Журнал стресс-физиологии и биохимии / Journal of Stress Physiology & Biochemistry
2014. — Выпуск 1
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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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The aim of the present study was to examine the energy strategy in response to the cold temperature and food shortage. The survival rate, body mass, body fat content, serum leptin levels, basal metabolic rate (BMR) and nonshivering thermogenesis (NST) as well as masses and the morphology of visceral organs and the digestive tract were measured in Eothenomys miletus that was subjected to the cold temperature (5°C) and food restriction (80% of ad libitum food intake). The results showed that body mass, body fat content, serum leptin levels, brown adipose tissue (BAT) mass and dry mass of digestive tract in cold and food restriction group were lower than those in control group. In contrasts, BMR and NST in cold and food restriction group was significantly higher relative to control group. The rate of survival was 18.18% in E. miletus during cold and food restriction after 4 weeks acclimation. In addition, serum leptin levels were positively correlated with body mass and body fat content, and negatively correlated with BMR and NST. These results suggested that E. miletus apply physiological adjustments to adapt cold and food lacking external environment by reducing body mass, body fat content, and increasing energy metabolism. However, energy intake is insufficient to compensate for the increase in energy requirement due to cold, led to body mass decreased and mortality rate increased. Moreover, serum leptin may acts as a fat signals, and may be involved in the regulation of energy balance and body mass in E. miletus under the cold temperature and food restriction.
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A greenhouse test was conducted in 2011 and 2012 growing seasons at Giza Agricultural Research Station to evaluate the reaction of six cotton genotypes to damping-off incited by Fusarium oxysporum . Damping-off incidence on the genotypes ranged from 70-88%. In general, the genotypes could be divided into highly susceptible, susceptible, and moderately susceptible. Data for damping-off incidence and level or activity of some biochemical components (phenols, peroxidase, and polyphenoloxidase) were entered into a computerized linear regression analysis. The analysis contrasted seven predictive models by using the biochemical components, singly or in combination, as biochemical predictors. It was evident that models nos. 2 and 6 were the best models for predicting incidence of damping-off. The superiority of these models was attributed to their high R² values (0.748 and 0.902, respectively) and the significance of their F. values (P = 0.026 and P = 0.031, respectively). The results of the present study suggest that peroxidase alone or both peroxidase and polyphenoloxidase, which may or may not parts of damping-off resistance mechanisms, can be used as biochemical markers to predict resistance to damping-off incited by F. oxysporum .
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Olive oil is beneficial effects are not only related to its high content of oleic acid, but also to the antioxidant potential of its polyphenols. In this study, we assess the effects of virgin olive oil on mercuric chloride induced oxidative damage in the liver of rats. Adult male Albinos Wistar rats randomly divided into four groups, were the first was served as a control, whereas the remaining groups respectively treated with: virgin olive oil (2ml/ kg b.w; by gavage), mercuric chloride (0.5 mg/kg body weight i.p) and combination of virgin olive oil and HgCl 2. Change in liver enzyme activities, thiobarbituric acid reactive substances (TBARS) level, antioxidants and reduced glutathione (GSH) contents were determined after 2 weeks of experimental period. Exposure of rats to mercuric chloride caused a significant increase the lipid peroxidation level along with corresponding decrease in the reduced glutathione and various antioxidant enzymes in liver. And increase in serum: glucose level, APL and transaminases activities and decreased in total protein and albumin levels. Furthermore, treatment with mercuric chloride caused a marked elevation of liver weight and decreased body weight. Supplementation of virgin olive oil resulted in decreased of lipid peroxidation level and in the serum: AST, ALT and APL activities were decreased along with increase in total protein, albumin and liver GSH levels. The activities of antioxidants enzymes: glutathione peroxidase (GSH-Px) and glutathione –S-transferase (GST) were also concomitantly restored to near normal level by virgin olive oil supplementation to mercuric chloride intoxicated rats. Liver histological studies have confirmed the changes observed in biochemical parameters and proved the beneficial role of virgin olive oil. The results clearly demonstrate that virgin olive oil treatment augments the antioxidants defense mechanism in mercuric chloride induced toxicity and provides evidence that it may have a therapeutic role in free radical mediated diseases.
