Galina V. Mirskaya

Due to the increased anthropogenic load, crops are polluted with heavy metals, including nickel (Ni). This is a serious environmental problem, as Ni penetrates barrier-free into cereal crops and accumulates in the grains used by humans and animals for food. Wheat is one of the main staple crops, cultivated in many countries. This study suggested that plant growth promoting bacteria (PGPB) with varying enzymatic activities could help wheat plants to cope with Ni stress by reducing Ni toxicity and regulating the metal’s homeostasis. PGPB Bacillus megaterium AFI1 has a strong phosphate-solubilizing activity and produces siderophores, while Paenibacillus nicotianae AFI2 has nitrogen-fixing and silicate-solubilizing activities. Both strains produce indole and polysaccharides and have 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. PGPB under Ni exposure (100 mg/kg of soil) significantly increased grain yield (by 34–42%) and decreased (by 20–33%) Ni content in wheat grains. PGPB also decreased malondialdehyde (MDA) and H₂O₂ levels in wheat plants under Ni stress. The contents of iron (Fe), boron (B), nitrogen (N) and phosphorus (P) decreased significantly and potassium (K) and zinc (Zn) oppositely increased significantly in all plant organs under Ni exposure. The inoculation with AFI1 mainly increased P and Fe, and the inoculation with AFI2 increased N and silica (Si) in wheat grains under Ni stress. In our experiments, under nickel exposure PGPB Bacillus megaterium AFI1 and Paenibacillus nicotianae AFI2 increased antioxidant protection of plants by decreasing the level of stress ethylene and regulating the homeostasis of nutrients in wheat plants. These PGPB can be considered as promising candidates for the development of biologicals to be used for growing plants in soils with low levels of nickel contamination.

Томат является одной из ведущих культур в современном тепличном производстве. Основная доля валовых сборов томата приходится на культивационные сооружения, оборудованные системами контроля климата, искусственного освещения и обеспечения растений элементами питания. Многомерная оптимизация условий световой, воздушной и корнеобитаемой среды с учетом биологических потребностей томата на разных этапах роста и развития является актуальной задачей, направленной на обеспечение стабильного формирования высокого урожая и качества растительной продукции. Цель работы: оценка зависимости продуктивности растений томата и качества его плодов от состава питательного раствора при различных уровнях облученности в регулируемых условиях интенсивной светокультуры. Исследование проводили на агробиополигоне ФГБНУ АФИ в условиях интенсивной светокультуры. Установлено, что выращивание томата при интенсивности светового потока 120 Вт м–2ФАР по сравнению с наблюдаемым при облученности 60 Вт м–2 ФАР способствовало уменьшению достоверно или в виде тенденции высоты растений (на 9–17%), увеличению площади, массы листьев и вегетативной надземной массы (на 2–16%), а также массы одного плода (на 40%), массы плодов с растения и урожая с м2 (на 109–140%) одного яруса вегетационной светоустановки (ВСУ) во всех исследуемых вариантах с различными концентрациями питательного раствора. Наиболее существенные значения указанных показателей установлены в вариантах с максимальным уровнем минерального питания в генеративную фазу развития растений при обоих условиях облученности. Фактор облученности растений оказывал существенно более значимое влияние на высоту, оцениваемые показатели продуктивности растений томата, качества его плодов, а фактор уровня минерального питания – на площадь, масс-метрические характеристики листьев вегетативной надземной части. Установлено более высокое содержания сухого вещества (на 14–20%) в плодах томата во всех вариантах концентрации питательного раствора при облученности 120 Вт м–2 ФАР. Содержание нитратов в плодах при более низкой облученности 60 Вт м–2ФАР превышало (на 43–54%) их количество в плодах, выращиваемых при 120 Вт м–2 ФАР, однако во всех исследуемых вариантах было значительно ниже предельно допустимых концентраций (ПДК). Полученные результаты свидетельствуют о важности предварительного подбора состава питательного раствора и режима питания растений томата на разных этапах развития в светокультуре. Tomatoes are a leading crop in modern greenhouse production. Most gross tomato yields are produced in greenhouses equipped with climate control systems, artificial lighting, and nutrient supply. Multidimensional optimization of light, air, and root conditions, considering the biological needs of tomatoes at different stages of growth and development, remains an unresolved and pressing issue aimed at ensuring stable development, high yields, and high-quality plant products. The objective of this study was to evaluate the response of tomato plants to light intensity at varying levels of mineral nutrition in a controlled agroecosystem, based on integral indicators of yield and fruit quality. The study was conducted at the agrobiological testing ground of the Agrophysical Research Institute under intensive light conditions. It was established that growing tomatoes at a luminous flux intensity of 120 W m–2 PAR contributed to a significant or trend decrease in plant height (by 9–17%), an increase in the area, leaf weight and vegetative above-ground mass (by 2–16%), as well as the weight of one fruit (by 40%), the weight of fruits per plant and the yield per m2 (by 109–140%) of one tier of the vegetation lighting system (VLS) in all the studied variants with different concentrations of the nutrient solution compared to those at an irradiance of 60 W m–2 PAR. The most significant values of the specified indicators were established in the variants with the maximum level of...

