o:10050 Bacillus velezensis enhances nitrogen content and stress resilience in wheat en Abstract: Bacillus species, including Bacillus velezensis, are plant growth-promoting rhizobacteria (PGPR) that enhance crop performance by improving nutrient uptake and alleviating biotic stresses. Nitrogen (N) status is crucial for wheat growth, photosynthesis, and yield, particularly under pathogen pressure. Microbial inoculants can increase N uptake and assimilation, elevate photosynthetic capacity, and mitigate stress by mechanisms such as ACC deaminase production, antimicrobial compound synthesis, and induction of systemic resistance. This study investigated the effect of B. velezensis BHC 3.1 inoculation on N content in wheat (Triticum aestivum) under infection with Fusarium poae. A pot experiment was conducted in a semi-controlled greenhouse with four wheat seed treatments: i) uninoculated control (Ø), ii) bacterial inoculation (B), iii) fungal infection (F), and iv) combined fungal infection and bacterial inoculation (B+F). Leaf nitrogen content was measured at the early heading stage using a Dualex Scientific leaf clip meter device. In comparison to the uninoculated control (Ø), fungal infection (F) decreased N content for 17.95%. On the other hand, bacterial inoculation (B) increased N content by 17.76% relative to the uninoculated control. In infected plants, inoculation (B+F) enhanced N content by 30.22% compared to infected plants without inoculation (F). These results indicate that B. velezensis reduces the negative effects of F. poae infection on nitrogen accumulation, likely through improved nutrient uptake and stress alleviation mechanisms. In this way, inoculation with this strain strengthens plant physiological resilience and nutrient status under pathogen pressure. Overall, B. velezensis BHC 3.1 has the potential for improving wheat nitrogen status and stress tolerance, highlighting its role in biotic stress conditions. Bacillus velezensis; Fusarium poae; Triticum aestivum; nitrogen status; microbial inoculants 1552100 978-86-7078-201-3 91552100 198274825 2026-07-23T08:39:08.654Z 44 no 46 Magdalena Knežević Institute of Soil Science 0000-0003-0186-3652 46 Aneta Buntić Institute of Soil Science 0000-0002-7068-1804 46 Marina Dervišević Milenković Institute of Pesticides and Environmental Protection 0000-0003-2661-6412 application/pdf 1552767 https://unilib.phaidrabg.rs/o:10050 no yes 1 70 92000004 71A05 Book of Abstracts: 1ST SOUTH-EAST TRANSNATIONAL CONGRESS OF MICROBIAL SCIENCES (SETCOMS 2026 & MIKROMED REGIO 6) “MicroFusion, Big Impact – Microbiology, Health & Environment in Harmony” June 10-13, 2026, Belgrade, Serbia 142 142 2026