盐度对化感物质青蒿素胁迫下铜绿微囊藻生长及叶绿素荧光的影响

化感物质青蒿素已被证明具有良好的控制蓝藻水华的作用。为探究盐度存在情况下,青蒿素对铜绿微囊藻的胁迫作用是否受到影响,在0～15‰盐度条件下,测定青蒿素对铜绿微囊藻生长、叶绿素a含量以及叶绿素荧光参数的影响。结果表明：铜绿微囊藻具有一定的适盐性,5‰的盐度可以促进铜绿微囊藻生长,但盐度>10‰则对藻产生显著抑制作用。加入化感物质青蒿素后,低盐度对藻的促进作用消失,盐度强化了青蒿素对铜绿微囊藻的抑制和对光合系统的破坏,具体体现在破坏铜绿微囊藻光合色素、光合作用结构,降低光合反应中心的活性,降低PSⅡ受体侧的电子传递能力等方面。研究成果中为青蒿素在微咸水中的应用提供参考。

EFFECTS OF SALINITY ON GROWTH AND CHLOROPHYLL FLUORESCENCE OF MICROCYSTIS AERUGINOSA UNDER ARTEMISININ STRESS

The allelopathic substance artemisinin has been proven to be effective in controlling cyanobacterial blooms. In order to explore whether the stress of artemisinin on Microcystis aeruginosa is affected by salinity, we studied the effects of artemisinin on the growth, chlorophyll-a content, and chlorophyll fluorescence parameters of Microcystis aeruginosa under different salinity conditions (0~15‰). The results showed that Microcystis aeruginosa had a certain salinity adaptability. Salinity of 5‰ could promote the growth, but the salinity above 10‰ had a significant inhibitory effect on the growth of Microcystis aeruginosa. After the addition of artemisinin, the promoting effect of low salinity on algae disappeared, the salinity strengthened the inhibition of artemisinin on Microcystis aeruginosa and the damage to the photosynthetic system, which was reflected in the destruction of photosynthetic pigments and photosynthetic structure, the reduction of photosynthetic reaction center activity, and the decreasing of electron transport capacity of PSⅡ receptor side. The research results could provide reference for the application of artemisinin in brackish water.