• PDF

    Final published version, 197 KB, PDF-document

    Request copy


Scenedesmus acutus Meyen was cultured at four temperatures (9.5 degrees, 16.5 degrees, 24 degrees, and 29 degrees C) in standard medium or in medium with filtered water from a Daphnia culture, Growth was significantly reduced at low temperatures. At 9.5 degrees C it took more than a week before formation of eight-celled coenobia occurred in both the absence and presence of water from a Daphnia culture, At higher temperatures, formation of four- and eight-celled coenobia occurred more rapidly and was already observed in the presence of Daphnia water within 2 days, As cultures aged, also in the absence of Daphnia water, four-celled coenobia became dominant. At cold temperature, cell volume initially was significantly larger but declined after 3-4 weeks. Grazer-induced colony formation had occurred independent of the incubation temperature, but the number of cells per colony was increased with declining temperature. The morphological expression may be interpreted as a cyclomorphosis driven by nutrients, temperature, and chemical cues from gazers. [KEYWORDS: colony formation; cyclomorphosis; Daphnia; ecomorph; growth; infochemicals; phenotypic plasticity; Scenedesmus acutus; temperature Phenotypic plasticity; morphological-changes; daphnia-pulex; phytoplankton; growth; cyclomorphosis; light; transformation; infochemicals; consequences]
Original languageEnglish
Pages (from-to)1120-1126
JournalJournal of Phycology
Issue number6
Publication statusPublished - 1999

ID: 231915