68 research outputs found

    Regulation of superoxide dismutase activity in soybean plants by inoculating seeds with rhizobia containing nanoparticles of metal carboxylates under conditions of different water supply

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    Soybean is one of the most profitable advanced crops in agricultural production in Ukraine and the world as a whole. Therefore, studies of means of regulation and increase in the adaptive capacity of soybeans in symbiosis with nodule bacteria under the action of unfavourable environmental factors are relevant and should be aimed at the use of complex bacterial compositions involving modern nanotechnological approaches. Nanocarboxylates of ferrum, molybdenum and germanium metals were used as components of rhizobia inoculation suspension for soybean seed treatment to study the effectiveness of their complex effect on the regulation of the activity of the key antioxidant enzyme superoxide dismutase in plants under drought. Various symbiotic systems were used, which included soybean plants and inoculation suspensions based on the active, virulent Tn5-mutant Bradyrhizobium japonicum B1-20 by adding nanoparticles of ferrum, germanium and molybdenum carboxylates to the culture medium in a ratio of 1: 1000. Citric acid was the chelator. A model drought lasting 14 days was created during the period of active fixation of atmospheric molecular nitrogen by root nodules of soybeans in the budding and flowering stages, by means of controlled watering of plants to 30% of the total moisture content. In the stage of bean formation, watering of plants was resumed to the optimal level – 60% of the total moisture content. The control was soybean plants, the seeds of which were inoculated with a suspension of rhizobia without the addition of chelated metals. The following research methods were used in the work – microbiological, physiological and biochemical. According to the results, it was found that when nanoparticles of carboxylates of ferrum, molybdenum and germanium were added to the inoculation suspension of rhizobia, there was an increase in superoxide dismutase activity in root nodules and a decrease in soybean leaves under optimal water supply conditions of plants. This indicates the initial changes in the activity of the antioxidant enzyme in these symbiotic systems, induced by the influence of chelated metals in combination with the rhizobia of the active Tn5-mutant B. japonicum B1-20. Prolonged drought induced an increase in the overall level of superoxide dismutase activity in soybean nodules and leaves, compared to plants grown under optimal watering conditions. The symbiotic system formed by soybeans and B. japonicum with molybdenum carboxylate nanoparticles was the most sensitive to long-term drought exposure, compared to two other soybean-rhizobial symbioses using ferrum and germanium nanocarboxylates. This was manifested in the unstable reaction of the enzyme to the action of drought – suppression or intensification of the level of its activity in the root nodules and leaves of soybeans inoculated with rhizobia containing molybdenum carboxylate nanoparticles. In symbiotic systems with the participation of germanium and ferrum nanocarboxylates, slight changes were revealed in superoxide dismutase activity in root nodules and leaves of plants during drought and restoration of enzyme activity to the level of plants with optimal watering after water stress. It is concluded that the addition to the culture medium of rhizobia Tn5-mutant B1-20 of nanocarboxylates of germanium or ferrum is an effective means of regulating the activity of the antioxidant enzyme superoxide dismutase in soybean root nodules and leaves, which can contribute to an increase in the protective properties and adaptation of plants to the action of dehydration

    Composition of pigment complex in leaves of soybean plants, inoculated by Bradyrhizobium japonicum, subject to metal nanocarboxylates and various-levels of water supply

