Evaluation of benthic foraminiferal test morphology in terms of experimental biology.

本研究旨在通过培养实验阐明底栖有孔虫测试形态的生物学意义。在精确控制水温、盐度、溶解氧含量、光照强度等环境因子的条件下进行了培养试验。(1)培养系统：从日本列岛周围许多地方采集的底栖有孔虫保存在实验室中进行培养实验。在实验室中进行三种不同的原种培养：粗培养、原始培养和克隆培养。粗养是一种以天然底质饲养多种生物的养殖方式。原始培养物是从原始培养物群体中挑选出的单一物种的原种，克隆培养物是具有相同遗传组成的克隆群体的原种。(2)控制环境培养试验：对哈代轮唇虫、贝氏氨虫、光萼甲藻、 ...更多信息 percularis。生长速率根据培养水的温度和盐度而变化。但是，试验形态未发生变化。试验形态的变化与培养水中的溶解氧含量有关。在低氧环境下，试验的顺利进行。而在高氧环境下，外周呈叶状。贝氏氨的孔径也随养殖水体中氧含量的变化而变化。A. Beccarii在低氧环境下形成大孔。这些结果表明，溶解氧含量对底栖有孔虫形态的测试有很大的影响。在控制水压和饵料含量的条件下，对采自相模湾的深海有孔虫进行了人工养殖。深海底栖有孔虫在高水压和高食物含量的环境中生长良好。(3)繁殖试验：成功地进行了盖氏光鳃藻的繁殖试验，成功地进行了质体受精配对。大量的子细胞由质体受精产生。少

This research is to clarify the biological meanings of benthic foraminiferal test morphology through culture experiments. Culture experiments were made under the condition that water temperature, salinity, dissolved oxygen contents, light intensity, and other environmental factors were precisely controlled.(1) Culture systems: Benthic foraminifera, which were collected from many places around Japanese Islands, are maintained in the laboratory for culture experiments. Three different kinds of stock cultures are running in the laboratory: rough culture, raw culture and clone culture. Rough culture is a culture which keeps many species with natural bottom substrate. Raw culture is a stock of single species which is picked up from populations of rough culture.Clone culture is a stock of cloned population having a same genetic composition.(2) Culture experiments under controlled environments: Culture experiments were made for three species, Trochammina hadai, Ammonia beccarii, Glabratella o … More percularis. Growth rates were changed according to temperature and salinity of culture water. However, test morphology is not changed. Test morphology was changed in relation to the dissolved oxygen contents in culture water. Periphery of a test is smoothed under the low oxygen environment. In contrast, periphery is lobated under the high oxygen environment. Pore diameters of Ammonia beccarii also changed with the oxygen contents in culture water. A. beccarii made large pores under the low oxygen environments. These results show that dissolved oxygen content is strongly affect to test morphology of benthic foraminifera. Deep-sea foraminifera which were collected from Sagami Bay are cultured under the conditions that both hydroaulic pressure and food contents are controlled. Deep-sea benthic foraminifera were well grown in high hydroaulic pressure and high food contents.(3) Breeding experiments: Breeding experiments of Glabratella opercularis were succeeded to make plastogamic pairs. Lots of daughter cells were born from plastogamic pairs. Less