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Effects of some environmental variables on urease in germinating chickpea ( Cicer arietinum L.) seed
Статья научная
Enzyme activity is influenced by a large number of factors. Environmental conditions such as pH, temperature, salt concentration, substrate concentration, activators, and inhibitors may change the three dimensional shape of an enzyme, altering its rate of activity and/or its ability to bind substrate. The effects of such environmental factors were evaluated. The optimum pH and temperature of the purified urease were 7.2 and 48 0C, respectively, using urea as substrate. The optimum substrate (urea) concentration for urease was 25 mM. The enzyme showed the highest activity when incubated for 30 min at 48 0C. EDTA, a metal chelator, decreased the enzyme activity significantly. This may be due to the removal of metal ions located on or near the active site. Divalent cations like Ba 2+ and Mg 2+ slightly stimulated the enzyme at a concentration of 1-3 mM whereas Na + and K + produced little or no effect on the activity. Ca 2+ enhanced urease activity by 120.47%, while Pb 2+, Cu 2+, Zn 2+ and Hg 2+ almost completely inhibited the urease activity.
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Статья научная
In order to investigate the changes of plasticity of visceral organs and digestive tract morphology in Apodemus chevrieri which inhabit in Hengduan mountain region, the organ masses and digestive tract which include the changes of heart, lung, liver, spleen and kidney as well as the length and weight of stomach, small intestine, large intestine and cecum were measured during cold and warm acclimation. The results showed that the weight of heart and liver of cold acclimation group were obviously higher than that of warm acclimation group. The weight and length of small intestine showed significant differences between two groups. All of the results indicated that A. chevrieri maintain their normal life activities by increasing the weight of related organ masses and adjusting the weight and length of small intestine under cold temperature.
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Статья научная
The tomato, a genus of Lycopersicon, is cultivated worldwide for fruit. It is an important gastronomic ingredient and an important source of income for small farmers in Mali. However, its production faces a number of phytosanitary constraints that are still poorly understood. Among phytosanitary problems, bacterial wilt, caused by R. solanacearum , is proving to be the most dangerous and devastating of all tomato crops in Mali. The aim of this study is to contribute to the improvement of tomato production in Mali by identifying tomato varieties tolerant to R. solanacearum and adapted to the growing periods. To achieve this objective, trials under artificial and natural infestation conditions with 12 tomato genotypes during three periods were conducted at the Sotuba research station from December 2018 to December 2019. Analysis of variance revealed no significant difference between the two strains tested. Both strains were more severe, especially in period 2 of the experiment. The Caraïbo variety was the most susceptible to both strains, with an average severity rate of 2.8 (≈3) and the most stress-susceptibility index (0.69). The varieties Carioca and SF-83-61 were the most productive in both experimental conditions. With average yields ≥ 3.5 t/ha under artificial infestation conditions and ≥ 6 t/ha under natural conditions. In contrast, the Roma and Rossol varieties recorded the lowest yields. To minimize R. Solanacearum damage and improve field yields at all cropping periods, the SF-83-61 and Carioca varieties may be recommended for release in areas where R. Solanacearum , responsible for bacterial wilt, causes significant damage in tomato crops after confirmation tests.
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Статья научная
The present study was aimed investigating the effect of water deficit and chitosan spraying on osmotic adjustment and soluble protein of cultivars castor bean under field condition. experiment was carried out as a split factorial based on randomized complete block design with three replications. The results showed that water deficit caused increase a significant (P
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Effects of water stress on rice production: bioavailability of potassium in soil
Статья научная
Water demand in agriculture, municipal, and industrial purposes is increasing rapidly which will pressure on future demand in agriculture. To justify less water use in rice production, we produced rice under different water levels (DWLs) and justified potassium bioavailability. There were five DWLs were employed in this experiment. Besides measuring yield and yield parameters, relative water content (WRC) and chlorophyll content in leaves, soil pH and bioavailability of potassium (K) in soil solution were measured. Yield and yield parameters showed insignificant difference under DWLs. Different water levels did not affect weekly data of chlorophyll content and RWC in leaves. But chlorophyll content and RWC in leaves were significantly higher in week 6 or 9 than week 3. Different water levels did not affect soil pH. Our results suggest that rice can be produced under low water input without affecting yield and yield parameters and K bioavailability in soil.
