三裂叶蟛蜞菊挥发物对杂草的化感作用

Allelopathic potentials of volatiles from Wedelia trilobata L.

以三叶鬼针草、稗草和莲子草3种杂草为受体植物,测定三裂叶蟛蜞菊茎叶挥发物对3种杂草种子萌发时的化感作用活性。结果表明,三裂叶蟛蜞菊的茎叶在密闭系统中产生的挥发性物质对三叶鬼针草、稗草和莲子草的幼苗生长有显著抑制作用。利用水蒸气蒸馏法所得的三裂叶蟛蜞菊茎叶挥发油对稗草、三叶鬼针草和莲子草的幼苗生长也有显著抑制作用,且抑制作用随着浓度的增大而增强。实验结果表明三裂叶蟛蜞茎叶挥发物是其产生化感作用的主要途径之一。

The allelopathic potentials of volatiles of Wedelia trilobata L. were investigated to determine the role of allelopathy in successful invasion of this alien plant in South China. The results showed that volatiles released from leaves and stems of W. triIobata L. in an airproof system significantly inhibited the seedling growth of Echinochloa crusgalli （L.） Beauv., Bidens pilosa L. and Alternanthera sessiIis L. Essential oil obtained from the steam distillation of fresh leaves and stems also significantly inhibited the seedling growth of the three weeds. The denser the essential oils was the more inhibitable it becomes. The experiments showed that volatiles of W. trilobata have allelopathic potentials which can be used as an important mechanism of successful invasion of this alien species.