Статьи журнала - Журнал стресс-физиологии и биохимии
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Статья научная
The effect of low temperature (2 ºС, 7 days) on the content of soluble carbohydrates in the leaves and oxidative activity of isolated mitochondria from the etiolated plants of winter wheat ( Triticum aestivum L.) and winter rye ( Secale cereale L.) has been studied. This paper describes the effect of low temperature on the distribution of the respiratory pathways in the isolated mitochondria from etiolated leaves of winter wheat and rye that are different by resistance to cold. With using the different oxidation substrates (malate, malate + rotenone, succinate, NADH and NADPH), we identified changes in the oxidative activity of winter wheat and rye mitochondria. In this work, the dependence of the functioning of cyanide-insensitive oxidase and rotenone-insensitive NAD(P)H dehydrogenases in the isolated mitochondria of winter cereals from content of the soluble carbohydrates is discussed.
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Diurnal influence on phenol compound dynamic into leaves of medicinal plants
Статья научная
Content of phenol compound in leaves of Alchemilla subcrenata, Achillea asiatica, Taraxacum officinale, Veronica chamaedrys was researched. The dynamics of alteration of phenol compound content during round the clock in October was determined. The dependence of phenol compound substance in leaves of study plants on temperature was shown.
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Статья научная
Gas exchange and chlorophyll fluorescence analysis were carried out to investigate the diurnal variations in photosynthesis in leaves of rice (Oryza sativaL.). Leaf CO2photosynthetic rate (Pn) showed a bimodal diurnal pattern and midday depression in Pn was observed at 13:00 h. Depression in Pn at midday was mostly attributed to stomatal limitation since the reduction in Pn was followed by the significant reduction in stomatal conductance (Gs). Midday depression in Pn was found to be associated with reversible inactivation of Photo-system II (PS II) reaction centers and increase of photo-inhibition in response to high intensity as evidenced by the maximum efficiency of PS II (Fv/Fm) decreased with increase of light intensity from 6:00 h to 16:00 h of a day. The minimal fluorescence (Fo) gradually increased with increasing light intensity and reached its highest value at 13:00 h and on contrary the maximal fluorescence (Fm) decreased and reached its lowest value at 13:00 h. Quantification of several chlorophyll fluorescence parameters (JIP-test) like area above the fluorescence curve between Fo and Fm, phenomenological energy fluxes like electron transport per cross section (ETo/CS), active PS II reaction center per exited cross-section (RC/CSo) and performance index (Pi) were low in early morning, increasing with time and reaching a maximum at 9:00 h subsequently decreasing and reaching a minimum value at 13.00 h. On contrary the dissipation per cross-section (Dio/CS) gradually increased with increasing light intensity and reached its highest value at 13:00 h. It is likely that PS II down-regulation and heat dissipation co-operated together to prevent the chloroplast from photo damage.
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Статья научная
From the ecological and economic point of view Agropyron elongatum, among perennial grasses, has a special place. This study was conducted to determine the most appropriate seed priming treatment and whether after a temporary stress removal, primed seeds have a higher recovery efficiency compared with unprimed seeds? In this research, seed was treated with different osmo and hydro priming and evaluated their effect by conducting germination test under drought stress (-1.2 and -1.4 MPa PEG) and recovery test. Hydro-primed seeds at 10 °C at all times (12, 24, 36 and 48 h) during priming; most indices of germination significantly improved compared to unprimed seeds. Also, seeds treated with osmopriming at both temperatures (10 & 15 °C) and all times of priming compared to unprimed seeds in the stress level of -1.2 MPa, the germination characteristics were improved. However, by increasing the potential of stress, few priming treatments have been able to maintain their superiority. It appears that priming can partially be effective on stress resistance and if the stress threshold is slightly higher than expected (this threshold for the Agropyron seeds in this study was -1.2 MPa) cannot have a noticeable effect on resistance to drought stress and can even be harmful too. All treatments which were placed in stressful situations and then moved to fresh water, showed a variety of recovery responses. As we viewed, primed seeds with a solution of -0.6 MPa urea for 12 h at 15 °C and followed by PEG solutions (-1.2 and -1.4 MPa) for 5 days and subsequently moved to fresh water conditions, had higher performance compared to unprimed seeds (P
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Статья научная
A pot experiment was conducted to evaluate the effect of grain presoaking in kinetin (0.1 mM), spermine (0.3 mM) and their interaction on yield components and biochemical aspects of yielded grains of wheat plants irrigated with 25% seawater. Seawater induced marked reduction in biochemical aspects of yielded grains especially carbohydrates content, nitrogenous constituents, total protein and nucleic acids contents as well as proline and organic acids (citric and keto acids) contents. Conversely, seawater stress increased phosphorus and ions (Na +, K + and Cl -) contents. Application of kinetin or spermine appeared to mitigate the effect of seawater stress on wheat yield and the biochemical aspects of yielded grains. The effect was more pronounced with kinetin + spermine treatment.
