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During the pot experiment in soil-sandy culture, the effect of foliar treatment with 0.005 % aqueous solutions of 1-naphthylacetic acid (1-NАА), gibberellic acid (GA3) and 6-benzylaminopurine (6-BAP) on growth and physiological and biochemical characteristics of sweet pepper cv. Antey were investigated. It was found that exogenous growth stimulators at the budding stage led to an increase in the plants linear size, leaves number, the leaves, stems and roots fresh weight, as well as the whole plant dry weight. After treatment with growth regulators, the area of leaf blades increased throughout the growing season, and at the stage of fruit formation — the total leaf area of the whole plant. Exogenous 6-BAP significantly increased the amount of chlorophyll in the leaves, while under the action of GA3 this index decreased. Growth stimulants thickened the leaf blades due to the proliferation of chlorenchyma cells, namely the increase in the volume of columnar parenchyma cells. 1-NАА and 6-BAP also increased the size of the spongy parenchyma cells. All growth regulators reduced the content of IАА and ABA in the stems. 1-NАА and GA3 increased the content of endogenous GA3 in the stems, and 6-BAP decreased it. The growth regulators increased the content of endogenous IАА in the leaves, the maximum increase occurred during treatment with synthetic auxin. 1-NАА and 6-BAP decreased the content of endogenous GA3, and under the action of exogenous GA3 there was an increase in this phytohormone. All growth substances reduced the ABA content in the leaves. The most significant decrease was observed under the action of exogenous GA3. Growth substances have been shown to reduce the amount of cytokinins in stems and increase in leaves. 1-NАА minimized the cytokinins content in the stems and maximized in leaves. Treatment with a solution of GA3 had no significant effect on the cytokinins accumulation. All growth regulators increased the yield of sweet pepper culture by increasing the number of fruits per plant and the average weight of one fruit. The most effective was the use of a synthetic analogue of cytokinins — 6-BAP.

The effect of a complex growth regulator stimpo, both separately and together with fungicides fever and standak top on the formation and functioning of the symbiotic apparatus soybean—Bradyrhizobium japonicum were investigated. It was estimated the possibility of its use as a mitigator of the negative effects of fungicides on the studied soybean-rhizobia symbiotic systems. It was revealed that the use of fungicides standak top, fever and complex growth regulator stimpo, both individually and in combination, does not cause significant changes in the activity of growth processes of soybean plants, and their effects depended on the specifics of these preparations and the stage of plant development. It was found that the fungicides used by us cause a slight inhibition of the nodulating activity of rhizobia at the stage of two true leaves. At the same time, in the stage of three true leaves and budding, these fungicides promote the nodule formation and nitrogen-fixing activity. The stimulating effect of the stimpo on the studied symbiotic systems was confirmed. It was shown that the treatment of seeds with this growth regulator leads to a significant increase in the number and weight of root nodules and their nitrogen-fixing activity. In this case, the effect of the use of stimpo in combination with fungicides depends on the active substances, the spectrum of fungicides action and the stage of plant development. It was revealed the prospects of using the complex growth regulator stimpo in pre-sowing inoculation of legume seeds in order to improve the functioning of legume-rhizobial symbiosis. However, its use at a concentration of 25 ml/t of seeds did not absolve the toxic effects of the studied fungicides on the soybean symbiotic systems.

The effect of high temperature stress on the cytokinins content in the overground part and roots of winter rye (Secale cereale L.) plants of the Boguslavka variety was studied under conditions of pot experiment. Plants were grown from seeds for 7 days at an air temperature of +16 °С, stress was created by transferring them to a thermostat with a temperature of +35 °С for 2 h (alarm stage) or twice for 6 h for two days (acclimation stage). Plants were also analyzed 5 days after the end of stressor action (recovery stage). The cytokinins qualitative composition and quantitative content were investigated by high performance liquid chromatography on Agilent 1200 LC liquid chromatograph with diode-matrix detector G 1315 B (USA). Significant changes in morphometric parameters, which reflected the inhibition of growth processes in rye plants under heat stress, were detected after two days of the experiment, while the pool of endogenous cytokinins considerable changed after 2 h of hyperthermia. In particular, concentration of trans-zeatin and trans-zeatin riboside notably decreased in the overground part, and in the roots — increased. The accumulation of free cytokinins was observed in the overground part of rye seedlings after two days of exposure to heat stress, at the same time a decrease in their levels was recorded in the roots. After a 5-day recovery period, the experimental plants differed from the control by a higher content of trans-zeatin and trans-zeatin riboside (approximately by 20 %) both in the overground part and in the roots. In general, studies have shown that hyperthermia has a differentiated effect on the content of individual cytokinins and their localization in the overground and underground parts of winter rye seedlings of Boguslavka variety. The detected fluctuations of cytokinins indicate their direct participation in the regulation of winter rye plants adaptation to the hyperthermia action.

