Wild grasses as the reservoirs of infection of rust species for winter soft wheat in the Northern CaucasusWild grasses as the reservoirs of infection of rust species for winter soft wheat in the Northern Caucasus

Common winter wheat is the main grain crop cultivated in the North Caucasus. Rust disease damage is one of the factors limiting wheat productivity. There are three species of rust in the region: leaf (Puccinia triticina), stem (P. graminis) and stripe rust (P. striiformis), and their significance varies from year to year. The most common is leaf rust, but in the last decade the frequency of its epiphytotic development has significantly decreased. At the same time, an increase in the harmfulness of stripe rust (P. striiformis) is noted. Stem rust in the region is mainly absent or observed at the end of the wheat growing season to a weak degree. Only in some years with favorable weather conditions its mass development is noted on susceptible cultivars. It is believed that the sources of infection with rust species in the North Caucasus are infested soft wheat crops, wild-growing cereals and exodemic infection carried by air currents from adjacent territories. In the North Caucasus, forage and wild grasses are affected by Puccinia species almost every year. Depending on weather conditions, the symptom expression is noted from late September to December and then from late February to May–June. Potentially, an autumn infection on grasses can serve as a source for infection of winter soft wheat cultivars sown in October. The purpose of these studies is to characterize the virulence of P. triticina, P. graminis, P. striiformis on wild cereals and to assess the specialization of causative agents to winter wheat in the North Caucasus. Infectious material represented by leaves with urediniopustules of leaf, stem and stripe rusts was collected from wild cereals (Poa spp., Bromus spp.) in the Krasnodar Territory in October–November 2019. Uredinium material from P. triticina, P. striiformis, and P. graminis was propagated and cloned. Monopustular Puccinia spp. isolates were used for virulence genetics analysis. In experiments to study the specialization of rust species from wild-growing cereals on common wheat, 12 winter cultivars were used (Grom, Tanya, Yuka, Tabor, Bezostaya 100, Yubileynaya 100, Vekha, Vassa, Alekseich, Stan, Gurt, Bagrat). These cultivars are widely cultivated in the North Caucasus region and are characterized by varying degrees of resistance to rust. Additionally, wheat material was inoculated with Krasnodar populations of P. triticina, P. striiformis, P. graminis from common wheat. In the virulence analysis of P. triticina on cereal grasses, four phenotypes (races) were identified: MCTKH (30 %), TCTTR (30 %), TNTTR (25 %), MHTKH (15 %), and five were identified in P. graminis (RKMTF (60 %), TKTTF, RKLTF, QKLTF, LHLPF (10 % each). Among P. striiformis isolates, three phenotypes were identified using the International and European sets of differentiating cultivars – 111E231 (88 %), 111E247 (6 %) and 78E199 (6 %). Using isogenic Avocet lines, 3 races were also identified, which differed among themselves in virulence to the Yr1, Yr11, Yr18 genes (with the prevalence of virulent ones (94 %)). Composite urediniums’ samples (a mixture of all identified races) of grass rust of each species were used to inoculate winter wheat cultivars. The most common winter wheat cultivars (75 %) were characterized by a resistant response when infected with P. graminis populations from common wheat and cereal grasses. All these cultivars were developed using donors of the rye translocation 1BL.1RS, in which the Lr26, Sr31, and Yr9 genes are localized. The number of winter wheat cultivars resistant to leaf rust in the seedling phase was lower (58 %). At the same time, all the studied cultivars in the seedling phase were susceptible to P. striiformis to varying degrees. The virulence analysis of the leaf, stem and stripe rust populations did not reveal significant differences in the virulence of the pathogens between wild-growing cereals and soft wheat. Urediniomaterial of all studied rust species successfully infested soft wheat cultivars. The results obtained indicate that grasses are rust infection reservoirs for common wheat crops in the North Caucasus

TITERS OF ANTIBODIES TO Β1-ADRENOCEPTOR AND M2 CHOLINERGIC RECEPTORS IN PATIENTS WITH VENTRICULAR ARRHYTHMIAS WITHOUT AN ORGANIC CARDIOVASCULAR DISEASE AND THEIR POSSIBLE CLINICAL SIGNIFICANCE

Aim. To identify the most promising epitopes that simulate various sites β1-adrenergic and M2-cholinergic receptors, and to evaluate their possible contribution to the development and maintenance of cardiac arrhythmias, particularly idiopathic ventricular arrhythmia. Material and methods. Patients with ventricular arrhythmias without organic cardiovascular disease (the study group; n=70) were included in the study. The control group consisted of 20 healthy volunteers. Evaluation of levels of antibodies to antigenic determinants, modeling various sites β1-adrenergic and M2-cholinergic performed in all patients. Causal treatment with clarithromycin and valacyclovir performed in part of patients. Results. Antibodies to different peptide sequences of β1-adrenergic and M2-cholinergic receptors have been identified in 25% of main group patients. A direct correlation between the frequency of episodes of ventricular tachycardia and IgG levels to MRI-MRIV (p=0.02) revealed. Increase in titre of antibodies to β1-adrenoceptors, to a peptide sequence β8 (p=0.02), and lower titers of antibodies to the M2 acetylcholine receptor — chimera MRI-MRIV IgM (p=0.06) and ARI-MRIV IgM (p=0.07) were observed when assessing the efficacy of the therapy in the causal dynamics in the group of "untreated" patients. IgG titer reduction of ARI-MRIV (p=0.02), which is 4 times out of 10 with reduction of ventricular ectopic activity , recorded after valacyclovir therapy. Clarithromycin therapy on the level of antibodies exerted no significant effect. Conclusion. Possible involvement of antibodies to β1-adrenoceptor and M2-cholinergic receptors in the development of idiopathic ventricular arrhythmias demonstrated. The relationship between the frequency of episodes of ventricular tachycardia and levels of antibody titers to M2-cholinergic receptors found. Attempt of causal treatment, depending on the possible mechanisms of the autoimmune process is executed. Further studies to confirm or refute the results to the larger sample of patients are needed

