Background. One of the most important tasks faced by the scientists of Krymsk Experiment Breeding Station of VIR is the long-term preservation of the stone fruit gene pools (over 1,000 genotypes of 44 species) collected during plant explorations. It is much more difficult to preserve representatives of the wild flora than cultivars, due to their ecological specialization to specific environments and the need to create conditions for their successful development. This aspect concerns, first of all, such species as Louiseania pedunculata (Pall.) Pachom., L. ulmifolia (Franch.) Pachom., Prunus cocomilia Ten., P. brigantiaca Vill., Armeniaca sibirica (L.) Lam., Padus ssiori (F. Schmidt) C.K. Schneid., and some others.

Methods. The studies were carried out in the collection plantations of the field genebank at Krymsk Experiment Breeding Station of VIR according to VIR’s guidelines. Accessions of wild stone fruit species were the objects of the studies.

Results. Many years of field research into ex situ conservation of introduced wild species proved the efficiency of stone fruit cultivation in tub culture and a modified technique of dense planting with crown formation according to the “border-hedge” pattern. It takes into account biological characteristics of genotypes shaped in natural areas, the use of own-root or grafted plants on clonal rootstocks of various growth rates depending on their life form (tree or shrub), resistance to biotic and abiotic stressors, soil and terrain requirements, and the tasks posed before researchers. The recommended planting schemes (2.5–4.0 × 0.5–1.0 m) significantly reduce the area occupied by the same number of plants in conventional cultivation patterns and cut down power and labor inputs into technological practices.

Background. Natural populations of fruit and small fruit plants in Belarus and their specific and varietal composition for a long time attracted the attention of pomologists and breeders. Identification and mobilization of unique local forms and landraces as genetic sources of useful traits as well as monitoring duplicate collections will contribute to their more effective use in breeding practice to develop competitive domestic cultivars of various crops and reveal the adaptability of foreign cultivars to the conditions of Belarus.

Methods. The itinerary of the collecting mission passed through 6 regions of the Republic of Belarus (Gomel, Minsk, Mogilev, Vitebsk, Brest, and Grodno) in 2012–2017.

Results. As a result, 221 samples of fruit, small fruit and nut plants were collected, including 18 rootstocks of fruit crops. By 2021, 105 unique landraces were tested in the plant introduction and quarantine nursery and planted in the field gene bank, including 28 accessions of apple, 33 of pear, 11 of sour cherry, 5 of sweet cherry, 9 of plum, 8 of apricot, 1 of almond, 2 of hazel, 3 of garden strawberry, 1 of black chokeberry, 1 of viburnum, and 1 of bird cherry. There are plans to use the obtained accessions in breeding practice as
sources of valuable agronomic traits (high winter hardiness, high yield, resistance to a set of plant pathogens, etc.).

Background. Using LD₅₀ concentrations of the osmotic PEG 6000 to select millet genotypes during seed germination for drought resistance breeding is the best way of millet genotype differentiation according to the studied trait.

Materials and methods. The millet cultivars ‘Omriyane’, ‘Kharkovskoe 57’, ‘Konstantinovskoe’, ‘Slobozhanskoe’, and the accession IR 5 were selected as the test material. Water stress was applied through five concentrations of PEG (6000 MW): 11.5%, 15.3%, 19.6%, 23.5%, 28.9%, and 0.0% (control). On the sixth day of incubation, millet seed germination was measured. The regression method for assessing LD₅₀ (half-lethal dose) by V. B. Prozorovskii was used to theoretically substantiate the selection of an optimal osmotic concentration, which would be most accurate in identifying the level of drought tolerance in millet genotypes during seed germination.

Results and conclusions: The 15.3% to 28.9% concentrations of PEG 6000 solutions had a negative effect on seed germination of millet genotypes. A strongly suppressed seed germination rate was observed at the PEG concentration of 23.5%: germination percentage in all cultivars (except for IR 5, with 56.0%) fell below 50%. Calculations according to the Verhulst logistic curve and the probit analysis by V. B. Prozorovskii’s technique showed that the mean LD₅₀ concentration of PEG 6000 solutions for all studied genotypes was 23.03%. Thus, as a result of the analysis of our experimental data and their statistical processing, we recommended the 23.0% concentration of PEG 6000 solution as the most differentiating in terms of drought resistance in the millet seed germination phase.

