洱海的浮游蓝藻布氏常丝藻及其分类学的讨论  

OCCURRENCE OF PLANKTONIC CYANOBACTERIUM TYCHONEMA BOUURRELLYI IN ERHAI LAKE AND ITS TAXONOMIC STUDIES

作　　者：卫志宏[1] 朱梦灵[2] 虞功亮[2] 李仁辉[2] 

机构地区：[1]中国大理洱海湖泊研究中心,大理671000 [2]中国科学院水生生物研究所,武汉430072

出　　处：《水生生物学报》2012年第6期1171-1175,共5页Acta Hydrobiologica Sinica

基　　金：国家自然科学基金(30970185;40876071);中国科学院知识创新工程重要方向项目(KSCXZ-YW-Z-0932);国家水专项洱海课题(2008ZX07105-006)资助

摘　　要：常丝藻(Tychonema)是1988年由Anagnostidis和Komárek从颤藻属分离出来而新成立的蓝藻属,以纤细常丝藻(T.tenue)为模式种类。目前确认的常丝藻有纤细常丝藻、博多常丝藻(T.bornetii)和布氏常丝藻(T.bourrellyi)三个种类。我国已经有博多常丝藻的纪录,但是对模式种纤细常丝藻和它的相似种类布氏常丝藻却没有报道。在洱海中采集到布氏常丝藻(T.bourrellyi),研究并描述了该藻的藻丝颜色、藻细胞内含物的结构、藻体形态特征等。同时,通过藻种的分离培养技术,得到了布氏常丝藻的纯培养藻株,编号为CHAB663,并且测定了藻株的16S rRNA基因序列。测序结果表明,该藻株与T.bouurrellyi/T.tenue聚为一族。洱海分布的布氏常丝藻,是在欧洲以外首次发现此种藻类,也是我国的新纪录种。研究说明布氏常丝藻不仅仅分布在温带欧洲较为寒冷的水体中,在亚热带的水体中也可以存在。布氏常丝藻被认为是出现在轻微富营养化湖泊中,而我国洱海也被认为是富营养化的初级阶段的水体,这也表明,布氏常丝藻的出现对洱海的水环境状况起到了指示作用。此外,研究还对常丝藻属分类学问题进行了讨论。Tychonema was separated from Oscillatora and established as a new genus in 1988 by setting Tychonema tenue as the type species. This new genus was accepted and currently considered to include three species as T. tenue, T. bornetii and T. bourrellyi. T. bornetii was described from the Tibet Plateau, but no reports on type species and its related taxa of Tychonema were from China. The present study reported the occurrence of a Tychonema species from the Erhai Lake, and this species was morphologically identified as T. bouurrellyi based on its planktonic habit, trichome color and cellular content structure etc. Cultivated strains were also isolated, and comparative analyses on the sequences of 16S rDNA also confirmed that the T. bouurrellyi strain was tightly grouped with the strains of T. bouurrellyi/T, tenue. This is the first report on occurrence of T. bouurrellyi from outside of Europe, and T. bouurrellyi is also a newly recorded spe- cies in China. Such a result demonstrated that T. bouurrellyi can distribute extending from cold waters in North Europe to the warm waters in subtropical regions. It is interesting to coincide the occurrence of T. bouurrellyi with slightly eu trophicated waters since Lake Erhai has been regarded as an early phase of eutrophicated lake. The taxonomic problem and revision of the Tychonema genus was discussed in this study.

关 键 词：蓝藻 常丝藻属 布氏常丝藻 分类 洱海 

分 类 号：Q949.22[生物学—植物学]