Prospects for the use of various species and strains of symbiotic bacteria (Xenorhabdus sp.) in the biological protection of potatoes from diseases in the European North of Russia

Research on the development of environmentally friendly plant protection systems against fungal pathogens using symbiotic bacteria Xenorhabdus sp. – symbionts of entomopathogenic nematodes (EPN) has been a new direction in agricultural practice in recent years and undoubtedly represent relevance and scientific significance. The studies used suspensions of live and autoclaved cultures of symbiotic bacteria of symbionts of various types of EPN (Steinernema carpocapsae, S. feltiae and S. feltiae protense) with a bacterial cell titer of 10⁷ CFU/ml in comparison with the biological preparation Phytosporin-M (dough) and water as a control. In laboratory conditions at a temperature of 25 ^oC, there were established differences in the antibiotic activity of the primary forms of producers of Xenorhabdus sp., isolated from different types of EPN. The greatest inhibition of the fungal growth zone on the 4th day was observed for metabolites of the S. carpocapsae strain against Alternaria solani. Biological effectiveness in suppressing this pathogen was 51 %. Field research conducted in 2022-2023 in the conditions of the Republic of Karelia on the mid-early potato variety ʻRed Scarlettʼ, showed that under epiphytotic conditions (low air temperatures and excessive waterlogging) double spraying of vegetative plants with a suspension of live and autoclaved cultures of symbiotic bacteria (EPN-1-1, EPN-2 and EPN-2 -1) reduced the development of rhizoctoniosis compared to the control variant by 50, 64 and 60 %, respectively. It was found that double treatment with a live and autoclaved aqueous suspension of bacteria, symbionts of the subspecies S. feltiae was more effective and ensured a reduction in the degree of development of scab symptoms by 1.3–2.8 times and the spread of rhizoctonia by 1.5–2.0 times. It has been also established that 2-fold spraying of plants with a live and autoclaved suspension of symbiotic bacteria S. feltiae during the growing season significantly increases the yield of tubers by 35–22 %, respectively. Thus, the use of biologically active secondary metabolites of Xenorhabdus sp. has significant potential as biological plant protection agents against potato pathogens.

1. Shapiro-Ilan D., Hazir S., Glazer I. Advances in use of entomopathogenic nematodes in integrated pest management. In: Kogan M., Heinrichs E. A. (eds). Integrated management of insect pests: current and future developments. Burleigh Dodds Science Publication. UK, 2020. pp. 1–30. DOI: https://doi.org/10.19103/AS.2019.0047.19

2. Gawad M. A., Ruan W., Hammam M. M. A. Entomopathogenic Nematodes: Integrated Pest Management and New Vistas. Egyptian Journal of Agronematology. 2023;22(1):1–18. DOI: https://doi.org/10.21608/ejaj.2023.280551

3. Pavlyushin V. A., Novikova I. I., Boykova I. V. Microbiological control in phytosanitary optimization technologies for agroecosystems: research and practice (review). Sel'skokhozyaystvennaya biologiya = Agricultural Biology. 2020;55(3):421–438. (In Russ.). DOI: https://doi.org/10.15389/agrobiology.2020.3.421rus

4. Wright P. J. Morphological characterisation of the entomogenous nematodes Steinernema spp. and Heterorhabditis spp. (Nematoda: Rhabditida). New Zealand Journal of Zoology. 1990;17(4):577–585. DOI: https://doi.org/10.1080/03014223.1990.10422955

5. Boemare N., Biology, Taxonomy and Systematics of Photorhabdus and Xenorhabdus. In: Gaugler R. (ed.). In book: Entomopathogenic nematology. CABI Publishing, CAB International, 2002. pp. 35–56. DOI: https://doi.org/10.1079/9780851995670.0035

6. Danilov L. G., Pavlyushin V. A. Development and implementation of an innovative project on the establishment of experimental production of biological preparations based on entomopathogenic nematodes. Vestnik zashchity rasteniy = Plant Protection News. 2019;(2(100)):52–55. (In Russ.). URL: https://www.elibrary.ru/item.asp?id=39132362

7. Brivio M. F., Mastore M. Nematobacterial Complexes and Insect Hosts: Different Weapons for the Same War. Insects. 2018;9(3):117. DOI: https://doi.org/10.3390/insects9030117

8. Bisch G., Ogier J. C., Médigue C., Rouy Z., Vincent S., Tailliez P., Givaudan A., Gaudriault S. Comparative genomics between two Xenorhabdus bovienii strains highlights differential evolutionary scenarios within an entomopathogenic bacterial species. Genome Biology and Evolution. 2016; 8(1):148–160. DOI: https://doi.org/10.1093/gbe/evv248

9. Murfin K. E., Whooley A. C., Klassen J. L., Blair H. G. Comparison of Xenorhabdus bovienii bacterial strain genomes reveals diversity in symbiotic functions. BMC Genomics. 2015;16:889. DOI: https://doi.org/10.1186/s12864-015-2000-8

10. Ivanova T. S., Ivakhnenko O. A., Danilov L. G. A new entomopathogenic nematode Steinernema feltiae protense subsp. N. (Nematoda: Steinernematidae) from Yakutia. Parazitologiya. 2001;35(4):333–337. (In Russ.). URL: https://www.elibrary.ru/item.asp?id=26019417

11. Boszormenyi E., Ersek T., Fodor A., Fodor A. M., Foldes L. S., Hevesi M., Hogan J. S., Katona Z., Klein M. G., Kormany A., Pekar S., Szentirmai A., Sztaricskai F., Taylor R. A. J. Isolation and activity of Xenorhabdus antimicrobial compounds against the plant pathogens Erwinia amylovora and Phytophthora nicotianae. Journal of Applied Microbiology. 2009;107(3):746–759. DOI: https://doi.org/10.1111/j.1365-2672.2009.04249.x

12. Akhurst R. J. Morphological and Functional Dimorphism in Xenorhabdus spp., Bacteria Symbiotically Associated with the Insect Pathogenic Nematodes Neoaplectana and Heterorhabditis Free. Journal of General Microbiology. 1980;121(2):303–309. DOI: https://doi.org/10.1099/00221287-121-2-303

13. Danilov L. G., Zorina E. A., Nashchekina T. Yu. Antibiotic activity of Xenorhabdus sp. (Enterobacteriaceae) symbiont of entomopathogenic nematodes (Rhabditida: Steinernematidae). Vestnik zashchity rasteniy = Plant Protection News. 2017;3(93):33–38. (In Russ.). URL: https://www.elibrary.ru/item.asp?id=30079319

14. Agansonova N. E. Effectiveness of the products of metabolism of symbiotic bacteria p. Xenorhabdus against the common scab. Zashchita i karantin rasteniy. 2016;(10):25–27. (In Russ.). URL: https://www.elibrary.ru/item.asp?id=26738475

15. Benitez T., Rincon A. M., Limon M. C., Codon A. C. Biocontrol mechanisms of Trichoderma strains. International Microbiology. 2005;7(4):249–260. URL: https://www.researchgate.net/publication/8065870_Biocontrol_mechanism_of_Trichoderma_strains

16. Fang X. L., Li Z. Z., Wang Y. H., Zhang X. In vitro and in vivo antimicrobial activity of Xenorhabdus bovienii YL002 against Phytophthora capsici and Botrytis cinerea. Journal of Applied Microbiology. 2011;111(1):145–154. DOI: https://doi.org/10.1111/j.1365-2672.2011.05033.x