Activity of Mikania micrantha H.B.K. allelochemicals released in soil

摘要

In laboratory and green house investigations, we studied the allelopathic effects of soil beneath the Mikania micrantha H.B.K on germination and seedling growth of tomato (Lycopersicon exculentum Mill.), cabbage (Brassica chinemis L.) and ryegrass (Lolium multiforum Lam.). In laboratory studies, the extracts of soil beneath M. micrantha decreased the shoot length of tomato, but not of cabbage and ryegrass. However in greenhouse, the soil beneath M. micrantha reduced root elongation of cabbage but stimulated the root elongation of ryegrass. Besides there was no reduction in Cabbage roots growth in the same soil supplemented with activated charcoal. The soil beneath M. micrantha and its extracts were moderately allelopathic. The M. micrantha allelochemicals released into soil did not reach phytotoxic concentrations. These results indicate that allelopathy is not the main mechanism for the invasive success of M. micrantha.