Blue honeysuckle (Lonicera caerulea var. kamtschatica Sevast.) is a valuable berry crop with a unique biochemical composition. It is rich in vitamins, minerals, and biologically active substances. Different species and cultivars of honeysuckle require different cultivation conditions in the field of accelerated reproduction in vitro. Taking into account the high clonal replication potential of the plant, we conducted research on the chelated-iron form’s influence on the micropropagation productivity of the blue honeysuckle “Lulia” cultivar at the multiplication, rooting, and subsequent acclimatization stages of microplants. In a preliminary study, five types of iron chelates were tested with carboxyl- and phosphorus-containing ligands: Fe(III)-EDTA, Fe(III)-DTPA, Fe(III)-EDDHA, Fe(III)-HEDP, and Fe(II)-HEDP. Each type of iron chelate was applied at four concentrations: standard, decreased by 2 times, and increased by 1.5 times and 2 times in the basic Murashige and Skoog (MS) nutrient medium. It was found that the blue honeysuckle “Lulia” had a selectivity to the type of iron chelate that was used. The nutrient-medium modifications with iron chelates, which caused the plant response, contributed to a significant improvement in the plant’s physiological status and increased its survival rate during the microplant’s acclimation to the nonsterile conditions stage. At the rooting stage, an increase in the rooting rate of up to 100% (Fe (III)-EDDHA), an increase in the number of shoots by 1.5–2 times, and an increase in the number of roots by 1.4–1.9 times were observed. The positive effect of the iron’s chelated forms was also observed at the acclimation stage. According to the results of the research, the most suitable iron forms for clonal micropropagation of blue honeysuckle were carboxyl-containing Fe(III)-EDDHA and phosphonate-containing Fe(II)-HEDP. Moreover, the effectiveness of both complexonates was confirmed in a wide concentration range: Fe(III)-EDDHA from (×1.0) to (×2.0), and Fe(II)-HEDP from (×0.5) up to (×1.5).

Timeliness. Currently, the Russian Federation has a high demand in healthy planting material of garden strawberries. The benefits of using fertilizers when growing strawberry seedlings have been proven by numerous studies. However, a comparative study of the effect of new fertilizers and methods of their application is very limited. In this regard, studies aimed at identifying the effectiveness of the use of prolonged-acting fertilizers in the production of garden strawberry planting material in protected soil conditions are relevant.Methods. Adapted to non-sterile conditions, ex vitro healthy garden strawberry plants were planted in a peat substrate of Veltorf LLC (recipe No. 5c/2) with the addition of Pg mix starter fertilizer with the structure NPK 14-16-18 + microelements (1.5 g/l of substrate). At the same time, prolonged-acting fertilizers were introduced into the substrate in the recommended concentrations: FertiPro Gran 1M (1.25 g/l of substrate), Ruscote 5-6M (3.0 g/l of substrate), Basacote Plus 6M (4.0 g/l of substrate), control peat substrate without fertilizers, PG mix standard.Results. It has been established that for the Karmen crop with an average runner-forming ability, the effectiveness of applying FertiPro Gran 1M fertilizer to the substrate was revealed, with the use of which, on the 180th day of cultivation, the number of runners and rosettes increases by 3.5–3.8 times compared to the control. At the same time, the yield of marketable seedlings is 95% compared to 70% in the control. For the Jūnija smaids crop with a high vine-forming ability, the effectiveness of all experimental variants with the application of FertiPro Gran 1M, Ruscote and Basacote Plus fertilizers to the substrate was revealed, with the use of which, on the 180th day of cultivation, the number of runners and rosettes increases by 1,9-2,5 times compared to the control. At the same time, the yield of marketable seedlings is 94-96% compared to 65% in the control.Conclusion. The introduction of long–acting fertilizers FertiPro Gran, Ruscote and Basacote Plus into the peat substrate with the addition of Pg mix starter fertilizer allowed a 2.3 – 3.8-fold increase in the number of runners obtained and 1.9-3.5-fold increase in the number of sockets obtained compared to the control without fertilizers.

Relevance. The increase in global production of garden strawberry fruit is due to the high demand for the products for fresh consumption and as raw material for processing. The leading countries are: PRC, USA, Turkey, Egypt, Mexico, Spain, Russia, Poland, South Korea, Brazil. Increase in production volumes is provided due to high productivity of new varieties and intensification of strawberry cultivation technologies and, in particular, plant nutrition. The possibility of managing the nutrition of garden strawberry plants is one of the priority tasks from the solution of which depends on the realization of the potential of plant productivity, as well as the quality of the resulting products The role of many macroand microelements in plant nutrition is not fully understood. Numerous studies are conducted to identify the mechanisms of their absorption and movement in strawberry plants. New forms of fertilizers are being studied, allowing to effectively influence the processes of growth and development of plants, minimize the impact on the environment.Results. The article is devoted to the review of the role of the main mineral macroand microelements in plant nutrition, such as nitrogen, phosphorus, potassium, magnesium, calcium, iron, silicon, molybdenum. Based on the analysis of literary sources, the influence of certain mineral elements on physiological processes associated with the growth and development of garden strawberries is considered. The data on reaction of plants to the optimal content, excess and deficiency of certain elements, possibilities of their receipt and assimilation by plants of garden strawberries are given. Application in practice of the world experience on management of mineral nutrition can significantly improve the existing technologies of strawberry cultivation in open and protected ground.

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.

Relevance. The potential to enhance the stress resistance of plants in a changing climate underpins the improvement of modern agricultural technologies. Understanding the role of micro- and macroelements in the growth and development processes of plants allows for the regulation of their resilience to various stresses, among which water deficit is one of the most significant. Long-term global research has identified the stress-protective function of selenium, confirming the importance of this element in enhancing the life functions of organisms and its high effectiveness in plant survival under stress conditions. However, information regarding the effects of selenium on different plant species, the forms of selenium-containing preparations and fertilizers, and their concentrations varies. Consequently, research aimed at identifying the influence of selenium-containing preparations on the growth of plants in the Asteraceae family (Asteraceae) under conditions of water deficit is highly relevant. Methods. An experiment was conducted to study the effect of a selenium-containing preparation on the growth of common species in the Asteraceae family: Аnnual aster ( Callistephus chinensis ), Tagetes patula (Tagetes patula ), and Hybrid dahlias ( Dahlia × hortensis ) under water deficit conditions in a controlled environment. Biometric parameters were evaluated for the studied plants: stem height (cm), number of leaves (pieces), and leaf area (cm²), which affect their ornamental quality. Measurements were taken on the 7 ^th day after stress exposure. Results. Specific reactions of the studied species of Asteraceae family plants to the effect of a selenium- containing preparation under conditions of water stress were revealed. It was found that the use of the studied preparation during the drought period promotes the growth of shoots in Аnnual aster, Tagetes patula, and Hybrid dahlias plants, the preservation of existing leaves and the growth of new leaves in Аnnual aster and Hybrid dahlias plants, and the increase in leaf area in Аnnual aster plants, which generally affected the greater vitality of the plants, their faster recovery after drought, and the preservation of their decorative properties. It was noted that Tagetes patula showed the highest resistance to water stress among the studied species of the Asteraceae family. Conclusion. The use of the selenium-containing drug had a positive effect on plant growth in the studied species of the Asteraceae family ( Asteraceae ): Аnnual aster ( Callistephus chinensis ), Tagetes patula ( Tagetes patula ), and Hybrid dahlias ( Dahlia × hortensis ) in conditions of water scarcity, contributing to the preservation of vitality and decorative properties.