Relevance. The creation of a fund of linear material for hybrid breeding of canteen beets based on CMS with a complex of economically significant features, including resistance to highly pathogenic Fusarium species, is an urgent task today. Goal. Identification of the current composition of economically significant causative agents of fusarium rot in beetroot and a phenotypic assessment of the resistance of a promising linear material to highly aggressive Fusarium isolates.Materials and Methods. Objects of research: 71 isolates of Fusarium fungi isolated over the period 2018-2024 from affected seeds (29 isolates), leaves (10 isolates) and root crops (32 isolates) of table beet; 20 breeding lines and five hybrid combinations of beetroot. Phytopathological and molecular genetic methods were used in the work. Artificial infection of root crops was carried out with mycelial blocks of ten-day cultures of identified Fusarium species. Results. According to the results of the pathogenicity test for beet roots, it was shown that 45% of the isolates isolated into the pure culture were characterized by moderate aggressiveness. Highly aggressive isolates (23% of the number studied) were isolated from the affected head of the root crop, from the leaf vein, root and cotyledon leaves of seedlings. Molecular phylogeny using the TEF-1a and RPB2 genes, combined with morphological characteristics, showed that six Fusarium species participated in the pathogenesis of fusarium rot in beetroot during the years of research in the Moscow region: F. acuminatum, F. avenaceum, F. campestre (FTSC); F. solani (FSSC), F. flagelliforme (FIESC) and F. sporotrichioides (FSAMSC). Among them, the dominant species were F. acuminatum (with the largest proportion of highly aggressive strains) and F. avenaceum. As a result of an immunological assessment of the resistance of linear beetroot material to the highly aggressive F. acuminatum strain (F-cb-38) in vitro , three maternal lines "A" 413, 363 and 404 (Va=82, 85 and 93 mm[3] , respectively) were characterized by the smallest volume of the disc lesion zone; two paternal lines "C" 427 and 426 (Va=20 and 33 mm[3] , respectively). The lines selected for resistance to fusarium in case of artificial infection were characterized by high preservation and during storage on a natural background for five years, and were also distinguished by other economically valuable characteristics, which is important for hybrid beet breeding.
Relevance. Improving the efficiency of the pepper breeding process for resistance to fusarium wilt, caused by Fusarium verticillioides , requires studying the biological characteristics of the pathogen and the conditions for pathogenesis development according to the concept of the classical disease triangle. Taking these relationships into account is essential for developing reproducible and informative methods for evaluating breeding material. Purpose. To study the effect of temperature regime and nutrient medium composition on the vegetative growth of F. verticillioides , as well as to optimize key elements of the artificial inoculation protocol for accelerated evaluation of resistance in pepper breeding lines. Materials and methods. The study examined three F. verticillioides isolates with contrasting aggressiveness. The radial growth rate was assessed in vitro on PDA, OA, Czapek, and SNA media in the temperature range of 10-40 °C. Pathogenicity was tested in vivo on seedlings of five pepper lines at 25, 28, and 30°C. Additionally, two inoculation methods were compared: with mechanical stirring (orbital shaker, 100 rpm) and under static conditions. Results. Within the F. verticillioide s population, contrasting classes of pathogenicity were identified: highly aggressive (HA, 46%), moderately aggressive (MA, 27%), and weakly aggressive (WA, 27%). A direct correlation was established between the radial growth rate (VR) and aggressiveness: HA isolates grew 1,7-1,9 times faster than WA isolates (VR 13,0 vs. 7,6 mm/day). The temperature optimum for the growth of the highly aggressive isolate in vitro (VR 12,8 mm/day) and pathogenesis in vivo (I=3,4 points) coincided and was 28 °C. However, at 30°C, despite maintaining high growth in vitro (VR 10,3-11,8 mm/day), pathogenesis in vivo significantly decreased to 1,9 points. Two-way ANOVA showed that on day 7, the inoculation method (with shaker) accounted for 31,6% of the variance, while by day 14, the genotype dominated (40,6%). The use of an orbital shaker allowed accelerating pathogenesis and symptom manifestation, reducing the period of reliable evaluation from 14 to 7 days, which provided the opportunity for accelerated screening.Conclusion. Integration of knowledge about the biological characteristics of the pathogen into the experimental methodology allowed improving the elements of the artificial infection protocol. The use of these elements made it possible to significantly reduce screening time and increase the reliability of evaluating pepper resistance to fusarium wilt, which is important for accelerating the breeding process.
