互花米草浸提液对中肋骨条藻的化感效应

Allelopathic effect of aqueous extract from Spartina alterniflora on Skeletonema costatum

以互花米草凋落物为化感供体材料,研究不同浓度的互花米草凋落物浸提液(0、0.02、0.04和0.10 mg·L^(-1))对中肋骨条藻生长及生理生化特征的化感效应,分离鉴定互花米草浸提液中的抑藻化感物质成分。结果表明:互花米草凋落物浸提液对中肋骨条藻生长的抑制作用随着浸提液质量浓度的增大而增强,当质量浓度为0.10 mg·L^(-1)时,互花米草凋落物浸提液对中肋骨条藻的抑制率达到69.2%;各实验处理组的中肋骨条藻细胞内的叶绿素a含量和抗氧化酶活性均低于对照组,而丙二醛的含量高于对照组;对互花米草凋落物浸提液进行抑藻化感物质的分离鉴定,其化感物质主要为长链脂肪酸,主要成分为十六烷酸、亚油酸、油酸。

We investigated the effects of aqueous extract from litter of Spartina alterniflora with different concentrations（ 0,0.02,0.04,0.10 mg·L^-1） on the growth and physiological characteristics of Skeletonema costatum. The cell concentration of S. costatum,chlorophyll-a content,antioxidant enzyme（ superoxide dismutase and peroxidase） activities and malondialdehyde content were examined. Moreover,we isolated and identified the algicidal allelochemicals from S.alterniflora. The results showed that the inhibitory effect of the extract of S. alterniflora litter on the growth of S. costatum increased with the extract concentrations. The inhibitory rate was 69.2%under 0. 10 mg·L^-1 of extract. The content of chlorophyll a and the activities of antioxidant enzyme were lower in all treatments than the control, and the content of malondialdehyde increased in all treatments. The components of allelochemicals from S. alterniflora were mainly composed of long-chain fatty acids,including hexadecanoic acid,linoleic acid,and oleic acid.