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Статья научная
A pot experiment was conducted to evaluate the beneficial effect of foliar application of glycine betaine (10mM), grain presoaking in salicylic acid (0.05 M) and their interaction on drought tolerance of two wheat ( Triticum aestivum L.) cultivars (sensitive, Sakha 94 and resistant, Sakha 93). Osmotic pressure, some osmolytes concentration and grain yield were determined. Water stress caused an increase in osmotic pressure, proline, total soluble nitrogen, total soluble sugars, organic acids, ions (Na +, K +, Ca +2, Mg +2 and Cl -) content as well as Na +/K + ratio in cell sap flag leaves of both wheat cultivars. The resistant variety had higher values of osmotic pressure, proline, organic acids and ions content than the sensitive one. On the other hand, water stress induced marked decrease (P
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Drought and UV stress response in Spilanthes acmella Murr., (tooth-ache plant)
Статья научная
In the present investigation, experiments were conducted to investigate the growth, morphological, anatomical and biochemical responses of to UV and drought stresses in Spilanthes acmella (toothache plant). Results were shown that both UV and drought treatments retarded plant growth. Although there was no significant difference in the internal structure of leaf and stem. Morphometric changes such as curling of leaves and shiny surface due to waxy coatings were noticed in plants grown under UV radiation however these changes were absent in water stressed plants but yellowing was observed in the entire leaves. Chlorophyll content and relative water content in leaves were significantly affected by UV and drought. Relative water content markedly increased in UV treated plants and reduced in drought. In UV treated plants chlorophyll a, chlorophyll b and total chlorophyll contents were considerably decreased than the drought treated plants. The carotenoid, flavonoids and anthocyanins concentration increased in both treatments. Changes in contents of antioxidative metabolites under the stresses were observed. Free proline and MDA accumulations also showed significant increase in drought treatment than in UV treatment. During drought condition the catalase activity decreased as compared with the control plant whereas UV treated plants showed increase in the catalase activity.
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Drought stress and its impact on protein in three species of Vitex
Статья научная
Drought is one of the most important natural phenomenon which affects on plant growth. When drought stress is imposed different molecular and biochemical responses took place in the plants. The protein profile of three species of Vitex (Vitex trifolia L., Vitex altissima L. and Vitex negundo L.) under normally irrigated condition and severe drought plants was analyzed through SDS-PAGE. Drought stress significantly affects proteins in plants when compared the normal conditioned plants. Several new protein bands were identified in the stressed plants. It seems that Vitex species can be adapted to drought stress conditions. Hence it was concluded that number of new proteins were synthesized in stressed plants for their adaptation in the stressed conditions. These proteins could be used as markers in identifying the stressed plants.
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Drought stress in plants: effects and tolerance
Статья обзорная
Water is the catalyst of life and plays a profound role in plant physiological processes ranging from photosynthesis to intermolecular interactions through a hydrophobic bond. Because of the alterations due to changing environmental conditions, the plants are continuously exposed to a lack of optimum water availability, leading to impaired growth and disturbance in water transport and uptake. Drought is a prominent environmental factor that triggers various plant processes from morphological, physiological, biochemical, and molecular. Plants portray an array of drought tolerance mechanisms; these responses differ based on the type of plant species and may involve the functions of various stress genes. Reduction in plant growth and productivity due to stomatal closure affects photosynthetic efficiency, altering membrane integrity and several enzymes involved in adenosine triphosphate synthesis. Plants exhibit a range of drought tolerance mechanisms and undergo several phenological, morphological, physiological, biochemical, and molecular adaptations at the cellular, subcellular and whole plant levels. Also, drought stress induces the production of reactive oxygen species at the cellular level and is strongly protected by the increase in the enzymatic and non-enzymatic antioxidative system. This chapter/ review provides a glimpse of the effects and tolerance strategies adapted by the plant under drought stress.