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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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This study evaluates the anaesthetic properties of freeze-dried leaf extract of Tephrosia vogelii on the African catfish Heterobranchus longifilis juveniles. Experimental fish of Mean weight 115.00 were obtained from River Benue at Makurdi, Nigeria and acclimatized at the hatchery of University of Agriculture Makurdi for two weeks. Four H. longifilis were selected randomly for both control and treatment groups. Each treatment fish was weighed and injected intramuscularly 0.05ml of the extract at concentrations of 0.01, 0.02, 0.03, 0.04, 0.05 and 0.06g/l using a 2ml heparinized syringe. The result showed that H. longifilis in treatment group passed sequentially through the first three stages of anaesthesia but could not attain total loss of equilibrium (stage 4 of anaesthesia). The result showed that treatment group of fishes passed sequentially through the first three stages of anaesthesia but could not attain total loss of equilibrium (stage 4 of anaesthsia). Behavioural responses included mucus secretion, slow and erratic swimming, excrement discharge, increase in opercular beat rate, strong retention of reflex action, partial loss of equilibrium and colour change. The induction time showed a declining pattern with increasing concentration of the extract in the treatment levels with significant differences (P<0.05) observed at all three stages of anaesthesia. Recovery time showed the reverse order with significant differences (P<0.05) at all levels of concentrations. The opercular beat rate before and after injection, did not follow a definite pattern (P>0.05). The most effective concentration was 0.06g/l with an induction time of 32.00±1.76 seconds and a recovery time of 182.00±3.46 minutes. The result of this study revealed that the freeze-dried bark extract of T. vogelii can be used as a tranquilizer for transporting fish over average distances, biopsy and morphological evaluation.
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Salinity is one of the environmental challenges in the world affecting on several physiological processes and the most limiting factor of plant productivity and quality. Two pot experiments were conducted at the wire house of National Research Centre, Cairo, Egypt during two successive seasons of 2010/2011 and 2011/2012 to assess the efficiency of two antioxidant vitamins (ascorbic acid at 1.13 and 2.27 mM or α tocopherol at 0.46 and 0.93 mM) and/or salinity stress at (0.0, 3.08, 6.16, 9.23 ds/m) on photosynthetic pigments, protein, carbohydrate, minerals, oil contents and yield as well as fatty acids composition of the yielded oils of three flax cultivars (Sakha 3, Giza 8 and Ariane). The data revealed that salinity stress caused significant and gradual decreases in total photosynthetic pigments, polysaccharides, total carbohydrates, total proteins and the uptake of Mg, K, Ca and P in the leaves of three flax cultivars with increasing salinity levels (3.08, 6.16, 9.23 ds/m). Otherwise, significant and gradual increase appeared in both Na and Cl. Ascorbic acid and α tocopherol at different concentrations caused significant increases in photosynthetic pigments, total carbohydrates and protein contents in the leaves of flax plants irrigated either with tap water or saline solution as compared with their corresponding controls. Exogenous application of ascorbic and α tocopherol at different concentrations exhibited decreases in Na and Cl whereas increases appeared in Mg, K, Ca and P relative to their corresponding control. Ascorbic acid (1.13 and 2.27 mM) and α tocopherol (0.46 and 0.93 mM) caused marked increases in yield and yield attributes of three flax cultivars either in plants irrigated with tap water or saline solution as compared to corresponding control. Ascorbic acid effects were more pronounced than α tocopherol effects. In addition, the higher level of two vitamins was more pronounced than the lower level. Regarding plants irrigated with tap water, it was noted that ascorbic acid at 2.27 mM caused significant increase in oil content by 19.75 % in Giza 8 whereas α tocopherpl at 0.93 mM caused significant increase by 14.83% in Sakha 3 and 13.70% in Ariane. Regarding plants irrigated with saline solution (9.23 ds/m), it was found that α tocopherol at 0.93 mM caused significant increase in oil % by 30.84 %, 9.66 % and 35.62 % in Sakha 3, Giza 8 and Ariane cv. respectively. Responses of three flax cultivars to salt stress were more or less similar; since salinity stress caused marked increases in total saturated fatty acids accompanied by decreases in total unsaturated fatty acids as salinity levels increased. Myristic acid (C14:0) and oleic acid (C18:1) were the most affected saturated and unsaturated fatty acids in response to different salinity levels. The effect of ascorbic acid at 2.27 mM and tocopherol at 0.93 mM were found to be contrary to that of salinity as marked increases appeared in unsaturated fatty acids as compared with control plants. It could be concluded that foliar application of ascorbic acid and α tocopherol could play an enhancement role and alleviate the harmful effect of salinity stress on many metabolic and physiological processes of three flax cultivars that reflected in increasing seed yield quality and quantity.