Background. Various approaches are used for identification of the most resistant fruit crop cultivars, including the analysis of different physiological and biochemical indicators. In Krasnodar Territory, Russia, one of the major stressors in summer is the hydrothermal stress. Drought and heat lead to an oxidative stress, as reactive oxygen species are produced in plant cells. Plants respond to oxidative damage by activating antioxidant enzymes, such as superoxide dismutase, catalase, and various peroxidases. Peroxidase is able to decompose hydrogen peroxide. Peroxidase activity was calculated under natural summertime changes in the hydrothermal pattern (control) and in simulated high-temperature conditions.

Materials and methods. Three apple cultivars of Russian breeding, ‘Fortuna’, ‘Soyuz’ and ‘Prikubanskoe’, and cv. ‘Ligol’ of Polish origin were studied. In the summers of 2018–2019, their leaf samples were analyzed to assess peroxidase activity and its isozyme composition under control and stress conditions. Native electrophoresis in polyacrylamide gel was used for separation of peroxidase isoforms. Malondialdehyde content was measured to identify oxidative stress levels in apple leaves.

Results. The tested indicators demonstrated a high degree of heterogeneity induced by both cultivar specificity and seasonal weather dynamics. Peroxidase isoforms with a molecular weight of 70 to 60 kDa, characterized by the maximum level of variability (1–4 isoforms), were isolated. Two other groups included 1–3 isoforms with a molecular weight of ~130–100 kDa, and one with a molecular weight of ~55 kDa. The highest enzyme activity was found in cvs. ‘Fortuna’ and ‘Soyuz’ in July 2018, the hottest month during the period of research. Under simulated conditions, the triploid cultivar ‘Soyuz’ was least susceptible to the stress impact.

Background. Studying essential oils in conifers is of great scientific and practical interest due to their high bactericidal properties. Their volatiles play an important role in combating pathogenic microflora and removing harmful microorganisms from the air, thus benefiting human health. Conifers are highly effective as part of parklands and urban landscaping.

Materials and methods. Pinus radiata D. Don, P. sabiniana Douglas and P. coulteri D. Don grown on the Southern Coast of Crimea were studied. Essential oil was extracted from pine needles by hydrodistillation on Ginsberg devices, and its component composition was analyzed using gas–liquid chromatography on a 6890N system with a 5973N mass selective detector.

Results. Among the studied species, P. radiata manifested high essential oil content in needles: 0.15% on the wet weight basis (0.36%, dry weight). Under the conditions of the southern coast of Crimea, the major essential oil components in P. radiata were β-pinene (29.5% of the total essential oil), α-pinene (21.2%) and limonene (12.4%); in P. sabiniana, phenylethyl butyrate (20.5%), limonene (15.2%) and α-pinene (13.7%); in P. coulteri, β-pinene (11.6%), δ-cadinene (11.0%) and α-pinene (10.6%). In the essential oil of P. radiata monoterpenes dominated (74.9%); in P. sabiniana, monoterpenes (38.7%) and their derivatives − alcohols (25.3%) and esters (20.5%); in P. coulteri, sesquiterpenes (38.2%) and monoterpenes (28.8%).

Conclusion. The essential oils of P. radiata and P. sabiniana under different climate conditions contained mostly monoterpenes (β-pinene in P. radiata, and α-pinene in P. sabiniana) and their derivatives. The component composition of P. coulteri essential oil was the most variable, with a general tendency towards the predominance of sesquiterpenes and diterpenes; the ratio between those groups and the qualitative composition of sesquiterpenes both varied.

Background. Resistance of raw and boiled tuber flesh to darkening when potato is processed into potato-based products or consumed directly is an important requirement for new potato cultivars. Identification of hybrids resistant to tuber flesh darkening would contribute immensely to future breeding work.

Materials and methods. Parent forms and hybrid progeny of potato were tested for five years (2016–2020) in Kirov Province using the methods and technologies approved for potato breeding process. The progeny of 10 cultivars used as pollinators was analyzed.

