Abstract：In this study, the chemical composition of the volatile oil from Backhousia citriodora was analyzed by gas chromatography-mass spectrometry (GC-MS), and the relative percentage content of each chemical component was determined by peak area normalization method. The nematocidal activity of the volatile oil against Bursaphelenchus xylophilus was determined, and antibacterial activities against Agrobacterium tumefaciens, Pseudomonas lachrymans, Xanthomonas vesicatoria and Bacillus subtili were also determined in sterile 96-well plates using the microculture tetrazolium (MTT) assay. A total of 35 components were identified from the volatile oil of B. citriodorae, which accounted for 87.17% of total content. The major compounds were Geranial (34.35%), Neral (29.88%) and Isogeranal (3.91%), which accounted for 68.13% of the total content. The relative contents of other components were less than 3%. The volatile oil had significant nematocidal activity against B. xylophilus, with LC50 values of 138.30 ug/mL, 107.83 ug/mL and 85.56 ug/mL at 24 h, 48 h and 72 h, respectively. The results of antibacterial activity showed the best inhibitory activity against X. vesicatoria, with IC50 value of 154. 11 ug/mL, while the LC50 values were all higher than 200 ug/mL against P. lachrymans, A. tumefaciens and B. subtilis. The volatile oil showed good inhibitory activity against B. xylophilus and X. vesicatoria. This study provides an important theoretical basis for the development and utilization of volatile oil of B. citriodora.
2023, Vol. 36 
