The main scientific achievements of the world famous Belarusian photosynthetic school, founded by T. N. Godnev and A. A. Shlyk, in the field of the study of the processes of chlorophyll biosynthesis, biogenesis and organization of the photosynthetic apparatus in plant organisms are presented. Particular attention is paid to the modern development of concepts of the biosynthesis of chlorophyll and the structural and functional state of photosynthetic membranes in the studies of Belarusian biophysicists specializing in photosynthesis. The scientific directions of research of current interest in the field of photosynthesis in the Republic of Belarus are characterized.

It has been studied the activity components of the antioxidative system in barley roots to five strains bacteria Bacillus genus treatment of seeds under salt stress. The data obtained allow to conclude that the higher resistance to salinity (4 % NaCl solution, 24 h) the root system of barley seedlings, which manifests itself in maintaining the speed of growth and development of roots under the action of Bacillus amyloliquefaciens (B. am.) 78 TM, Bacillus subtilis (B. s.) 7 MP and B. s. M 9/6 at a concentration of 105 cells/ml. The protective effect of strain B. am. 78 ТМ accompanied by a significant accumulation of proline, and in the recovery period the accumulation of hydrogen peroxide and increased superoxide dismutase and peroxidase. The protective action of strains of B. s. M 9/6 and B. s. 7 MP is due, in our opinion, significant accumulation of hydrogen peroxide and activation of antioxidant enzymes under stress, and in the period of adaptation the preservation of the high content of hydrogen peroxide compared with stress control.

The results of the analysis of genomic structure and allelic composition of the dwarf genes Rht-B1, Rht-D1, Rht8 and Ddw1 in 33 secondary recombinant lines (SRL) of hexaploid triticale with various types of D(A)- and D(B)- chromosome substitutions and 8 introgressive wheat lines with R(A)-, R(B)- and R(D)-chromosome substitutions are presented. It was found that in the overwhelming majority SRL genotypes contain the Rht-B1b allele in the homozygous state. Nine SRLs and all introgressive wheat lines are homozygous by the Rht-B1a allele; 4 lines are heterogeneous in the allelic composition of the Rht-B1 gene. The Rht8a allele (165 bp) was present in all the investigated SRLs, whereas the Rht8b allele (174 bp) was detected in introgressive wheat lines. Five introgressive wheat lines were heterozygous by the allelic composition of the Rht-D1 (Rht-D1a/Rht-D1b) gene. In three lines, along with the Rht-D1a/Rht-D1b genotype, plants homozygous for the RhtD1a and Rht-D1b alleles were found. No samples bearing the Ddw1 gene were identified. Based on the genotyping results, SRL of hexaploid triticale with the Rht-B1b gene ‒ promising for use in breeding for lodging resistance ‒ were selected.

The stimulating effect of 5-aminolevulinic acid (ALA) at a concentration of 200 mg/l on respiratory activity was established by accumulating non-covalently bound to the proteins heme and increasing the activity of the heme-containing enzyme cytochrome c-oxidase, as well as increasing the rate of oxygen absorption in the respiration of winter rape with high content of anthocyanin’s. The inhibitory effect of ALA on the structural organization and photosynthetic activity of the photosynthetic apparatus was revealed. A decrease in the level of photosynthetic pigments – chlorophyll a and b, reduction in protein content of chlorophyll-protein complexes of two photosystems, as well as decrease in the ability of plants to release oxygen were demonstrated.

The results show the effect of water extracts from dry biomass of adventive plant species with high invasive activity from Belarus on the growth of seedlings of test plants. High correlation between the effect of biologically active substances released from the seeds of Heracleum sosnowskyi Manden on various test plants and plant species is discussed. The strong stimulating effect of water extracts on plant species from Cruciferae family is shown. Plant species from Poaceae family are mainly characterized by a neutral reaction to the biologically active substances emitted from H. sosnowskyi seeds. It has been found that water extracts at the concentrations from 0.01 to 0.001 % have a stimulatory effect on the growth and development of test plants, while an inhibitory effect was observed at the concentrations in the range from 1 to 10 %.

Modern ideas about the preservation of the species diversity of the plant world characteristic of a particular region, especially in connection with the intensification of the use of plant resources and man-caused pollution of the growing environment, the increasing rate of anthropic dissemination, are more relevant to the field of rational nature management, protection of rare and endangered species than to the control of the spread of invasive plants and the unintentional (accidental) resettlement of introducers, which also follows landmarks be on economic objectives, taking into account the balance of the permissible volume of use plant resources and the ecology. The use of, for example, in agriculture and (or) forestry, the practice of road and green construction, the gardening of settlements of some invasive species, including introduced ones, is no less (and sometimes even more) effective than the use of native plants. Depending on the aims and methods of research, the degree of study and the size of the surveyed area (the range of natural distribution of a representative of the plant world), as well as the subjective understanding of the processes of settlement, migration of species and the formation of vegetation cover, there are different approaches to the terminological basis of concepts of adventive (invasive and introduced) plants.