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Drought stress in pulse crops: consequences and mitigation options
Статья обзорная
Pulses are essential for global food security and nutrition, serving as crucial sources of protein, vitamins, and essential micronutrients for humans. They are well-known for their high protein levels, their ability to enhance soil fertility through nitrogen fixation, and their role in sustainable farming practices. Nonetheless, climate change has exacerbated the frequency and intensity of droughts around the globe, posing significant problems for pulse cultivation. The extent of yield loss in pulse crops can differ between species and even among varieties within a species, depending on the intensity of drought stress and factors such as growth stages, soil types, and agro-climatic conditions. Understanding how drought stress impacts pulses and investigating effective mitigation strategies to ensure food security amid changing climate conditions is vital. This review article compiles reliable information from first-hand sources to highlight the detrimental effects of drought stress on the growth, yield, and physiological activities of pulses. It also recommends mitigation strategies, including agronomic practices, the use of phytohormones, and plant breeding techniques, to reduce yield losses caused by drought. Additionally, it is advised to enhance farmers' awareness of drought stress management and for the government to provide support to growers to help them effectively tackle this challenging issue.
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Drought tolerance induced by foliar application of abscisic acid and sulfonamide compounds in tomato
Статья научная
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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Dynamics of Pinus sylvestris L. needles activity in Predbaikal’ye forests
Статья научная
The study was aimed to analyse changes in peroxidase activity of common pine needles throughout the year. The needles of the 1-st, 2-nd and 3-d years were collected. Total activity of guaiacol-dependent peroxidase was determined. Minimum peroxidase activity is observed in January and February. In March intense overall activation of peroxidase is observed in the needles of all ages, which might be related to spring enhancement of physiological processes and activation of metabolism. Autumn period is characterized by more or less high activities of guaiacol peroxidase from September till November, which is related to its participation in stress-adaptation to low temperatures in winter. Peroxidase activity changes depending on the season of the year. Needles of different age are characterized by their own peroxidase activity level in various time periods.
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Статья научная
Xerophytic cereal Stipa krylovii Roshev is interesting as a relic with extensive capabilities to adapt to severe climatic conditions of Eastern Zabaikal’ye, which allows it to occupy a vast areal. The species under study is characterized by distinctive ecological-biological peculiarities, which are underpinned by not only distribution, but historical establishment of the species. The primary goal of the research was to study ecological-biological peculiarities of adaptation of wild cereal Stipa krylovii to the habitat in Eastern Zabaikal’ye. According to the observations, Stipa krylovii is characterized by late development rate coinciding with the period of optimal heat and moisture availability. Seed embryos have a well-developed scutellum, distinct structures and well differentiated embryo axis. The studies identified no lateral or secondary roots in the cereal. In nature, seeds of S. krylovii are characterized by profound organic peace period, which persists in the course of sprouting under optimal conditions. Peace period of S. krylovii caryopses is likely to be due to the presence of sprouting inhibitors and is overcome in moist autumn period. Seed viability was determined under various soil moisture parameters up to its complete water capacity; the impact of moisture content on seed sprouting rate was studied. The results of the tests on caryopses sprouting with various moisture content demonstrated that at minimum moisture content (10%) S. krylovii forms epidermal hairs on coleorhiza; 30% of soil water content is enough for growth activation, viability and sprouting rate of this cereal, which is due to its xerophytic nature. This morphological peculiarity is likely to ensure in nature sprouting of these species in early spring, when soil contain minimum water. Intensity of the initial growth was determined by a number of parameters: rate of change in linear growth of trunk and root parts of the embryo, growth of dry substance of plantlets and roots (4-th and 6-th days of sprouting). Thus, characteristic morphological peculiarities in cereal structure play a certain role in adapting sprouting seeds to moisture deficit; so embryos of the species may be supposed to have their morphological mechanisms of regulating moisture absorption. Study of individual embryo parts demonstrates potential ecological-biological abilities of embryos to sprout with lack and excess of moisture.