Results on the studies of kernels and their structural parts: endosperm, pericarp and the germ of the maize hybrid ZP 633 that is very desirable for human consumption are presented. For the first time, the method of infrared spectroscopy was apply to record and study all spectral bands (of very high, high, low and very low intensity) of the infrared spectrum of maize hybrid kernels, endosperm, pericarp and the germ. Based on performed studies it can be stated that infrared spectra of maize hybrid kernels, endosperm, pericarp and the germ are characterised by all their spectral bands and several parameters: number, intensity, kinetics and the distribution of the site of origin in the wavenumber range of 400—4000 cm–1. These parameters were particularly observed for both kernels and their parts (endosperm, pericap and the germ). Spectral bands of very high and high intensity are also characterised by the stated parameters: the number that usually ranges from 3 to 5, intensity, various kinetic forms, as well as the distribution of their origin within the wavenumber range. These spectral bands make possible the identification of organic compounds, their fragments and molecular structures that determine them. In case of spectral bands for the kernel, endosperm, pericarp and the germ with very high and high intensity, organic compounds can be identified as: proteins, lipids, sugars, esters, amides, ketones, aldehydes, carboxylic acids, ethers, phenols, alcohols, aromatic carbohydrates, acyclic compounds, alkenes, alkanes, and alkynes. Spectral bands of the kernel, endosperm, pericarp and the germ of low and very low intensity are also characterised by the stated parameters: the number that can differ, low intensity, the distribution of sites of their origin, and especially the frequency of vibrations of valence bonds of functional groups of organic molecules. Spectral bands of the kernel, endosperm, pericarp and the germ of low and very low intensity, also provide the possibility to identify the excited state of molecular structures and valence bonds of functional groups of organic compounds. The excited state of molecular structures and valence bonds of functional groups of organic compounds is expressee in different forms of vibration movements: symmetric and asymmetric valence vibration (stretching), deformation vibration of valence bonds and molecular structures (scissoring), rocking of valence bonds and molecular structures (rocking), wagging of valence bonds and molecular structures (wagging), twisting of valence bonds and molecular structures (twisting), trembling of valence bonds and molecular structures (trembling).

The problems and main achievements of researches of mechanisms of action of physiologically active substances, including herbicides are analyzed. Considerable attention is paid to the results of fundamental researches aimed at studying the theoretical bases of plant growth and development management, and applied developments to create growth regulators of natural origin, and the use of synthetic and natural physiologically active substances in agriculture. The main achievements of researches on the physiology of herbicides action: elucidation of specific sites of herbicide action, determination of mechanisms of uptake, translocation and detoxification of active substances of herbicides in plants, establishment of basic patterns of interaction effects in herbicide complexes are described. Innovative developments are discussed: environmentally friendly weed control technologies, creation of herbicide compositions to prevent the emergence of resistance. It is concluded that the discovery of the mechanisms of herbicide-induced pathogenesis will open opportunities for the search for new highly effective herbicides, solving the problem of resistance and further improving the chemical method of weed control.

