Growth competition between toxic dinoflagellate, Alexandrium, and diatom.

塔玛海链藻与海链藻、角鲨藻、星藻等硅藻的培养结果表明，塔玛海链藻与星藻的生长相互抑制。抑制程度取决于混合物种的细胞密度比例。在塔玛阿氏藻和中肋骨条藻的培养中，观察到了不同的生长模式。在这种情况下，即使当相对细胞密度显著不同时，两种物种也没有显示出对彼此的显著生长抑制。这些结果与大船渡湾浮游植物群落的演替规律相吻合，表明这种生长竞争是控制浮游植物群落组成的重要因素之一。但是，这些因子的变化与生长竞争之间没有明显的关系，表明生长抑制是由其他因素引起的。 ...更多信息 机械论另一方面，塔玛海链藻的培养基明显抑制海链藻的生长，表明塔玛海链藻细胞分泌的某些物质参与了在上述生物藻培养物中观察到的海链藻的灭绝。海链藻和Cheatocers的培养液也抑制了塔玛阿氏藻的生长，而对双链藻没有影响。这些结果表明，化感物质在塔玛阿魏玛藻与硅藻的生长竞争中起着重要作用。在自然环境中，硅藻的生物量是压倒性的相比，A. tamarense。因此，硅藻对塔玛藻的生长抑制作用似乎对控制物种组成更为重要。塔玛海链藻的化感物质为脂溶性物质。海链藻对塔玛链藻化感作用的物质也是脂溶性物质。色谱行为表明该物质是一种碳氢化合物。少

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