Статьи журнала - Журнал стресс-физиологии и биохимии
Все статьи: 898
Статья научная
The seeds of two hybrids FSS64 and SF0049 of sunflower ( Helianthus annuus L.) were irradiated with different doses of gamma irradiation i.e., 10, 15, 20, 25 Krad from the source of cobalt Co60 at Nuclear institute for food and agriculture (NIFA), Peshawar. The irradiated seeds were sown in the research area of the department of Botany, Shaheed Benazir Bhutto University, Sheringal, Dir-Upper during the crop season of 2016. It was noted that a negative correlation was established in doses of 10, 15, 20, 25 Krad versus number of parameters like number of leaves, number of seeds per head and fresh seed weight. With the gradual increase in doses, decreases in mean values for the mentioned parameters were observed. Significant reductions in the mean values were observed for mentioned parameters in both the hybrids FSS64 and SF0049 of sunflower and consistently retardation was recorded with the increasing doses. Direct relationship occurred in the mean values of days taken to germination and maturity while on the other hand means values significantly raised with the rising of doses thus the duration of the mentioned parameters is increased...
Бесплатно
Статья научная
The present study was planned to investigate the possible role displayed by water stress and application of GB, SA or their interaction on some anatomical features in flag leaf at anthesis (after 95 days from sowing) by measuring leaf thickness, ground tissue thickness, number of hairs, metaxylem vessel area, xylem vessel area, phloem tissue area, vascular bundle tissues area, number of motor cells as well as number of opened and closed stomata on both upper and lower epidermis and some anatomical features of peduncle (peduncle diameter, tracheids area, metaxylem vessel area, xylem area, phloem area, vascular area, number of vascular bundle as well as opened and closed stomata) of the two wheat cultivars. Water stress markedly affected the anatomical features in flag leaves of both wheat cultivars. It caused massive decreases (P
Бесплатно
Effect of heat stress in tropical livestock and different strategies for its amelioration
Статья обзорная
Stress is a broad term, generally used in negative connotation and is described as the cumulative detrimental effect of a variety of factors on the health and performance of animals. Heat stress occurs in animals when there is an imbalance between heat production within the body and its dissipation. Heat stress is one of the wide varieties of factors which causes oxidative stress in-vivo. Reactive oxygen species (ROS), the major culprits for causing oxidative stress, are constantly generated in vivo as an integral part of metabolism. ROS may cause oxidative stress when their level exceeds the threshold value. They trigger progressive destruction of polyunsaturated fatty acids (PUFA), ultimately leading to membrane destruction. Body employs antioxidants to quench these free radicals. The enzymatic antioxidants like superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) act by scavenging both intracellular and extracellular superoxide radical and preventing lipid peroxidation of plasma membrane. Non-enzymatic antioxidants include vitamins like vitamins C, A and E, proteins like albumin, transferrin, glutathione (GSH) etc. Antioxidant nutrient supplementation especially vitamins C, A and E, zinc and chromium can be used to attenuate the negative effects of environmental stress.
Бесплатно
Статья научная
Myrosinase is an enzyme of cruciferous vegetables, hydrolyse glucosinolates. The breakdown products are involved in plant defence against insect and also have anti-fungal property. Myrosinase has been purified to apparent homogeneity from 5 days old germinated cauliflower seedlings having a specific activity of 12.71 units/mg proteins with 54.6 % recovery, using ammonium sulfate fractionation followed by gel filtration chromatography on Sephadex G-100. Effect of some metal ions and carbohydrates on the activity of partially purified cauliflower myrosinase was studied. Sr +2 at 4 mM concentration exhibited marked activating effect on the activity up to 2.7 fold while Fe +2 significantly inhibited. However, Sn +2 and Ba +2 increased the activity to a certain extent and then suppressed. On the other hand, some metal ions [Fe +2, Fe +3, Cu +2 and Zn +2] strongly inhibited the activity even at lower concentrations. Several carbohydrates viz., glucose, fructose, sucrose, maltose and sorbitol even at comparatively higher concentrations had little detectable inhibitory effects. Activation kinetics of myrosinase in presence of Sn +2 and Sr +2 were studied between 0- 20min. The rate of reaction was almost constant till 15 min and then slight deactivation was recorded at various concentrations used.
Бесплатно
Статья научная
Background: Plants have both and adaptive mechanisms for coping with the elevated metal concentrations and they are utilized to clean the polluted soil and water. Unlike angiosperms hyperaccumulators, fern hyperaccumulators are equipped with inherent biological characteristics that could be exploited in the phytoremediation strategies aimed at decontaminating polluted sites. spores can be successfully used to screen the hyperaccumualting ferns and also to test the toxicity of the metal contaminated samples. Purpose of the Study: In the present study, a preliminary attempt was made to compare the tolerance capacity of the spores of two ferns; Pteris confusa T. G. Walker and Pteris argyraea T. Moore against the heavy metal zinc (Zinc sulphate). Spores of the two ferns were cultured in Knop's liquid medium with various concentrations of zinc sulphate (0-200ppm). Results: In the case of P. confusa normal germination was observed in control, 120 ppm and 140 ppm and the germination of spores were failed in 160, 180 and 200 ppm of zinc supplemented cultures. In contrary, P. argyraea showed maximum percentage of spore germination in 140 ppm zinc supplemented cultures and the control and 120 ppm zinc sulphate supplemented cultures were failed to show the germination. The germination percentage and growth rate was decreased in high concentration of zinc sulphate. are showed more tolerance to heavy metal than protonema of P. argyraea. Conclusion: Difference in response of spores to the heavy metal zinc may be due the difference in the hyper-accumulating capacity of the ferns.
