Offspring performance of Daphnia magna after short-term maternal exposure to mixtures of microcystin and ammonia

Abstract

During degradation of cyanobacterial blooms, some derived pollutants are released to the waters and last for a while before returning to normal levels. To assess whether the offspring of exposed Daphnia was affected by their maternal experience, we exposed mother Daphnia magna to mixtures of unionized ammonia (0, 0.30, and 0.48 mg L(-1)) and microcystin-LR (0, 10, 30, and 100 μg L(-1)) for 10 days and then immediately moved their offspring to a toxicant-free environment. The offspring were cultured for 21 days to record their survival, development, and reproduction. Results showed that the survival of the offspring of D. magna that experienced high doses of mixed toxicants decreased significantly, but there was no significant difference in development among the survivors of the offspring from different maternal treatments. However, reproductive performances significantly differed among the offspring from different maternal treatments, indicating that there existed a maternal effect in the offspring of D. magna that experienced high levels of mixed toxicants.

On the successful use of a simplified model to simulate the succession of toxic cyanobacteria in a hypereutrophic reservoir with a highly fluctuating water level

“…Large-sized Daphina can consume small-sized Microcystis colonies with a diameter generally less than 50 µm but they have difficulties in ingesting large sized colonies. The ingestion rate of Microcystis aeruginosa depends on the duration of the application of Daphnia, presence of microcystin toxin (Zhu et al 2015), and the presence of fish that affect the process of grazing (Sarnelle, 2007).…”

Individual variation in plasticity dulls transgenerational responses to stress

“…One potential explanation for the lack of treatment differences in the second experimental generation is that maternal exposure to cyanobacteria did not influence the phenotypes of offspring. This deserves consideration as most prior studies have used toxic Microcystis to test for the presence of transgenerational plasticity (Beyer & Hambright, ; Gustafsson et al, ; Jiang et al, ; Lyu et al, ; Peng et al, ; Zhu et al, ). Here, we used a non‐toxic strain of Anabaena which may influence the extent to which Daphnia respond across generations (Walsh et al, ).…”

“…For instance, several studies have discovered evidence for adaptive transgenerational responses (e.g., physiological, morphological) to cyanobacteria that could ameliorate negative fitness consequences over time (Gustafsson, Rengefors, & Hansson, ; Jiang et al, ; Lyu et al, ; Peng et al, ; Schwarzenberger & Von Elert, ). Yet, other reports highlight that maternal stress from cyanobacteria generates maladaptive effects (e.g., reduced growth, survival) in offspring, which could have a compounding negative influence on the fitness of subsequent generations (Faassen, García‐Altares, Mendes e Mello, & Lürling, ; Radersma, Hegg, Noble, & Uller, ; Zhu et al, ).…”

“…Therefore, our predictions mirrored previous findings; we predicted that Daphnia would mature at a later age and smaller size and produce fewer offspring when fed cyanobacteria as opposed to high‐quality food. Such negative consequences of cyanobacteria during development can have maladaptive effects on subsequent generations (Beyer & Hambright, ; Zhu et al, ). However, adaptive transgenerational responses can also be present in populations and may counteract or even outweigh the influence of maladaptive effects (Lyu et al, ; Schwarzenberger & Von Elert, ).…”

“…Therefore, our predictions mirrored previous findings; we predicted that Daphnia would mature at a later age and smaller size and produce fewer offspring when fed cyanobacteria as opposed to high-quality food. Such negative consequences of cyanobacteria during development can have maladaptive effects on subsequent generations (Beyer & Hambright, 2017;Zhu et al, 2015).…”