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Plants are always under threat due to various biotic and abiotic stresses. They respond to such threats by an efficient antioxidative enzyme system such as catalase. The presence of petroleum in soil is a stressful environmental factor for plants. In this study, cellular and biochemical changes were investigated in the shoot of lentil grown in the crude oil-polluted soil. Transmission electron microscope micrographs showed various injuries in the level of subcellular content including nucleus, chloroplast and mitochondria. In the treated samples, catalase activity and its kinetics factors (Vmax and Km) were different from the control. In the treated, Km of the enzyme was lower than that of the control. Temperature and pH profiles of the enzyme were different in the control and treated samples. Catalase purification in both treated and control samples showed that two catalase isoforms were expressed in the treated sample in comparison to the control, in which only one type of catalase was detected.
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Phytremediation has emerged as a practical approach to clean up metal-polluted soils. In this study the role of sunflower ( Helianthus annuus L.) plants as a potential phytoremediator to soils contaminated with cadmium (Cd) and lead (Pb) was investigated. Our results showed that the effect of Cd was stronger on the growth of the roots, while the effect of Pb was stronger on the shoots of sunflower seedlings. At the physiological level, Cd treatment was found to induce low levels of lipid peroxidation and membrane leakage with less affected photosynthesis in the leaves of the treated sunflower seedlings compared to the effects of Pb. The results presented here showed that a high amount of the total absorbed Cd (88.84%) was accumulated in roots, while a high amount of the total absorbed Pb (71.39) was tranlocated to shoots of sunflower seedlings. Similar trends of Cd and Pb allocation between roots and shoots at the yield stage were recorded. We suggest here that sunflower plants may remediate Cd contaminated soils through phytostabilization, while may remediate Pb contaminated soils through phytoextraction. Finaly, the trace amounts of Cd and Pb that were accumulated in seeds recommends sunflower plants to be used safely and economically for cleaning up soils contaminated with Cd and/or Pb.
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A study has been conducted to observe the toxic effect of leachate from cigarette origin tobacco leaf and extracts of cigarette smoke on Bengal gram ( Cicer arietinum L.). Results showed that germination index significantly vary with concentration. Almost all the treated seeds germinated within five days of incubation. However tobacco leaf extract showed 85 % germination with same days of incubation. The growth parameters like root length, shoot length, number of leaf per plant, shoot diameter, root and shoot fresh and dry weight etc. changes according the concentration gradient. The highest pigment content and germination index were recorded in treatment T4.