Results and conclusions. Cultivars with high levels of resistance to the darkening of raw tuber flesh were selected in the collection nursery. A total of 62 accessions (or 24%) out of 256 were identified for the absence of darkening or only small traces thereof (8 points) in raw tubers. Medium and strong darkening of the flesh (4–5 points) was recorded for 45 accessions. Analyzing the progeny of pollinator cultivars showed an increased occurrence of hybrids resistant to tuber flesh darkening in the progeny of cv. ‘Manifest’: 71% of the studied hybrids had non-darkening flesh (9 points). Manifestation of tuber flesh darkening was found to depend on weather conditions during the growing season: the higher was the air temperature, the weaker was the darkening of raw tuber flesh, but when the soil moisture during tuberization was high, tuber flesh became more darkened. A statistically significant relationship was observed between the darkening of boiled tubers and the content of crude protein (r = 0.74) and vitamin C (r = 0.79). Hybrid 179-10 was identified for high productivity (32.5 t/ha) and crude protein content (1.54%), while the highest resistance to the darkening of raw and boiled potato tubers was registered in hybrid 72-13.

Background. Crop yield is a compound and complex character in breeding programs. A stable high yield is determined by the genotype, environmental impacts, and their interaction. A comprehensive assessment of cultivars based on their adaptability, plasticity and stability makes it possible to select among the studied assortment the most promising, potentially high-yielding and environmentally flexible plant forms adaptable to a wide range of environmental conditions.

Materials and methods. Evaluation of 146 accessions representing two-row (subsp. distichon L.) and six-row (subsp. vulgare) barleys (Hordeum vulgare L.) was performed in 2015–2017 to measure the adaptability, stability, plasticity and homeostasis of barley yield. Experimental data were statistically processed using the methods of the two-way ANOVA and correlation analysis.

Results and conclusion. It was established that barley yield formation was almost equally determined by the genotype (34.3%), environmental conditions (31.9%), and genotype × environment interactions (33,7%), showing that the tested barleys were relatively well adaptable to climate changes in the Northern Trans-Urals. Barley yield was more closely associated with grain weight per plant (r = 0.72) and the number of productive stems per area unit (r = 0.63), and to a lesser extent with seed germination rate in the field (r = 0.39) and 1000 grain weight (r = 0.37). Strong correlations were observed for the yield with the adaptability coefficient (r = 0.94), environmental plasticity index (r = 1.00), and compensatory capacity (r = 0.96). Cvs. ‘Abyssinian 14’ (k-23504, var. pallidum) and ‘Kharkovsky 70’ (k-23683, var. nutans) exhibited a set of adaptive and productive properties.

Fifty narrow-leaved lupine accessions of various origin from the VIR collection were studied in Minsk District, Republic of Belarus, and described by a set of morphobiological, biochemical and molecular-genetic characters. According to the results of field and laboratory studies, 10 promising accessions were selected. They are recommended for use in regional breeding programs and included in the working collection of the Belarusian State University.

The results of studying the collection of North American apple-tree species are presented. Forms with a whole set of traits interesting for breeding are highlighted, including such features as late flowering schedule, disease resistance, long shelf life of fruits, etc. In addition, the small-fruited ornamental apple-tree (crab apple) accessions obtained from North American species are briefly described, and the most valuable of them are recommended for practical uses.

Background. Linseed oil is a versatile product with varying biochemical composition. Linseed breeding is aimed at producing cultivars with different chemical properties in their oil. The crop is widespread but the environment has a great effect on its fatty acid  biosynthesis.

Materials and methods. The impact of weather conditions on the variations in fatty acids composition was studied. Twenty linseed cultivars and accessions of diverse origin and with varying oil composition from the VIR collection were grown in Tomsk Province in 2016–2018. The content of 15 fatty acids (lauric, myristic, palmitic, palmitoleic, margaric, stearic, oleic, cis-vaccenic, linoleic, linolenic, arachidic, eicosenic, arachido nic, behenic, and lignoceric) was assessed in linseed oil using gas–liquid chromatography.

Results. The tested material presented a wide diversity of genes controlling different steps of fatty acids biosynthesis and genetic mechanisms involved in the responses to the changing environment. The analysis of variance proved that the content of oleic, linoleic, linolenic and lignoceric acids was controlled solely by the genotype. The content of palmitic and stearic acids was influenced by both the genotype and environment. The synthesis of lauric and cis-vaccenic acids was significantly affected by the weather. Practically all acids, except linoleic and linolenic ones, showed a very high random variation, which in our experiment included genotype × environment interaction. The accessions differed in the range of variation in their characters under diffe rent conditions. There was no definite regularity in the hanges of fatty acid content in the tested genotypes during 3 years.