Thiamine oxidation chemistry in presence of metmyoglobin and hydrogen peroxide is quite complex and different products can be formed. Incubation of thiamine with metmyoglobin and hydrogen peroxide can result in splitting of thiamine molecule at carbon atom of the methylene bridge and production of aminopyrimidine and thiazole components as separate molecules or in formation of thiochrome, thiamine disulfide, oxodihydrothiochrome, and thiaminethiazolone. Oxidative transformation of thiamine phosphate esters in presence of metmyoglobin and hydrogen peroxide gives similar products however thiaminase activity, i.e. splitting of the molecules into aminopyrimidine and thiazole phosphate parts, is much higher in this case. Addition of tyrosine or paracetamol to incubation mixture inhibits thiaminase activity and formation of disulfides, but yield of thiochrome or thiochrome phosphates increases. Identification of products of thiamine (or its phosphate esters) oxidation in the presence of metmyoglobin and hydrogen peroxide was performed using HPLC, mass-spectrometry and spectral-fluorescent methods. Role of oxoferryl forms of myoglobin in degradation of thiaminediphosphate, cofactor of the important enzymes of carbohydrate metabolism, by thiaminase mechanism is discussed.

The results of a comparative study of the effect of complete mineral fertilizers and growth stimulators Nanoplant, Hydrohumate and Ecosil on the main characteristics of the pigment fond of the assimilating organs of two- and three-year (brephic and nobilous) plants of the two model varieties V. corymbosum L.− Bluecrop and Northland are presented. Significant genotypic, age and intervariant differences in the character and degree of response of plants to tested agrotechnologies have been revealed. It has been shown that the sexually mature blueberry plants were characterized by a higher content of photosynthetic pigments in the leaf tissue than the juvenile ones, against the background of differences in the rates of their accumulation when fertilizers were using. Substantial shifts in the composition of the carotenoid complex were revealed on a high agrophone, due to the extremely activation of β-carotene, biosynthesis in the degradation of xanthophylls, which increased with age of plants. In juvenile plants, the integral stimulating effect of fertilizers on the formation of the fond of plastid pigments was manifested only in the Northland variety with the highest efficiency of application of N₁₆P₁₆K₁₆ and the least of the treatments with Nanoplant and at a divergence of the degree of their positive influence in 20.9 times. The effectiveness of the application of Ecosil and Hydrohumate was inferior to that of N₁₆P₁₆K₁₆, respectively, by 1.4 and 2.2 times. Bluecrop has an insignificant positive effect on the content of plastid pigment in leaves only on the background of N16P16K16 with an absolute dominance of the inhibitory effect on it of other types of fertilizers. In plants that have reached puberty, a substantial leveling of varietal differences in the degree of sensitivity of the pigments in plastids to the use of fertilizers has been established. In contrast to juvenile plants, due to the more pronounced activation of β-carotene biosynthesis in them, the combined effect in both varieties of blueberry on the fertilized agro background was extremely positive. The most significant positive changes in the rate of accumulation of photosynthetic pigments in both varieties of blueberry were provided by the addition of N₁₆P₁₆K₁₆ and Hydrohumate, while the least significant ones were processed by Nanoplant (from Bluecrop) and EcoSil (from Northland).

By the response of the peripheral blood of experimental Wistar rats to the combined action of γ and laser radiation, the radioprotective effect of laser radiation was studied. Four series of experiments were carried out, in each of which the whole body of rats was irradiated once with γ-radiation (dose 3 Gy). Low-intensity laser exposure was performed in the form of blood overvein irradiation (NLOK), which differed in the different series of experiments by the number of procedures, the laser radiation density (6.25 J/cm², 2.5 J/cm2, 1.25 J/cm² ) and the exposure sequence: before and after γ-irradiation. The concentration of hemoglobin, hematocrit, the number of erythrocytes, leukocytes, lymphocytes, platelets were determined. Along with the study of the effect of laser radiation on the radiation changes in hematological parameters, changes were also analyzed: the activity of antioxidant defense enzymes (superoxide dismutase and catalase). It is shown that laser radiation tends to compensate the effect of γ-radiation, which caused leukopenia and lymphopenia. Significant differences in the individual radio sensitivity of blood samples of individual rats were revealed. For blood constituents and antioxidant defense enzymes, it was demonstrated the dependence of the quantitative changes caused by laser and γ-radiation on the initial indices.

 

The physicochemical methods have been used to study the effect of soil tillage of typical black soil for the state of water and the restructuring of intermolecular bonds that determine the of the superstructure of humic acids (HA). It have been established that the HA of the virgin soil is more heterogeneous in composition, due to the presence of hydrophobic and hydrophilic domains, that is due to the equilibrium of the conjugated processes of accumulation and decomposition of soil organic matter (SOM), while tillage of typical black soil caused losses of SOM. It was found that plowing increases the content of fulvic acids and the amount of free water and hydroxyl and carboxyl groups of HA, due to the increase the biodegradation of SOM, which promotes the labile SOM and release of more nutrients. It have been established that plowing of typical black soil leads to conformational rearrangement of intermolecular interactions in the superstructure of HA by hydrophilic hydration. Polar structural elements coordinated by free water dipoles with accessible carboxyl groups. They stabilized the new conformation of HA mainly by hydrogen bonds. It has been shown that the 9-year use of No till leads to a decrease in free water, due to the greater availability of non-polar aromatic structures, and to the reduction of unavailable hydrophilic components, which causes the conformation of the superstructure of HA to stabilize mainly by hydrophobic forces, which causes the accumulation of a hard-to-degradable conservative SOM. Transmission electron microscopy (TEM) have been revealed the presence of smaller particles in the HA samples, in contrast to the sample of HA by No till, which is due to the difference in the molecular organization of their humic superstructures.

 

Water metabolism indicators of leaves Q. robur and Q. rubra in artificial planting and trees at a distance from him wascompared . Found that the leaves Q. robur of separately growing trees is characterized by predominantly higher intensity of transpiration in all months of the study than Q. rubra. Planting both types in the vast majority of measurements of water evaporation is less significant than in the separately growing trees in a clearing. Noted that in September, the figures of evaporation of water is the highest relative to the previous time of measurement. Was observed the fall of this indicator in the hottest period of the day, as in July, indicating deterioration of the water loss regulation. The Q. robur leaf water deficit in plants of open space is bigger than in planting in all studied periods. In Q. rubra, the figure bigger in the planting. A comparison of leaves water deficit both species separately growing trees indicates that it is smaller in Q. rubra than in Q. robur, it is consistent with a more intense return of water by Q. robur leaves. But planting despite more intense transpiration and lower water-holding capacity from Q. robur has conversely situation. During all periods of the study water-storage capacity is higher in the Q. rubra leaves than in Q. robur. However, the relative turgescence in Q. robur leaves the highest in the plantations, in Q. rubra this figure the biggest in separately growing trees, which can be explained by the fact that this indicator depends not only from evaporation, but also to a large extent on the flow of water through the root system.

Small non-coding RNAs (sncRNA) are short RNA molecules that are involved in gene expression, posttranscriptional modifications and cell immunity regulation. The most studied and the most interesting for the medical application classes are small interfering RNA (siRNA), microRNA (miRNA) and piwi-interacting RNA (piRNA). SncRNAs have a wide range of functions. Primary function of siRNA and miRNA is silencing of gene expression by binding or/and degradation of messenger RNA. PiRNA also have this function but its principal function is control of genome stability on the basis of blocking the activity of transposons. Many diseases, such as cancer, diabetes, neurological, and cardiovascular diseases are accompanied by distortion of sncRNA expression. Abnormal sncRNA expression profile can be used as a hallmark to determine certain type of cancer. In all types of cancer were discovered deviations in the sncRNA pool. From the medical point of view sncRNA can be used as disease marker or as a component of gene therapeutic drugs. In the case of markers usage sncRNAs deserve attention as universal and relatively stable samples. But frequently sncRNAs differ just by few nucleotides, which can create difficulties in their distinguishing. In the frame of gene therapy sncRNAs are able to silence theoretically any gene expression. As sncRNA affects mRNA but not DNA it allows avoiding accidental changes in the genome. In this case delivery systems for RNAs are highly needed, because sncRNAs are unable to penetrate the cell membrane and can be degraded by blood enzymes. Despite of existing problems, sncRNAs are promising compounds for the diagnosis and therapy of wide range of diseases.

The main scientific achievements of the world famous Belarusian photosynthetic school, founded by T. N. Godnev and A. A. Shlyk, in the field of the study of the processes of chlorophyll biosynthesis, biogenesis and organization of the photosynthetic apparatus in plant organisms are presented. Particular attention is paid to the modern development of concepts of the biosynthesis of chlorophyll and the structural and functional state of photosynthetic membranes in the studies of Belarusian biophysicists specializing in photosynthesis. The scientific directions of research of current interest in the field of photosynthesis in the Republic of Belarus are characterized.