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

关键词:  赤潮  红色赤潮藻  球形棕囊藻  化感作用  混合营养

Key words:  Red tide  Akashiwo sanguinea  Phaeocystis globosa  Allelopathy  Mixotrophic

摘要:

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其作用方式，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5×106 cells/L的混合培养条件下，起始密度为5×105、1×106、2×106、1×107 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。

Abstract:

Both Akashiwo sanguinea and Phaeocystis globosa were red tide species that cause blooms frequently in the inshore waters of China in recent years. To explore whether there is allelopathy between A. sanguinea and P. globosa and how does it work. Akashiwo sanguinea and P. globosa were co-cultured at different initial densities, and then the culture containing whole cells, cell-free filtrate, and cell fragmentation medium of A. sanguinea were added to P. globosa to analyze their effects on the growth of the latter species. The results showed that the growth of P. globosa in all experimental groups whose initial density were 5×105 cells/L, 1×106 cells/L, 2×106 cells/L, and 1×107 cells/L have been obvious inhibition (p<0.01), when they were co-culture with A. sanguinea, and the initial density of the latter one maintain 5×105 cells/L in the mixed culture; Four components of A. sanguinea culture all inhibited the growth of P. globosa. Specifically, the strongest effect was observed in the whole-cell culture, followed by the cell-free filtrate, then was the sonicated culture. On the contrary, P. globosa had no significant effect on the cell growth of A. sanguinea (p > 0.05). Akashiwo sanguinea can inhibit the growth of P. globosa, and the allelochemicals were mainly secreted outside the cells.