Conclusion. The assessed genotypes probably possess different regulatory mechanisms for fatty acid biosynthesis. Thus, they present a diverse stock for further investigations into fatty acid biosynthesis and for the development of new linseed cultivars widely adaptable to environmental conditions.

Background. Downy mildew (DM) caused by the fungus Plasmopara halstedii (Farl) Berl. & De Toni) is one of the most harmful diseases of sunflower (Helianthus annuus L.). Due to the pathogen’s attacks, annual seed harvest losses range between 30% and 70%. Lines resistant to new races of the pathogen should be obtained for the development of commercial sunflower hybrids.

Materials and methods. Downy mildew resistance of 323 lines and 10 cultivars from the sunflower collection was assessed in the field at the Kuban Experiment Station of VIR in 2017–2018. Line VIR 845, susceptible during all years of observations, was used as a control. Resistance genes were identified by means of the molecular analysis using diagnostic markers of the Pl_arg, Pl₆ and Pl₈ genes that confer resistance to many known P. halstedii races.

Results. The founder varieties of VIR’s lines were susceptible to a varying extent. Thirty-nine lines were resistant in 2016 and 2018; among those, 36 lines were susceptible in 2017. Presumably, a more virulent P. halstedii race became widespread in 2017, compared to the races that prevailed in 2016 and 2018, so the genes that determined resistance in 2016 and 2018 turned out to be ineffective. Lines ТА 716-18, VIR 768, and VIR 800, having originated from interspecific hybrids, exhibited absence of pathogenic damage during 3 years of the trials. Molecular markers of the Pl_arg, Pl₆ and Pl₈ genes were detected in most lines that demonstrated resistance in 2016 and 2018. There were no markers in lines VIR 768 and VIR 800, whereas in ТА 716-18 the markers of Pl_arg and Pl₈ were present.

Conclusion. As a result of the long-term studies, a trait-specific genetic collection was established for sunflower. It comprises genotyped lines with various effective DM resistance genes. Lines ТА 716-18, VIR 768 and VIR 800 appeared highly resistant to the pathogen and probably possess new resistance genes/alleles introgressed from wild species.

Background. The peanut is one of the most important oil crops suitable for cultivation in the tropical areas of the world. Despite its agronomic importance, few studies have been carried out to assess the morphogenetic diversity of Arachis hypogaea L., especially in East African countries. The major interest of this morphologic study lies in the potential of this species to provide useful genes for the improvement of cultivated peanuts. To date, no study has been performed in Algeria to characterize local peanut varieties.

Materials and methods. Thirty peanut accessions were collected from four principal areas of peanut production in Algeria. Genetic characterization using 15 agronomic characters and 25 morphological descriptors showed a high level of diversity among accessions. Principal Component Analysis and the Hierarchical Ascendant Classification were made to clarify the genetic relationship between peanut accessions.

Results and discussion. Results showed that leaflet size (length and width), seed shape and size, oil content, and branching pattern were the principal characters to discriminate the screened A. hypogaea accessions. In addition to that, the weights of 10 pods and 100 seeds were the most variable traits and presented a CV of 42.53% and 40.12%, respectively. On the other hand, total storage proteins extracted were separated using SDS-PAGE and revealed thirty bands that were used to generate a matrix and make a cluster analysis using the UPGMA method, exhibiting different storage proteins compositions. Moreover , the phenotypic diversity observed agrees with the storage protein profile diversity, while the accessions grouped in similar clusters belong to the two subspecies of A. hypogaea. The results of the current study show that morphological traits and seed storage proteins can be useful for exploring the diversity among A. hypogaea accessions.

Background. One of the promising sources for enrichment of the common wheat (Triticum aestivum L.) gene pool with new alleles is synthetic hexaploid wheat (SHW), or allopolyploids from crossing tetraploid wheats (2n = 4x = 28, BBAA) with accessions of Aegilops tauschii Coss. (2n = 2x = 14, DD), and subsequent doubling of the chromosome number in the hybrids. Objectives of the study were to evaluate the SHW accessions from the VIR collection for resistance to Puccinia triticina Erikss. populations collected in Russia; genotype the accessions; and summarize information from the published sources concerning the resistance of the studied accessions to other harmful diseases and pests.

