加拿大一枝黄花化感抑藻效应的初步研究

利用植物化感作用,可抑制有害藻类的生长,改善富营养化水体水质。文章选择我国重要的陆生入侵植物加拿大一枝黄花（Solidago canadensis L.）,系统研究了其根部、茎部和叶部水浸液对5种常见藻类：铜绿微囊藻（Microcystis aeruginosa）、斜生栅藻（Scenedesmus obliquu）、蛋白核小球藻（Chlorella pyrenoidosa）、水华鱼腥藻（Anabaena flos-aguae）和羊角月牙藻（Selenastrum capricornutum）生长的化感效应。研究结果表明：（1）加拿大一枝黄花水浸液对铜绿微囊藻的生长有强烈的化感抑制效应,7 d抑制率为90%左右,根、茎、叶部水浸液的72 h-EC50由高到低依次为34.84、12.54和9.57 g.L^-1,叶部对铜绿微囊藻的抑制作用最强;（2）加拿大一枝黄花叶部水浸液除了对水华鱼腥藻的生长无显著影响外,对其余4种受试藻均有明显的抑制作用,即加拿大一枝黄花叶部的化感抑藻效应较具广谱性;（3）相同质量浓度、同一部位的加拿大一枝黄花水浸液对不同藻种的化感作用类型和作用强度有所不同,即化感抑藻效应存在选择性,且这种选择性与藻类的分类学特征无关;（4）对同一种藻,加拿大一枝黄花根、茎、叶等不同部位水浸液的化感效应也有所差异。

Studies on the allelopathic effects of Solidago canadensis L. on algae

Some plants may inhibit the growth of harmful algae and improve water quality by releasing chemicals into environment.The allelopathic effects of extracts of different parts（root、stalk、leaf） from Solidago canadensis L.on five common algae（Microcystis aeruginosa、Anabaena flos-aguae、Scenedesmus obliquu、Chlorella pyrenoidosa、Selenastrum capricornutum） were investigated.The research results indicated that：（1） Solidago canadensis L.strongly inhibited the growth of Microcystis aeruginos in some concentration ranges,where calculated 72h-EC50 for root、stalk and leaf was 34.84 g.L^-1、12.54 g.L^-1 and 9.57 g.L^-1 respectively.The leaf extract of Solidago canadensis L.has the strongest inhibition effect compared to root and stalk extracts.（2） The leaf extract inhibited the growth of Microcystis aeruginosa、Scenedesmus obliquu、Chlorella pyrenoidosa and Selenastrum capricornutum,however not Anabaena flos-aguae,which suggested that the leaf extract has a wider allelopathic effect.（3） Under the same treatment,the allelopathic effects of Solidago canadensis L.on different algae were different,indicating a selective control of allelopathic effects.In addition,this kind of selective control was irrelevant to the taxonomic character.（4） The allelopathic effects of different parts from Solidago Canadensis L.on the same algae were also different.