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Статья научная
Background : Cascabela thevetia (L.) Lippold, a popular member of family Apocynaceae, (Yellow Oleander), contains pharmacologically active constituents include terpenoids, a-vonoid, steroids and glycosides in seeds. This plant is being the preferred tool for suicides in villages of India.
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Статья научная
Abiotic stresses, such as temperature, drought and salinity are serious threats to agriculture. Temperature stress is the primary cause of crop loss worldwide, reducing average yields for most major crop plants. In present study role of 24-epibrassinolide in three Brassica species ( B. carinata, B. juncea and B. napus ) on lipid peroxidation and proline under temperature stress was investigated. Seeds were given temperature treatments (4, 14, 24, 34 and 44°C) for 5 hours alone or in combination with EBR (10 -11, 10 -9 and 10 -7 M). Temperature stress whether low and high causes stress in terms of lipid peroxidation. High temperature causes more stress as compared with low temperature stress, as level of temperature stress rises increase in the membrane damage was observed. However the seeds treated with the EBR shows positive effect as there is decrease in the lipid peroxidation in terms of MDA content. Accumulation of proline was also observed in all temperature stress in all three Brassica species. Application of EBR at all concentrations causes significant increase in the proline content as compared with control and untreated.
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Статья научная
Legumes play very important role in agriculture as they form associations with bacteria that, fix nitrogen from the air. French bean is used in all over of the world as an edible vegetable crop. Seed ageing 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 ageing on French bean seed germination and vigour indexes and hormone activity. Seeds of Phaseolus vulgaris L. were treated by accelerating treatments for 4, 6 and 8 days and the influence of ageing, GA3 (20, 30 & 40 ppm) and IBA (5, 10 & 20 ppm) under different concentrations in 8 days aged seeds of French bean were observed. Various parameters were taken for consideration such as germination percentage, along with the mean daily germination, speed of germination, dry weight of seedling and vigour index-I & II. Seeds of P. vulgaris showed 96.66% germination without any treatment (control condition) but during the exposure of specific temperature (42°C) with 100% relative humidity, seeds showed 30% reduction in germination just after 8 days of ageing treatments. While the treatment for 4 and 6 days did not show any remarkable changes in percent germination. So the seeds treated for ageing for 8 days were taken to enhance the germination by treatment of different hormones i.e. GA3 and IBA with different concentrations. Aged seeds treated with GA3 20 ppm showed high germination (82.99%) in comparison to GA3 40 ppm (66.32%).
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Статья обзорная
Copper (Cu) and manganese (Mn) are essential micronutrients for plants, but toxic at high concentrations. Responses of rice (Oryza sativa L.) and sunflower (Helianthus annuus L.) to toxic concentrations of Mn and Cu (up to 100 µM) were studied under three light intensities including low (LL, PPFD=100), intermediate (IL, PPFD=500) and high (HL, PPFD=800) light intensities in hydroponic medium. Rice plants showed higher susceptibility than sunflower to both heavy metals concerning dry matter of shoot and root. Growing under higher light intensity strengthened the effect of Cu toxicity while ameliorated that of Mn, the latter was attributed to the lower Mn accumulation of HL plants in both shoot and root. Chlorophyll content of leaves was influenced negatively only by Cu treatment and that at the highest concentration in the medium (100 µM). Similar with growth results, reduction of net assimilation rate (A) was higher in HL than LL plants treated by excess Cu, but in contrast to growth response, reduction was more prominent in sunflower than rice. Excess Mn-induced reduction of A was similar between LL and HL plants and was greater in sunflower than rice. Reduction of A was partly attributable to stomatal limitation, but non-stomatal mechanisms were also involved in this reduction. Copper and Mn treatment did not change the optimal quantum efficiency of PSII in dark-adapted chloroplasts (Fv/Fm ratio), but Fv/F0 was influenced particularly by Cu treatment, the reduction was higher in rice than sunflower and in HL compared to LL plants. Regarding excess Cu and Mn-mediated alterations in chlorophyll concentration, Fv/F0 and Tm values, it was suggested that, Cu and Mn toxicity depress the leaf photosynthetic capacity primarily by causing a significant alteration of the composition and functional competence of the photosynthetic units rather a reduction in the number of photosynthetic units (PSUs) per unit leaf area.
