In order to achieve the optimal number of colony forming units and a high level of antifungal metabolites synthesis, we carried out the periodic cultivation of the Bacillus subtilis BZR 336 g and Bacillus subtilis BZR 517 strains at various pH and temperature levels. In the experiment for determining the optimal temperature, the maximum titer of B. subtilis BZR 336 g bacterium (1.6–1.7 × 10⁹ CFU/ml) was recorded at a cultivation temperature of 20–25 °C. For B. subtilis BZR 517 strain, the temperature turned out to be optimal at 30 °C: the titer was 8.9 × 10⁸ CFU/ml. The maximum antifungal activity of B. subtilis BZR 336 g strain against the test culture of Fusarium oxysporum var. orthoceras was observed at a cultivation temperature of 20–25 °C; for B. subtilis BZR 517 strain, 25–30 °C. When determining the optimal pH level, it was found that a high titer of B. subtilis BZR 336 g strain cells was determined at pH 8.0 (2.7 × 10⁹ CFU/ml), for B. subtilis BZR 517 strain it was at pH 6.0–8.0 (1.0 × 10⁹ CFU/ml). The maximum antifungal activity was noted with the same indicators. Chromatographic and bioautographic analyses suggest that the synthesized antifungal metabolites belong to surfactin and iturin A. The data obtained in this research can be used in the development of the technology for the production of effective biofungicides to protect crops against Fusarium pathogens.

为了获得最佳的菌落形成单位数量和高水平的抗真菌代谢产物合成，我们在不同的pH和温度水平下对枯草芽孢杆菌BZR 336 g和枯草芽孢杆菌BZR 517菌株进行了定期培养。在确定最佳温度的实验中，在 20–25°C的培养温度下记录了枯草芽孢杆菌BZR 336 g细菌的最大滴度（1.6–1.7×10 ⁹ CFU / ml）。对于枯草芽孢杆菌BZR 517菌株，温度在30°C时最适：滴度为8.9×10 ⁸  CFU / ml。枯草芽孢杆菌BZR 336 g菌株对拟南芥的测试培养物的最大抗真菌活性。尖孢镰刀菌变种 在20–25°C的培养温度下观察到直角龙；用于枯草芽孢杆菌BZR 517菌株，温度25–30°C。确定最佳pH值时，发现在pH 8.0（2.7×10 ⁹  CFU / ml）下测定了高滴度的枯草芽孢杆菌BZR 336 g菌株细胞，而在pH 6.0下测定了枯草芽孢杆菌BZR 517菌株–8.0（1.0×10 ⁹ CFU /毫升）。使用相同的指标记录了最大的抗真菌活性。色谱和生物自显影分析表明，合成的抗真菌代谢物属于表面活性素和iturinA。本研究中获得的数据可用于开发生产有效的生物杀菌剂以保护农作物免受镰刀菌病原体侵害的技术。