金鱼藻与铜绿微囊藻共生情况下的化感作用

Allelopathic effects of Ceratophyllum demersum and Microcystis aeruginosa in co-cultivation

研究了金鱼藻(Ceratophyllum demersum)和铜绿微囊藻(Microcystis aeruginosa)共生时二者之间的相互作用.通过追踪测定铜绿微囊藻的藻细胞密度、叶绿素a浓度、藻胆蛋白含量、超氧化物歧化酶(SOD)活性以及丙二醛(MDA)含量,研究了金鱼藻对铜绿微囊藻的化感作用机制,以及铜绿微囊藻对金鱼藻生长的胁迫.结果表明,金鱼藻对铜绿微囊藻有明显的抑制作用,作用96h后藻细胞完全死亡;排除营养和光的竞争影响,认为抑制作用主要是由化感作用引起的.培养过程中,铜绿微囊藻叶绿素a和藻胆蛋白(包括藻蓝蛋白、别藻蓝蛋白和藻红蛋白)都有不同程度的损伤;作用末期,藻蓝蛋白的损伤程度最大,叶绿素a次之.藻细胞SOD活性以及MDA含量均呈先升高后降低的趋势.铜绿微囊藻对金鱼藻也有一定胁迫作用,使其生长量减少,叶绿素a、类胡萝卜素含量降低.

The present work describes the co-cultivation of Microcystis aeruginosa and Ceratophyllum demersum and the mechanism of their interactions.The alga density,chlorophyll-a content, phycobiliprotein content,SOD activity and MDA content were determined to study the inhibition of M.aeruginosa by C.demersum.Results showed that the growth of M.aeruginosa was substantially inhibited by C.demersum and the alga died out by 96 h.The inhibition of M.aeruginosa was due to allelopathy rather than competition between them for light and nutrients Chlorophyll-a and phycobiliprotein（including PC,APC and PE）were damaged during the co-cultivation,especially PC.SOD activity and MDA accumulation initially increased,then decreased.Although allelopathic inhibition of M.aeruginosa on C.demersum occurred in co-cultivation,M.aeruginosa also hindered the growth of C.demersum resulting in a decrease of the content of chlorophyll-a and carotenoids.