Abstract: Screening and evaluating the antibacterial activity of Xinjiang's plant resources provides a foundation for the development of botanical pesticides. In this study, the antifungal activities of 13 plant extracts from Xinjiang were screened and measured through the mycelial growth rate method, targeting three wheat pathogens: Bipolaris sorokiniana, Fusarium graminearum, and Microdochium nivale. Additionally, the main components of Rumex crispus were analyzed using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The organic solvent extracts from 13 plant species showed different inhibitory activities against three wheat pathogenic fungi, and the antibacterial efficacy increased with increasing concentration. Among them, the methanol extract of Rumex crispus exhibited the strongest inhibitory activity against B. sorokiniana, with an EC₅₀ value of 6.380 mg/mL; the methanol extract of Salsola collina demonstrated the strongest inhibitory activity against F. graminearum, with an EC₅₀ value of 26.362 mg/mL; and the ethanol extract of R. crispus showed the strongest inhibitory activity against Microdochium nivale, with an EC₅₀ value of 8.203 mg/mL. A total of 42 chemical components were identified in the R. crispus extract, primarily flavonoids, fatty acyls, carboxylic acids, and their derivatives, accounting for 66.67% of the total. It can be seen from this that the methanol extract of R. crispus has good antibacterial activity and is worth further study.

Key words: plant extracts, wheat pathogenic bacteria, antibacterial activity, ultra high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS)