There was researched the effect of Bacillus subtilis bacteria in combination with salicylic (SA) and jasmonic (JA) acids on the state of the pro / antioxidant system (hydrogen peroxide content, catalase, peroxidase, superoxide dismutase activity) in connection with the development of potato resistance to late blight pathogen - oomycete Phytophthora infestans (Mont.) de Bary under moisture deficit conditions. Plants grown from microtubers of the Rannyaya Rosa cultivar were sprayed with a suspension of B. subtilis (108 cells / ml) and a mixture of bacteria with SA (10-6 M), JA (10-7 M), SA + JA (1:1). 3 days after treatment, the plants were infected with P. infestans (105 spores / ml) and cultivated under artificial soil drought conditions by reducing irrigation. When soil moisture reached 40±5% (7 days after infection), biochemical parameters were assessed in plants. A decrease in the degree of leaves damage by P. infestans was revealed when treated with B. subtilis in combination with SA and JA. The mechanism of increasing the resistance of potato plants to late blight when treated with Bacillus subtilis bacteria in combination with signaling molecules under conditions of drought was associated with the accumulation of H2O2 and modulation of antioxidant enzymes activity.
The study of the composition of biologically active substances, alcoholic extracts from flowers of Aeculus hippocastanum L. According to the results of HPLC-MS and GC-MS analyzes, the extract contains the main amounts of phenolic compounds: quercetin, epicatechin, kaempferol. In addition, the extract contains fatty acids and their esters, alcohols, 3-deoxy-d-manno lactone, 1,2,3,5-cyclohexantethrol, α-methyl-mannofuranoside, γ sitosterol. Antioxidant activity of an extract from flowers of A. hippocastanum is associated with the peculiarities of the compositionof biologically active substances. The toxological-hygienic assessment of flowers of this species in acute and subacute experiments showed that it belongs to the 4th hazard class (low hazard).
In the modern conditions of agricultural development, the use of microbiological preparations as an alternative to mineral fertilizers and chemical plant protection products is gaining wide interest and practical significance. Soil microorganisms have the ability to interact with the root system of plants, optimize mineral nutrition, synthesize growth hormones and antimicrobial compounds that inhibit the development of phytopathogenic fungi and bacteria and have a stimulating effect on the growth and development of cultivated crops, increasing their resistance to phytopathogens and stress. The search for environmentally friendly technologies, the use of enzymes and active metabolites of bacterial origin, or the use of bacterial strains that promote plant growth is a promising direction. The effect of culture fluid of Bacillus ginsengihumi and Pantoea brenneri on the average length of the plant stem was studied. When processing wheat seeds of P. brenner AS3, the length of the first leaf increased by 50%, and B. ginsengihumi M2.11 by 25%.
From the data on the structural heterogeneity of indicator plants (Berteroa incana (L.) DC., Plantago major L., Reseda lutea L., Echium vulgare L., and Capsella bursa-pastoris (L.) Medik.) under unfavorable environmental conditions of Donbass selected their most informative characteristics for a general assessment of the level of anthropogenic load on local ecotopes. Empirical criteria were calculated as a result of correlation analysis between data sets on the content of heavy metals in soil samples and the values of phytoindication indices.
Territories with arid climate are characterized by insufficient atmospheric humidification at high air temperatures. Therefore, the use of drip irrigation during the growing season of plants is an effective agrotechnical method of farming. However, its use causes a number of unfavorable consequences that can be avoided by using biological plant protection agents with pronounced biological activity against phytopathogenic bacteria, micromycetes, insects and viruses. These remedies are based on the introduction of microorganisms and their metabolites into the biotechnological process. A biological plant protection agent based on Bаcillus atrophaeus ACIM В–11474 has been developed and its effect on the mycocenosis of the studied soils when growing lettuce in the arid climate of the Astrakhan region using drip irrigation has been studied.
Аn attempt is made in this work to establish correlations between the level of enzymatic activity of the soil and factors of an abiotic nature. It was found that the activity of invertase and urease in the soils of more southern territories is higher than that of northern ones. In soils with a pH value of the soil environment close to neutral reaction, the level of enzymatic activity is higher than in more acidic ones. The most sensitive to soil acidity among the studied urease enzymes. In relation to zinc, an inverse correlation was established between its content in the soil and the level of invertase activity. According to the degree of resistance to salinity, the enzymes are arranged in the following order: catalase> invertase> urease. An increase in the mineralization of the soil solution leads to an increase in the activity of urease. Of the studied enzymes, the most labile are representatives of the class of hydrolases (invertase and urease), less labile are oxidoreductases (catalase). Thus, when diagnosing the state of the soil by the level of enzymatic activity, it is necessary to take into account the main abiotic factors affecting the activity of enzymes: the average annual air temperature; pH and mineralization of the soil solution; the content of substances that inhibit microorganisms and block exozymes.
The article provides the brief review of the literature and own works devoted to the peculiarities of the cereal embryonic organogenesis at the early stages of ontogenesis in the conditions of in vitro culture (the so-called somatic embryogenesis, or embryoidogenesis in vitro). Particular attention is paid to the issues of hormonal regulation of the development of somatic cereal embryos from initial cells to mature structures in vitro. A comparison of somatic embryogenesis in vitro with similar events in zygotic embryogenesis in vivo confirms the validity of the principle of universality of morphogenesis processes in vivo and in vitro (Batygina, 2014). The prospects of using somatic embryogenesis in vitro as a model for studying the most complex biological phenomenon – zygotic plant embryogenesis in vivo – are discussed.
Based on the analysis of ecotope schemes, the article attempts to delineate the ecotopic ranges of broad-leaved species on the eastern border of their geographical distribution within the subzone of broad-leaved dark coniferous forests. The term "ecotopic range of a species" is used, which means a set of ecotopes or types of habitats occupied by cenopopulations of a species. The article analyzes 3 ecotope schemes of the Ufa Plateau, on the basis of which the ecotopic areas of broad-leaved species are outlined. The author's scheme of ecotopes of the area of broad-leaved dark coniferous forests of the Southern Urals is presented and the ecotopic ranges of broad-leaved species in this area are outlined.
Methodological aspects of microclonal reproduction of valuable tree species – triploid aspen and Karelian birch, which are important for enriching the gene pool of the main forest-forming tree species in the Republic and obtaining high-quality wood raw materials in the form of ornamental and decorative wood, are proposed.
The study of plant adaptation mechanisms during the salt stress is required to provide an increase in plant productivity under such conditions. Along with a decrease in the availability of water for plants, the NaCL-induced inhibition of plant growth is associated with the toxic effect of sodium ions. The formation of apoplastic barriers due to the deposition of suberin and lignin restricts passive ion diffusion. However, the formation of such barriers reduces the capacity of the apoplastic pathway for water movement. In these conditions the role of transmembrane water transport is increased. This process is provided by aquaporin water channels. Thus the purpose of this work was to determine the contribution of aquaporins to hydraulic conductivity of peas plants under salinity-induced apoplastic barrier formation. An only slight decrease in plants transpiration caused by mercury chloride in the absence of salinization was in accordance with the ideas the apoplast is the dominant pathway when the Casparian bands is not formed yet. Salt stress in our experiments accelerated the development of the Casparian bands formation which could be visualized as an appearance of suberin strips in root endodermis which in turn was accompanied by a decrease in hydraulic conductivity. The decrease in hydraulic conductivity in 2 times during the mercury chloride treatment under salinity confirmed that contribution of aquaporins to the total hydraulic conductivity was increased under conditions when Casparian bands have had formed.
EFFECT OF THE COMPLEX OF ENDOPHYTIC BACTERIA BACILLUS WITH SALICYLIC AND JASMONIC ACIDS ON THE STATE OF THE PRO- / ANTIOXIDANT SYSTEM OF PLANTS AND THE RESISTANCE OF POTATOES WHEN INFECTED WITH LATE BLIGHT UNDER STRESS