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Efficiency of priming methods in crop establishment of ginger (Zingiber officinale Rosc.)
Статья научная
The present research work was conducted to evaluate the effect of different priming methods on Zingiber officinale Rosc. variety Karthika. Hydropriming was done by immersing the ginger rhizomes in distilled water for varied time durations (6, 12, 24, 36 and 48 hour), and for halopriming different concentrations (50mM,100mM, 250mM and 500mM) of sodium chloride (NaCl) solution was used for different time durations (6, 12, 18 and 24 hour). The primed plants showed fast germination than unprimed ones. The germination percentage of haloprimed (50 mM NaCl for 24 hour) plants was 89.22% and in hydropriming it was 90.33% (24 hours). But in the case of unprimed (control) plants, the germination percentage was only 55.11%. The present study showed that the optimum time duration for priming in ginger was 24 hours. In halopriming, the growth was highest in 50 mM NaCl for 24 hours. The carbohydrate content and photosynthetic pigment content were highest in primed plants when compared to unprimed plants.When comparing both priming methods, the haloprimed plants showed highest chlorophyll content and carbohydrate content than the hydroprimed ones. But, regarding the yield, hydroprimed plants produced more tillers and thus more yield. Since, ginger is cultivated for mainly for the rhizomes, among the two priming methods investigated, hydropriming was found to be more promising than halopriming in terms of yield.
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Статья научная
Worldwide warming is anticipated to have a typically terrible impact on plant development because of the harmful impact of excessive temperatures on plant improvement. Plants' diversity and productivity are adversely suffering from abiotic environmental factors. Thermal /heat stress is now becoming the main concern for plants everywhere, Major reason behind this is sudden changes in weather and climate which affects medicinal plants around the world and will eventually cause the destruction of some key species. The growing risk of climatological extremes such as very excessive temperatures might result in a catastrophic lack of crop productiveness and bring about extensive famine. Within the boom situation of plant life, several secondary metabolites are produced with the aid of them to serve a ramification of cell capabilities vital for physiological approaches, and the latest growing proof has implicated stress reaction. The medicinal plants comprise bioactive PSNPs, which perform a key role in plant life with the altering environment and stress condition. Within past decades, various studies advertised the healing properties and biological activities of medicinal plants. Excessive levels of pressure in medicinal vegetation exploitation caused by abiotic stress outcomes with the production of ROS inside the cell chambers of a plant cell which ultimately have a tremendous effect on secondary metabolite production. In this article, we have focused on what is the role of secondary metabolite and ROS generation in protecting the plant under the high stressful condition of heat.
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Статья научная
Rauwolfia serpentina (Apocynaceae) is a woody perennial shrub and important medicinal plant. Due to increased interest by both the scientific community regarding the medicinal uses of this plant species, a protocol for in vitro callus induction of Rauwolfia has been developed due to low germination rate (15%-20%). The leaf and stem explants were transferred to MS medium containing different combinations of plant growth hormones; 2,4-dichlorophenoxyacetic acid (2,4-D) + 2-benzyl amino purine (BAP).The concentration of 2,4-D (2.0mg/l) + BAP (1.0 mg/l) produced better results for callus induction in both leaf and stem explants. The least results were recorded in callus induced from leaf explants under the influence of 2, 4-D (2.0 mg/l) and BAP (1.5 mg/l). The present investigation aims to increase the phenolic content in vitro responsible for the antioxidant activity of Rauwolfia. Thus salinity stress has been applied in vitro to increase the phenolic acid content and various enzymes such as SOD (superoxide dismutase) and PAL (Phenyl alanine ammonia lyase) has been studied. The phenolics content was more in leaf callus at moderate salinity level of 15 ppm compared to control and other treatments at 10ppm and 20 ppm. There was increase in total phenolic acid content and antioxidant activity of Rauwolfia under moderate salinity. Result of the experiment showed that the SOD activity was highest at 20ppm followed by 15 ppm and 10 ppm salt treatment. Activities of PAL in the callus increased progressively with the increasing salt concentrations. Increased PAL activity in the leaf callus was linearly and positively correlated with increasing NaCl concentrations and the peak activity in the leaf callus was observed at NaCl concentration of 20 ppm.
