权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Studies on cellular characteristics and phylogeny of chromistan algae.

铬斯坦藻的细胞特征和系统发育研究。

基本信息

批准号：
06839005
负责人：
INOUYE Isao
金额：
$ 1.28万
依托单位：
University of Tsukuba
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

项目摘要

This study was intended to understand mixotrophic activity of were surveyed for haptophytes inhabiting in polar waters. Samples from Antarctic and Greenland were examined. It was found that only three taxa, Chrysochromulina hirta, C.spinifera and Balaniger sp.were mixotrophic, and other haptophytes such as Phaeocystis, Pappomonas and Chrysochromulina parkeae were not able to uptake food particles. Because density of haptophytes was very low, polar water samples were not suitable for examination of mixotrophy. So, culture strains mostly collected and isolated from Japanese coastal waters were used. Mixotrophic uptake rate increased as density of food particles (latex beads) increased. However, it decreased at the concentration of over 10^7 particles/ml. This was interepreted as that in such high density, the aggregate of food particles formed on the haptonema surface became bigger than 5 mum which was the maximum size of food particle C.hirta could uptake. Clearance rate of C.hirta was 0.07nl/cell/min under the condition that particle density is less than 10^7 (when 0.88 mum beads were used). This is about three times higher than that of Dinobryon, the most common member of freshwater algae that is able to uptake food particles. Variations of methods in food capturing were also surveyed for Chrysochromulina species. New type of food capture was found in C.aff brevifilum, C.asteroplastida sp.nov.and C.strobilus, that is, they form tubular structure and capturing food particle and suck it. This is different from capturing method previously known in other species, C.hirta and C.spinifera, in which the haptonema is involved in the capturing process.

本研究旨在了解在极地水域被调查的感生动物的混合营养活性。研究人员检查了来自南极和格陵兰岛的样本。结果表明，只有赤藓属（Chrysochromulina hirta）、棘藓属（c.s spinifera）和Balaniger属（Balaniger sp.）是混合营养型的，而Phaeocystis、Pappomonas和Chrysochromulina parkeae属（Chrysochromulina parkeae）等其他共生植物不吸收食物颗粒。由于共生菌密度很低，极性水样不适合用于混合营养检查。因此，主要采用从日本沿海水域收集和分离的培养菌株。混合营养吸收率随着食物颗粒（乳胶珠）密度的增加而增加。当浓度超过10^7个粒子/ml时，其浓度下降。这可以解释为在这样的高密度下，在haptonema表面形成的食物颗粒的聚集体大于5 μ m，这是c.h hirta所能摄取的最大食物颗粒大小。在粒径小于10^7的条件下（0.88粒），c.h hirta的清除率为0.07nl/ cells /min。这比能吸收食物颗粒的淡水藻类中最常见的一种恐龙高出大约三倍。此外，还调查了各种食物捕获方法对黄颡鱼的影响。在短丝c.a afbrevifilum、星形塑c.a asteroplasda sp. 11和芽孢c.a strobilus中发现了一种新的食物捕获方式，即形成管状结构，捕获食物颗粒并吮吸。这与之前已知的其他物种（如C.hirta和c.s spinifera）的捕获方法不同，在其他物种中，haptonema参与捕获过程。