Effects of Microcystis aeruginosa on life history of water flea Daphnia magna

Deng

Acta Biologica Hungarica

et al. 2015

Microcystis colonial size and concentration have detrimental effects on life history traits of Daphnia, but their detailed interactions have remained unclear so far. Our experiments show that the interaction between Microcystis colonial size and concentration on maturation time, life expectancy, net reproductive rate and innate capacity of increase in Daphnia similoides was significant. In all groups, the survival rate of D. similoides was 100% within 8 days. This value then declined quickly in the large-colony groups and in the SH group of Microcystis. Colonial M. aeruginosa significantly reduced the maturation time and body length at maturity of D. similoides. The number of offspring at first reproduction per female in the SH group of Microcystis was significantly higher than those in other groups. Net reproductive rate of D. similoides in the SL group of Microcystis was significantly higher than those in other groups of Microcystis. The innate capacity of increase of D. similoides in small-colony Microcystis groups was significantly higher than that in the large-colony groups. The results suggested that the effect of smallcolony Microcystis on the reproduction of Daphnia was positive under lower concentration, while their toxicity was intensitied under higher concentration when small-colony Microcystis were by Daphnia as food.

Section: Discussionmentioning

confidence: 96%

Section: Discussionmentioning

confidence: 99%

Combined effects of colonial size and concentration ofMicrocystis aeruginosaon the life history traits ofDaphnia similoides

Deng

Acta Biologica Hungarica

et al. 2015

“…According to the MC levels in this study, MCs could cause significant effects on physiological or behavioural processes, or even death to some macrophytes and nano-sized protozoa in Lake Taihu. Other studies in Lake Taihu also showed that the Microcystis blooms strongly inhibited the population growth of the water flea, Daphnia magna , by reducing their survival rates, individual growth rate, or gross fecundity [ 65 ]. In the worst case, cyanobacterial blooms can eliminate filter-feeding zooplankton and change the competitive relations among zooplankton, which may undermine the food chain and destroy the ecological balance in aquatic ecosystems [ 65 , 66 ].…”

Section: Discussionmentioning

confidence: 99%

A Systematic Investigation into the Environmental Fate of Microcystins and The Potential Risk: Study in Lake Taihu

Jia

Chen

Lauridsen

2016

Toxins

A systematic investigation was conducted in Lake Taihu in autumn of 2013 and 2014, in order to understand the environmental fate of microcystins (MCs) and evaluate the health risk from MCs. Samples of water, algal cells, macrophytes, shrimps and fish were taken to detect MCs by HPLC-MS/MS after solid phase extraction. Widespread MC contamination in water, algal cells, macrophytes, shrimps and fish was found in Lake Taihu. The ubiquitous presence of MCs in water, algal cells and biota was found in 100% of samples. MC accumulation was in the order of primary producer > tertiary consumer > secondary consumer > primary consumer. The highest levels of MCs in macrophytes, shrimps and fish tissue were found in Potamogeton maackianus, Exopalaemon modestus, and Hyporhamphus intermedius, respectively. The MCs level in shrimps and the tissues of three fish species, Neosalanx tangkahkeii taihuensis, Coilia ectenes and silver carp, was closely linked to their dietary exposure. Ceratophyllum demersum L. was an ideal plant for introduction into lakes to protect against Microcystis blooms and MCs, due to its ability to absorb nutrients, accumulate large amounts of MCs and tolerate these toxins compared to other macrophytes. The average daily intakes (ADIs) of MCs for Exopalaemon modestus and three fish species, Coilia ectenes, Hyporhamphus intermedius and Carassius carassius, were all above the tolerable daily intakes (TDI) set by the World Health Organization (WHO), implying there existed potential threats to human health.

“…Many studies can be found that investigate the negative effects of M. aeruginosa on Daphnia. One study showed that M. aeruginosa blooms could strongly inhibit the population growth of D. magna through depression of survival, individual growth and gross fecundity (Liu et al 2011). Another study showed that M. aeruginosa negatively affected the survival, development and reproduction of Daphnia (Huang et al 2020).…”

Section: Stressor Systemsmentioning

confidence: 99%

Microbiome mediated tolerance to biotic stressors: a case study of the interaction between a toxic cyanobacterium and an oomycete-like infection in Daphnia magna

Houwenhuyse¹,

Bulteel²,

Goel³

et al. 2021

Preprint

Studies on stressor responses are often performed in controlled laboratory settings. The microbial communities in laboratory settings often differ from the natural environment, which could ultimately be reflected in different stress responses. In this study, we investigated the impact of single versus simultaneous multiple stressor exposure on Daphnia magna life history traits and whether this tolerance was microbiome-mediated. Daphnia individuals were exposed to the toxic cyanobacterium Microcystis aeruginosa and a fungal infection, Aspergillus aculeatus like type. Three genotypes were included to investigate genotype-specific responses. Survival, reproduction and body size were monitored for three weeks and gut microbial communities were sampled and characterized at the end of the experiment. Our study shows survival in Daphnia was microbiome-mediated as survival was only negatively impacted when Daphnia received a lab microbial community. Daphnia which received a natural microbial community have a broader environmental pool of microbiota to randomnly and selectively take up and showed no negative impact on survival. Simultaneous exposure to both stressors also revealed an antagonistic interaction for survival. Fecundity and body size were negatively impacted by exposure to stress, however, responses were here not microbiome-mediated. In addition, genotype specific responses were detected for survival and fecundity, which could be linked with the selective capabilities of the Daphnia genotypes to select beneficial or neutral microbial stains from the environment.