Lei Lamei, Lai Shuyan, Liu Wei, Li Yaokai, Zhang Huiping, Tang Yali
Department of Ecology, Jinan University, Guangzhou, China.
Front Microbiol. 2023 Nov 16;14:1292277. doi: 10.3389/fmicb.2023.1292277. eCollection 2023.
Feeding effects are crucial for evaluating the capacity of zooplankton to regulate phytoplankton populations within freshwater ecosystems. To examine the impact of the bloom-forming cyanobacteria , which occurs in tropical and subtropical freshwaters, on the growth of zooplankton in relation to toxins, filament length and fatty acid content, we fed with only (cylindrospermopsin (CYN)-producing and non-CYN-producing, as the negative controls), only (as the positive control) and a mixed diet containing (CYN-producing and non-CYN-producing) and . Consequently, our findings revealed that the toxic effect of CYN-producing strains on was mitigated by the coexistence of containing stearidonic acid (SDA, C18:4 ω3) in mixed diets. This was evident in the elevated survival rate compared that from diets containing only and a significantly higher reproduction and population intrinsic increase rate compared to diets consisting of only or . Additionally, a strong positive correlation was observed between arachidonic acid (ARA, 20:4ω6) and the population intrinsic increase rate of ; notably, strains were found to be rich in the ω6 polyunsaturated fatty acid ARA. These outcomes reinforce the crucial role of polyunsaturated fatty acids in predicting the population increase of crustacean zooplankton, which has long been neglected. Furthermore, our results underscore the potential effectiveness of zooplankton, particularly in temperate lakes, in controlling CYN-producing populations.
摄食效应对于评估浮游动物调节淡水生态系统中浮游植物种群的能力至关重要。为了研究在热带和亚热带淡水中出现的形成水华的蓝藻对浮游动物生长的影响，涉及毒素、丝状体长度和脂肪酸含量，我们分别投喂仅（产柱孢藻毒素（CYN）和不产CYN的，作为阴性对照）、仅（作为阳性对照）以及含有（产CYN和不产CYN的）和的混合饲料。因此，我们的研究结果表明，混合饲料中含有硬脂酸（SDA，C18:4ω3）的共存减轻了产CYN菌株对的毒性作用。这在与仅含的饲料相比存活率升高以及与仅由或组成的饲料相比繁殖率和种群内在增长率显著更高方面表现明显。此外，花生四烯酸（ARA，20:4ω6）与的种群内在增长率之间观察到强烈的正相关；值得注意的是，菌株富含ω6多不饱和脂肪酸ARA。这些结果强化了多不饱和脂肪酸在预测长期被忽视的甲壳类浮游动物种群增长方面的关键作用。此外，我们的结果强调了浮游动物，特别是在温带湖泊中，在控制产CYN种群方面的潜在有效性。