The question of expediency and efficiency of application of microbial preparations in technologies of cultivation of agricultural crops made on the basis of active strains of nodule bacteria was observed and their role in providing plants with biologically fixed nitrogen was characterized. Information on the prevalence, benefits and prospects of using the chemical method of plant protection against pathogens, phytophagous and weeds in agrophytocenoses was presented. Peculiarities of pesticide evaluation according to a number of ecotoxicological indices are highlighted. Data on the effects of individual active substances and mixed chemicals on the viability and reproduction of nitrogen-fixing microorganisms in pure culture were presented. It was shown that severity of these effects depends on the purpose, mechanisms of action, the nomenclature of artificially synthesized substances in the composition of preparations, the concentration applied, and genotype of rhizobia strains. It was noted that the adaptive reactions of microorganisms to the action of pesticides are manifested in the correction of biochemical and physiological processes, which ensure their continued existence under conditions of anthropogenic stress. The effect of chemical plant protection preparations under different methods of their application on symbiotic systems formed with the participation of active strains of nodule bacteria and legumes was analyzed. Depending on the genotypes of micro- and macrosymbionts, components of chemicals, a number of biotic and abiotic environmental factors, different effects of pesticides on the number and weight of root nodules, the N2 assimilation rate, grain yield and quality indices were noted. Possible ways of combining the processes of legume seeds bacterization and their treatment by preparations with fungicidal or insecticidal action due to the use of pesticide-tolerant strains of rhizobia and the involvement of additional components of protective action in the preparations were identified.

Based on original genetic variability, in terms of its effects on grain protein, starch and bioactive grain compounds biosynthesis, several new approaches in breeding of winter wheat, winter wheat-spelt, winter/spring hull-less barley and winter triticale were initiated. The final purpose of our initiatives is to introduce on the Ukrainian grain market an array of new varieties of the cereal crops mentioned above with biochemical, technological and nutritional grain characteristics required for development of new food products with functional food status as well as new grain technology end-use. Available in our breeding programs genetic variability, specially developed or transferred to cultivated wheat genome from wild species (gout grass Aegilops tauschii (2n = 2x = 14), Ae. cylindrica (2n = 4x = 28), wild emmer Triticum dicoccoides (2n = 4x = 28) allows us to develop the new bread and biscuit wheat cultivars of the highest quality on red or white grain base. Newly introduced to our breeding programs the original genetic resources makes possible purposefully as well as in the large scale manipulate by wheat grain texture, nutritional and technological starch properties, grain hardness, technological and milling grain characteristics, that is entirely new for Ukrainian breeding, and that allows to enhance substantially the technological and nutritional wheat potential. We were first who initiated development in Ukraine new varieties of winter bread wheat and spelt-wheat, food end-use hull-less barley all possessing with colored (purple, black and blue) grain that allows substantially ameliorate nutritional and functional grain status as well as grain-derived food products of those crops. On the base of colored grain as well as on the wide grain hardness of wheat and food end-use hull-less barley grain we initiated the new for Ukrainian breeding developments – special end-use varieties for grouts and flakes. We also focus on the popularization in Ukraine of the whole-grain food derived from colored cereal grain as an important nutritional factor of health benefits. We initiated new breeding programs of the food end-use hull-less barley (winter, spring, alternative) varieties with elevated grain protein and soluble dietary fiber (beta-glucan), high amylose, low phytate, high anthocyanin and phytomelanin content, high grain antioxidant activity, unique nutrition black grained hull-less barley with ultra-low gluten content. Based on our own research as well as on the widely published foreign developments we make conclusion that the cereal functional food program should become as a state supported strategic program aimed on the health promotion of the Ukrainian nation

Photosynthesis is the basis of the production process of plants, thus the study of the structure of the photosynthetic apparatus and the mechanisms of its functioning and regulation are important for unveiling ways to increase crop productivity. The paper summarizes the results of research by scientists of the Institute of Plant Physiology and Genetics (IPPG) of the National Academy of Sciences of Ukraine in the global context of studying the role of photosynthesis in the production process and the formation of crop yields. The importance of the early period of research in the formation of methodological bases for studying the plant photosynthesis at laboratory and field conditions as well as taking into account its interaction with growth and development, mineral nutrition, etc. is emphasized; this laid the foundations of the national scientific school of physiology, biochemistry and ecology of photosynthesis. The results of main research and innovative developments, awarded by the State Prizes of USSR and Ukrainian SSR, as well as the Prizes M.G. Kholodny of NAS of Ukraine are presented. Scientists of IPPG NAS of Ukraine comprehensively characterized the structural and functional features of the photosynthetic apparatus at the levels of organization from subcellular to coenotic, and mechanisms of regulation in the sink-source system of plants in modern winter wheat varieties, and identified traits that can serve as physiological markers of productivity and drought-tolerance. It is established that high productivity of modern winter wheat varieties is related to prolonged duration of leaves assimilation apparatus during reproductive vegetation, increased photosynthesis activity and efficiency of solar radiation use at leaf and canopy levels, as well as improved stem depositing ability for water soluble carbohydrates. Based on the obtained results, the concept of autoregulation of photosynthesis and the strategy of assimilate distribution in the sink-source system of plants as factors of optimizing the functioning of the photosynthetic apparatus and increasing yield are formulated and developed. The results of research conducted in IPPG show that further genetic improvement of new varieties of winter wheat can come about through the increase in activity of the photosynthetic apparatus at the leaf and canopy levels in the close connection with optimizing growth and ontogenetic dynamics of biomass distribution in whole plant