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A pot experiment was conducted to evaluate the beneficial effect of grain presoaking in spermine (0.15 mM), spermidine (0.3 mM) and their interaction on waste water tolerance of wheat plants ( Triticum aestivum L.) variety Sakha 94. In general, waste water caused significant increases in the leaf thickness and ground tissue thickness in flag leaves as well as metaxylem vessel area, xylem vessel area, vascular bundle area in flag leaf and peduncle of main shoot of wheat plants. On the other hand leaf thickness and ground tissue thickness appeared to decrease at concentration 100% of waste water. Irrigation of wheat plants with waste water at all examined concentrations decreased phloem area in flag leaves and peduncle of main shoot of wheat plants. The application of spermine, spermidine or their interaction induced some modifications in the anatomical features of the flag leaf and peduncle of main shoot which appeared to be an adaptive response to heavy metals in applied waste water. Furthermore, Irrigation of wheat plants with waste water stress decreased significantly grain yield / plant. The applied polyamines appeared to alleviate the effect of heavy metals stress in waste water on grain yield. The effect was more pronounced with spermine +spermidine treatment. For anatomical features, the economic yield of wheat plants appeared to be positively correlated with the phloem area but negatively correlated with vascular bundle area and xylem area in flag leaf and peduncle of main shoot.
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The present study aimed to evaluate the allelopathic potential of root extract of Rumex dentatus L. and various allelochemicals on some physiological parameters in roots of Cicer arietinum L. The tested allelochemicals were benzoic, caffeic, cinnamic, ferulic, gallic, sinapic and vanillic acids. Seed germination of Cicer was inhibited by Rumex extract. Lipid peroxidation and hydrogen peroxide production increased gradually in response to extract concentration as well as allelochemicals treatment. The total soluble protein decreased whereas the total phenol increased under the various treatments. The activities of superoxide dismutase (SOD: 1.15.1.1) and catalase (CAT: 1.11.1.6) increased continuously with increasing extract concentration. However, peroxidase (POD: 1.11.1.7) increased sharply at 2% (w/v) followed by reduction at the higher concentrations and reached 1.1 U g-1 fresh weight at 10% (w/v) which was still higher than that of the control value. Ferulic acid was the most effective inducer for SOD activity followed by cinnamic acid. The POD activity increased remarkably particularly with cinnamic, benzoic and gallic acids. Sinapic, ferulic and coumaric acids enhanced CAT activity by 150.4%, 139.5% and 124.4%, respectively. The results reveal the possible use of R. dentatus as bioherbicide.
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High temperature is a serious threat to crop production. Brassinosteroids (BRs), a group of plant steroidal hormones, can reduce effects of abiotic stresses. The present study was aimed to study the potency of brassinosteroids on high temperature induced changes in Indian mustard ( Brassica juncea L.) for effects on growth, chlorophyll, photosynthesis, photosystem II, antioxidant system and proline. Surface sterilized seeds of Indian mustard were sown in pots, grown for 21 days and treated with double distilled water or 0.01 µM of 28-homobrassinolide. Treated plants, after 24 h, were exposed to 30°C or 40°C for 48 h. One set of plants were kept at ambient temperature, 25°C, as the control. Plants were harvested at 30 days stage of growth to assess the various parameters. Plants exposed to 40°C had a decline in growth, leaf water potential, chlorophyll, photosynthetic rate, and activities of carbonic anhydrase (E.C.4.2.1.1) and nitrate reductase (E.C.1.6.1.1). The 28-homobrassinolide alone improved growth and photosynthesis responses along with various enzymes activities. Treatment of plants with HBL prior to exposure to 40°C, partially reduced damage and completely controlled damage when exposure was to 30°C. Levels of the antioxidative enzymes catalase (E.C.1.11.1.6), peroxidase (E.C.1.11.1.7), and superoxide dismutase (E.C.1.15.1.1), and the level of proline increased in response to 30 or 40°C and were further enhanced in the presence of 28-homobrassinolide. Plants grown under high temperature had increased levels of H 2O 2; application of HBL before temperature treatment decreased H 2O 2 content compared to the control. Elevated levels of antioxidative enzymes and proline might be responsible for conferring tolerance to high temperature stress in Indian mustard and overcome the loss of productivity of the crop.
