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试验形态的生物学意义。在精确控制水温、盐度、溶解氧含量、光照强度等环境因素的条件下进行培养实验。(1)培养系统：从日本列岛周围许多地方收集的底栖有孔虫在实验室中进行培养实验。实验室里有三种不同的砧木培养：粗培养、原培养和无性系培养。粗糙培养是一种以天然底基质保持多种物种的培养。原始培养物是从原始培养物群体中获得的单一物种的种群。克隆培养是指具有相同遗传组成的克隆群体。(2)可控环境下的培养实验：分别对Trochammina hadai、氨beccarii、Glabratella和More percularis进行了培养实验。根据培养水的温度和盐度变化生长速率。然而，测试形态没有改变。实验形态随培养水溶解氧含量的变化而变化。试验外围在低氧环境下被平滑。相反，外周在高氧环境下呈分叶状。贝卡氏氨菌的孔径也随培养水中氧含量的变化而变化。贝氏芽孢杆菌在低氧环境下气孔较大。这些结果表明，溶解氧含量对底栖有孔虫的测试形态有很大的影响。以相模湾深海有孔虫为研究对象，在控制水压和食物含量的条件下进行养殖。深海底栖有孔虫在高水压和高食物含量条件下生长良好。(3)育种实验：成功地进行了包皮光蝶的育种实验，获得了塑性对。许多子细胞从塑成对中诞生。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