| notes on freshwater and terrestrial algae from ny-alesund, svalbard (high arctic sea area). | field survey of algae and cyanobacteria from terrestrial and freshwater habitats in the vicinity of arctic ny-alesund, svalbard (790n) (high arctic sea area) was performed in june 2006. species diversity and abundance were evaluated by using epifluorescence microscopy and culturing methods. in total, 29 taxa in 25 genera were identified, of which leptolyngbya spp., trichormus sp. and chlamydomonas nivalis were abundantly present in almost every sample. in several locations, blooms were formed by ... | 2008 | 19195386 |
| phylogenetic and morphological evaluation of the genera anabaena, aphanizomenon, trichormus and nostoc (nostocales, cyanobacteria). | the heterocytous cyanobacteria form a monophyletic group according to 16s rrna gene sequence data. within this group, phylogenetic and morphological studies have shown that genera such as anabaena and aphanizomenon are intermixed. moreover, the phylogeny of the genus trichormus, which was recently separated from anabaena, has not been investigated. the aim was to study the taxonomy of the genera anabaena, aphanizomenon, nostoc and trichormus belonging to the family nostocaceae (subsection iv.i) ... | 2005 | 15653847 |
| comparison of light and dark nitrogenase activity in selected soil cyanobacteria. | frequency of heterocytes and nitrogenase activity (na) under light and dark cultivation conditions was determined in 12 cyanobacterial strains isolated from various soil habitats. in spite of a high variability, significant differences in na among the strains were found in response of light and dark cultivation. relatively high na (9.9-15.3 micromol/h c2h4 per g fresh mass) under light conditions and basal na after 12 h of dark cultivation were detected in anabaena, nodularia, tolypothrix, and 1 ... | 2004 | 15530010 |
| [nitrogen-fixing cyanobacterium trichormus variabilis of the lake baikal phytoplankton]. | a new filamentous cyanobacterial strain bac 9610 was isolated from the lake baikal pelagial. data obtained by light, scanning, and transmission electron microscopy, along with 16s rrna gene sequence analysis, allowed the bacterium identification as trichormus variabilis, previously known as anabaena variabilis. trichormus is a cyanobacterial genus not presented in the list of baikal plankton algae; a. variabilis also has not been previously detected in baikal phytoplankton. t. variabilis nitroge ... | 2008 | 19137721 |