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This review presents an analysis of the literature, which indicates the popularity of breeding methods in the fight against oomycete and fungal diseases of tomato: late blight (pathogen − Phytophthora infestans (Mont.) de Bary), fusarium wilt (pathogen − Fusarium oxysporum f. sp. lycopersici (Sacc.) Snyder and Hansen), early blight or alternariosis (pathogens − representatives of the genus Alternaria), cladosporiosis (pathogen−Cladosporium fulvum Cook.). Theoretical and practical achievements, the latest developments in genetics, molecular biology, plant physiology, microbiology are considered. Special attention is paid to modern information about the diversity of tomato pathogens, their morphological, genetic, physiological features, including racial composition; the presence of pathogen resistance genes in the gene pool of the culture under study, their mapping and the possibility of introduction into the genome from other sources; about the developed markers of target genes and loci of quantitative traits; the degree of associations between a molecular marker and a target gene; about the features of inheritance of the studied trait, as well as the possibility of pyramiding R-genes and QTL in one genotype. To accelerate and improve the efficiency of tomato breeding for resistance to pathogens, these issues are of great importance. Their study will strengthen the integration of modern biotechnology with the traditional breeding process, which is carried out by classical methods.

Relevance. The presented studies are aimed at obtaining new forms of tomato with a complex of genes for resistance to fungal diseases in combination with a standard type of bush and dark coloring of fruits based on marker-mediated selection.Methodology. The biological objects of the study are varieties and hybrid forms of tomato from the collection of the Michurinsky SAU. Molecular genetic analysis was performed using the following methods. DNA extraction was carried out from young leaves using a kit for isolation of NC Sample NC manufactured by Agrodiagnostika LLC according to the manufacturer's protocol. Fermentas production kits were used for PCR. Identification of the cladosporosis resistance gene was Cf-19 performed using the DNA marker R7. The presence of a fusarious wilting resistance gene was determined by a I-2/5 marker. The amplification results were visualized by agarose gel electrophoresis.Results. During the research, a collection of varieties and hybrid forms of tomato of the Michurinsky GAU was analyzed in order to identify genes for resistance to cladosporiosis Cf-19 and fusarium wilt I-2. A total of 52 genotypes were analyzed. It was found that most samples (41 samples) are characterized by a heterozygous state of the Cf-19 gene. All indeterminant and semi-determinant forms had both alleles. Of the 23 determinant forms presented in the collection, 10 had only one allele corresponding to recessive homozygote. Among all analyzed tomato genotypes, no dominant homozygous forms were noted. The study of the collection revealed several alleles of the I-2 gene. In total, four fragments corresponding to various alleles were amplified. A total of 50 resistant genotypes have been identified in the collection. Two alleys of the I-2 gene (633/693 bp) were identified in 42 tomato samples. Four varieties are homozygous in one allele (633 bp), which determines resistance. Three varieties have a second resistance allele (566 bp). One genotype has only an allele defining susceptibility (693 bp). On the basis of molecular analysis, as well as an assessment of the type of bush and fetal color, initial forms were selected with subsequent hybridization. 67 hybrid tomato plants were obtained. Evaluation of the presence of resistance genes showed that most of the resulting hybrids are resistant to cladosporiosis and fuzariosis. This is due to the presence of dominant alleles of Cf-19 and I-2 genes in a heterozygous state. Among the resulting hybrids, plants with a bark type of bush were identified. A total of 13 such plants were obtained.Conclusion. Thus, the work carried out allowed to obtain hybrid forms of tomato combine the signs of resistance to two pathogens of fungal diseases and the stem type of the bush. These forms are planned to be used in further selection work.

Background. Clonal apple rootstocks are one of the main components of intensive gardening. The degree of rootstock damage by fire blight affects the resistance of the variety–rootstock combination. The paper presents a study on marking quantitative trait loci (QTL) of resistance to fire blight Erwinia amylovora in clonal apple rootstock.Materials and methods. A collection of 20 rootstock forms was analyzed. For the study, SCAR markers GE-8019, AE10-375 and microsatellite marker CH-F7-FB1 were used.Results. Polymorphism was observed for all three markers, and their various combinations in one genotype were revealed. It was previously noted that genotypes that carry all three markers were more resistant than those that lack them. The presence of all three markers was observed only in forms 62-396 (В10), 16-1 and 2-9-102. The other genotypes did not have the GE8019 marker. The AE10-375 marker was identified in eight clonal rootstocks. Microsatellite marker CH-F7-FB1 was present in all tested rootstocks. However, polymorphism was detected there. Most genotypes had a 174 bp fragment, but a 210 bp fragment was identified in two of the 20 forms. Clonal rootstock 70-20-21 proved heterozygous for this marker. The analyzed collection also included samples that had only the microsatellite marker: G16, Malysh Budagovskogo, Paradizka Budagovskogo (B9), 54-118 (В118), 57-491, 70-20-20 (В119), 70-20-21, 71-7-22, 76-3-6, 83-1-15, 87-7-12, and 2-12-10. The study of rootstock forms on the basis of resistance to metabolites of the fire blight pathogen was carried out under laboratory conditions using the E. amylovora culture filtrate in vitro on leaf explants. Most of the studied genotypes had different combinations of markers. However, the experiments showed that forms 62-396 and 14-1 with two out of three markers (AE10-375 and CH-F7-FB1) phenotypically manifested the trait of resistance to metabolites of E. amylovora.