The results obtained during 60 years of the investigations concerning biological nitrogen fixation made by the scientists of the Department of symbiotic nitrogen fixation are presented. It was considered the study of physiological and biochemical characteristics as well as regulation of the synthesis and functioning nitrogenase from lupine and soybean symbiotic systems. It was shown the contribution of the scientists of the department to the study of interaction between nitrogen fixation and photosynthesis and respiration in the symbiotic systems under different conditions during their formation and functioning. Special attention is paid to the study on interaction between symbionts during the formation of symbiotic and associative nitrogen fixing systems and importance of rhizosphere microbiome for plant development. Much attention is paid to disclosure of the role of lectins and carbohydrates in the formation of plant-bacterial systems and its functioning. The questions of the effect of environment factors (mineral nitrogen nutrition, water supply, plant growth regulators, fungicides) on symbiotic systems as well as of the role of phytohormones and antioxidant enzymes during their functioning, and of the development of means to increase symbiosis effectivity, in particular under stress are discussed. It was shown theoretical and practical importance the investigations made by the scientists of the department: creation of new high-productive soybean cultivars, obtaining new strains of nitrogen fixing bacteria (particularly, those which are the main part of bacterial fertilizers for strategical agricultural plants), development of new microbial fertilizers generation, setting up their semi industrial production, development and implementation the environmentally friendly technology for obtaining plant protein, creation and maintenance the collection of the strains of symbiotic and associative microorganisms which is a national heritage. The prospects of fundamental studies and practical developments concerning biological nitrogen fixation are discussed.

The anniversary article presents the current state, principles and methods of genetic improvement of plants and the main achievements of scientists of the Institute of Plant Physiology and Genetics of the National Academy of Sciences of Ukraine in this direction. A retrospective review is made of the discoveries of scientists awarded the Lenin Prize, the State Prizes of the USSR and Ukraine in the field of science and technology, and high government awards. Scientific data on the genetic threat caused by the Chernobyl accident and man-made pollution are summarized. Practical achievements in the field of heterosis and mutation selection of cereals, molecular markers use, genetic engineering, and remote hybridization are covered in detail. The results of the study and implementation in the programs of selection and genetic research of new genes and genetic systems that affect the quantitative and qualitative characteristics of grain are presented. Attention is paid to the innovative developments of the Institute, in particular to new high-yielding winter wheat varieties and hybrids of maize, which are widely sown in Ukraine and abroad, and their transfer to agricultural production.

An overview of the studies, which have been conducted and now are carrying out by the scientists of the Institute of Plant Physiology and Genetics of NAS of Ukraine, among whom there are many world famous researchers is presented in the article dedicated to the 75th anniversary of the Institute. There were considered the directions of investigations which were carried out at the Departments of the Institute as well as disclosed main achievements in solving problems arising in Biology, Agriculture and Economics. Significant contribution of the Institute to growing prestige of the agricultural sector of Ukraine was noted. Thus, it was underlined that scientific work of the scientists of the Institute organically combined fundamental researches and current applied problems of national importance. It was noted that the Institute have two scientific objects of national importance: «Collection of valuable samples of winter wheat and maize — cultivars, populations, unique mutants and recombinant lines, inbred lines of the Institute of Plant Physiology and Genetics of NAS of Ukraine», «Collection of the strains of symbiotic and associative nitrogen fixing microorganisms of the Institute of Plant Physiology and Genetics of NAS of Ukraine». The Institute publish scientific-theoretical journal and is the co-founder of other scientific-theoretical journal as well as coordinate the work of Ukrainian Society of Plant Physiologists and is the co-organizer of the conference of the Society. The Specialized academic council prepares both candidates and doctors of science in two specialties: plant physiology and genetics. Well-known scientific schools, that have been established and now are successfuly functioning at the Institute was outlined. It was presented numerous awards and rewards of the Institute and scientists, which testified to the importance of their achievements and high appreciation by our State and the international scientific community.