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Статья научная
This paper is the first in a series reporting a study on the effects of different concentrations of insecticide, Endosulfan (0-600ppm) was premeditated on 5th day after insecticide exposure with respect to growth rate, pigment composition and photosynthetic activity of Azolla microphylla under laboratory conditions which become non-target organism in the rice fields. Endosulfan inhibited the relative growth rate, pigment content and photosynthetic O2 evolution. Phycocyanin was main target followed by carotenoid and total chlorophyll. Significant increase in pigment, flavonoid and Anthocyanin was noticed after six days of treatment. In contrast to the photosynthetic activity, the rate of respiration in Azolla microphylla was increased significantly. Our results show that Endosulfan at normally recommended field rates and intervals are seldom deleterious to the beneficial and Eco friendly Azolla microphylla and their activities and thus in turn suppress plant growth and development. Phytotoxity of Azolla microphylla can be minimized by restrictions on application, timing, method and rate of application.
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Enzyme activity and seedling growth of soybean seeds under accelerated aging
Статья научная
Seed aging is the main problem of seed storage. Changes of bio-chemical and reduction of seedling growth are consequence of seed deterioration. An experiment was conducted to evaluate the effects of accelerated aging on soybean seed germination indexes and enzyme activity. Seeds were incubated in closed plastic boxes for the accelerated aging treatments. Three accelerate aging regimes were performed by placing seeds at 41°C and relative humidity (RH) of 90-100 % for 0, 2, 4, 6 and 8 days periods. Our results showed that increasing aging duration resulted higher reduction in germination characteristics, catalase and ascorbate peroxidase. Germination percentage, means time to germination, germination index, normal seedling percentage and enzyme activity decrease significantly.
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Enzyme activity, hormone concentration in tree shrew (Tupaia belangeri) during cold acclimation
Статья научная
Environmental factors play an important role in the seasonal adaptation of body mass and thermogenesis in wild small mammals. The tree shrew (Tupaia belangeri), is a unique species of small mammals which is origin of island in the Oriental realm. The present study was to test the hypothesis that ambient temperature was a cue to induce adjustments in body mass, energy intake, metabolism, uncoupling protein 1 (UCP1) in brown adipose tissue (BAT), and other biochemical characters of T. belangeri during cold exposure about 21 days. Our data demonstrate that cold acclimation induced a remarkable increase in body mass, a significant increase in energy intake and metabolic rate, and high expression of UCP1 in BAT of T. belangeri. Cold acclimation induced an increase in cytochrome c oxidase (COX) and Thyroidhormones (T3/T4). These data supported that T. belangeri increased the body mass and increased energy intake and expenditure under cold acclimation. Increased expression of UCP1 was potentially involved in the regulation of energy metabolism and thermogenic capacity following cold acclimation. And it through changes in enzyme activity and hormone concentration under cold acclimation, and suggested temperature changes play an important role in the regulation of thermogenic capacity in tree shrew.
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Статья научная
Background: The objective of the present study was to investigate the ability of butanolic extract from leaves of Chrysanthemum fontanesii, vitamin E and C to modulate ethanol-Induced toxicity and oxidation damage in maternal and fetal tissues of mice. Butanolic extract from leaves of Chrysanthemum fontanesii (200 mg/Kg per day), vitamin E (100mg/Kg per day) and C (8.3mg/Kg per day) were administered by gavage to groups of pregnant mice from the 6 th to 17 th day of gestation. A number of animals received plant extract, vitamin E and C, also treated with an oral administration of ethanol (0.02ml/g of 25% v/v absolute ethanol in water per day) in same conditions. On day 18 of gestation, pregnant mice were killed, fetus, placenta, fetal liver, liver, kidneys and brain were removed, homogenised and used for determination of lipid peroxidation (LPO) using TBARS method. Embryotoxicity was assessed by counting the number of live and dead fetus and growth retardation. Results: Severe alterations in all biomarkers were observed after injury with ETOH. ETOH produced significant decreases in fetal weight and significant increases in embryolethality and lipid peroxidation relative to control values. Treatment with Chrysanthemum fontanesii extract, vitamin C and vitamin E resulted in markedly decreased embryolethality and fetal growth retardation, while increased fetal weight were observed. Conclusion: The butanolic extract from leaves of Chrysanthemum fontanesii, vitamin E and C protected against ethanol induce fetal and maternal toxicity as revealed by the decrease in the extent of lipid peroxidation. So that butanolic extract from leaves of Chrysanthemum fontanesii posses in vivo antioxidant properties.