К числу возможных решений проблемы круглогодичного обеспечения населения свежей овощной продукцией отнесено создание и широкое применение наукоемких масштабируемых фитотехкомплексов на основе современных ресурсосберегающих технологий, включающих в себя приемы организации воздушной, световой и корнеобитаемой среды, а также набора адаптированных к условиям выращивания культур. Томат занимает одно из ведущих мест среди овощных культур защищенного грунта. Цель настоящей работы – изучить влияние корнеобитаемой среды на продуктивность, качество карликовых форм томата в регулируемых условиях интенсивной светокультуры и оценить их адаптационную способность при выращивании методом малообъемной гидропоники в поликарбонатной теплице. Исследования проведены в регулируемых условиях интенсивной светокультуры Агрофизического научно-исследовательского института (АФИ) и поликарбонатной теплице Федерального научного центра овощеводства (ФНЦО). Установлено, что выращивание томата методом панопоники на тонкослойном и малообъемном аналогах почв (ТАП и МАП соответственно) способствовало сокращению (на 10–30%) периода «всходы – созревание», а также значимому повышению урожайности (на 45–176%) исследуемых сортов. Выявлено отсутствие достоверных различий по показателям продуктивности растений и содержанию макро- и микроэлементов в плодах томата в обоих вариантах корнеобитаемой среды. Прослеживается значимое увеличение в плодах всех сортов сухого вещества (на 11–20%), каротина (на 5–11%), суммы сахаров (на 2–11%), витамина С (на 2–6%) при выращивании растений на ТАП. Содержание нитратов не превышало предельно допустимых концентраций (ПДК) во всех вариантах. Оценка адаптационной способности исследуемых сортов томата при выращивании их в поликарбонатной теплице ФНЦО методом малообъемной гидропоники показала отсутствие значимых различий в первом (зимне-весеннем) обороте и сокращение (на 6–22%) во втором (весенне-летнем) обороте периода «всходы – созревание»; увеличение значений урожайности на 11–153% в первом обороте, на 7–116% – во втором, по сравнению с их ключевыми сортовыми характеристиками. Наибольшая продуктивность среди рассмотренных сортов установлена в первом обороте, при этом у карликовых сортов Наташа, Тимоша, Маленький Мук высота растений и масса плода были больше во втором обороте, а у детерминантных (Огниво, Жегалов) – в первом. Сравнение полученных результатов роста и развития томатов в регулируемых условиях интенсивной светокультуры и поликарбонатной теплицы показало сокращение периода «всходы – созревание» на ТАП на 10–35 дней, МАП – на 1–27 дней, а также увеличение урожайности на ТАП на 6–38%, МАП – на 9–46% в интенсивной светокультуре, по сравнению с первым и вторым оборотами в поликарбонатной теплице. С учетом этого, согласно выводам авторов статьи, для выращивания в культивационных сооружениях различного типа, в том числе методом панопоники при искусственном освещении, могут быть рекомендованы все исследуемые сорта томата. The solution to the problem of year-round supply of fresh vegetable products to the population is the creation and widespread use of high-tech, scalable phytotechnological complexes based on modern resource-saving technologies, including methods for organizing an air, light and root habitat environment, as well as a set of crops adapted to the growing conditions. Tomato occupies one of the leading places among greenhouse vegetables. The purpose of the work was to study the effect of the root environment on the productivity and...

