球形棕囊藻游离单细胞的密度与囊体形成的关系研究  

Study on the relationship between solitary cell density and colony formation of Phaeocystis globosa Scherffel

作　　者：李杰[1] 陆家昌[1] 赖俊翔[1] 张荣灿[1] Li Jie;Lu Jia-Chang;Lai Jun-Xiang;Zhang Rong-Can(Guangxi Key Laboratory of Marine Environmental Science, Guangxi Beibu Gulf Marine Research Center, Guangxi Academy of Sciences, Nanning 530007, China)

机构地区：[1]广西科学院广西北部湾海洋研究中心,广西近海海洋环境重点实验室,南宁530007

出　　处：《植物科学学报》2022年第1期84-95,共12页Plant Science Journal

基　　金：广西科技重大专项(AA17202020);广西自然科学基金(2018GXNSFAA138194,2017GXNSFAA198166)。

摘　　要：球形棕囊藻(Phaeocystis globosa Scherffel)主要以囊体形态形成赤潮,由单细胞向囊体形态的转变是赤潮爆发的关键。本研究推测囊体形成的前提是游离单细胞达到一定密度阈值,当密度低于该阈值时,囊体无法形成。基于此,本文探究了不同条件(温度、营养充气搅动、摄食压力、初始密度)下囊体形成时游离单细胞的密度。结果显示:不同培养条件下,囊体形成所需的游离单细胞密度不一致,但都达到了10^(4)cells/mL的数量级;稀释试验表明,利用f/2培养基稀释使游离单细胞的密度小于10^(4)cells/mL时,囊体不能形成,而密度大于10^(4)cells/mL的游离单细胞对照组,在24 h内便有囊体形成。总的来说,游离单细胞在高密度情况下更容易形成囊体。Phaeocystis globosa Scherffel blooms mainly develop as colonies,and thus the transition from solitary cells to colonies is key to understanding P.globosa blooms.We tested the hypothesis that a particular solitary cell density is necessary for colony formation,below which colonies will not form.We first cultured solitary cells under different conditions(e.g.,temperature,nutrients,aeration,agitation,predator pressure,and initial densities)to identify the solitary cell density at which colonies were first observed.Results showed that solitary cell density at the time of colony appearance varied with different culture conditions but was within an order of magnitude of~10^(4)cells/mL.Following the culture experiments,a dilution experiment was conducted to determine whether colonies formed when solitary cell density was diluted with f/2 media to less than 10^(4)cells/mL.Results showed that no colonies were formed.However,colonies formed within 24 h when the same inoculum was diluted with a small volume of f/2 media,which allowed the density to increase to greater than 10^(4)cells/mL.Thus,solitary cells of P.globosa are more likely to form colonies at high density.

关 键 词：球形棕囊藻 游离单细胞 密度 囊体 

分 类 号：Q945.79[生物学—植物学]