Morphological changes in Scenedesmus induced by infochemicals released in situ from zooplankton grazers
Morphological changes in Scenedesmus induced by infochemicals released in situ from zooplankton grazers
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DOI：
10.4319/lo.1997.42.4.0783
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发表时间：
1997-06
影响因子：
4.5
通讯作者：
M. Lürling;E. van Donk
中科院分区：
文献类型：
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作者：
M. Lürling;E. van Donk
盔状水蚤释放的生化物质诱导绿色藻栅藻的菌落形成。正常情况下，该菌株主要由培养物中的单细胞组成。然而，如果暴露于含有活水蚤的水或来自含有水蚤的培养物的0.1 µm过滤水48 h，这些单细胞“Chodatella”阶段被诱导形成菌落（共生体）。集落诱导不是水蚤所独有的，其他动物（轮虫和桡足类）也能在S. Acutus也是。当栅藻在高浮游动物丰度期间暴露于0.1 µm过滤湖水时，也可以诱发这种形态学反应。特别是在早春，我们在实验室的测试池中发现了轮虫丰度和群体形成之间的明显关系。过滤后的湖水，在20°C下无菌培养至少2天，没有诱导菌落形成，可能是由于微生物降解。栅藻的形态变化可以提高小型动物的抗放牧能力，可以解释为一种适应性的反捕食策略。
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 0.1‐µm 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‐µm 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°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.