The aim of this research was to study the effect of plant-growth-promoting bacteria (PGPB) isolated from the drought-tolerant plants camel thorn (Alhagi pseudoalhagi (M.Bieb.) Fisch) and white pigweed (Chenopodium album L.) on wheat (Triticum aestivum L.) plants cv. Lenigradskaya 6, growing under hydroponic conditions and osmotic stress (generated by 12% polyethylene glycol-6000 (PEG)). Based on the assumption that plants create a unique microbiome that helps them overcome various stresses, we hypothesized that bacteria isolated from drought-tolerant plants may assist cultivated wheat plants in coping with drought stress. PGPB were isolated from seeds and leaves of plants and identified as Bacillus spp. (strains Cap 07D, Cap 09D, and App 11D); Paenibacillus sp. (Cap 286); and Arthrobacter sp. (Cap 03D). All bacteria produced different phytohormones such as indole acetic acid (IAA), abscisic acid (ABA), and gibberellic acid (GAS₃) and were capable of stimulating wheat growth under normal and osmotic stress conditions. All PGPB reduced the malondialdehyde (MDA) content, increased the total chlorophyll content by increasing chlorophyll a, and modulated wheat hormone homeostasis and CAT and POX activities under osmotic conditions. Selected strains can be promising candidates for the mitigating of the drought stress of wheat plants.

Ensuring the technical and technological possibility of regularly obtaining fresh, high-quality plant production in Antarctic stations is an urgent task of our time. This work is devoted to studying the growth and development of leaf vegetable crops and the main quality indicators of their edible parts when grown in the phytotechnical complex greenhouses at the “Vostok” Antarctic station and at the agrobiopolygon of the Agrophysical Research Institute (AFI). The plants, belonging to 13 varieties of 9 types of leaf vegetable crops (arugula, garden cress, cabbage, mustard, leaf radish, leaf lettuce, amaranth, dill, parsley leaf), were studied during five growing seasons at the “Vostok” station and at the AFI agrobiopolygon under controlled conditions (control). The experimental data obtained demonstrate the high productivity of the phytotechnical complex for most of the investigated crops per unit of useful area, with lower costs of electricity and water consumption per unit of production compared with a number of greenhouses at foreign Antarctic stations and greenhouse complexes with controlled conditions located on other continents. Lettuce crops were the most adapted to the growing conditions at the Antarctic station “Vostok”. They did not differ in their evaluated characteristics from the control. All other investigated crops, while not differing in their development rate and quality, had statistically significant (16–61%) decreases in their yield per 1 m² per year. This may demonstrate the difference in the “genotype–environment” interaction in plants grown at the Antarctic station and AFI agrobiopolygon, probably due to the different barometric pressure and partial pressure of oxygen at the two locations. The positive psychological effects of the greenhouses were identified along with nutritional and other qualities of the plants.

This work is devoted to the description of the synthesis of hydrogels in the process of cryotropic gel formation based on copolymerization of synthesized potassium 3-sulfopropyl methacrylate and 2-hydroxyethyl methacrylate (SPMA-co-HEMA) and assessing the potential possibility of their use as substrates for growing plants in intensive light culture in a greenhouse. Gel substrates based on the SPMA-co-HEMA were created in two compositions, differing from each other in the presence of macro- and microelements, and their effects were studied on the plants’ physiological state (content of chlorophylls a and b, activity of catalase and peroxidase enzymes, intensity of lipid peroxidation, elemental compositions) at the vegetative period of their development and on the plants’ growth, productivity and quality of plant production at the final stages of development. Experiments were carried out under controlled microclimate conditions. Modern and standard generally accepted methods of gels were employed (ATR-FTIR and ¹³C NMR spectral studies, scanning electron microscopy, measurement of specific surface area and pore volume), as well as the methods of the physiological and chemical analysis of plants. The study demonstrated the swelling ability of the created gel substrates. Hydrogels’ structure, their specific surface area, porosity, and pore volume were investigated. Using the example of representatives of leaf, fruit and root vegetable crops, the high biological activity of gel substrates was revealed throughout the vegetation period. Species specificity in the reaction of plants to the presence of gel substrates in the root-inhabited environment was revealed. Lettuce, tomato and cucumber plants were more responsive to the effect of the gel substrate, and radish plants were less responsive. At the same time, more pronounced positive changes in plant growth, quality and productivity were observed in cucumber and lettuce in the variant of gel substrates with macro- and microelements and in tomato plants in both variants of gel substrates. Further research into the mechanisms of the influence of gel substrates on plants, as well as the synthesis of new gel substrates with more pronounced properties to sorb and retain moisture is promising.