Relevance. The study is devoted to developing a scheme for the detection and identification of the bacterium Ralstonia solanacearum the causal agent of potato brown rot, which belongs to the Ralstonia solanacearum species complex ( R. solanacearum , R. pseudosolanacearum , R. syzygii ). This pathogen affects over 200 plant species, including economically important crops (potato, tomato, pepper, eggplant), and is listed as a quarantine organism absent from the territory of the Russian Federation. Objective: to create and test a laboratory diagnostic scheme for R. solanacearum for phytosanitary control of regulated products. Material and ". Methods used in the study: sample preparation method (extraction in phosphate-buffered saline with centrifugation), PCR analysis (real-time PCR using primers RS-IF/RS-II-R/RS-P and a commercial kit; PCR with electrophoretic detection using primers RS-1F/RS-1-R (RS-3-R)). Results. An optimized scheme for the identification and detection of the brown rot pathogen was developed. The scheme was tested on 242 samples of regulated products (potato, roses, peonies, bananas) submitted to the diagnostic laboratory in 2025. The results showed the absence of R. solanacearum complex bacteria in samples from the Russian Federation and revealed 14 cases of potato tuber infection in imported batches. Identification of positive samples using species-specific primers RS-1-F/RS-1-R confirmed the presence of R. solanacearum (sensu stricto).Conclusion. No false-positive or false-negative reactions were recorded during the testing of all used assays within the framework of the developed scheme, indicating their 100% specificity within the study. The outcome of the work is the creation of a reliable laboratory testing algorithm that ensures rapid and accurate diagnosis of the quarantine phytopathogen, thereby guaranteeing phytosanitary safety and compliance of products with importer requirements. plant quarantine, phytopathogenic bacteria, molecular genetic identification methods, detection, identification
Relevance. The technological qualities of the root crops in the sugar beet parent components affect the hybrids properties obtained from them. In this regard, a comprehensive analysis of the technological indicators of the parent forms and hybrid combinations in breeding studies is necessary. In addition to the sugar content, which determines the raw materials quality during processing at sugar beet factories, the content of alkaline sodium, potassium, and alphaamine nitrogen ions is traditionally studied. These ions collectively reflect the total content of molasses-forming non-sugars in sugar beets, as the concentration of these elements affects the loss of sugar in molasses and the yield of sugar during the processing of root crops.Material and methods. The work was carried out at the All-Russian Research Institute of Sugar Beet and Sugar named after A.L. Mazlumov in 2022-2023. The object of research was the roots of 25 breeding samples of sugar beet (selected by the All-Russian Research Institute of Sugar Beet and Sugar named after A.L. Mazlumov, in four repetitions – 100 samples) in comparison with the foreign hybrid Mitika (Lion Seeds LTD). The study included field experiments and laboratory analysis. To assess the technological indicators of the root crops of the studied breeding material, an express method was used in the laboratory of analytical assessment of the technological quality of sugar beet. This method involves the production of digests using the automated Venema line and the determination of sugar content, potassium, sodium, and α-amine nitrogen using the automated Betalyser sugar beet analysis line.Results. From the total number of the studied breeding samples, the best ones were selected in terms of technological qualities, which have low sugar losses in molasses (1.40-1.67%), high values of sugar yield (12.76-13.85%), its extraction coefficient during processing (82.6985.11%), and sugar content (15.43-16.32%). The content of non-sugars in the studied samples was at the standard level or below it.Conclusion. The obtained results allow to use the selected numbers in further breeding work. It is recommended to check the cross-fertile pollinators for their combinational ability.
Relevance. The red raspberry ( Rubus idaeus L.) is currently one of the most popular berry crops grown on an industrial scale. Therefore, it is necessary to continually improve techniques for its accelerated vegetative propagation. In this regard, clonal micropropagation technology has become widely used, as it enables the production of genetically uniform planting material for establishing high-quality mother stock plantations. However, the low survival of plants during the adaptation phase to non-sterile conditions remains a limiting factor in the accelerated production of planting material.Methods. The experiments were carried in 2024-2025 at the Federal State Budgetary Scientific Institution the All-Russian Research Scientific Institute of Phytopathology (ARRIP), in the Laboratory for Recovery and Research on the Adaptive Potential of Cultures and Plants, and at the Russian State Agrarian University, Moscow Timiryazev Agricultural Academy, in the Department of Biotechnology and Berry Crops of the Edelstein Educational Scientific and Production Center for Horticulture and Vegetable Growing. The study was focused on ex vitro red raspberry ( Rubus idaeus L.) microplants of the Gusar and Poklon Kazakovu varieties. After 40 days of subculture during the rhizogenesis stage, the microplants were transplanted to the adaptation stage under non-sterile conditions. High-moor peat of the ‘Seliger-Agro’ brand was used as the substrate, mixed with agroperlite in a 3:1 ratio. Planting was carried out in plastic trays (49 cells, 4×4 cm, size 40×40×7 cm). The following vermiculture products were studied in the experiments: Vermiwash Vermiaktiv by ‘NPO Zhivaya Vselennaya’ LLC, Vermitea under the Iz Kopanevki brand, and Biohumus Bio-Kompleks by ‘Bio-Kompleks’ LLC; the control was water. Results. To adaptation floricane-bearing red raspberry microplants of the Gusar variety, it is effective to prepare the microplants using a combination of Biohumus (soak in a 1:20 solution, then drench the substrate in a 1:15 solution); water the substrate with Vermitea (1:50); soak the microplants in Vermiwash (1:20). For primocane-bearing red raspberry microplants of the Poklon Kazakovu variety, soak the microplants in Vermitea (1:50) or water the substrate with Vermitea (1:50) or Biohumus (1:15) vermicompost products. By the 3 ~~0~~ [th] day of adaptation, the survival is 100%, as is the proportion of plants that meet the standards set out in GOST R 540512025 90-100%, and the morphometric indicators of development of the experimental ex vitro plants are 1.3-2.9 times higher than those of the control. Conclusion. This information could help to develop methods of accelerating the production of red raspberry planting materials. As there are currently no guidelines for using vermicompost products on different crops, more research in this area is needed.