ТИТРЫ АНТИТЕЛ К β1-АДРЕНОРЕЦЕПТОРАМ И М2-ХОЛИНОРЕЦЕПТОРАМ У БОЛЬНЫХ С ЖЕЛУДОЧКОВЫМИ НАРУШЕНИЯМИ РИТМА СЕРДЦА БЕЗ ПРИЗНАКОВ ОРГАНИЧЕСКОГО ЗАБОЛЕВАНИЯ СЕРДЕЧНО-СОСУДИСТОЙ СИСТЕМЫ И ИХ ВОЗМОЖНОЕ КЛИНИЧЕСКОЕ ЗНАЧЕНИЕ

Aim. To identify the most promising epitopes that simulate various sites β1-adrenergic and M2-cholinergic receptors, and to evaluate their possible contribution to the development and maintenance of cardiac arrhythmias, particularly idiopathic ventricular arrhythmia. Material and methods. Patients with ventricular arrhythmias without organic cardiovascular disease (the study group; n=70) were included in the study. The control group consisted of 20 healthy volunteers. Evaluation of levels of antibodies to antigenic determinants, modeling various sites β1-adrenergic and M2-cholinergic performed in all patients. Causal treatment with clarithromycin and valacyclovir performed in part of patients. Results. Antibodies to different peptide sequences of β1-adrenergic and M2-cholinergic receptors have been identified in 25% of main group patients. A direct correlation between the frequency of episodes of ventricular tachycardia and IgG levels to MRI-MRIV (p=0.02) revealed. Increase in titre of antibodies to β1-adrenoceptors, to a peptide sequence β8 (p=0.02), and lower titers of antibodies to the M2 acetylcholine receptor — chimera MRI-MRIV IgM (p=0.06) and ARI-MRIV IgM (p=0.07) were observed when assessing the efficacy of the therapy in the causal dynamics in the group of "untreated" patients. IgG titer reduction of ARI-MRIV (p=0.02), which is 4 times out of 10 with reduction of ventricular ectopic activity , recorded after valacyclovir therapy. Clarithromycin therapy on the level of antibodies exerted no significant effect. Conclusion. Possible involvement of antibodies to β1-adrenoceptor and M2-cholinergic receptors in the development of idiopathic ventricular arrhythmias demonstrated. The relationship between the frequency of episodes of ventricular tachycardia and levels of antibody titers to M2-cholinergic receptors found. Attempt of causal treatment, depending on the possible mechanisms of the autoimmune process is executed. Further studies to confirm or refute the results to the larger sample of patients are needed.</p

PRINCIPLES AND METHODS OF WHEAT BREEDING ON TOLERANCE TO DISEASES IN KRIA NAMED AFTER P.P. LUKIYANENKO

The article deals with the principles, methods and study results of the development of winter wheat varieties, tolerant to the widely spread and harmful diseases. The article gives the characteristics of phytosanitary risks dangerous for the gross yields of wheat. The main trends of the breeding-immunological researches in the institute, materials and methods which are used in wheat breeding for their immunity have been presented here. The results of the complex immunological assessment of winter wheat varieties tolerant to leaf rust are discussed in the article. The molecular screening showed that the winter wheat varieties, developed in the institute, possessed different types of tolerance genetically determined by the nature. It was established that the commercial varieties possessed poorly effective genes of tolerance Lr1, Lr10, Lr26, Lr34 and their various combinations or ‘pyramids’. The article presents the classification of the varieties according to the degree of their infection with leaf rust that is of great importance for the breeding and the conducting of genetic monitoring of disease resistance, to optimize phytosanitary state in the wheat agro phytocenosis. It has been determined that the most efficient method to create the varieties tolerant to head fusarium is a complex hybridization, intended on the pyramiding of the genes with specific and unspecific resistance. The important thing of the breeding work is to carry out multiple selections in the hybrid populations, starting with F2 under artificial infection. Using such methods the new variety ‘Urup’ has been obtained and approved for use in the production

USE OF MOLECULAR MARKERS IN WHEAT BREEDING AT THE KRASNODAR LUKYANENKO RESEARCH INSTITUTE OF AGRICULTURE

Pilot experiments on molecular marker application in breeding of winter wheat at the Krasnodar Lukyanenko Research Institute of Agriculture (KNIISH) are described. The most efficient ways of marker application in creating new cultivars are outlined. A variety of genes responsible for valuable agronomic traits in KNIISH varieties have been detected