The collection of the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR) harbors 3,633 accessions of durum wheat landraces from 49 countries. This is a unique heritage, currently neither cultivated in the places of its origin nor found in any collection over the world. This review explores the history of the collection of landraces, its structure, and diversity of the preserved genotypes. Descriptions of landraces from different countries and examples of their successful utilization in breeding practice are presented. Special attention is paid to the collection of Russian landraces. Today, the problem of utilizing obsolete local cultivars is relevant in the context of the shrinking diversity of modern cultivars and genetic erosion of the source material for breeding. Innovative methods based on the use of molecular markers demonstrate new trends in the study and utilization of landraces in different regions.

   Background. Black and red currant berries are high-vitamin dietary products and important raw materials for healthy food production.

   Materials and methods. Berries collected from promising cultivars and elite seedlings of black and red currant from the genetic collection of the I.V. Michurin Federal Science Center were analyzed. Chemical composition and total antioxidants were assessed in 2017–2022 with analytical instruments at the Biochemistry and Food Technology Laboratory according to standard
techniques.

   Results and discussion. Berries of the studied black currant genotypes accumulated 16.3 % Brix of soluble solids, 10.0 % of sugars, 2.47 % of organic acids, 117.3 mg/100 g of vitamin C, and 201.4 mg/100 g of anthocyanins. Black currant cv. ‘Aksinya’ was the best in chemical composition (the long-term average sugar content was 13.3 %, organic acids amounted to 1.97 %, vitamin C to 156.7 mg/100 g, and anthocyanins to 257.4 mg/100 g) and manifested high antioxidant properties (92.4 mg/100 g of gallic acid). Red currant berries contained 12.0 % Brix of soluble solids, 7.7 % of sugars, 1.69 % of organic acids, 34.0 mg/100 g of vitamin C, and 57.3 mg/100 g of anthocyanins. Red currant cv. ‘Gazel’ and elite seedling 30-7-58 were identified for more than 40 mg/100 g of vitamin C in their berries, while elite seedling 27-13-42 had the highest amount of anthocyanins (above 100 mg/100 g) and high antioxidant properties (45.7 mg/100 g of gallic acid). The identified sources are recommended for fresh consumption, functional food production, and further breeding efforts.

   Background. The effect of heavy metal ions can cause ionic stress in plants – the problem of significant interest among researchers. This study was dedicated to the evaluation of genetically modified regenerated soybean lines obtained on nutrient media with heavy metal ions as a mutagenic factor.

   Materials and methods. Genetically modified regenerated soybean lines were tested at the Agricultural Biotechnology Laboratory and Soybean Breeding Laboratory, Federal Scientific Center of Agricultural Biotechnology of the Far East named after A. K. Chaika, and at the Agricultural Product Processing Laboratory, All-Russian Research Institute of Soybean.

   Object of the study. Fifteen regenerated soybean lines and source cultivars (‘Primorskaya 13’, ‘Primorskaya 301’, ‘Primorskaya 81’, and ‘Hodson’) served as the research material.

   Results. Soybean accessions promising for further breeding were selected on the basis of their useful agronomic traits, grain quality, and resistance to fungal diseases. Accessions R 1490 (0.41 kg/m²) and R 1606 (0.38 kg/m²) were identified for having the highest yield in the experiment. Accessions R 1568 (1000 seed weight was 200.0 g) and R 1609 (190.2 g) had the largest seeds. Accessions R 1584, R 1568 and R 1606 manifested complex resistance to fungal diseases under natural conditions, while accession R 1490 was the most resistant under artificial infection pressure. The experiment resulted in selecting a group of lines regenerated from cv. ‘Hodson’ with high content of protein, histidine, valine, methionine, and cysteine. Accessions R 1605 and R 1609 demonstrated the highest oil content. The study revealed changes in the proportions of unsaturated fatty acids С_18:2/С_18:1 in all regenerant groups.