Assimilation apparatus of different leaves tyers in winter wheat varieties under adverse environmental conditions

In field experiments under adverse weather conditions (low air temperature and excess precipitation during the period of reproductive organs formation, and increased temperature and lack of precipitation during grain filling) the variability of the specific leaf weight (SLW) of different tiers, chlorophyll content and dry weight in 6 varieties of winter wheat at reproductive period of development was investigated. The erectoid orientation of upper leaves in all studied winter wheat varieties, regardless of the year of breeding was found. The best adaptation of the pigment apparatus to the unfavorable conditions, during the spring-summer vegetation, was observed in the Kyivska 17 variety. The high-productive winter wheat varieties Kyivska 17, Horodnytsia, Pochaina and Poradnytsia had higher flag leaf SLW than low-productive varieties Krasnopilka and Smuhlianka both at anthesis (respectively 5.16—5.79 and 4.77—4.95 mg/cm2) and at milk ripeness (respectively 5.12—5.70 and 4.47—4.86 mg/cm2). A positive relationship between the main shoot ear grain productivity, the number of grains from the ear, and 1000 grains weight with certain traits of flag leaf assimilation apparatus at anthesis and milk ripeness was shown. It was found that the physiological marker of high main shoot ear grain productivity could be the flag leaf specific weight at anthesis and milk ripeness.

Effect of tebuconazole on the use of reserve substances deposited in the seed of Vicia faba L. at the heterotrophic phase of development under conditions of photo- and scotomorphogenesis

The combination of external (light/dark) factor and the action of the gibberellin synthesis inhibitor tebuconazole during seed germination significantly changed the pattern of source-sink relationships in horse beans seedlings. Under the action of the tebuconazole the epicotyl, root, and seedling length in general were reduced significantly, both at light and dark. Similarly, the dry matter mass of the seedling organs was decreased. Seed reserve substances were used more intensively under conditions of scotomorphogenesis, as evidenced by the minimum cotyledons dry matter mass in this variant and higher utilization rates of reserve substances for root and epicotyl formation during germination. The retardant application led to a slowdown in the outflow of seed reserves for the formation of epicotyl and root. Under conditions of scotomorphogenesis, the rate of reserve seed starch use was higher. The gibberellin biosynthesis inhibitor tebuconazole did not affect the rate of cotyledon starch hydrolysis, indicating an internal sufficient supply by reserved forms of gibberellins. The higher sugar content in the cotyledons of scotomorphic plants, both in the control and under the action of tebuconazole, is explained by the slowing of the outflow for the needs of organogenesis — the formation of root and epicotyl structures. Quantitative changes of the nitrogen content in the cotyledons of scotomorphic and photormorphic plants during germination were much smaller than the changes of the starch content. It was no significant effect of tebuconazole on the remobilization of nitrogen-containing compounds and mineral nutrients — phosphorus and potassium deposited in the seed, on the needs of organogenesis.

#vicia faba

Dynamics of photosynthetic pigments content in leaves of Vaccinium corymbosum L. during vegetation

[Open Access] [en] https://doi.org/10.15407/frg2021.01.055 #Vacciniumcorymbosum #chlorophyll #carotenoids #ontogenesis #Vaccinium The quantitative indices of plastid photosynthetic pigments in the leaves of deciduous shrubbery Vaccinium corymbosum L., which grow in the same climatic conditions in the south of Belarus, were studied in order to quantify and compare seasonal changes in the efficiency of photosynthesis. For each variety of the studied plants V. corymbosum L., certain differences were noted on the content of photosynthetic pigments in regard to the ontogenetic stage, in particular to the natural light period, which manifested in the relative content of chlorophylls a and b, the ratio between them, the relative content of carotenoids to chlorophylls. The data obtained on the absolute and relative plastid pigments content, as well as on the ratio between them, indicate the presence of varietal specificity in the plant reaction on reducing the length of daylight hours. Keywords: Vaccinium corymbosum, chlorophyll, carotenoids, ontogenesis, Vaccinium