Elaborating on the methods and means of enriching nutrition, including that of plants, with a number of microelements that are vital for humans is now very important due to the unresolved acute problems of micronutrient deficiency and imbalance, which affect the majority of the population of various countries in the world. Promising solutions for the implementation of biofortification in terms of safety, efficiency, size, biocompatibility, and transportability are the water-soluble derivatives of C₆₀ or C₇₀ fullerene. By now, the use of water-soluble fullerenes (C₆₀(OH)_22–24 or C₇₀(OH)_12–14 fullerenols, C₆₀ fullerene with glycine or with arginine: C₆₀-L-Gly or C₆₀-L-Arg) with various functional groups for plant enrichment is pioneering. Experimental research work was carried out at the agrobiopolygon of the Agrophysical Research Institute under controlled microclimate conditions. This work constituted an assessment of the influence of C₆₀(OH)_22–24 fullerenol introduction into the soil on the content of macro- and microelements in the soil and in plants, for example, cucumber, as well as on the plants’ physiological state (photosynthetic pigments, the intensity of lipid peroxidation, the activity of peroxidase and catalase enzymes), growth, and element content. Its aim was to study the possibility of enriching the plants’ production (Chinese cabbage, tomato, and cucumber) with compositions of the fullerene derivatives (C₆₀-L-Gly or C₆₀-L-Arg, C₆₀(OH)_22–24 or C₇₀(OH)_12–14 fullerenols) and selenium or zinc compounds by introducing them into a nutrient solution or by foliar treatment of plants. It was revealed that the introduction of solutions of C₆₀ fullerenol in various concentrations (1 mg/kg, 10 mg/kg, and 100 mg/kg) into soddy-podzolic sandy loamy soil contributed to the activation of the processes of nitrogen transformation in the soil, in particular, the enhancement of the process of nitrification, and to the increase in the content of mobile forms of some macro- and microelements in the soil as well as of the latter in plant organs, for example, in cucumber plants, especially in their leaves. Along with this, the plants showed an increase in the content of photosynthetic pigments, a predominant decrease in the activity of the oxidative enzyme peroxidase and in the intensity of lipid peroxidation, and an increase in the content of the reducing enzyme catalase. The improvement in the physiological state of plants had a positive effect on the growth rates of cucumber plants. The compositions of solutions of amino acid fullerenes (C₆₀-L-Gly or C₆₀-L-Arg) and sodium selenate as well as C₆₀ or C₇₀ fullerenols and zinc sulfate, selected on the basis of different charges of molecules or functional groups of fullerene derivatives, showed higher efficiency at low concentrations in enriching the plant products of Chinese cabbage, tomato, and cucumber with selenium and zinc, respectively, compared with mineral salts of the indicated elements and control (edible part of Chinese cabbage: by 31.0−89.0% relative to that in the control and by 26.0–81.0% relative to the treatment of plants with a sodium selenate; tomato fruits: by 33.7–42.2% relative to that in the control and by 10.2–17.2% relative to the treatment of plants with a sodium selenate; cucumber fruits: by 42.0–59.0% relative to that in the control and by 10.0–23.0% relative to the treatment of plants with a zinc sulfate). At the same time, the quantitative characteristics of growth, productivity, and/or quality of the obtained products increase and improve accordingly. The prospects for further research include an in-depth study into the mechanisms of the compositions of fullerene derivatives and various compounds of trace elements’ influence on the plants, as well as the synthesis and study of the various exo- and endo derivatives of fullerenes’ properties, including C₆₀ complex compounds with transition metals and fullerenes, which, inside their carbon networks, contain atoms of various chemical elements, such as lanthanum and others.

