入侵植物马缨丹不同部位的化感作用研究

马缨丹是马鞭草科中一种入侵性极强的外来植物，现正在我国中南部尤其是华南地区迅速蔓延扩散。本文采用室内生物监测法研究了马缨丹不同部位水浸液的化感效应。结果表明，马缨丹果实、茎干和叶片的水浸液均对一串红种子萌发和生长产生显著的抑制作用，种子的发芽势、萌发率下降，幼芽、幼根生长的长度缩短，芽长、根长抑制指数上升，并且随着浸提液浓度的增加其抑制效应不断增强。马缨丹不同部位水浸液对发芽势的抑制作用大小为叶片＞果实＞茎干，对萌发率、芽长、根长的抑制作用大小为果实＞叶片＞茎干。说明马缨丹具有较强的化感作用，这将有利于提高其种间竞争能力，促进入侵。

Allelopathic effects of different parts of alien invasive plant Lantana camara

Lantana camara is a highly invasive alien plant of Verbenaceae family, and now is spreading rapidly throughout the south-central of China, especially in southern China. The allelopathic effects of aqueous extracts from different parts of Lantana camara were studied by laboratory bioassay in this paper. Results showed that the aqueous extracts from fruits, stems and leaves of Lantana camara had a considerable inhibitory effect on seed germination and seedling growth of Salvia splendens. The germination energy, germination rate, bud length and root length of Salvia splendens were all reduced, but the inhibition index of bud and root growth were increased in the meantime, and the allelopathic inhibitory effects generally increased with increasing concentrations. Bioassay of aqueous extracts from different parts of Lantana camara showed that inhibitory effects on germination energy increased respectively from stem, fruit to leaf, while the inhibitory effects on germination rate, bug length and root length changed respectively from fruit＞leaf ＞stem. This indicated that Lantana camara had strong allelopathic effects, and would be beneficial to enhance its capacity of interspecific competition and to promote invasion.