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Алюминиевая токсичность является основной причиной недобора урожая зерновых культур на кислых почвах. Известно, что механизмы токсического действия алюминия различны по своей биохимической природе, а изучение фитотоксических эффектов металла усложняется из-за многообразия его химических форм и способности к миграции в почве и воде. В работе изучен качественный состав корневых экссудатов гречихи обыкновенной. Выявлены органические комплексообразователи – щавелевая кислота и фенольные соединения. Показана роль этих комплексообразователей в устойчивости гречихи к алюмокислому стрессу, участие в процессах внешней и внутренней детоксикации. При обработке исследуемых растений алюминием наблюдалось увеличение в 2,5 раза количества выделенной в околокорневой почвенный раствор щавелевой кислоты, содержание в корневых выделениях фенольных соединений, наоборот, снизилось в 3 раза. При этом отмечено повышение активности основного фермента синтеза фенольных соединений – фенилаланин аммиак-лиазы в 2 раза.
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The production of fresh and dry matter of maize, wheat, cotton, broad and parsley plants show a variable response to the elevation of salinity stress. The production of fresh and dry matter of shoots and roots in wheat and broad bean plants tended to decrease with increasing NaCl concentration, salt stress progressively decrease in fresh and dry matter yield of maize plants. The increase in salinization levels induced a general insignificant change in production of fresh and dry matter of both organs of parsley plants. However, salinity induced a marked increase in the values of fresh and dry matter yields of cotton plants grown at the lowest level (-0.3 MPa NaCl) and a reduction at higher salinization levels. Leaf area of unsprayed plants was excesivly decreased with the rise of osmotic stress levels especially at higher salinity levels of maize, wheat, cotton, and broad bean and parsley plants. the total pigments concentration decreased with rise of salinization levels in maize and cotton, these contents remained more or less un affected up to the level of 0.6 MPa NaCl in wheat and up to 0.9 MPa in parsley plants, there above, they were significantly reduced with increasing salinity levels. In broad bean plants the total pigments contents showed a non-significant alterations at all salinity stress. Spraying the vegetative parts of the five tested plants with 200 ppm of either GA3 or kinetin completely ameliorated the deleterious effect of salinity in fresh, dry matter, leaf area and pigment contents.
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The objective of this research was to evaluate the effect of seed priming with osmo and hormone priming on growth and seed reserve utilization of millet seeds under drought stress. Treatments were combinations of 4 levels of drought stress (0, -4, -8 and -12 bar) and 3 levels of seed priming and control with 3 replications. Results showed that with increase in drought stress, germination components such as germination percentage, germination index, mean time to germination, normal seedling percentage, seedling length, seedling dry weight, weight of utilized (mobilized) seed and seed reserve utilization efficiency decreased, but seed priming showed lower reduction. The highest germination characteristics and seed reserve utilization was obtained by priming in control conditions. It is concluded that priming results in improvement in germination components of millet in drought stress conditions.
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One year old seedlings of Simarouba glauca were subjected to water stress for 4, 8, 12 and 16 days. The foliar sprays of 50 ppm salicylic acid (SA) and 10 ppm Putriscine, Gamma amino butyric acid (GABA) and Abscisic acid (ABA) were applied before and after water stress. It was observed that polyphenols, tannins, alkaloid and flavonoid contents were increased with increasing water stress treatments. Foliar applications of growth regulators ameliorate water stress and exhibits induction of secondary metabolites like coumarins, sterols, xanthoproteins, cardiac glycosides and saponins. It was also noticed that foliar application of SA, GABA, ABA considerably increases all these secondary metabolites which will help to improve the medicinal potential of Simarouba glauca under water stressed condition.
