ABSTRACT We hypothesised that at higher densities herbivorous rotifers through their allelochemicals affect the survival and reproduction of cladocerans. To test this, we separately cultured three rotifers (Brachionus calyciflorus, Brachionus havanaensis, and Plationus patulus) and three cladocerans (Ceriodaphnia dubia, Daphnia pulex, and Moina macrocopa). Chlorella vulgaris was used as food and reconstituted moderately hard water was used as medium. The conditioned-medium (CM) obtained from each of rotifer species was used to conduct cohort life table tests of cladocerans. SDS PAGE electrophoresis revealed the molecular weights of proteins present in the rotifer conditioned medium were 55–63 kDa. Compared to C. dubia and D. pulex, Moina was more resistant to rotifer-mediated chemicals. Gross reproductive rate of C. dubia was significantly stimulated by the rotifer-CM. However, gross and net reproductive rates of D. pulex were strongly reduced (72–85%) due to P. patulus-CM but not from the other two rotifer species. The rate of population increase of M. macrocopa was significantly reduced by the rotifer CM. Overall, about 46% (adverse effect: 24%; stimulatory impact: 22%) of the life history variables in controls significantly differed from rotifer-CM treatments, thus proving our hypothesis that rotifer-mediated allelochemicals had some effect on the cladoceran life history variables.

中文翻译：

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轮虫介导的化感物质对枝角类动物（枝角类）生活史的影响

摘要 我们假设在较高密度下，草食性轮虫通过其化感物质影响枝角类动物的生存和繁殖。为了测试这一点，我们分别培养了三种轮虫（Brachionus calyciflorus、Brachionus havanaensis 和 Plationus patulus）和三种枝角类动物（Cerodaphnia dubia、Daphnia pulex 和 Moina macrocopa）。普通小球藻被用作食物，而重构的中等硬度的水被用作培养基。从每个轮虫物种中获得的条件培养基 (CM) 用于进行枝角类动物的队列生命表测试。SDS PAGE 电泳显示轮虫条件培养基中存在的蛋白质的分子量为 55-63 kDa。与 C. dubia 和 D. pulex 相比，Moina 对轮虫介导的化学物质更具抵抗力。总繁殖率 C. dubia 受到轮虫-CM 的显着刺激。然而，由于 P. patulus-CM 而不是来自其他两种轮虫物种，D. pulex 的总繁殖率和净繁殖率显着降低（72-85%）。轮虫CM显着降低了M. macrocopa的种群增长率。总体而言，对照组中约 46%（不利影响：24%；刺激影响：22%）的生活史变量与轮虫-CM 处理显着不同，从而证明了我们的假设，即轮虫介导的化感物质对枝角类动物的生活史有一些影响变量。