Vasilchenko, N. | bioRxiv Science

bioRxiv2025

Systemic induced plant resistance genes expression in winter wheat under treatment with antagonistic bacteria of Fusarium sp.

IntroductionFusarium species are devastating wheat pathogens. Plant growth-promoting rhizobacteria (PGPR) offer an effective biocontrol alternative. This study investigated the capacity of a Bacillus and Paenibacillus consortium to induce systemic resistance in winter wheat. MethodsWinter wheat plants were treated with a ten-strain PGPR consortium, with or without Fusarium oxysporum and F. graminearum. Expression of five PR-gene families was quantified in roots and shoots at 7 and 14 days post-treatment via RT-qPCR. Morphometric parameters were tracked for 28 days. ResultsThe consortium elicited a potent defense response. In roots at 7 days, PR-1 and PR-6 expression surged 16-fold and 38-fold, respectively. Defense activation in shoots was delayed, peaking at 14 days. After 28 days, PGPR-treated plants exhibited an 8% increase in shoot length. DiscussionThe results confirm that the bacterial strains effectively prime the wheat immune system, modulating early defense pathways and enhancing plant growth.

molecular biology↗

bioRxiv2023

NRPS genes provide antifungal activity to new Bacillus and Paenibacillus strains and change their expression in the presence of phytopathogens in a strain-specific manner

Fusarium diseases pose a significant threat to agricultural crops. In agricultural practice, various chemical fungicides, typically triazole-based, are often used to control fusariosis. However, this practice contributes to the development of resistant strains among the pathogenic fungi. A potential alternative to chemical fungicide treatments involves utilizing biopreparations derived from natural antagonists of Fusarium. Bacillus and Paenibacillus bacteria, isolated from farmland soils have shown notable antagonistic activity against phytopathogenic Fusarium fungi. Genetic analysis via PCR has indicated the presence of nonribosomal peptide synthase genes in the isolated bacterial strains, with the absence of chitinase activity suggesting that the antifungal effect primarily stems from nonribosomal synthesized peptides. Furthermore, the expression of these genes is heightened in the presence of fungi during co-culturing, although the magnitude of this effect appears to be specific to each strain and dependent on the pathogen in question. Field trials have demonstrated the efficacy of a biocontrol preparation made from studied Bacillus and Paenibacillus strains. These results suggest promising prospects for the development of pathogen-targeted treatments.

genetics↗