KNAW Repository

Morphological changes in Scenedesmus induced by infochemicals released in situ from zooplankton grazers

Lürling, M. and Van Donk, E. (1997) Morphological changes in Scenedesmus induced by infochemicals released in situ from zooplankton grazers. Limnology and Oceanography, 42, 783-788. ISSN 0024-3590.

[img]PDF - Published Version
Restricted to KNAW only

1335Kb

Official URL: http://www.jstor.org/stable/2839126

Abstract

Biochemical substances released from Daphnia galeata induced colony formation in the green alga Scenedesmus acutus. Normally this strain consisted mainly of single cells in cultures. However, if exposed for 48 h to either water with live Daphnia or to O.1-mu m filtered water from a culture with Daphnia present, these unicellular "Chodatella" stages were induced to form colonies (coenobia). Colony induction was not unique to Daphnia; other zooplankters (rotifers and copepods) were able to induce colonies in S. acutus as well. This morphological response could also be evoked when Scenedesmus was exposed to 0.1-mu m filtered lake water during high zooplankton abundances. Especially during early spring, a clear relationship was found between rotifer abundance and colony formation in our test alga in the laboratory. Filtered lake water, incubated nonaxenically for at least 2 d at 20 degrees C, did not induce colony formation, possibly due to microbial degradation. The morphological changes in Scenedesmus could promote grazing resistance in small zooplankters and can be interpreted as an adaptive antipredator strategy. [KEYWORDS: DIEL VERTICAL MIGRATION; BLUE-GREEN-ALGAE; DAPHNIA; INDUCTION; CHLOROPHYCEAE; DEFENSES; FISH]

Item Type:Article
Institutes:Nederlands Instituut voor Ecologie (NIOO)
ID Code:10508
Deposited On:25 Nov 2011 01:00
Last Modified:31 Mar 2014 10:24

Repository Staff Only: item control page