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Euhalophyte eryngium maritimum L.: the microstructure and functional characteristics
Статья научная
The microstructure of the leaf surface, lipids composition, pigments spectrum, biological and photosynthetic activity, and hormones status of euhalophyte Eryngium maritimum L., one of the most salt-tolerant plants, were studied. It was shown that the existence in saline and dry soils is provided among others adaptive mechanisms by specific microstructure of leaf, adaxial and abaxial surfaces of which have well-developed cuticle and stomata slit placed below the surface of the epidermis. The presence of a large amount of saturated fatty acids provides decrease of membrane permeability and better resistance against soil salinity. The key role in photosynthetic activity is played by chlorophyll a. At the same time a high amount of carotenoids (as compared with amount of chlorophylls) points out that these pigments have a light-collecting function and could transfer an additional energy to chlorophylls. The data from thermoluminescence analyses showed a possible inhibition of recombination reactions in PS II by the assumed saline concentration in plant tissue. Besides, the fluorescence measurements indicate reduced efficiency of photosynthetic reactions. The high level of active ABA is correlated with salt tolerance and ability to survive and grow in stress conditions. The high level of conjugated form of IAA demonstrated that activity of this hormone is limited.
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Статья научная
To evaluate the freezing resistance and genetic diversity in barley physiological traits, molecular markers and their relationship in 20 barley genotypes were assessed in field and greenhouse condition. The analysis of variance showed a significant difference among studied genotypes. The effect of acclimation temperature on prolin content, quantum efficiency of photosystem II, chlorophyll and soluble sugars content were studied as physiological traits. Freezing treatments were -4, -7, -10, -13 and -16 °C temperatures that applied in a 3 replicated randomized complete block design. Then their lethal temperature at which 50% of plant were died (LT 50) was determined. To estimate FSI (Field Survival Index) index, the 20 genotypes were cultured in a separate experiment on field with 3 replications. The results showed negative significant correlation (-0.601) between field survival index and LT 50. Cluster analysis using physiological traits, genotypes of F-A1-1, F-A1-2, F-A2-11, F-GRB-85-5, Sahra, Sahand, Dasht and Makouei were categorized in a distinct group and had a high FSI and low LT 50. Makouei cultivar having LT 50=-17.66 °C and the highest percentage of winter survival in the field, was the most resistant genotype. 10 ISSR markers from 35 primers sequences were selected and used. These 9 ISSR primers produced 50 polymorphic bands. PIC and MI average index for all primers were 0.37 and 1.72 respectively. Cluster analysis of molecular data using Jaccard similarity coefficient categorized the genotypes to four distinct groups. Associations between molecular markers and traits were assessed by multiple regression analysis. Some informative markers related to FSI and also LT 50 was determined. So it may be possible to use these markers for selection of resistant lines or genotypes in breeding programs.
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Статья научная
Background : Stress is a common entity, widely spoken about among the working population, for which a safe and effective remedy is needed. Purpose of the study : To evaluate the clinical effectiveness of Arogh plus a polyherbal formulation, towards stress relieving properties in a randomized clinical trial in volunteers. Results : The clinical benefit of stress was reinforced by way of significant reduction in serum cortisol, increase in total count and reduction of symptoms pertaining to stress in a randomized clinical trial in volunteers carried out at Rohini Holistic Health centre. Conclusion :Arogh plus is an effective formulation in relieving stress and improving the quality of life.
