Exploring the potential of new Bacillus subtilis strain VKM B-3516D against common wheat diseases for sustainable farming system

The present study evaluated the efficacy of a novel strain of Bacillus subtilis Krd-20 (VKM B-3516D) (Ehrenberg 1835) Cohn 1872 in controlling common wheat diseases. The strain was isolated in 2020 from the surface soil layer of the wheat rhizosphere in the Krasnodar region of Russia and identified at the species level based on 16S rRNA gene sequencing. Mass spectrometric analysis, PCR with primers specific to the FenD, ItuD, and SrfC synthetase genes, as well as draft genome annotation using PGAP, revealed that the strain’s fungistatic activity is mediated by the production of lipopeptides—fengycin and surfactin. Furthermore, an experimental biofungicide formulation based on B. subtilis Krd-20 (VKM B-3516D), developed as a wettable powder, was tested in vivo for its efficacy in controlling fusarium head blight (FHB) and yellow leaf spot in wheat. Field trials demonstrated a biological efficacy of 75–83% for the biofungicide. Additionally, an assessment of its compatibility with the mineral fertilizer 18:18:18 “Universal” indicated minimal impact of mineral components on microbial viability, suggesting its potential integration into combined formulations. Mycological analysis of soil demonstrated that application of the biofungicide increased disease-suppressive properties in the rhizosphere by 21.1%. Evaluation of grain infestation revealed the lowest disease incidence in treatments combining the biofungicide with fertilizer. Furthermore, the application of the biofungicide resulted in a 2.5% increase in crop yield. These findings indicate that B. subtilis Krd-20 (VKM B-3516D) has significant potential as a biofungicide within wheat production systems, contributing to sustainable agriculture. © © 2025 Kopiltsov, Astapchuk, Elisyutikova, Nazarenko, Kavhiza, Kucher, Utkina and Rebouh.