Growth competition between toxic dinoflagellate, Alexandrium, and diatom.

有毒甲藻、亚历山大藻和硅藻之间的生长竞争。

基本信息

批准号：
08660257
负责人：
OGATA Takehiko
金额：
$ 1.47万
依托单位：
KITASATO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

项目摘要

Bialgal cultures between A.tamarense and diatom such as Thalassiosira, Cheatoceros, or Asterionella showed the growth inhibition to each other. Adegree of inhibition depended upon proportion of cell density of the species mixed. On the other hand, different growth pattern was observed in the bialgal culture between A.tamarense and Skeletonema costatum. In this case, both species did not show significant growth inhibition to each other even when the relative cell density is significantly different. These results well coincided with species succession pattern observed in Ofunato Bay, indicating that these growth competition is one of the important factors which control a composition of phytoplankton community.Environmental factors such as pH,light intensity and nutrient concentration were monitored during the process of bialgal culture. However, no clear relationship was observed between change of these factor and growth competition, indicating that growth inhibition is caused by other m … More echanism. On the other hand, the cultured medium of A.tamarense clearly inhibit the growth of Thalassiosira sp., showing that some substance (s) secreted from A.tamarense cells involves in extinction of Thalassiosira observed in bialgal culture described above. Growth of A.tamarense was also suppressed by the cultured medium of Thalassiosira and Cheatocers, whereas no effect was observed in the case of Skeletonema. These results suggest that allelochemic substance plays anpimportant role in growth competition between A.tamarense and diatoms. In natural environment, biomass of diatoms is overwhelming to compare that of A.tamarense. Therefore, growth inhibition by diatoms to A.tamarense seems to be more crucial for controlling a species composition. Allelochemic substance of A.tamarense to Thalassiosira was characterized as lipid soluble substance. Substance of Thalassiosira showing allelopathy effect on A.tamarnese was also lipid soluble one. Chromatographic behavior revealed that the substance is a kind of hydrocarbon. Less

A.tamarense 和硅藻（例如 Thalassiosira、Cheatoceros 或 Asterionella）之间的双藻培养显示出彼此的生长抑制，抑制程度取决于混合物种的细胞密度比例。在这种情况下，即使相对细胞密度显着不同，两个物种之间也没有表现出显着的生长抑制。与在大船渡湾观察到的物种演替模式相比较，表明这些生长竞争是控制浮游植物群落组成的重要因素之一。在双藻培养过程中对pH、光照强度和营养浓度等环境因素进行了监测。这些因素的变化与生长竞争之间没有观察到明显的关系，表明生长抑制是由其他机制引起的。另一方面，A.tamarense 的培养基明显抑制了 Thalassiosira 的生长。 sp.，表明从A.tamarense细胞分泌的一些物质涉及在上述双藻培养物中观察到的Thalassiosira的灭绝。Thalassiosira和Cheatocers的培养基也抑制了A.tamarense的生长，但没有观察到任何效果。就骨条藻而言，这些结果表明，化感物质在自然环境中塔玛藻和硅藻的生长竞争中发挥着重要作用。因此，硅藻对 A. tamarense 的生长抑制似乎对于控制 A. tamarense 对 Thalassiosira 的化感化学物质被表征为 Thalassiosira 的脂溶性物质。对A.tamarnese显示化感作用，也是脂溶性的。色谱行为表明该物质是一种烃。