   Basil (Ocimum basilicum L.) is a vital aromatic crop widely utilized in culinary and fragrance industries. The present study was conducted to implement a two-year field experiment (2019 and 2020) aimed to assess the impact of various fertilizers on the growth, yield, and essential oil composition of basil cultivated in Thanh Hoa Province, Vietnam. The fertilizer treatments included: no fertilizer (control), chemical fertilizer (NPK at 90-120-90 kg/ha), cow manure, chicken manure, and a combination of chemical fertilizer, cow manure, and chicken manure. The application of fertilizers resulted in significant improvements across various parameters compared to the control group. Basil plants treated with fertilizers exhibited increased height, la teral stem count, fresh and dry yields, chlorophyll and carotenoid content, essential oil yield, and essential oil content. The essential oil extracted from basil contained notable volatile compounds, with methyl chavicol, linalool, β-elemene, and epi-α-cadinol identified as the major constituents. The proportions of these compounds varied among the fertilizer treatments. Notably, the combined fertilization approach involving chemical fertilizers, cow manure, and chicken manure emerged as the most effective and significant in promoting basil growth and essential oil production. These findings not only contribute to the optimization of basil cultivation practices but also provide insights for the agricultural community, emphasizing the importance of balanced fertilization for maximizing the quality and yield of basil essential oil in the Vietnamese context.

   Background. A study of morphological, anatomical and physiological parameters of plants obtained as a result of introgressive breeding is important for assessing the prospects of their further use.

   Materials and methods. Spring bread wheat plants of cv. ‘Dobrynya’ and a set of introgressive wheat lines with Аegilops columnaris Zhuk. genetic material were studied. The area of flag leaves was measured. Preparations of macerated leaf tissue were used to analyze mesophyll parameters. Spectrophotometric techniques were applied to determine the composition of photosynthetic pigments in the flag leaf.

   Results and conclusion. A negative effect of substitutions of chromosomes 2A, 5B, 6A and 6D for chromosomes of the U and X genomes on the size of the flag leaf area was disclosed. There were no significant differences in cell shape and size among the lines and in comparison with the recipient cultivar. Changes in the content of pigments in flag leaf laminae have been recorded. Increased content of all groups of pigments was observed in the lines containing substitutions 6A(6G), 6B(6X) and 5B(5X)6A(6X). Substitution 2A(2U) led to a decrease in the level of chlorophyll, the ratio of chlorophyll a to b, and the ratio of chlorophyll to carotenoids.

   Background. Salt stress reduces water supply and causes ionic imbalance in the plant, eventually leading to a decrease in plant growth, functional activity, and productivity. Variable salinity levels in the field make it difficult to select salt-tolerant cultivars, so a need for other testing methods arises.

   Materials and methods. The plant material consisted of two own-rooted Vitis vinifera (L.) genotypes: cv. ‘Asma’, and hybrid M. No. 8-08-8-4 (‘Kok Pandas’ × ‘Zeibel 6357’). Salt stress was simulated by treating with NaCl at 0, 50, 80, 100, and 120 mM concentrations. Water status was measured by the leaf water potential (Ψ) using a pressure chamber. Changes in the leaf area
and total root length were assessed in vitro.

   Results. Salt stress affected growth characteristics and yield structure of both own-rooted vines, but hybrid M. No. 8-08-8-4 was more sensitive. The hybrid showed greater yield reduction (38.6 %) than cv. ‘Asma’ (28.4 %), while the mass concentration of sugars was higher in ‘Asma’. The greatest differences in the predawn leaf water potential were observed for ‘Asma’ and M. No. 8-08-8-4 on the 45th day of irrigation with water containing different NaCl concentrations. The root length of the more salt-tolerant cultivar reduced in vitro to a greater extent.

   Conclusion. The functional abilities of a cultivar depend on the level of salinization and the genotype. Cv. ‘Asma’ demonstrated higher salt tolerance compared to hybrid M. No. 8-08-8-4. Leaf water potentials characterizing the water status of plants were measured. The responses to salinization were the same in the vines grown in vivo and in vitro, so it is possible to perform testing for salt tolerance in vitro.

   Background. The problem of improving barley (Hordeum vulgare L.) grain quality, in particular grain protein content, is of practical importance for breeding.

   The objective was to select high-protein genetic sources of spring barley for breeding new cultivars and search for possibilities of predicting grain protein content according to the chlorophyll content in leaves.

   Materials and methods. The studies were conducted in 2018–2020 on 28 barley genotypes of different ecogeographic origin in accordance with conventional methods. Grain protein content was assessed using near-infrared spectroscopy, and chlorophyll content was measured spectrophotometrically in acetone leaf extracts using the method: Chlorophylls and carotenoids: measurement and characterization by UV-VIS spectroscopy.