Materials and methods. Resistance of 36 SHW accessions from the VIR collection to the populations of P. triticina was assessed in the laboratory and in the field, under artificial infection pressure, using the techniques developed by the Institute of Plant Protection. A phytopathological test and PCR markers were used to identify the Lr genes.

Results and conclusion. The SHW accessions were characterized according to their resistance to the Russian populations of the wheat leaf rust pathogen. The sources of resistance in the phase of emergence and in adult plants were identified. The phytopathological test isolated three accessions with Lr23; the PCR marker of Lr21=Lr40 was found in 11 accessions, Lr39=Lr41 in 19, and Lr22a in 3. At the same time, k-65496, k-65515 and k-65517 had si multaneously Lr21=Lr40 and Lr39=Lr41, while k-65497, k-65503 and k-65508 had Lr22a and Lr39=Lr41. The analysis of published data showed that many of the studied SHW accessions were also resistant to other harmful diseases and insect pests, so they are of interest for further studying and possible use in domestic breeding.

Background. In 1991, under the cooperation agreement, the Federal Center of Agriculture Research (FCAR) of the South-East Region received the first improved accessions from the International Center for Agricultural Research in the Dry Areas (ICARDA). The objective of this work was to study the source material developed under comparable conditions of dryland agriculture and include the best accessions in scientific breeding programs.

Material and methods. The presented data resulted from the study of spring durum wheat cultivars and lines from ICARDA (Aleppo, Syria), conducted in 1991–1998. Accessions with the best indicators of grain quality, adapted to the conditions of the Lower Volga, were selected and included into the crossing program. Grain analysis was carried out using the conventional methods for durum wheat as well as those modified by the Spring Durum Wheat Breeding Laboratory of the FCAR of the South-East.

Result and conclusion. Many years of work led to identifying 22 lines of spring durum wheat, selected in the breeding nursery of the Main Competitive Trails (MCT) and in different years involved in complex multistep hybridization. The spring durum wheat cultivar ‘Lilek’ was included into the State Register for Selection Achievements in 2009, while cv. ‘Tamara’ was submitted to the State Variety Trials in 2020.

Background. There are three species cultivated in Russia: Cucurbita pepo, C. maxima, and C. moschata, the latter being the most thermophilic among them. Cultivars of C. moschata are grown in southern regions, where a growing season of no less than 110–130 days is required. C. moschata has no bushy cultivars suitable for cultivation. The aim of this study was to search for, identify and develop source material of C. moschata for breeding early-ripening bushy and short-vined cultivars.

Materials and methods. Accessions from the VIR collection, advanced cultivars, hybrids and lines of various generations served as research material. The study was based on the guidelines for studying and maintenance of the collection and for cucurbit crop breeding.

Results. Source material was identified for breeding practice: early accessions (90–98 days) possessing high productivity and fruit quality, with good taste, namely ‘Early Butternut’, ‘Butternut’, ‘Waltham Butternut’; accession k-3549, ‘Orekhovy’, and accession k-4235; and mid-early accessions (104–105 days) ‘Palov-kadu’, and ‘Aydzu Аkkikudza’. They exceeded in productivity the early-ripening reference (cv. ‘Mariya’) by 26.7–130%, and matched the reference in fruit quality. Hybrids from the crosses of vined accessions with the bushy form KL 745 were studied. Bushiness is inherited monogenetically and controlled by the recessive bu (bush) gene. Identified for breeding were early (93–95 days) bushy lines (KL) with a stem length of 0.8–1.2 m: KL 648, KL 652 and KL 656. Their productivity was within 4.2–4.5 kg per plant (higher than the reference by 40–50%). In fruit quality they were on the reference level. Early (92–98 days) short-vined lines (KPL) were identified, with a stem length of 1.3–2.0 m: KPL 168, KPL 640 and KPL 680; their productivity ranged 4.9–6.8 kg per plant, and their fruit quality was good or excellent.

Background. Microsatellite (SSR) markers are now widely used both for studying genetic diversity in fruit crop collections, including apple (Malus × domestica Borkh.), and for genotyping individual accessions. The apple collection held by VIR, being the largest in Russia, contains cultivars bred at five experiment stations of VIR. These cultivars not only meet the requirements of horticulture in the region of their origin, but also are interesting as sources of valuable traits for breeding programs. However, these cultivars have not previously been studied using microsatellite markers. Materials and methods. A set of 10 SSR markers (CH02c02b, CH03d01, CH01f03b, CH02d08, CH02c02a, CH05e03, CH02c09, CHVf1, CH01h01, COL) was used for genotyping 35 apple cultivars developed at VIR and four parental forms. Fluorescently labeled PCR products were separated by capillary electrophoresis on ABI Prism 3130xl.

