentration increased. Among the different concentrations of NaCl used for the experiment, it was seen that 200 mM was most detrimental for the carotenoid gene expression. Lycopene beta cyclase, the enzyme that converts lycopene to beta carotene was seen to be highly affected compared to other genes studied showing a 1.87 fold inhibition in its expression at 200 mM NaCl.
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Effect of salt stress on grain reserve composition in ten durum wheat cultivars
Статья научная
Saline soils are defined as those that contain sufficient soluble salts in the root zone to impair plant growth. Wheat is one of the three major cereals dominating world agriculture to date. Durum wheat is the hardest wheat and the concept of durum wheat quality is complex and confusing. Quality factors such as protein content, gluten strength and color have different priorities in various durum wheat markets. Changes in the grain quality of ten durum wheat cultivars under salt stress studied at the greenhouse condition. A factorial experiment was carried out based on completely randomized design with three replications. Treatments were salinity including 0, 60 and 120 mM and ten durum wheat cultivars (Boomer, PGS, 71135, 61130,605, C1351, KND, KDM, Haurani and G1252). Biochemical grain reserves such total protein and carbohydrate content, gluten, phosphorous and beta carotene were measured. Results showed that interaction of salt and cultivars was significant for all studied traits except of beta-carotene. At this experiment, gluten content changed very little with salinity levels. Cultivar 71135 at all salinity levels had the highest gluten content. With increasing of salt severity, the content of protein and carbohydrate decreased and content of phosphorous increased compared with control. In 60 mM salinity, cultivars 61130 and 71135, in 120 mM, 71135 and KDM and in control, 61130 and PGS respectively, had the highest and lowest content of protein. Cultivars 71135 and 61130 had the highest and PGS had the lowest phosphorous content in control. At 60 mM, cultivars 71135 and PGS respectively, had the highest and lowest phosphorous content. At 120mM, 71135 and Haurani respectively, had the highest and lowest phosphorous content. In three salt levels, cultivar 71135 was determined as the most tolerant cultivar according to content of grain reserve composition results.
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Effect of short term NaCl stress on cultivars of S. lycopersicum: a comparative biochemical approach
Статья научная
Tomato is a crop plant with high fruit nutritive value and other useful properties. The cultivation of this species is dependent on many environmental factors, e.g. temperature, salinity, nutrients etc, affecting the yield and reproductive potential of the plant. Salinity in soil or water is of increasing importance to agriculture because it causes stress to crop plants. Plants exposed to an excess amount of salts such as NaCl undergo osmotic stress, water deficit and ionic imbalances and can increase production of reactive oxygen species(ROS). Higher plants possess very efficient enzymatic and non-enzymatic antioxidative defense mechanisms that allow the scavenging of ROS and protection of cellular components from oxidative damage. Studies were conducted to investigate the effect of short term salinity stress on some physiological alterations in three tomato cultivars Pusa Ruby(PR), Punjab Keshari (PK) and Ailsa Craig(AC). Some biochemical parameters (anthocyanin and carotenoeid content, polyamines, proline, cysteine, peroxidase and malondialdehyde) were set and applied at two month old stage of tomato plants. Three tomato cultivars were grown in 0.5xMS for 2 months and at this stage, they were treated with 0 and 200mM NaCl for a short period of six hours in hydroponic conditions. The genotypes exhibited different responses in terms of different osmoprotectant, antioxidant, and pigment level. The relationships among the salinity and accumulation of these compounds in leaf were then determined. It was concluded that, tomato cultivars under study responded differently showing their sensitivity or tolerance to salinity stress. Among three cultivars PK appeared to be more tolerant genotype than the other two cultivars PR and AC. PK could rapidly evolve physiological and antioxidant mechanisms to adapt to salt and manage the oxidative stress. The research was conducted in a completely randomized design with three replications.
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Статья научная
Phytotoxic effects of Pb as Pb(NO 3) 2 and silver nanoparticles on Mung bean ( Vigna radiata ) planted on contaminated soil was assessed in terms of growth, yield, chlorophyll pigments, phenol and flavonoid content at 120 ppm concentration. Experiments were carried out with 4 treatments in 10 days. Treatments were including (T1) control, (T2) silver nanoparticles (50 ppm), (T3) Pb as Pb (NO 3) 2 (120 ppm) and (T4) silver nanoparticles (50 ppm) plus Pb as Pb(NO 3) 2 (120 ppm). Regarding the pigment content, silver nanoparticles-treated plants showed a remarkable increase of chlorophyll. The loss of chlorophyll content was associated with disturbance in photosynthetic capacity which ultimately results in the reduction of Vigna radiate growth. Pb caused a fall in the total content of phenols, while the content of flavonoid not significantly changed. The minimum decrease in root length, weight of root fresh and stem fresh was observed in T4 group, but this factors increased in the other treatments. Also, length of stem and seedling height decreased in control group. Increase length and fresh weight of stem in Pb-treated plants suggest that compatible solutes may contribute to osmotic adjustment at the cellular level and enzyme protection stabilizing the structure of macromolecules and organelles.
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