   Results and conclusion. Average grain protein content significantly correlated with the amount of precipitations (r = 0.67), the sum of effective temperatures (r = 0.75) and the hydrothermal coefficient (r = 0.76) during the growing season. Genotypes with high grain protein content, high test weight, and grain uniformity were selected. Accessions k-30574 and k-30256 showing high yields and resistance to lodging are promising for the development of high-protein cultivars. Accessions k-15619, k-30379 and k-31046 demonstrated high plasti city in their protein content parameters. Accession k-5983 was characterized by consistently high grain protein content. Statistically significant correlations between chlorophyll content in the flag leaf and grain protein content were found in a set of accessions with environmental plasticity (b_i) values lower than 1.0 (r = 0.585…–0.645). A decrease in protein content was observed in extensive-type accessions with increased pigment content in leaves (r = –0.643 and –0.638 for Chl a and Chl b, respectively; r = –0.645 for the total chlorophyll). A high Chl a/b ratio may serve as an indicator of higher grain protein content levels in such genotypes (r = 0.585).

   Background. The fungus causing tan spot on wheat leaves, Pyrenophora tritici-repentis (Ptr), continues to expand its range and inflict severe damage to the crop. Development of resistant cultivars remains the most effective and environmentally friendly way of disease control.

   The objective was to characterize modern domestic cultivars of bread wheat (Triticum aestivum L.) according to their seedling resistance to geographically different Ptr populations, identify sources of Ptr resistance, locate the presence of dominant Tsn1 alleles in cultivars, and assess their relationship with Ptr susceptibility.

   Materials and methods. Ptr resistance was assessed in 76 winter bread wheat cultivars from the VIR collection, and 4 winter and 43 spring bread wheat cultivars from the Volga region. Isolates from the Krasnodar, Tambov, Tatarstan and Altai Ptr populations (2022) served as the inoculum. Dominant Tsn1 alleles were identified by PCR using the Xfcp623 marker.

   Results. Bread wheat cultivars were characterized for the type of response in the leaves of their seedlings to isolates from Ptr populations and the presence/absence of dominant Tsn1 alleles. Resistance to isolates from two or three Ptr populations was observed in 11 winter and 13 spring cultivars. Differences between winter and spring forms in their resistance levels were
shown. Dominant Tsn1 alleles were identified in 26 cultivars. No statistically significant association was found between the presence/absence of dominant Tsn1 alleles and the manifestation of resistance/susceptibility to Ptr.

   Conclusion. The disclosed diversity of bread wheat cultivars in their responses to the infection with isolates of different Ptr populations may be due to their differences in the alleles of Ptr resistance/susceptibility genes as well as the presence of still unknown effector genes in the pathogen’s genome. Cultivars resistant to two or three Ptr populations can be used by breeders as sources of seedling resistance.

   Background. Interspecific hybrids between the Ussuri plum (Prunus salicina subsp. ussuriensis (Koval. et Kost.) Erem.) and bullace (P. domestica subsp. insititia (Jusl.) Schneid.) were studied to discover causes of their low yields. A possibility is shown to use interspecific diploid hybrids in plum breeding for resistance to asphyxiation in snow-rich regions of Siberia.

   Materials and methods. The research materials included interspecific hybrids: Ayskaya (2n = 16), six Ayskaya seedlings (2n = 16, 24), and TSG No. 8 (2n = 32); Ussuri plum cv. ‘Altayskaya Yubileynaya’ (2n = 16), and bullace 18-119 (2n = 48). The research was conducted in 2004–2023 in the forest-steppe zone of the Ob river region in Altai. Conventional cytological and
cultivar-testing methods were used.

   Results and conclusion. The yield of the Ayskaya and TSG No. 8 interspecific hybrids strongly depended on mean daily temperatures during blossoming (r = 0.77 ± 0.26 and r = 0.74 ± 0.27, respectively) when compared to the Ussuri plum. Fruit trait segregation in the Ayskaya seedlings was specific to diploid plums – variations in fruit weight (5.6–27.6 g), skin color (violet, claret, red, and yellow), and flesh color (yellow, red, and green). Most fruit traits of the seedlings were similar to those of their maternal form. The content of polyaperturate pollen in polyploids (25.0–37.9 %) was much higher than in diploids (less than 1.4 %), which means that this trait makes it possible to identify polyploids in the progenies of interspecific plum hybrids. Diploid form 12-04-309 (pollen fertility: 45.9%) was selected as a source of asphyxiation resistance for diploid plum breeding, and tetraploid form TSG No. 8 (pollen viability: 24.2 %) for hybrid blackthorn breeding.