Results. In 35 apple cultivars from VIR, 97 alleles were identified at ten studied loci. The number of alleles per locus varied from 5 (CH02c02b) to 17 (CH02c02a). The frequency of unique alleles was 26,8%, with 12,4% for rare alleles. Polymorphism information content (PIC) values varied from 0,49 (CH02c02b) to 0,91 (CH02c02a) and averaged 0,76. Expected and observed heterozygosity levels averaged 0,79 and 0,56, respectively. Cluster analysis did not reveal a clear division of cultivars according to the place of origin (experiment stations of VIR), but revealed clustering according to pedigrees.

Conclusion. A high level of polymorphism was observed in 35 apple cultivars from VIR using ten SSR markers. The obtained data on the allelic composition of the studied cultivars can be used for their identification and contribute to more efficient collection  management. Further studying and SSR genotyping of VIR’s apple collection and comparison with the data obtained in the presented work can help to identify the origin of cultivars with unknown pedigrees.

Background. Identification of spectacular ornamental perennial lianas for urban landscaping in southern cities is important for modern urban greening programs. The aim of this work was to study flowering peculiarities of Japanese honeysuckle (Lonicera japonica Thunb.).

Materials and methods. The target material was honeysuckle plants growing in the environments of Southern Uzbekistan. Observations were conducted in 2019–2020 using conventional approaches.

Results and conclusion. The inflorescence of L. japonica is an open dibotryoid, with flowers arranged along the lateral axes of the first order. Flowers are bisexual, zygomorphic. Blossoming of flowers in inflorescences occurs acropetally. The flowering period is almost 150–170 days (starts in April and lasts until the end of August). Dichogamy in the form of proterandry is observed in honeysuckle flowers. The male flowering phase comes the first. It starts 1.5–2.0 hours after the opening of the corolla and ends with the drying of the stamens. The corolla turns yellow 36 hours after the blooming of the flower and the stamens begin to dry out. This is the female phase. Over the next 84 hours, the pistil begins to dry out slowly, but the corolla of the flower lasts up to 96 hours. The duration of the female flowering phase is 60 hours. L. japonica is of considerable interest for vertical landscaping of urban communities. Plants remain ornamental for a long time. Studying this species as an essential oil plant is promising, since it contains a significant amount of germacrene D.

Background. Narrow-leaved lupine (Lupinus angustifolius L.) is an important high-protein forage and green manure crop, also promising for food use. This is a plastic species produced under various ecogeographic conditions and the only cultivated species of lupine adapted to high northern latitudes – up to 60° NL. Gradual expansion of lupine production areas led to the accumulation of pathogens, damage to lupine crops by harmful organisms, and significant harvest losses. Breeding and cultivating resistant varieties is the most profitable and environmentally sound way to control diseases and pests. Studying the species composition of pathogens and searching for source material are the necessary stages of plant breeding for immunity.

Materials and methods. A set of 101 accessions of L. angustifolius from the VIR collection were studied in the northwest of the Russian Federation (Pushkin, St. Petersburg) in 2019, and 62 accessions from the same set in 2020. Mycological examination of the affected leaves was carried out on potato sucrose agar medium under laboratory conditions. The degree of damage to plants by diseases and infestation by pests was assessed during the period of flowering, fruit formation and ripening using point scales.

Results and conclusions. A wide range of harmful organisms were identified for their negative impact on the growth and development of narrow-leaved lupine plants. The dominant pest was the lupine aphid (Macrosiphum albifrons Essig), discovered in Russia for the first time. A whole set of fungal pathogens was identified, among which the most common and harmful were the causative agents of Fusarium, brown leaf spot, powdery mildew, gray mold, and Sclerotinia stem rot. Narrow-leaved lupine accessions with weak degrees of pathogenic damage were selected.

