The efÏciency garden strawberry production depends on the quality of planting material from mother plantations. One promising method for greening agriculture is the use of biostimulants based on seaweed extracts, which can increase the quantity and quality of daughter rosettes. The aim of this study was to evaluate the effect of the concentration and frequency of seaweed extract treatments on the reproductive performance of garden strawberry mother plants grown outdoors in southeastern Kamchatka. This article presents the results of three years of field research (2019, 2020, and 2021) examining the effect of foliar treatments with aqueous extracts of the brown algae Hedophyllum bongardianum and Alaria esculenta on the productivity of garden strawberry (Fragaria × ananassa Duch.) mother plants in southeastern Kamchatka. Research has proven that the type of algae, the concentration of the working solution and the frequency of treatments have a significant impact on growth and reproductive performance. The highest efÏciency was found when using a 10% concentration of A. esculenta extract. A single treatment with this extract significantly increased the number of rosettes by 55.2%, the number of leaves by 32.6%, the root collar thickness by 41.2% and the length of the roots by 13.1% compared with the control. At the same time, the application of H. bongardianum extract, especially in high concentrations (25%) and with double treatment, in some cases led to inhibition of rosette development. The study results demonstrate the potential of using A. esculenta extract as an effective biostimulant for increasing the productivity of garden strawberry mother plantings.

Dakhno Olga A., Klochkova Nina G., Dakhno Timofey G.

1. Bruno M., Giampieri F., Zhang Y., Zhong C. Status of strawberry breeding programs and cultivation systems in Europe and the rest of the world. Journal of Berry Research, 2018;8;3:205–221. https://doi.org/10.3233/JBR-180314.
2. Gorelikova O. A. Economic efÏciency of growing intensive garden strawberry varieties in the Krasnodar krai. Subtropicheskoe i dekorativnoe sadovodstvo, 2019;71:245–250. https://doi.org/10.31360/2225-3068-2019-71-245-250 (in Russ.).
3. Zubkova M. I., Khrykina T. A., Panfilova O. V. Evaluation of the whisker-forming capacity of promising varieties of garden strawberries from mother plantings. Sovremennoe sadovodstvo, 2018;1(25):50–54. https://doi.org/10.24411/2312-6701-2018-10108. EDN LBJRPV (in Russ.).
4. Makarova K. S., Petrov A. F., Semenyuk Yu. A. Improvement of technology for production of garden strawberries in the forest-steppe conditions of Western Siberia. Vestnik Novosibirskogo gosudarstvennogo agrarnogo universiteta, 2025;1:40–46. https://doi.org/10.31677/2072-6724-2025-74-1-40-46. EDN CZAUJR (in Russ.).
5. Shibaeva T. G., Sherudilo E. G., Titov A. F. Seaweed extracts as plant biostimulants. Trudy Karel'skogo nauchnogo tsentra RAN, 2021;3:36–67. http://dx.doi.org/10.17076/eb1383. EDN ADUAJF (in Russ.).
6. Ali O., Ramsubhag A., Jayaraman J. Biostimulant properties of seaweed extracts in plants: Implications towards sustainable crop production. Plants, 2021;10;3:531. https://doi.org/10.3390/plants10030531.
7. Rabhi M. L., Derbak L., Bendif H., Boufahja F., Abu-Elsaoud A. M., Garzoli S. Seaweedderived biostimulants for sustainable crop production: A review. Journal of Biotechnology, 2025;408:201–216. https://doi.org/10.1016/j.jbiotec.2025.09.013.
8. Rengasamy K. R., Mahomoodally M. F., Aumeeruddy M. Z., Zengin G., Xiao J., Kim D. Bioactive compounds in seaweeds: An overview of their biological properties and safety. Food and Chemical Toxicology, 2020;135:111013. https://doi.org/10.1016/j.fct.2019.111013.
9. Deolu-Ajayi A. O.,van der Meer I. M., van der Werf A., Karlova R. The hower of seaweeds as plant biostimulants to boost crop production under abiotic stress. Plant Cell Environ, 2022;45:2537–2553. https://doi.org/10.1111/pce.14391.
10. Ertani A., Francisco O., Tinti A., Schiavon M., Pizzeghello D., Nardi S. Evaluation of seaweed extracts from Laminaria and Ascophyllum nodosum spp. as biostimulants in Zea mays L. using a combination of chemical, biochemical and morphological approaches. Frontiers in Plant Science, 2018;9:428. https://doi.org/10.3389/fpls.2018.00428.
11. Shukla P. S., Mantin E. G., Adil M., Bajpai S., Critchley A. T., Prithiviraj B. Ascophyllum nodosum – based biostimulants: Sustainable applications in agriculture for the stimulation of plant growth, stress tolerance, and disease management. Frontiers in Plant Science, 2019;10:655. https://doi.org/10.3389/fpls.2019.00655.
12. Program and methodology for variety testing of fruit, berry, and nut crops, Orel, Vserossiiskii nauchno-issledovatel'skii institut selektsii plodovykh kul'tur, 1999, 606 p. (in Russ.).
13. Program and methodological guidelines for agronomic experiments with fruit and berry crops, Michurinsk, 1972, 184 p. (in Russ.).
14. Stirk W. A., Van Staden J. Plant growth regulators in seaweeds: occurrence, regulation and functions. Advances in Botanical Research, 2014;71:125–159. https://doi.org/10.1016/B978-0-12-408062-1.00005-6.