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This study investigated the effect of shikimic and salicylic acids at the concentrations of 0.4 and 0.7 mM, respectively, or their combination as phenolic compounds and Ridomil MZ at the concentration of 250 g/100 L as a fungicide on osmotic pressure (OP), solutes allocation, organic acids, inorganic ions and relative water content were quantified in Vicia faba leaves infected by Botrytis fabae . Pathogen induced noticeable decrease in osmotic pressure, total soluble sugar (TSS) and inorganic osmolytes (i.e. Na +, K +, Ca 2+, Mg 2+ and Cl -) while caused obvious increase in proline, total soluble nitrogen (TSN) and organic acids (i.e. Keto and citric acids) in water extract of the leaf of faba bean plants. Furthermore, pathogen caused marked decrease in relative water content (RWC) of infected leaves and as a consequence the saturation water deficit (SWD) was increased. Exogenous application of shikimic acid, salicylic acid or their combination could counteract the adverse effects of B. fabae on osmotic adjustment by inducing additional increase in proline, total soluble sugars, total soluble nitrogen and organic acids which in turn increase the osmotic pressure as well as relative water content in leaves of infected plants. Recovery of osmotic adjustment as well as leaf turgidity of infected host by using these chemical inducers may encourage the using of them as protective control means. The results of the present study showed also that the application of chemical inducers such as shikimic and salicylic acids or their interaction increased the resistance of Vicia faba against the chocolate spot disease.
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Background – Environmental deterioration due to heavy metal pollution is a major global concern for its immense importance in the ecosystem. Indiscriminate use of heavy metals for rapid urbanization and industrial exploration is a pressing threat to human health. Among this Cd and Cr contamination is most dangerous as these metals directly enter into the food chain due to their higher solubility and mobility. Identification of a metal tolerant native plant species would be helpful to decontaminate Cd and Cr polluted land. In our previous study, field investigations were conducted to evaluate the tolerance potential of Alligator weed to Cd and Cr.Alligator weed [ Alternanthera philoxeroides (Mart). Griseb ],is the most widely distributed perennial stoloniferous herb in these contaminated areas in and around Kolkata. Purpose of the study – To establish metal tolerant capacity of the species , different biochemical parameters assessing its metal accumulation capacity and reflecting its detoxification mechanism were studied. For these purpose, the same plant collected from the highest metal contaminated area was grown under laboratory condition with external application of various concentration of Cd and Cr individually and synergistically (0.5, 0.8, 1.0, 1.2, 1.5, 1.8 mM). To estimate the hazardous effects of Cd and Cr on this weed, membrane damage was quantified in form of lipid peroxidation i.e MDA production. The metal uptake and accumulation potential was estimated by measuring the Cd and Cr concentration in root and shoot. Some soil parameters such as Orgnaic Carbon, Cation exchange capacity were also studied to explain the bio availability of metals. Various biochemical parameters such as free proline content, non protein- thiol content and zymogram analysis of antioxidative isozymes (such as, Guiacol peroxidase, superoxide dismutase, glutathione reductase and ascorbate peroxidase) were studied to assess its metal resistant capacity. Result: The acidic pH and enhanced Cation Exchange Capacity of soil made both Cd and Cr more bioavailable with increasing metal concentration. Linear increase in metal uptake and accumulation was recorded upto an optimum level at 1.0 mM, 1.2 mM for Cd and Cr respectively, evident from Translocation Factor > 1. Gradual increase in membrane damage reflected the devastating effect of both Cd and Cr. But enhanced free proline content and non protein thiol content provide enough detoxification capacity to tolerate 1.2 mM Cd, Cr after which biochemical defenses declined. Increased activity of glutathione reductase and superoxide dismutase were well documented in 1.2 mM and 1 mM Cd, Cr treated plants respectively. Overexpression of ascorbate peroxidase, superoxide dismutase and glutathione reductase was evident by the appearance of additional bands with respect to control plants which would provide acute detoxification capacity of the plant to cope up with gradual increasing Cd, Cr contamination. Conclusion: This newly emergent Cd and Cr tolerant plant which can thrive well in highly Cd, Cr contaminated soil under field condition is thought to have the potential for phytoremediation of multiple metal contaminated sites of major polluted cities.
