3种常见茜草科药用植物化感作用的生物测定

Bioassay of allelopathic effects of three medicinal plants from rubiaceae family

以南方常见的3种茜草科药用植物鸡屎藤〔Paederia scandens(Lour.)Merr.〕、剑叶耳草(Hedyotis caudatifolia Merr.etMetcalf)、玉叶金花(Mussaenda pubescens L.)为材料,采用常规水浸提方法制备不同浓度的水提液,用生物测定法测定比较其对萝卜(Raphanus sativus L.)的化感作用,并通过测定对受体根系活力和叶片游离脯氨酸、叶绿素含量的影响,初步探讨其化感作用机理。结果表明:水提液浓度不同,其化感效应不同;供试植物不同,化感效应差别也较大,浓度较低时,化感作用较小;具体表现为,3种供试植物化感作用顺序为:鸡屎藤>剑叶耳草>玉叶金花;鸡屎藤水提液处理显著降低了受体萝卜发芽率、发芽速率指数和叶绿素含量,显著提高了受体萝卜幼苗叶片脯氨酸含量。

In the present study,the allelopathic effects of water extracts of Paederia scandens（Lour.） Merr.,Hedyotis caudatifolia Merr.et Metcalf and Mussaenda pubescens L.on Raphanus sativus L.were tested by bioassay,and the mechanism of the allelopathy was also preliminarily explored by determining root activities,free proline contents of leaves and chlorophyll contents of acceptor.Results showed that different concentration of water extracts from donors had certain allelopathy on acceptor,and the allelopathy enhanced with the increase of extracts concentration.From the results,the order of allelopathic potential of donors was P.scandensH.caudatifoliaM.pubescens.It could be concluded that the allelopathy of water extracts of P.scandens posed certain inhibitory effects on acceptor with significantly reduced germination percentage,germination rate index,and chlorophyll content of acceptor,and increased free proline content of acceptor＇s leaves.