   Background. Spring oats play an essential role in the search for a comprehensive solution of urgent problems associated with the development of a solid fodder resource base that could meet the need of animal husbandry for high-quality feeds. Adequate animal feeding is possible when high-quality fodders are available and the rations are well balanced in basic nutrients.

   Materials and methods. Field studies were conducted in Tyumen Province on the experimental field of the Research Institute of Agriculture for the Northern Trans-Ural Region in 2016–2023. The tested materials included spring oat cultivars and breeding lines, with cv. ʻTalismanʼ serving as the reference. Productivity was assessed according to the harvested dry matter, crude and digestible protein, crude and digestible fat, crude and digestible fiber, and crude and digestible nitrogen-free extracts (NFE). To do this, the yield of green biomass in the phase of milky ripeness was taken into account, and the contents of dry matter and nutrients in it were measured.

   Results. Promising breeding lines were evaluated for their fodder productivity (green biomass yield and the collected dry matter, protein, fat, fiber, and NFE). Digestible energy value of the tested oats was calculated in feed units (FU) and in joules of metabolizable energy (ME) and gross energy (GE). Energy digestibility (ED) and concentrations of digestible energy (DE) and
metabolizable energy (ME) were measured.

   Conclusion. Cvs. ʻTobolyakʼ, ʻRaduzhnyʼ and ʻSiriusʼ were the best in fodder productivity. Cvs. ʻMegionʼ, ʻOtradaʼ, ʻFomaʼ, ʻTobolyakʼ, and line TM 07-95-16 were identified for the highest digestible energy value. They provided 0.85–0.86 FU per 1 kg of dry matter and formed 835.5–842.5 kJ of ME and 1708.1–1734.6 kJ of GE per 100 kg of dry matter. Their ED was 63.5–65.8 %, with 1092.87–1141.36 kJ/kg of DE and 896.15–935.91 kJ/kg of ME.

   Background. Sweet cherry plants bear fruit annually, are high-yielding, and generate good profits. Cultivars with early-ripening fruits are specially valued. Cultivation of such sweet cherries makes it possible to extend the period of fresh fruit consumption and increase the profitability of orchards. It is therefore relevant to breed new early-ripening cultivars of this fruit plant.

   Materials and methods. Twenty sweet cherry forms from five hybrid families obtained with in vitro embryo culture techniques at the Nikita Botanical Gardens were analyzed. The original early-ripening cultivars included in the hybridization of ‘Durona di Vignola 2’ and ‘Zemfira’ were used as a control. Flowering dates, fruit ripening dates, fruit weight and quality, resistance to negative temperatures (down to –25.6°C), and susceptibility to fungal diseases were studied from 2012 to 2021 at the Steppe Horticulture Laboratory, Nikita Botanical Gardens, using conventional methods.

   Results and conclusions. Late-flowering breeding forms 460, 597, 602, 612 and 843 were selected for their lowest susceptibility to the effects of late spring frosts. Forms 343, 366, 453, 459, 460, 602, 612, 653, 353, 387, 600, 653 and 843 had early and very early fruit ripening periods. Forms 320, 434, 460, 593a, 597, 600, 601, 602 and 607 were identified for their high yields. Genotypes 459, 460, 601 and 843 demonstrated resistance to Cylindrosporium hiemale Higg., and 597, 843 and 320 to Monilia cinerea Bonord. High winter hardiness and frost resistance was observed in forms 355, 434, 459, 597 and 602. Breeding forms 460, 602 and 843 were identified as promising for a set of traits (late flowering, large high-quality fruits, resistance to major diseases, and high yield). They are of interest for introduction into horticultural production and use in further breeding work to develop new competitive cultivars.

