We extracted Eucalyptus essential oil by steam distillation and analyzed its chemical components by GC-MS. The inhibitory effects of α-terpineol, a component in Eucalyptus essential oil, were tested in Petri dishes on the germination and growth of Amaranthus retroflexus. The allelopathic effects of α-terpineol on A. retroflexus were examined with a pot experiment by measuring germination rate and biomass. The yield of essential oil was 0.04%. Ninety-two chemical components were detected from the essential oil. In Petri dish experiment, the germination inhibitory effect under 5 μL and 7.5 μL of α-terpineol per dish reached 100%. In pot experiment, germination, aboveground fresh and dry weights of A. retroflexus were significantly affected by α-terpineol. At the concentration of 1.6 μL·cm-3, the inhibition effect was strongest, with the allelopathic response index being -0.51 for germination, -0.62 for aboveground fresh weight, and -0.44 for aboveground dry weight, and the inhibition ratio being 51%, 62% and 44%, respectively.
采用水蒸气蒸馏法提取桉树油,通过GC-MS对其成分进行分析,以其中一种化学成分α-松油醇为代表,分别采用培养皿和盆栽试验研究其对反枝苋的化感作用。结果表明: 水蒸气蒸馏法提取桉树油的产率为0.04%,经GC-MS分析,在桉树油中共检测到92种化学成分。在培养皿条件下,α-松油醇对反枝苋的发芽和生长均具有明显的抑制作用,用量达到每皿5 和7.5 μL时,抑制率均达到100%。盆栽条件下,α-松油醇处理过的土壤会显著影响反枝苋的出苗率、地上鲜重和地上干重,浓度达到1.6 μL·cm-3时,抑制作用最大,其化感响应指数分别为-0.51、-0.62和-0.44,抑制率为51%、62%和44%。.
Keywords: Amaranthus retroflexus; Eucalyptus; essential oil; α-terpineol.