Background. Leaf mold, a disease caused by the fungus Cladosporium fulvum Cooke in tomato, is one of the reasons for a significant decrease in the fruit yield. The most reli­able and environmentally friendly way to protect tomato from diseases is the development of resistant cultivars and hybrids. The study of genetic aspects of disease resistance in plants is the basis of successful breeding work. Marker-assisted selection of the source forms of tomato is a rela­tively new approach in breeding, based on direct selection of plants for genes that determine the economically impor­tant traits. It allows for the time-saving analysis of breed­ing material.Materials and methods. The present work offers the results of screening more than 30 accessions from the genetic collection of tomato cultivars and hybrids of the Michurinsk State Agrarian University using the P7 molecular marker.Results and discussion. Polymor­phism of the Cf-19 gene of resistance to leaf mold was evalu­ated, and clear reproducible results were obtained. To test the marker, seven hybrid forms of greenhouse tomato were used. The reliable identification of the Cf-19 gene by using the P7 marker was confirmed through artificial infection with C. fulvum. Six out of seven hybrids demonstrated a high level of resistance to the pathogen, which is con­firmed by the originators’ data. A strong lesion was noted on the leaves of only one hybrid. The molecular genetic analysis has shown that among all control samples, only this genotype was a recessive homozygote. Besides, ac­cording to the originator, this genotype is not resistant to leaf mold. The performed test proves the high efficiency of the P7 marker. By using it, 35 genotypes were analyzed. The data obtained during the work show that the majority of the studied samples turned out to be heterozygous. At the same time, homozygous forms were also noted. For in­stance, the ‘Golden Rain’ tomato cultivar has only one 250 bp fragment, which corresponds to a recessive homo­zygote. Four genotypes were found to contain 300 bp frag­ments, which correspond to dominant homozygotes. The molecular genetic analysis revealed a number of genotypes that can be used as sources of resistance to leaf mold.

Abstract Subroutines for calculating the spectral and angular characteristics of infrared synchrotron radiation are developed. Corresponding calculations are carried out for a number of proton and electron accelerators. The results obtained enable methods to be developed for beam diagnostics as well as highly sensitive detectors of infrared radiation for remote contactless nondestructive diagnostics and for investigating bunches and high-speed processes in ring-type (CERN/SEPS-LHC) and linear (GSI bunch target) accelerators, and also the thermal fields in nuclear power plants. [ABSTRACT FROM AUTHOR]

Ante- and postnatal hypoxia significantly worsened the postnatal development of animals. The posthypoxic behavioral model included hyperactivity and decreased learning ability, these being typical manifestations of attention deficit disorder. A peptide constellation prevented and significantly improved posthypoxic postnatal development and eliminated the majority of negative behavioral changes. [ABSTRACT FROM AUTHOR]

The structure of cleaved mica particles and the influence of cleavage conditions on surface prop- erties of mica were studied by IR spectroscopy. [ABSTRACT FROM AUTHOR]

We studied immediate and delayed changes in ECG in female albino rats subjected to acute hypobaric hypoxia on days 4-5 of pregnancy and evaluated the possibility of correction of hypoxia-produced disturbances with some peptides. Acute hypoxia lengthened the mean RR interval, increased heart rate variability, and decreased the monotony index. Hypoxia induced considerable changes in the structure of ECG that reflected the development of arrhythmias and conduction disturbances. These changes in ECG persisted during the posthypoxic period. Intranasal administration of heptapeptides Semax and β-casomorphin-7 to pregnant females promoted recovery from acute hypoxia and normalized ECG in the posthypoxic period. [ABSTRACT FROM AUTHOR]

Abstract Changes in ECG parameters were studied in pregnant rats exposed to acute hypobaric hypoxia during the period of organogenesis (gestation days 9 to 10). Rats with low, medium, and high tolerance to hypoxia exhibited pronounced autonomic nervous system imbalance, which become apparent as a loss of correlation between various parameters of ECG signals recorded at rest and during exposure to some stress factors existing under normal conditions. [ABSTRACT FROM AUTHOR]

Conditions for the precipitation of phosphates from solutions of titanium(IV) sulfate containing iron(III) were studied. The precipitation of components and the mechanism of the phase formation in the system under study were considered in relation to the TiO2 : Fe2O3 ratio in the starting solution. [ABSTRACT FROM AUTHOR]

We studied the effect of exposure to acute hypobaric hypoxia in the progestational period on the content of biogenic amines in the brainstem and cerebral cortex in rat pups of different age. The possibility of correcting hypoxia-induced changes with regulatory peptides was evaluated. We found that early antenatal hypoxia disturbs maturation of catecholaminergic systems in the brain. It should be emphasized that the differences from the control varied depending on the age of rat pups. Single intranasal administration of Semax heptapeptides and β-casomorphine-7 to pregnant females prevented changes in the content of biogenic amines in CNS of the offspring during postnatal ontogeny. [ABSTRACT FROM AUTHOR]

Delayed consequences of acute hypoxia were studied in 60-day-old rat pups. The animals were exposed to acute hypobaric hypoxia on day 10 of embryogenesis. The offspring of intact females served as the control. Reactivity of mesenteric lymphatic vessels to norepinephrine was studied by vital microscopy. The frequency and duration of lymphatic vessel contractions in males significantly increased compared to the control. In females the duration of norepinephrine-induced lymphatic vessel contractions increased, while the frequency and amplitude of contractions and basal vascular tone did not differ from the control. [ABSTRACT FROM AUTHOR]