   Background. Barley grain contains such flavonoid compounds as proanthocyanidins. Despite their positive effect on plant adaptation to environmental conditions, they can worsen the quality of raw materials used in barley products. In this context, releasing proanthocyanidin-free cultivars is an important task. Mutants at the Ant25, Ant26 and Ant27 loci with unknown molecular functions can be used as donors of recessive alleles of the genes specifically controlling proanthocyanidin synthesis in barley grain. This study explored the effect of these loci on barley plant growth and development. A conclusion was made about their functional role in the biosynthesis of flavonoids and the expediency of using such mutants in the breeding of proanthocyanidin-free cultivars.

   Materials and methods. The weight of grains, roots and shoots, the length of the main shoot, and the number of lateral shoots were measured in mutants and original cultivars grown in a hydroponic greenhouse. The harvest index was calculated as the ratio of grain weight to total plant biomass. Differences between genotypes were assessed using the Mann–Whitney U-test.

   Results. The ant25.264 and ant27.488 mutants showed lower values of all analyzed characters than the parental cultivars ‘Secobra18193’ and ‘Zenit’, respectively. The ant27.2043 mutant had a shorter main shoot, less grain weight, and lower harvest index compared to cv. ‘Arena’, but did not differ from the original cultivar in other characters. Mutants at the Ant26 locus demonstrated no differences from the parental cultivar ‘Grit’ in all parameters, except the ant26.486 mutant whose root weight exceeded the cultivar’s value.

   Conclusion. The effect of the Ant25 and Ant27 loci on plant growth and development was proved. Mutants at the Ant26 locus, with no negative effect on plant development, may be recommended to barley breeders as promising donors for the development of proanthocyadin-free cultivars.

   Background. Fraxinus excelsior L. is a common forest species in the Central Russian Upland, used to produce valuable lumber and for landscaping. Mass mortality of this species due to fungi and insects determines the relevance of its detailed research. Tree crown development features play an important role in the tree’s life in both dense communities and open spaces.

   Materials and methods. Shoots and large branches were collected from the apical part of the crown for ten years in Belgorod and Leningrad Provinces. The lengths of internodes and shoots, the numbers of leaves and branchings, and shoot development patterns were analyzed. An unmanned aerial vehicle was employed to examine the treetops. The complexes of large branches on the crown periphery in different age states (g1, g2, and g3) were studied both by direct measurement and using photographs. The effect of temperatures on the length and number of leaves was assessed with a two-way analysis of variance (ANOVA).

   Results. Shoots of F. excelsior are significantly shorter at high mean temperatures in the second ten-day period of June. The number of leaves on them is significantly greater at high temperatures in the second ten-day period of May. Six-to-eight-leafed shoots make up the ascending part on the curve of the sequence of internode lengths for the most developed shoots. In ontogenetic states g1 and g2, the crown surface is represented by sections of large branches. In the g3 state, they break up into complexes of small weakly branching spherical structures. The apical branches of the umbrella-shaped crown of generative ash trees are inverted cone-shaped shoot complexes with a similar development pattern.

   Conclusion. The structure and development of F. excelsior branches characterizes the ecological features of the species, manifested through the absence of obvious branching orders and combined with the inverted conical shape of large branches.

   Background. Special attention is paid in many regions to invasive plant species introduced into natural plant communities. Studying the degree of naturalization of Berberis aquifolium Pursh and Daphne laureola L. on the Crimean Peninsula is important because these species are currently observed in different types of forest vegetation, including Protected Areas.

   Materials and methods. Forest plant communities with B. aquifolium and D. laureola served as the research target. A geobotanical survey was conducted in 2019–2021 using the Braun-Blanquet approach. The JUICE platform and the PC-ORD 5.0 algorithm were employed to perform the cluster analysis, and the PAST 3.26 software for the ordination analysis. Twelve factors were considered: soil humidity (Hd), humidity fluctuation (fH), substrate acidity (Rc), anionic composition (Tr), carbonate content (Ca), nitrogen content (Nt), granulometric (mechanical) composition of the substrate (Ae), illuminance of the community (Lc), thermal regime (Tm), aridity/humidity (Om), cryoregime (Cr), and climate continentality (Kn). Phytoindication technique was used to determine the parameters of ecological niches.

