红色赤潮藻对球形棕囊藻的化感作用研究

Research on the Allelopathy of Akashiwo sanguinea to Phaeocystis globosa

红色赤潮藻(Akashiwo sanguinea)和球形棕囊藻(Phaeocystis globosa)都是近年来在我国近岸海域频繁引发赤潮的藻类。为了探索红色赤潮藻和球形棕囊藻之间是否存在化感作用及作用方式,本研究采用不同起始密度培养红色赤潮藻与球形棕囊藻,并将前者的完整细胞培养液、无细胞滤液、藻液超声破碎液分别与球形棕囊藻进行混合培养,分析红色赤潮藻对球形棕囊藻细胞生长的影响。结果显示,在红色赤潮藻细胞起始密度保持5×10^(5)cells/L的混合培养条件下,起始密度分别为5×10^(5)、1×10^(6)、2×10^(6)、1×10^(7)cells/L的球形棕囊藻生长均受到明显的抑制;无论是含有红色赤潮藻完整细胞的培养液,还是其无细胞滤液或藻液超声破碎液,均对球形棕囊藻的生长具有显著抑制作用(P<0.01),抑制强度由强至弱依次为完整细胞培养液、无细胞滤液和藻液超声破碎液;相反,球形棕囊藻的存在对红色赤潮藻细胞的生长无显著影响(P>0.05)。因此,红色赤潮藻具有抑制球形棕囊藻生长的化感作用,其化感物质主要分泌于细胞外。

Both Akashiwo sanguinea and Phaeocystis globosa are the algae that frequently cause red tides in China′s coastal waters in recent years.In order to explore whether there is allelopathy between A.sanguinea and P.globosa and how does it work,in this study,A.sanguinea and P.globosa were co-cultured at different initial densities,and the complete cell culture medium,cell-free filtrate and ultrasonic fragmentation medium of algae liquid of the former were mixed with P.globosa respectively to analyze the effect of A.sanguinea on the growth of P.globosa cells.The results showed that the growth of P.globosa with initial cell densities of 5×10^(5),1×10^(6),2×10^(6),and 1×10^(7) cells/L was significantly inhibited when the initial cell density of A.sanguinea was maintained at 5×10^(5) cells/L.The growth of P.globosa was significantly inhibited by either the culture medium containing intact cells of A.sanguinea,the cell-free filtrate or the ultrasonic fragmentation medium of algae liquid(P<0.01).The order of inhibition intensity from strong to weak was complete cell culture medium,cell-free filtrate and ultrasonic fragmentation medium of algae liquid.On the contrary,the presence of P.globosa had no significant effect on the cell growth of A.sanguinea(P>0.05).Therefore,A.sanguinea has the allelopathic effect of inhibiting the growth of P.globosa,and its allelochemicals are mainly secreted outside the cells.