The use of fungicides in integrated soybeans protection systems and their impact on the physiological and biochemical processes in plants under inoculation

https://doi.org/10.15407/frg2021.01.003

The review of literature data is given on the effect of various chemicals with fungicidal properties on the course of physiological and biochemical processes in soybean plants under conditions of seeds inoculation with nodule bacteria. The importance of soybean in integrated agricultural systems, and destabilizing factors for maximum realization of its genetic potential are shown. The influence of fungicidal preparations and their individual components on nodule bacteria in pure culture, legume-rhizobial symbiosis, photosynthetic apparatus, and features of the plant organism response at the level of redox reactions are considered. It is noted that the toxic effect of fungicides on nodule bacteria depends on the bacterial strain, the active substance and additional components of the pesticide, its concentration, storage temperature, the duration of interaction with bacteria. Certain mechanisms of fungicides negative influence on legume-rhizobial symbiosis are outlined, which consist in inhibition of phytoestrogen production by plants, decrease in synthesis of phytohormones and siderophores, violation of regulatory signaling system between macro- and microsymbionts, blocking the activity of nodulation genes and reducing the level of rhizobial Nod-factor. It is assumed that the multidirectional action of pesticides on the photosynthetic apparatus depends on the method of treatment, concentration and the active substances of fungicides. It is noted that changes in the antioxidant enzymes activity in soybean plants indicate the development of stress-protective reactions to chemical treatment. Possible ways to reduce the toxic effects of fungicides that will help maintain the efficiency of legume-rhizobial symbiosis with the combined use of biological preparations and chemical pesticides in soybean cultivation are shown.

[Open Access] [uk]

Induced mutagenesis in wheat: from ionizing radiation to site-specific gene editing https://www.frg.org.ua/en/2021/_29-54N1V53.htm #Triticumaestivum #wheat #inducedmutagenesis #genomeediting #CRISPRCas9 #Triticum Wheat (Triticum aestivum L.) occupies the largest cultivated area among crops, supplying a substantial part of energy, nutrients, fiber and protein to human. Whereas the wheat yield has been significant enhanced during the Green Revolution, the food needs also increases with the growth of human population. The breeding of highly productive cultivars with improved agronomic and nutrient characteristics remains an important challenge. Since the beginning of 20th century, induced mutagenesis using ionizing radiation and various chemicals has been practiced to increase the diversity of plant material in breeding. The method represents an effective tool for inducing a wide range of genetic changes. However, the vast majority of the generated random mutations, are rather deleterious and have to be cleaned up via cumbersome and time-consuming back-crossing procedures. Instead, site-specific endonucleases offer an opportunity of accurate and efficient target-specific modifications in the chosen loci selected by a researcher. The review provides a historic perspective on the induced mutagenesis technologies and the recent progress in genome editing based on customizable endonucleases. The main focus is on the advances of CRISPR/Cas technology, which emerged as the most widely used mean for crop genomes editing, including wheat with its complex hexaploid genome. The areas of application of the CRISPR/Cas systems for wheat improvement are described in detail. Particular attention is paid to the development of new approaches, based on genome editing systems for speeding up the production of wheat hybrids, improving wheat productivity and nutritional values. The legal regulations applied to the production and applications of the organisms obtained by targeted mutagenesis are also discussed. Keywords: Triticum aestivum, wheat, induced mutagenesis, genome editing, CRISPR/Cas9, Triticum

Influence of nutritional elements and fungicides on chlorophyll content in leaves of highly productive winter wheat varieties

[Open Access] [uk] The influence of nutrients and fungicides on the chlorophyll content in the leaves of winter wheat of high-yielding varieties Smuglyanka and Podolyanka was studied. There was a tendency to increase the chlorophyll content in the flag leaves of winter wheat and a statistically significant increase in its content in the leaves of the 2nd and 3rd levels under the application of compositions of triazole derivatives, strobilurin and microelements with magnesium and amino acids. Peculiarities of strengthening the chlorophyll accumulation in the leaves of different levels and the influence on the formation of crop productivity are considered.Keywords: Triticum aestivum L., inorganic elements, fungicides, Fusarium, chlorophyll, SPAD-index

#Triticum #Triticum aestivum #inorganic elements #fungicides #Fusarium #chlorophyll #SPAD-index

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