   Results and conclusion. The communities with B. aquifolium and D. laureola on the Southern Coast of Crimea were found to belong to the Quercetea pubescentis and Erico-Pinetea classes of vegetation. The species appeared to be most widespread in the pine-oak-hornbeam and oak-hornbeam-dogwood forest communities where they occurred mainly along riverbeds, near springs, and along gully bottoms. According to a majority of edaphoclimatic factors, their habitat conditions corresponded to the parameters of the fundamental niches for the studied species, which explains their high degree of adaptation to the natural environments on the Southern Coast of Crimea.

   A case study of 33 cenopopulations (South Urals, and Central Yakutia) and 8 herbarium specimens of Valeriana L. was used to make a comparative analysis of qualitative (fruit shape, color, and pubescence) and quantitative (fruit length, width, and length-to-width ratio) morphological characters, and 1000 fruit weight among the species Valeriana officinalis L., V. alternifolia Ledeb., V. dubia Bunge, V. wolgensis Kazak. and V. tuberosa L. Fruits of V. officinalis were found to be relatively light and small, those of V. alternifolia and V. tuberosa were relatively heavy, and those of V. wolgensis were large. Fruit indices (length-to-width ratios) of V. officinalis and V. wolgensis were higher than 2, while those of the remaining species were about 2. Dependence of fruit size characteristics on altitudes, latitudes, and weather conditions was shown. Intrapopulation variability of morphological features in fruits was, as a rule, low or very low. Fruit length variability was lower in most species than the variability of their fruit widths or fruit indices. The contribution of interspecific variability to the variation in the quantitative traits of fruits exceeded the contribution of interpopulation variability. Qualitative and quantitative fruit characters of Valeriana L. spp. can be used as additional taxonomic indicators for their differentiation. The keys are provided for identification of species according to their fruit characters.

   The village of Ugolnye Kopi (Anadyrsky District, Chukotka Autonomous Area, Russia) is located in the left-bank estuary part of the Anadyr River, on the shore of the Anadyr Firth, overlooking the Bering Sea. Despite a relatively low latitude (64°44’N), more suitable for the development of boreal vegetation, the effect of cold-sea air masses on the environments of this locality forms vegetation more typical of the Subarctic tundra subzone. Penetration of adventive plant species, human satellites, into this area is very limited. There has been no previous information about the composition of the synanthropic flora at Ugolnye Kopi Village. Some data concerning adventive plants in the vicinity of the town of Anadyr were available in the review published by N. A. Sekretareva and A. A. Korobkov from the Komarov Botanical Institute. A survey conducted in August 2021 resulted in identifying an adventive component of the flora in the vicinity of Ugolnye Kopi, consisting of 44 vascular plant species. A key role in the village’s spontaneous landscaping has been played by 18 species of apophytes that arrived and settled there from the surrounding vegetation. Seven more apophytic species came to the village from more distant places of Chukotka. The usual synanthropic component, long ago acclimatized in Chukotka, is represented by 7 species: Hordeum jubatum, Chenopodium prostratum, Descurainia sophioides, Erysimum boreale, E. cheiranthoides, Taraxacum ceratophorum, and T. officinale s.l. Invasive species alien to this area are Elytrigia repens, Puccinellia borealis, Oberna behen, Stellaria media, Boechera pendula, Capsella bursa-pastoris, Trifolium repens, Lappula anisacantha, L. heteracantha, Lepidotheca suaveolens, Senecio dubitabilis, and S. vulgaris.

   Development of productive strawberry cultivars adapted to harsh winter conditions is an urgent task for plant breeders in Russia. The M. G. Safronov Yakut Scientific Research Institute of Agriculture has used wild strawberry forms combining several useful agronomic and biological traits, primarily the resistance to extreme environmental conditions, to achieve this objective. In the efforts to preserve the diversity of crop cultivars, the N. I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR) has developed and is implementing a program to establish nomenclatural standards for domestic cultivars of vegetatively propagated crops. The results of the implementation of this program are presented. Nomenclatural standards for the strawberry cultivars ‘Alexandra’, ‘Pokrovskaya’, ‘Sadovospasskaya’, ‘Vladyka Zosima’ and ‘Bersenevskaya’, released by the M. G. Safronov Yakut Scientific Research Institute of Agriculture, have been formalized, registered in the VIR Herbarium Database, and placed for conservation in the Herbarium of Cultivated Plants of the World, Their Wild Relatives, and Weeds (WIR).