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An attempt has been made to compare the effects of conventional phytohormones like IAA, NAA, BAP to the recent hormones viz., JA and SA in callus induction in blackgram using hypocotyl as explant source. Instead of testing the hormone individually, a combination of hormones was used to induce callus and organogenesis. A significant callusing response was noticed in MS medium supplemented with 0.5 ppm of 2,4-D and 1 ppm of IAA. Likewise, Salicylic acid at 1 ppm induced high percentage of callus induction proving its efficiency in inducing the root formation. Jasmonic acid induced a high percentage of callus induction at 1.5 ppm and greater rooting response than SA. Organogenic callus was observed at JA and SA supplementation. The combination of NAA, BAP and SA showed that 0.75 & 1.5 ppm of NAA, 1 ppm of BAP and 0.5 ppm of SA showed a better response in culture medium. Thus, the combination of these hormones seems serve as efficient growth supplements for in vitro culture of many agricultural crops.
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The effects of NO 3 - nutrition on iron deficiency responses were investigated in Arabidopsis thaliana . Plants were grown with or without 5 µM Fe, and with NO 3 - alone or a mixture of NO 3 - and NH 4 +. The results indicated that, NO 3 - nutrition induced higher dry matter production, regardless the Fe concentration. Fe deficiency reduced growth activity, photosynthetic pigment concentration and Fe content of plants, whatever the N forms. This decrease was more pronounced in plants grown with mixed N source; those plants presented the highest EL and MDA and anthocyanin contents compared to plants grown under Fe sufficient conditions. In iron free-solutions, with NO 3 - as the sole nitrogen source, enhanced FC-R activity in the roots was observed. However, in the presence of NH 4 +, plants displayed some decrease in in FC-R and PEPC activities. The presence of NH 4 + modified typical Fe stress responses in Arabidopsis thaliana plants.
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Environmental cues play important roles in the regulation of an animal’s physiology and behavior. In the present study, we performed a factorial experiment (temperature/photoperiod) in which Tupaia belangeri was acclimated to different photoperiods (long photoperiod, 16L:8D; short photoperiod, 8L:16D) and temperatures (warm, 30 oC; cold,5 oC) to test the hypothesis that photoperiod, temperature, or both together can trigger changes in energy budgets and endocrine hormones concentrations. The results showed that temperature, photoperiod had a significant effect on energy intake, and digestible energy intake. Both short photoperiod and cold caused animal's gross energy intake to increase by 25.6% and 89.1 %, and caused digestible energy intake to increase by 24.1% and 83.5% respectively compared with that of the initial, but there was no significant interaction between photoperiod and temperature on energy intake and digestible energy intake. Temperature had significant effect on serum thyrotropin (TSH) concentrations, serum leptin level, photoperiod had a significant effect on TSH and melatonin. The present results suggested that T. belangeri adapt cold stress or short photoperiod by increasing energy intake, and may be regulated by endocrine hormones. Furthermore, leptin and melatonin seem to be involved in the regulation of body mass and energy balance in T. belangeri .
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Innate immunity provides first line defense in all animals against pathogens and parasites. There is seasonal variation in pathogen prevalence and disease because of the seasonal lifecycle of the parasite and due to annual variation in the infectivity of pathogens. Organisms face seasonal stress by regulating their internal physiology, i.e. by secreting hormones. Melatonin and sex steroids contribute to the seasonal redistribution of immunological activity including winter-time up-regulation of some immune responses, and reproduction-related immunosuppression. Present study aims to understand seasonal variation in splenocyte innate immune response in the fresh-water snake, Natrix piscator . Reptiles represent the pivotal phylogenic group as they were the ancestor of both birds and mammals and they are the only ectothermic amniotes providing the key link between ectothermic anamniotic fishes and amphibians, and endothermic amniotic birds and mammals; a greater study of reptilian innate immune response will provide important insights into the evolutionary history of vertebrate immunity. Animals were mildly anaesthetized and the spleen was isolated aseptically. Spleen was used for calculating splenosomatic index, cellularity and macrophage phagocytosis. Spleen size has a trend to be high in autumn and winter months and low in spring and summer, though data were not significant. Spleen cellularity was recorded high in winter months and again in September; while it remained low during rest of the year. No definite pattern was observed in phagocytosis by splenic macrophages. The percent phagocytosis varied between 42 to 60 %, being highest in month of February. It is concluded that seasonal variation in splenocyte immune response provides a mechanism that suites best to the organism and which might coincide with the pathogen prevalence. Seasonal cycle of immune response is helpful in understanding the disease processes in animals and the direct implication of this study could be utilized for the endangered species living in captivity.