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    A distinctive feature of legumes is the ability to combine two most important processes: photosynthesis and nitrogen fixation. However, the course of those processes, and therefore seed potential of those crops depend on a number of biotic and abiotic factors, the commonest being drought. Therefore, interest in physical-biochemical resistance of the plant organism to abiotic stress factors is increasing, as well as search for optimum ways to increase its adaptability. Success of adaptation of a plant’s organism to unfavourable environmental factors is known to largely depend on optimal functioning of assimilative apparatus. Some indicators of the condition of the apparatus are the content and ratio of photosynthesis pigments. Therefore, we aimed at determining the reaction of the pigment complex of Glycine max (L.) Merr. plants, grown against the background of optimal and insufficient watering, to inoculation of seeds with rhizobia bacteria Bradyrhizobium japonicum, cultivated using nanocarboxylates of chromium, cobalt, iron, copper and germanium. Research has shown that utilization of germanium nanocarboxylate as a component of inoculative suspension led to the highest content of chlorophylls in leaves of soybean of the studied variants in the blossoming phase during optimal watering, as well as significant increase in the content of carotenoids compared with the control plants regardless of the level of watering. At the same time, this element caused no significant effect on the chlorophyll content in plants grown in drought. It was confirmed that among soybean plants that were in stress conditions (blossoming phase) for two weeks, the highest content of chlorophylls was in leaves of plants grown from seeds inoculated with rhizobial suspension with addition of chromium and copper nanocarboxylates, which caused 25.3% and 22.8% increase in chlorophyll а, 29.4% and 32.3% in chlorophyll b and 26.4%% and 23.8% in them respectively, compared with the control. Furthermore, chromium and copper nanocarboxylates stimulated the content of carotenoids in the same plants, though it was less expressed than after adding germanium nanocarboxylate. The highest content of photosynthetic pigments in plants after the watering was resumed (phase of bean formation) was in cases of applying chromium and germanium nanocarboxylates. It was confirmed that the most efficient way to protect the pigment complex of soybean plants during drought was using chromium and germanium nanocarboxylates as components of inoculation suspension. The results we obtained indicate the possibility of applying chromium nanocarboxylate in the technology of cultivating soybean in the conditions of water deficiency as an effective way to improve biosynthesis of chlorophylls, as well as using germanium nanocarboxyllate as a component that provides a high level of activity of protective mechanisms of the pigment system of soybean, associated with resisting stress caused by water deficiency

    Activity of nitrogen fixation and antioxidant enzymes in symbiotic systems Glycine max – Bradyrhizobium japonicum for complex treatment with lectin and fungicides

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    The dynamics of the nitrogen fixation activity of the root nodules, the growth of the vegetative mass of plants and the change in the activity of antioxidant enzymes (superoxide dismutase, ascorbate and guaiacol peroxidase) in different soybean organs for treatment of seeds by rhizobia incubated with lectin, in combination with fungicides have been studied. The objects of the study were symbiotic systems formed with the participation of soybean (Glycine max (L.) Merr.) Almaz and Bradyrhizobium japonicum (standard strain 634b) incubated with lectin. As disinfectants of soybean seeds, the following preparations with fungicidal activity were used – Maxim XL 035 PS, Fever, Standak Top according to one rate of active substance consumption of each preparation specified by the manufacturer. One part of the seeds treated with fungicides was inoculated with pure culture of suspension of rhizobia for one hour (titre of suspension concentration was 108 cells/ml). Another part of the seeds treated with fungicides was inoculated with rhizobia suspension, which was previously incubated with a solution of commercial lectin soybean at a concentration of 100 μg/ml. The research was conducted in strictly controlled conditions of a model vegetative experiment using microbiological, physiological, biochemical methods, gas chromatography, spectrophotometry. It was found that processing of soybean seeds with fungicides (Fever and Maxim XL) together with rhizobium inoculation contributed to the preservation of the nitrogen fixation activity of the root nodules and the growth of vegetative mass of plants. Under these conditions, the intensification of the activity of superoxide dismutase and ascorbate peroxidase was observed, as well as inhibition of the activity of guaiacol peroxidase in soybean root nodules in the phase of three true leaves and increased activity of all investigated enzymes in the phase of mass flowering. It has been established that the use of complex treatment of seeds by soybean rhizobia incubated with lectin and fungicides leads to an increase in the activity of superoxide dismutase and guaiacol peroxidase in root nodules in the phase of three true leaves and the growth of the activity of ascorbate peroxidase in the phase of mass flowering. At the same time, the inhibition of the growth of vegetative mass of plants and their symbiotic properties occurred, as evidenced by the decrease in the nitrogen fixation activity of the root nodules for the joint treatment of seeds with fungicides and lectin. A specific reaction of investigated enzymes in the roots and leaves of soybean was shown, which was more pronounced in the phase of three true leaves, indicating the development of a typical antioxidant reaction to a complex treatment, as a kind of stress that is leveled to the phase of mass flowering. The degree of reaction of antioxidant enzymes in the studied symbiotic systems Glycine max – Bradyrhizobium japonicum depends on the nature of the active substance fungicides and the manifestation of their joint effect in a complex with rhizobia incubated with lectin