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Evaluation and genetic polymorphism studies of jatropha (Jatropha curcus) for water stress tolerance
Статья научная
Jatropha (Jatropha curcus) is an alternative resource for biodiesel. To boost the rural economy in sustainable manner it is estimated that 30 Million hector plantation may replace current use of fossil fuel. Although Jatropha has an inbuilt ability to grow under water limited conditions, scanty information is available about natural genetic variation for water stress tolerance. Three local genotypes from Pune district were collected and initially screened by imparting artificial stress using PEG - 6000. Seedlings were subjected to increasing concentration of PEG - 6000 (30, 60, 90, 120 and 150 gm/l) to study effect on growth parameters. The root growth, number of secondary roots, true leaf expansion at morphological level and palisade mesophyll height, xylem vessel expansion at anatomical level showed drastic negative impact as compared to control. It is worth to note that local germplasm performance was categorized into susceptible group as compared to tolerant genotype [Chattisgadh Selection] indicating need for genetic improvement. These genotypes were further studied at molecular level with RAPD and ISSR markers to amplify genetic variation. Polymorphic bands from Chattisgadh selection genotype are being evaluated for their usefulness as markers for water stress tolerance.
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Статья научная
Cereals in general and millets in particular have been identified as major food crops globally and increase in crop production is required to meet the demands of the ever increasing global population. However, continuous climatic variations or abiotic stresses have led the drastic reduction in food grain yields. In view of affects of abiotic stresses on food crops plants, present study was undertaken to analyze the comparative responses of salinity stresses induced by various concentrations of NaCl (50mM, 100mM, 250mM and 500mM) and sea water (5%, 10%, 15%, 20%, 25%, 50%, 75% and 100%) during seed germination and seedling growth under ex-vitro conditions in kodo millet (Paspalum scrobiculatum L.). After 6-days and 12-days of salinity stress treatments, observations were recorded and after 12-days of treatments, results reveal that salinity stress caused by NaCl-salt concentration (250mM) proves to be very lethal causing strong seed germination and therefore, the mean germination frequency (33% ±0.530 was recorded while further increase in NaCl concentration (500mM) was found to be fully toxic and seed germination frequency was obtained as zero in comparison to control experiment (94% ±0.35). Similarly, in case of salinity stress induced by sea water treatments, 25% of the sea water concentration was found to cause strong promotion instead of inhibition and (71% ±0.17) of the seeds could exhibit promotion in germination frequency and further increase in sea water concentration (50%) and above was turned out to be fully toxic. Furthermore, during biochemical studies, protein contents in the tissues growing under NaCl-salinity stresses at (50mM, 100mM and 250mM) were estimated and significantly it was found to decline with the increase in concentration of NaCl-salt stress solutions. After 12th days of treatments, protein contents were found to be minimum (198.2 mg/g) in the tissues that were growing in high concentration of NaCl (250mM) solution than the control solution (476.4mg/g) grown tissues.
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Статья научная
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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Evaluation of antiulcer activity of Crateva magna (Lour.) Dc in Wistar albino rats
Статья научная
The Antiulcer activity of aqueous leaf extract of Crateva magna (Lour) DC. was investigated on Ethanol induced ulcer model and Aspirin induced model in wistar rats. In both models the common parameters determined was ulcer index, ulcer score, gastric pH, free and total acidity, Antioxidant parameters such as glutathione peroxidase, superoxide dismutase, lipid peroxides. The aqueous leaf extract of Crateva magna (Lour) DC. dosage 150, and 300 mg/kg produced significant inhibition of gastric lesion induced by Ethanol induced ulcer and Aspirin induced ulcer. The aqueous leaf extract of Crateva magna (Lour) DC. dosage 150, and 300 mg/kg showed significant reduction in free acidity, total acidity, and ulcer index as compared to disease control. The study indicates that aqueous leaf extract of Crateva magna (Lour) DC. have potential antiulcer activity in both models. These results indicated that Crateva magna (Lour) DC. displayed an antiulcerogenic effect due to its cytoprotective activity. Besides antioxidant potential of plant extract scavenged the free radicals produced by Ethanol induction, Aspirin induced ulcer and healed the ulcers.
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Статья научная
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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