| Autor: |
Eduardo J. Cáceres, Karina Mariel Michetti, Patricia Ines Leonardi |
| Rok vydání: |
2002 |
| Předmět: |
|
| Zdroj: |
Algological Studies/Archiv für Hydrobiologie, Supplement Volumes. 105:111-124 |
| ISSN: |
0342-1120 |
| DOI: |
10.1127/algol_stud/105/2002/111 |
| Popis: |
Akinete formation in Stigeoclonium tenue (AG) KUTZ began under unfavourable conditions (exhaustion of nutrients and/or evaporation of the culture medium). Cells from both prostrate and erect portions produced akinetes. A gradual change in the shape of vegetative cells was observed. They lost their typical straight edges and acquired an oval contour with constrictions at the level of the transverse cell walls. At the ultrastructural level, the changes were: 1) accumulation of starch and lipids as reserve substances; 2) disorganization of the chloroplast; 3) reduction of the vacuole until it disappeared in mature akinetes; 4) thickening of the wall resulting from the synthesis of both an additional new own wall next to the parental wall and a mucilage external layer; 5) disorganization of the plasmodesmata in the transverse walls of vegetative cells. All of these drastic cytological changes are essential to the development of akinetes which provide S. tenue with an effective survival mechanism under unfavourable conditions. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