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The effects of two superabsorbents (natural-bentonite) and (synthetic-A 200) on the chlorophyll fluorescence index, proline accumulation, phenolic compounds, antioxidant activity and total carbohydrate in lettuce ( Lactuca sativa L.) was evaluated. For this purpose, a factorial experiment using completely randomized design with superabsorbents at 3 levels (0, 0.15, 0.30 w/w%), drought stress at 2 levels (60 and 100% of field capacity) and 4 replicates was conducted. Results showed that photosystem photochemical efficiency (Fv/Fm) II under drought stress (60% FC) as well as lower levels of bentonite superabsorbent polymer reduced. The minimum and maximum proline content were obtained in 0.3% bentonite, 100% FC and 0 benetonite, 60% FC, respectively. The lowest and highest phenolic compounds was corresponded to the highest levels in both super absorbents and control respectively, so that the super absorbent and bentonite, reduced phenolic compounds by 62.65 and 66.21% compared to control. 0 and 0.15 wt % bentonite in high drought stress (60% FC) showed the highest and 0.3 wt % bentonite and 100% FC attained the lowest level of antioxidant activity. Control bentonite treatment beds at 60% FC and beds containing 0.3 wt. % bentonite in 100% FC, showed the lowest and the highest total carbohydrate content respectively. Results of this study indicate that bentonite can reduce the negative effects of drought stress similar to artificial super absorbent.
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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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The effects of exogenous abscisic acid and two sulfonamide compounds: Sulfacetamide and Sulfasalazine were studied on tolerance of tomato ( Lycopersicon esculentum Mill. cv. Super chief) under drought stress and compared with abscisic acid effects. Eight-week old plants were treated with ABA (10 and 25 mg/L), Sulfacetamide (25, 50 and 100 mg/L) and Sulfasalazine (25, 50 and 100 mg/L). Solutions were sprayed daily and sampling was done at 0 h, 48 h, 96 h, 144 h and 48 h after re-watering (recovery phase or 192 h). Treated plants showed relatively greater drought tolerance. This indicates that, Sulfacetamide and Sulfasalazine may improve resistance in tomato, like ABA, increasing levels of proline, glycine betaine and malondialdehyde and the activity of ascorbate peroxidase. Daily application of Sulfasalazine and Sulfacetamide during drought stress period was effective in increasing tomato plants tolerance to drought as was ABA.
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The possible involvement of the methylglyoxal and proline accumulation in leaves and roots of three pistachio rootstocks, cv. Sarakha, Abareqi and Bane baghi, pre-inoculated with arbuscular mycorrhizal fungus ( Glomus mosseae ) in response to salt stress was studied during a greenhouse experiment in 2013. Six months old pistachio seedlings were exposed to four salinity levels of irrigation water (EC of 0.5 as control, 5, 10 and 15 dS m -1) for 70 days. Methylglyoxal and proline of the roots and leaves were increased by increasing salt stress. The highest concentrations of proline in leaves and roots were recorded in Abareqi rootstock while the lowest concentration was observed in Sarakhs. In general, a negative relationship was obtained between proline and methylglyoxal concentrations in both tissues especially at two highest levels of salinity. A very strong relationship between salinity and measured biochemical markers were found. The level of both biomarkers were reduced in both tissues and in all rootstocks as the effect of mycorrhizal symbiosis. Root colonization percentage was declined as the effect of salinity in Abareqi and Bane baghi and not in Sarakhs.