CULTURE STUDIES ON THE LIFE-HISTORY OF CHORDARIA-LINEARIS (PHAEOPHYCEAE) FROM TIERRA-DEL-FUEGO, SOUTH-AMERICA

Studies of laboratory cultures of Chordaria linearis (Hooker et Harvey) Cotton from southernmost South America revealed that this species has an obligate sexual life history in which a macroscopic sporophyte alternates with a monoecious microscopic gametophyte. Sexual reproduction is isogamous and u...

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Bibliographic Details
Main Author: PETERS, AF
Format: Article in Journal/Newspaper
Language:English
Published: 1992
Subjects:
NOV
Online Access:http://hdl.handle.net/11370/3d2b778e-d7fa-43ef-a0e2-40bdf62f6c17
https://research.rug.nl/en/publications/culture-studies-on-the-lifehistory-of-chordarialinearis-phaeophyceae-from-tierradelfuego-southamerica(3d2b778e-d7fa-43ef-a0e2-40bdf62f6c17).html
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Summary:Studies of laboratory cultures of Chordaria linearis (Hooker et Harvey) Cotton from southernmost South America revealed that this species has an obligate sexual life history in which a macroscopic sporophyte alternates with a monoecious microscopic gametophyte. Sexual reproduction is isogamous and under photoperiodic control. Gametes are produced only in short days, whereas in long days, asexual zoospores are formed that recycle the gametophyte generation. Unfused gametes develop into gametophytes, and sporophytes originate only from zygotes. Unlike other sexual members of the Chordariales, gametes of C. linearis have a reduced stigma and do not show phototaxis. They are released at the beginning of the night, not in the morning. In nature, C. linearis seems to be regularly infected by a dictyosiphonalean epiphyte resembling the rare arctic species Trachynema groenlandicum (Lund) Pedersen. The epiphyte is responsible for previous contradictory results obtained in laboratory cultures of C. linearis. This is the first record of Trachynema in the southern hemisphere.