| 摘要: |
| 近年来渤海海域频繁暴发以抑食金球藻（Aureococcus anophagefferens）为主的褐潮对海水贝类养殖造成巨大的危害。筛选出既能强烈抑制抑食金球藻生长又可为养殖微环境中贝类提供饵料的微藻，并将其浓缩液缓释于贝类养殖的微环境中，将对降低褐潮的危害，提高养殖经济效益具有非常重要的实际应用价值。本实验以小球藻（Chlorella vulgaris）和抑食金球藻为实验材料，采用荧光定量PCR技术监测抑食金球藻的细胞密度，研究了抑食金球藻在单培养体系中的生长情况、与小球藻共培养时两种微藻生长情况的变化以及小球藻培养滤液对其生长和叶绿素荧光参数的影响。研究结果表明：（1）在单培养体系中，抑食金球藻的生长曲线可用逻辑斯谛增长模型拟合，随着起始密度的增加，环境容量（K）逐渐减小；而抑食金球藻的种群瞬间增长率（r）、进入拐点时间及稳定期细胞密度均较为接近；（2）当小球藻与抑食金球藻以不同起始密度比共同培养时，抑食金球藻的生长均受到了显著地抑制（P<0.05），且随着小球藻比例的升高抑制作用加强；（3）滤液培养实验发现，≥10mL小球藻培养滤液的加入可对抑食金球藻的生长和叶绿素荧光参数产生显著的影响（P<0.05），生长速度减缓或滞长，叶绿素荧光参数Fv/Fm、ΦPSⅡ、alpha的值降低，Ik的值增加，PSⅡ受到损害，随着滤液加入量的增加，损害程度加深，并且不可恢复。 |
| 关键词: 抑食金球藻 褐潮 小球藻 贝类养殖 相互作用 叶绿素荧光 |
| DOI：10.11693/hyhz20151000257 |
| 分类号: |
| 基金项目:国家自然科学基金青年项目，31300393号；辽宁省自然科学基金资助项目，2014020182号；天津市科技支撑重点项目，15ZCZDNC00230号；中国博士后科学基金特别资助，2015T80212号；天津市优秀科技特派员科研专项项目，15JCTPJC56000号；辽宁省海洋与渔业科研计划项目，201415号。 |
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| INTERACTION BETWEEN CHLORELLA VULGARIS AND BROWN TIDE CAUSITIVE SPECIES AUREOCOCCUS ANOPHAGEFFERENS UNDER CONTROLLED LABORATORY CONDITIONS |
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BI Xiang-Dong1,2, ZHANG Xing-Hua3, SONG Lun4, HU Shun-Xin3, TANG Xue-Xi3, YAN Ran1
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1.Department of Fisheries Sciences, Tianjin Agricultural University, Key Laboratory of Aqua-ecology and Aquaculture of Tianjin, Tianjin 300384, China;2.College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China;3.College of Marine Life Science, Ocean university of China, Qingdao 266003, China;4.Liaoning Ocean and Fisheries Science Research Institute, Dalian 116023, China
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| Abstract: |
| Brown tide broke out in recent years in the Bohai Sea, China, in which Aureococcus anophagefferens was found responsible. The brown tide severely damaged local shellfish culture. Application of bait-microalgae can strongly inhibit the proliferation of A. anophagefferens and provide food for shellfish in the microenvironment, and could mitigate the brown tide to save economic shellfish culture. We studied the interaction between Chlorella vulgaris and A. anophagefferens, and the impacts of C. vulgaris culture media filtrate on A. anophagefferens growth and on chlorophyll fluorescence under laboratory conditions, in which the number of A. anophagefferens was monitored by quantitative real-time PCR. Results show that in the mono-culture, the proliferation of A. anophagefferens followed the Logistic model, and its initial cell density affected significantly the environmental-carrying capacity (K) of algal populations; and K values decreased gradually with the increase of initial cell densities. However, A. anophagefferens of different initial cell densities were more or less similar to the instantaneous increase rate, the time at inflexion point, and algal cell density in stationary phase. In the co-culture, the growth of A. anophagefferens was inhibited significantly (P<0.05) by C. vulgaris of different algal initial cell densities, and the inhibitory effect increased strongly with the increase of C. vulgaris proportion. In the filtrate cultivation experiment, we found that C. vulgaris filtrate at ≥10mL could remarkably affect the growth and chlorophyll fluorescence of A. anophagefferens (P<0.05). More specially, it slowed down the growth and damaged PS Ⅱ (Fv/Fm, ΦPS Ⅱ, and alpha values reduced, Ik values increased). More filtrate adding deepened the damage that tended to be irreversible. |
| Key words: Aureococcus anophagefferens brown tide Chlorella vulgaris interspecies competition shellfish culture chlorophyll fluorescence |
