菹草对普通小球藻和铜绿微囊藻的化感作用

选取沉水植物菹草与浮游藻类普通小球藻、铜绿微囊藻为研究对象,在菹草共培养胁迫下测定2种藻单独存在和按1∶1混合情况下的光密度、叶绿素a(Chl-a)、最大光化学量子产量、相对电子传递速率、可溶性糖、丙二醛以及超氧化物歧化酶活性的变化。结果表明,在菹草存在的条件下,普通小球藻、铜绿微囊藻和二者混合藻的生长被快速、强烈地抑制,抑制率最大值分别为74. 38%、80. 98%和89. 63%。3个处理组的光密度值、叶绿素a、可溶性糖和超氧化物歧化酶均低于对照组,且随时间呈明显的下降趋势,说明其光合能力逐渐减弱;而丙二醛含量在0～6 d却高于对照组,表明可能发生了浮游藻类膜脂过氧化过程。

Allelopathic Effect of Potamogeton crispus on Chlorella vulgaris and Microcystis aeruginosa

One submerged macrophyte and two algae(Chlorella vulgaris and Microcystis aeruginosa)were selected to test the allelopathic effect of submerged macrophyte on algae.The changes of optical density,Chl-a,maximum photochemical quantum yield,relative electron transport rate,soluble sugar,malondialdehyde,and superoxide dismutase activity of the two individual algae and their mixture with mixing ratio of 1∶1 were measured at co-culture stress of Potamogeton crispus.The growth of Chlorella vulgaris,Microcystis aeruginosa and mixed algae was rapidly and greatly inhibited with the presence of Potamogeton crispus,the maximum inhibition rates were 74.38%,80.98%and 89.63%,respectively.The values of optical density,Chl-a,soluble sugar and superoxide dismutase of three treatment groups were lower than those in the corresponding control groups,and the profile showed a significantly downward trend with time.The results indicated that the photosynthetic capacity gradually weakened.However,malondialdehyde contents were higher than those in the corresponding control groups during the first six days,indicating the possible occurrence of membrane peroxidation of the algae.