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Статья научная
Heavy metals are the elements that are present in the environment naturally, with the development of industries in the world, there is a drastic increase of heavy metals in the biosphere. Among the heavy metals, lead (Pb) is the most toxic metal that easily gets accumulated in the soil and sediments. Lead is not an important element for plant growth but it gets easily absorbed and accumulated in different parts of the plant. In this study, Setaria italica (foxtail millet - CO (Te) 7) is treated with different concentrations of lead to evaluate the changes in the morphological growth parameters such as rate of percentage of germination, Tolerance Index (TI) and phytotoxicity. The germination percentage is comparatively greater in the control plant and gradually decreases as the concentration of Pb increases. The length of root and shoot, the amount of fresh weight and dry weight also decrease with the increase in the concentration of heavy metals. The root length and shoot length in the control on the 45th day were 20.2±0.16 and 48.7±0.24 whereas in the maximum concentration of metal (250 mg/kg) it showed a minimum reading of 11.1±0.43 and 27.3±0.33 respectively. The percentage of phytotoxicity increases as the concentration of the metal increases. Tolerance indices decrease as the percentage of phytotoxicity increases.
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Статья научная
Increasing atmospheric CO2 concentration is generally expected to enhance plant growth, allocation and chemical composition of alkaloids in medicinal plants. The response to the elevated CO2 concentrations of various medicinal plants were studied with reference to growth and biochemical changes. Catharanthus roseus is an important medicinal plant which is being cultivated commercially in India for different purposes. It has gained interest from the pharmaceutical industry; the alkaloids vincristine and vinblastine from its sap have been shown to be an effective treatment for leukemia and lymphoma. It has a great importance in studying different parameters of C. roseus. The present study was carried out for growth and bio-chemical changes of C. roseus in different elevated CO2 levels. Open top chambers (OTCs, 3.0 m diameter, 3.0 m in height) were used to expose plants to ambient and elevated CO2 concentration (600 and 900 ppm).The experiment was conducted for five months. Carbon-dioxide enrichment studies in special open top chambers help us in understanding the changes at individual Biochemical changes and plant growth. The bio-chemical analysis revealed that the highest phenol, flavonoid, carbohydrate and tannin were recorded at 600 ppm+rh, and alkaloid was at 900 ppm. In ambient condition the highest protein was recorded in C. roseus. The plant growth revealed that the maximum fresh weight, shoot length and number of leaves were observed in 900 ppm. The maximum number of roots was observed in 600 ppm and the highest root length observed in 600+Rh. In the ambient condition, the above said characters were found to be in the lowest level.
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Effect of Exogenous Trehalose on Physiological Responses of Wheat Plants Under Drought Stress
Статья научная
Drought stress causes physiological changes in plant morphological growth and development. The protective role of trehalose (Tre) was investigated through exogenously applied to seedlings of wheat cv. Sakha 93 plants. Pots experiment were divided into four groups: control, Tre treatment, drought stress and drought stress with Tre treatment. Samples were collected in two stages after 7 and 14 days from drought stress to determine the fresh weight, dry weight, chlorophyll pigments, relative water content, electrolytic leakage, proline, malondialdehyde, antioxidant enzyme activities, and carbohydrates content. Drought stress reduced many growth and physiological characters. It significantly increased specific activities of guaiacol peroxidase (GPX) and ascorbate peroxidase (APX) and significantly decreased the catalase (CAT) activity. It caused significantly increased in the Tre content while reduced sucrose and starch contents. Combination exogenous applied Tre (40 mM) with drought stress improved some growth parameters and photosynthetic pigments. Application of Tre markedly decreased proline and malondialdehyde contents, GPX; APX activities whereas increased CAT activity. Tre treatment appeared increased in the internal Tre content, on the other hand; exogenous Tre maintained the sucrose and starch contents in the seedlings of wheat plants under drought stress. The results concluded that applied Tre alleviated the adverse effect of drought stress on wheat plants by enhancing the antioxidant defense system and conservation of the membrane stability.
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