Бесплатно
Статья научная
Effect of honey on blood parameters in broiler chickens fed diet containing corticosterone (CORT) was examined. Arbor acres broiler chickens aged 28d were allotted to four groups. The birds received 30mg CORT/kg feed plus either 0 (C0H), 5 (C5H), 10 (C10H) or 15ml honey/l drinking water (C15H) for 7d. Blood sampling was carried out in five birds per treatment. Honey had significant (p 0.05) differences in MCV, MCH, MCHC, WBC, leukocyte differentials and H:L ratio, except for oesinophil (EOS; p 0.05) affected by treatment. Honey in drinking water of could be of help in improving the welfare of broiler chickens during stress episode by increasing the PCV, RBC and HB.
Бесплатно
Статья научная
Seed priming techniques have been used to increase germination, improve germination uniformity and seedling establishment under stressed conditions. Seed priming was used in Rye Mountain ( Secale montanum ) to increase seed germination and tolerance on stress exposure. Rye seeds were treated with various priming agents for different time and temperatures. The effect of priming was assessed on germination characteristics on subsequent exposure to drought (PEG -14 bar) stress for 7 days. Seed priming treatments significantly (p≤ 0.01) affected, Germination percentage (GP), normality seedling percentage (NSP), germination Index (GI), germination uniformity (GU), means time to germination (MTG), coefficient of velocity of germination (CVG), seedling vigour index (SVI) and coefficient of allometry(AC). Seed priming with gibberelic acid (GA) and salicylic acid (SA) (p≤ 0.01) increased germination characteristics as the compared to the unprimed. Seed priming with concentrations 25, 50 ppm of GA for 15 h at 10 ◦C and 25 ppm of SA for 12 h at 10 ◦C, may be considered as optimal treatment for priming of Secale montanum seeds in drought stress conditions. Also priming increased catalase (CAT) and ascorbate peroxidase (APX) as compared to the unprimed.
Бесплатно
Статья научная
The aim of this study is to determine the effect of hydrogen peroxide and thiourea on potato crop (quantum yield (Fv/ Fm), chlorophyll content, tuber diameter, tuber number and total tuber yield). The concentrations of these two chemicals are hydrogen peroxide: 0, 20, 40, 60 and 80 mM, and thiourea : 0, 250, 500, 750 and 1000 mM. The experiment was conducted in the farm of Chott- Mariem Institute during three months using variety 'Spunta' and arranged in a completely randomized block with three replications. Results show that there is no significant difference in tuber diameter between treatments and among the same treatment. However, tuber yield is significantly increased by 20 % by thiourea (250 mM). Maximum total yield was obtained at this concentration (810 g/plant). In addition, application of thiourea (500 and 750 mM) results in a significantly higher number of tubers number (5.7 and 5.2 respectively). In contrast, treatment with hydrogen peroxide brings about similar tuber yields. Although, application of hydrogen peroxide at low concentration (20 mM), decreases chlorophyll content and stresses plants, application of thiourea increases chlorophyll content, and improve quantum yield especially when it is applied at 250 mM.
Бесплатно
Статья научная
Extensively speaking, environmental stresses have a significant negative impact on agriculture. Plants have developed a multitude of defense responses that allow them to adapt, survive and reproduce under stress conditions. In the present study the effect of different individual stress treatments and their combined treatments on the yield, growth antioxidant activity and phytochemicals of ( Zingiber officinale cv-varada) were analyzed. A greenhouse experiment was conducted with 12 replications of each trial. The different stress treatments were attempted using Salicylic acid and Zinc Sulphate (10-2 & 10-3 Molar). Along with these two, drought is also taken as a third stress. The results of Individual and combination of stress treatments were obtained. The present study gives an idea about the effect of individual as well as combined stress treatments in both morphological (yield and growth parameters) antioxidant activity and the phytochemicals. A difference in the total phenolics, total flavonoids and antioxidant activity was observed in different trials. This also gives a clear picture about cross tolerance in which one stress influenced the effect of another.
Бесплатно
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.
Бесплатно
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.
Бесплатно
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.
Бесплатно
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.
Бесплатно
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.
Бесплатно
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.
Бесплатно
![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.
Бесплатно
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
Бесплатно
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.
Бесплатно
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).
Бесплатно
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.
Бесплатно