   Background. Phytophthora infestans (Mont.) de Bary is a well-known pathogen affecting potato plants. Due to the changes in the pathogen population, the late blight disease caused by P. infestans is still difficult to manage. Economic losses are caused by the susceptibility of potato foliage or tubers to late blight, and both expressions of susceptibility are often not interconnected. Potato cultivars resistant to P. infestans are still too few to ensure reduction of harvest losses.

   Material and methods. In total, 682 potato cultivars and 20 hybrid clones from the VIR collection were screened in field and laboratory tests. They were assessed by conventional techniques. A score scale of 1–9 points was used both in the field and the laboratory, with 9 corresponding to disease resistance.

   Results. The results showed high infection pressure in the field during all four growing seasons of the experiment. The degrees of damage on the foliage varied from 1 to 8 points. The percentage of cultivars with strongly damaged foliage ranged from 55 % in 2020 to 66 % in 2023. From 17 % to 23 % of cultivars were assessed as moderately susceptible. The fact that many cultivars of various origin manifested compatibility with the local population of P. infestans during four growing seasons confirms its high and stable pathogenicity. Cultivars with high (points 7–8) or moderate (point 6) resistance were identified across the four years of testing. The part of the cultivars recognized as resistant earlier in 2017–2019 appeared to be moderately resistant or moderately susceptible in 2020–2023. Laboratory tests succeeded to identify genotypes with tuber resistance to late blight.

   Background. European plum (Prunus domestica L.) is a widespread stone fruit crop in Krasnodar Territory and Adygea. Development of fungal diseases, including brown rot, shot hole, red leaf spot, and rust, leads to a significant decrease in the harvest and marketable quality of P. domestica fruits. Therefore, breeding for resistance to these diseases is very important for planting highly productive European plum orchards. The objective of this study was to identify P. domestica cultivars resistant to four fungal diseases under the conditions of the foothill zone of Adygea.

   Materials and methods. The research material included 25 P. domestica cultivars from the collection orchard of Maikop Experiment Station of VIR. Resistance to fungal diseases was assessed in 2011–2022 using a conventional scale.

   Results and conclusions. Weather and climate conditions during the flowering, fruit growth and ripening periods of European plum affected the degree of damage inflicted by fungal diseases. Many years of testing resulted in identifying P. domestica cultivars with different scores of resistance to brown rot, shot hole, and rust. Ten P. domestica cultivars were characterized by group resistance to the abovementioned diseases: ‘Anna Shpet’ (k-3325), ‘Vengerka Rannyaya’ (k-3459), ‘Vengerka Italyanskaya’ (k-3444), ‘Musa Dzhaliev’ (k-26994), ‘Vengerka Vkusnaya’ (k-43323), ‘Persikovaya Michurina’ (k-30706), ‘Chernosliv Adygeyskiy’ (k-23743), ‘Chernosliv Shuntukskiy’ (k-23707), ‘Yekaterina’ (yellow) (k-3520), and ‘Vasсova’ (k-27639). They can be recommended to plum breeders for the development of P. domestica cultivars with group resistance to fungal diseases in the foothill zone of Adygea.

   Vladimir Aleksandrovich Koshkin was a prominent representative of the school of plant physiologists at the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR). He introduced his ideas on the mechanisms of photosynthesis intensity as well as the distribution of photoperiod sensitivity and the rate of development among plant species diversity. He was the first to examine in detail and disclose the relationship between the carbon dioxide compensation point and leaf temperature in C₃ and C₄ plants. According to Dr. Koshkin, there was no change in the sign of the photoperiodic reaction in the generic evolution of Triticum L. and Aegilops L., while the spring forms of bread and durum wheat widespread in the equatorial zone demonstrated weak photoperiod sensitivity. In his work with the resource departments of VIR, Dr. Koshkin was interested in plant breeding problems in the context of developing earlier-ripening cereal cultivars with a certain reaction to the photoperiod. His joint research projects with a number of breeding centers in Russia on this problem proved effective. He participated in collecting missions in Latin American countries (Cuba, Mexico, Colombia, and Brazil) and was awarded a Timiryazev Gold Medal. Dr. Koshkin was the author of 163 scientific publications and had about 20 certificates of authorship and patents for inventions, crop cultivars and lines. Dr. Vladimir Koshkin was quick to perceive the essence of any problem and used adequate modern methods to set up and analyze high-precision experiments.