Abstract Temporal changes of algicidal and growth-inhibiting bacteria on the fish-killing raphidophyte flagellate, Chattonella antiqua, at an eelgrass (Zostera marina) bed in southern Ariake Sea, Japan in 2011 was investigated. The maximum value (5.1 × 107 CFU g−1 wet leaf) of algicidal bacteria (AB) was detected from a biofilm formed on Z. marina on August 1 when AB in the adjacent seawater had also peaked (1.2 × 104 CFU mL−1). Two causative bacteria isolated from the biofilm and seawater on August 1 were both identified to be of the genus Alteromonas (γ-proteobacteria). AB and growth-inhibiting bacteria (GIB) were present from the beginning of sampling (May 20) to August 26, fluctuating between 8.6 × 102 and 1.2 × 104, 1.2 × 103 and 9.3 × 103 CFU mL−1, respectively. The highest phytoplankton density observed was 6423 cells mL−1 on September 29 and was comprised of centric diatoms such as Chaetoceros, Skeletonema, and Thalassiosira and coincided with the absence of AB and GIB where the decline of Z. marina was also observed. These findings provide a new ecological insight on AB and GIB associated with Z. marina beds, indicating eelgrass beds have the important role as the nursery of those bacteria that can be utilized as mitigation measures of harmful algal blooms (HABs) in the future.

中文翻译：

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日本有明海鳗草床中藻类和生长抑制细菌的时间变异性

摘要 研究了 2011 年日本有明海南部鳗草（Zostera marina）床中杀鱼鞭毛藻 Chattonella antiqua 的杀藻抑菌细菌随时间的变化。8 月 1 日，当邻近海水中的 AB 达到峰值（1.2 × 104 CFU mL-1）时，在 Z. marina 上形成的生物膜中检测到了溶藻细菌（AB）的最大值（5.1 × 107 CFU g-1 湿叶）。 ）。8 月 1 日从生物膜和海水中分离出的两种致病细菌均被鉴定为交替单胞菌属（γ-变形菌）。从采样开始（5 月 20 日）到 8 月 26 日，AB 和生长抑制细菌（GIB）都存在，分别在 8.6 × 102 和 1.2 × 104、1.2 × 103 和 9.3 × 103 CFU mL-1 之间波动。9 月 29 日观察到的最高浮游植物密度为 6423 个细胞 mL-1，由中心硅藻如角角藻、骨架和海洋藻组成，同时也观察到 AB 和 GIB 的缺失，同时也观察到 Z. marina 的下降。这些发现为与 Z. marina 床相关的 AB 和 GIB 提供了新的生态学见解，表明鳗草床作为这些细菌的苗圃具有重要作用，可用作未来有害藻华 (HAB) 的缓解措施。