日本菟丝子对薇甘菊的化感作用

The allelopathic effects of Cuscuta japonica on Mikania micrantha

以薇甘菊(Mikania micrantha H.B.K.)和萝卜(Raphanus sativus L.)种子为受体,采用生物检测的方法研究了菟丝子属(Cuscuta L.)植物日本菟丝子(Cuscuta japonica Choisy)鲜茎的水浸提液及其有机萃取物的化感效应。结果表明,日本菟丝子鲜茎的水浸提液对萝卜种子的萌发表现出"低促高抑"的现象,且质量浓度越高,抑制作用越强;对薇甘菊根长的抑制作用达到了极显著水平(p<0.01),综合抑制效应指数亦达到-0.32。日本菟丝子鲜茎水浸提液的有机萃取物在折算为干茎质量浓度为10mg·mL-1(即折算为每毫升溶液曾经用10mg干茎浸泡)时就对萝卜和薇甘菊种子的萌发表现出极显著的抑制作用(p<0.01),且对两种受体的抑制趋势较一致。可见供体植物日本菟丝子具有较强的化感作用,这为利用它来控制薇甘菊的入侵提供了参考依据。

The allelopathic effects of aqueous extracts and its organic extracts of stems of Cuscuta japonica Choisy were studied using the seeds of Mikania micrantha H. B. K. and Raphanus sativus L. as receivers and by laboratory bioassay methods. The results showed that, the effect of the aqueous extracts of C. japonica stems on the germination of R. sativus appears that when the concentration of the aqueous extracts is low, there will be a stimulation to the germination, whereas, when the concentration is high, there will be an inhibition, and the higher concentration, the stronger inhibition. Moreover, the aqueous extracts of C. japonica stems exhibits extremely significant inhibition to the root growth of M. micrantha （p〈0.01）, and the synthetic inhibitory effect （SE） index reaches -0.32. The organic extracts from the aqueous extracts of C. japonica stems reveals extremely significant inhibition to the germination of seeds of M. micrantha and R. sativus at the concentration of 10 mg.mLl （p〈0.01）, and the two plant receivers show an identical trend of inhibition. Obviously, the donor plant C. japonica has strong allelopathic effects, and it is hopeful to develop the biological herbicides to inhibit the growth of M. micrantha. The paper provides a reference for the control of the invasion of M. micrantha.