The effect of a plant growth-promoting bacterium (PGPB) Bacillus sp. V2026, a producer of indolyl-3-acetic acid (IAA) and gibberellic acid (GA), on the ontogenesis and productivity of four genotypes of early-maturing spring wheat was studied under controlled conditions. The inoculation of wheat plants with Bacillus sp. V2026 increased the levels of endogenous IAA and GA in wheat of all genotypes and the level of trans-Zeatin in Sonora 64 and Leningradskaya rannyaya cvs but decreased it in AFI177 and AFI91 ultra-early lines. Interactions between the factors “genotype” and “inoculation” were significant for IAA, GA, and trans-Zeatin concentrations in wheat shoots and roots. The inoculation increased the levels of chlorophylls and carotenoids and reduced lipid peroxidation in leaves of all genotypes. The inoculation resulted in a significant increase in grain yield (by 33–62%), a reduction in the time for passing the stages of ontogenesis (by 2–3 days), and an increase in the content of macro- and microelements and protein in the grain. Early-maturing wheat genotypes showed a different response to inoculation with the bacterium Bacillus sp. V2026. Cv. Leningradskaya rannyaya was most responsive to inoculation with Bacillus sp. V2026.

The present study demonstrates the Ni toxicity-ameliorating and growth-promoting abilities of two different bacterial isolates when applied to wheat (Triticum aestivum L.) as the host plant. Two bacterial strains tolerant to Ni stress were isolated from wheat seeds and selected based on their ability to improve the germination of wheat plants; they were identified as Bacillus megaterium AFI1 and Paenibacillus nicotianae AFI2. The protective effects of these epiphytic bacteria against Ni stress were studied in model experiments with two wheat cultivars: Ni stress-tolerant Leningradskaya 6 and susceptible Chinese spring. When these isolates were used as the inoculants applied to Ni-treated wheat plants, the growth parameters and the levels of photosynthetic pigments of the two wheat cultivars both under normal and Ni-stress conditions were increased, though B. megaterium AFI1 had a more pronounced ameliorative effect on the Ni contents in plant tissues due to its synthesis of siderophores. Over the 10 days of Ni exposure, the plant growth promotion bacteria (PGPB) significantly reduced the lipid peroxidation (LPO), ascorbate peroxidase (APX), superoxide dismutase (SOD) activities and proline content in the leaves of both wheat cultivars. The PGPB also increased peroxidase (POX) activity and the levels of chlorophyll a, chlorophyll b, and carotenoids in the wheat leaves. It was concluded that B. megaterium AFI1 is an ideal candidate for bioremediation and wheat growth promotion against Ni-induced oxidative stress, as it increases photosynthetic pigment contents, induces the antioxidant defense system, and lowers Ni metal uptake.

Introduction. The development of ideas about the influence of the light environment - the radiation spectrum, intensity and duration of exposure, on the physiology of plants, serves as the basis for the creation of effective light sources for protected ground.Purpose. Comparative test of the influence of a light environment with different spectral composition on the productivity and quality of tomatoes in conditions of intensive photo culture.Methods. Investigations were made under controlled conditions of intensive photoculture when growing dwarf tomatoes of the variety Natasha selections of the “Federal Scientific Vegetable Center” on thin-layer soil analogs with the supply of a nutrient solution to the plant roots through a slit capillary in vegetative light installations developed at the ARI. The light sources were high-pressure sodium lamps and LED lamps SD1, SD2, and SD3 with different emission spectra. Results. Tomatoes of the Natasha variety, illuminated during development with HPS lamps, formed almost the same yield with an average fruit weight of 42.5 kg/m2 per layer per year. Natasha tomato grown under LED lamps showed a tendency to lower productivity by 29% under SD1 and by 8% under SD2 and higher by 19% under underSD3 compared to that under HPS lamps. A comparative assessment of the biochemical composition of tomato fruits indicates their high quality under all tested light sources.Conclusion. Cultivation of dwarf tomato varieties on thin-layer soil analogs showed the best results in terms of productivity with good quality plant products under LED lamps SD3 with a radiation spectrum close to sunlight.