Background. Yellow rust (Puccinia striiformis West.) is a harmful disease of cereal crops. Significant yellow rust in cidence has systematically been registered on VIR’s experimental fields in Derbent (Dagestan) and Pushkin (North western Russia). Resistance assessment and subsequent selection of resistance sources for breeding require proper monitoring of the virulence in the pathogen’s local populations. The purpose of this work was to characterize the virulence of P. striiformis on VIR’s experimental fields in Derbent and Pushkin, and use molecular markers to find out whether the studied P. striiformis isolates belong to any of the most dangerous invasive groups PstS1 and PstS2.

Materials and methods. In Derbent, leaves with uredinio pustules were collected from bread and durum wheat accessions; in Pushkin, from bread wheat and triticale plants. The pathogen’s virulence was analyzed in the laboratory using the world and European sets of differential cultivars, and isogenic Avocet Yr lines. In 2020, the resistance of differential sets was tested in the field in Derbent under a high natural infection pressure. SCAR markers were used to identify the invasive PstS1 and PstS2 isolates. 

Results and conclusion. A total of 18 phenotypes (races) of striiformis were identified (4 in Derbent, and 14 in Pushkin). The Yr5, Yr10, Yr15, Yr17, Yr24 and Yr26 genes manifested high effectiveness in both locations. In the field, immune responses were observed in the Avocet lines with the Yr5, Yr7, Yr8, Yr10, Yr15, Yr24 and YrAR genes, and in the differential cvs. ‘Vilmorin 23’, ‘Moro’, ‘Reichersberg 42’, ‘Heines Peko’, ‘Nord Desprez’, ‘Compare’, ‘Carstens V’, ‘Spaldings Prolific’ and ‘Heines VII’. Moderate resistance was recorded for the line Jupateco 73R (damage up to 5%), and cvs. ‘Heines Kolben’ and ‘Strubes Dickkopf’ (5–10%). Using molecular markers, 2 isolates from the invasive group PstS2 were identified in the Pushkin collection of P. striiformis.

Background. The greenbug (Sсhizaphis graminum Rondani) can significantly reduce the yield of barley and other cereals in the southern regions of Russia. Cultivation of resistant varieties can significantly limit the pathogen’s harmfulness. At the same time, specific interaction with the genotypes of the host plant, characteristic of S. graminum, requires a continuous search for new resistance donors to broaden the genetic diversity of barley cultivars. 

Materials and methods. The resistance of 178 accessions of barley landraces from Uzbekistan to the Krasnodar greenbug population was tested in laboratory experiments. Juvenile plants were infested with aphids of different ages, and when the susceptible control died (cv. ‘Belogorsky’), resistance was assessed on a 0 to 10 (plant death) rating scale. Plants with a damage rate of 1–4 points (up to 30% of the leaf surface being damaged) belonged to the resistant class; damage rate of 5–8 points indicated moderate resistance of plants, and that of 9–10 meant susceptibility. In addition, we assessed the aphid damage of the winter barley cultivar ‘Post’, protected by the previously identified resistance gene Rsg1.

Results and conclusions. We identified 52 barley accessions as heterogeneous for the studied trait. In six accessions, plants with high (points 3 to 4) and moderate (5 to 8) resistance were identified; 6 accessions were differentiated into 3 phenotypic classes: resistant, moderately resistant, and susceptible; and in 40 accessions the manifestation of the resistance component varied within 5 to 7 points (from 31 to 60% of the leaf surface being damaged). The distinctly expressed resistance of 12 accessions is controlled by alleles of resistance genes that differ from Rsg1. After selection for resistance, the identified accessions can be used in breeding.

The forthcoming 134th birthday of Nikolai Vavilov has in spired the editors to publish the essay The Man Standing on the Globe written by Dr. Margarita Vishnyakova as the introductory article to the Spanish translation of Vavilov’s Five Continents (Cinco continentes). This book was published in 2015 by Libros del Jata S.L., a small publishing company in Bilbao, Spain. Margarita Vishnyakova was directly involved in the process of publication. She was acquainted with Dr. Gustavo Renobales, a former professor of botany at the University of the Basque Country, who became the book’s editor and publisher. As soon as the publishing process was initiated, Gustavo sought Margarita’s aid. She helped to overcome formalities associated with copyright and assisted with translation and selection of illustrations, also contributing to the solution of some botanical and linguistic problems (Vishnyakova, 2017). It took two years to finalize the publication. This essay was published only in Spanish. The original Russian version is presented here.