    Математичне моделювання робочого процесу вібраційного гідроприводу плити пресування твердих побутових відходів

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    Наведена математична модель вібраційного гідроприводу пресування з використанням генератора імпульсів тиску диференціальної дії, яка дає змогу досліджувати динаміку вказаного гідроприводу для вибору більш раціонального способу пресування ТПВ. В результаті проведення математичного моделювання встановлено, що вібраційний спосіб пресування ТПВ збільшує їх коефіцієнт ущільнення на 24-26% порівняно із статичним способом, що дозволить суттєво підвищити продуктивність сміттєвозів в цілому (економія пального 2,2 т/рік на однин автомобіль) за рахунок кращої наповненості кузова

    Вітроенергетична установка із поворотними вітрилами

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    Запропонована конструкція вертикально-осьової вітроенергетичної установки із поворотними вітрилами, а також наведені розрахункові залежності для оцінювання і вибору основних конструктивних параметрів і силових характеристик установки при проектуванні.The design of vertical-axis wind power station with rotating sails, and also shows the calculated for the evaluation and selection of basic design parameters and strength characteristics of the unit in the design

    Epithelial dysregulation in obese severe asthmatics with gastro-oesophageal reflux

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    Developing of Multi-factor Authentication Method Based on Niederreiter-mceliece Modified Crypto-code System

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    Two-factor authentication methods to date, are considered by experts as authenticators resistance amplification mechanisms, while ensuring the authenticity services in various fields of high technology, financial and insurance sectors of the market, large banking institutions and public sector enterprises. Thus, authenticators based on OTP passwords and various types of tokens are typically used in the ABS. The suggested synergistic threat assessment approach revealed that attackers use a comprehensive approach to the implementation of threats, based on a combination of social engineering techniques with traditional methods, of disguise and infiltration. New types of cyber-attacks are also used to effectively embed malware on mobile communication devices, which in turn leads to a decrease in the profitability of the two-factor authentication methods based on SMS messages and OTP passwords in ABS. The proposed safety mechanisms based on modified crypto code Niederreiter and Mc-Eliece systems allow to ensure reliability (based on the use of elliptical error-correcting codes) and safety (proposed cryptosystem are secret models of provable resistance) of data transmitted. Their usage in the multi-factor authentication protocol ensures the security of the physical separation of transmission of the parts of authenticator of banking transactions through mobile lines (using the Niederreiter MCCS) and ABS (using the McEliece MCCS). The proposed mathematical model and algorithms of practical implementation of the Niederreiter MCCS allow, based on the error vector symbol shortening, to reduce the energy capacity of the group operations, reduce the power of the Galois field to GF 26–27, providing the required cryptographic resistance

    An optical 3D sound intensity and energy density probe

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    In this paper, an optical sensor capable of measuring pressure and the three orthogonal particle velocities at a point is presented. This sensor can be used to measure three-dimensional sound intensity or energy density in the presence of strong electro-magnetic and radio-frequency fields. The benefits of the sensor compared to traditional p-p intensity probes is discussed, as well as the design, construction and performance of the sensor. It will be seen that this new type of sensor has many advantages compared to traditional sensors.Cazzolato, B. S., Halim, D., Petersen, D., Kahana, Y. and Kots, A.http://www.mecheng.adelaide.edu.au/anvc/abstract.php?abstract=33
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