Association between fertilizer-mediated changes in microbial communities and Aedes albopictus growth and survival

Abstract

Contamination of aquatic habitats with anthropogenic nutrients has been associated with an increase in mosquito larval populations but the underlying mechanisms remain poorly understood. We examined the individual and combined effects of two synthetic fertilizers (ammonium sulfate and potassium chloride) on Aedes albopictus survival, development time, and sex ratio. The bacterial and fungal communities of water samples from different fertilizer treatments were also characterized by MiSeq sequencing of the 16S rRNA gene (bacteria) and internal transcribed spacer 1 (fungi) and their relationship with mosquito survival and development determined. Mosquitoes from ammonium sulfate treatment had significantly lower survival rates and longer development times compared to those from control, potassium chloride or a mixture of the two fertilizers. Fertilizer treatment had no significant effects on Ae. albopictus sex ratio although ammonium sulfate treatment tended to be more biased towards males relative to the other treatments. There were no significant effects of fertilizer treatment on fungal communities. However, potassium chloride treatments had lower bacterial diversity compared to the other treatments and the bacterial community structure of control and potassium chloride treatments differed significantly from that of ammonium sulfate and a mixture of the two fertilizers. Microbial composition but not diversity was significantly associated with mosquito survival and development. These findings suggest that anthropogenic nutrients can have a profound impact on mosquito survival and development. In addition to any potential direct effects on mosquito physiology, our results suggest that fertilizers can act indirectly by disrupting the microbial communities that provide a critical food resource for mosquito larvae.

Aedes spp. and Their Microbiota: A Review

“…Aedes spp. microbiota is composed primarily by Gram-negative aerobic and facultative-anaerobic bacteria, as generally occurring in other mosquito species (Wang et al, 2011; Boissière et al, 2012; Osei-Poku et al, 2012; Coon et al, 2014, 2016a,b; Gimonneau et al, 2014; Duguma et al, 2015; Muturi et al, 2016b; Valzania et al, 2018). Only two obligate anaerobe taxa have been detected in Aedes spp.…”

“…Anthropogenic activities also impact the bio-geochemical properties of breeding sites, and, in turn, affect mosquito microbiota. Fertilizers containing ammonium and phosphorous contaminating aquatic habitats are known to affect the development and abundance of bacteria (Muturi et al, 2016b), which are a nutrient source for Culicidae larvae (Merritt et al, 1992). The increasing abundance of residual antibiotics in the environment has been shown to impact the composition of the microbiota to which mosquitoes are exposed.…”

Mosquito vector‐associated microbiota: Metabarcoding bacteria and eukaryotic symbionts across habitat types in Thailand endemic for dengue and other arthropod‐borne diseases

“…Recent improvements in the exploration of microscopic organisms through the use of metagenomic PCR (Hugenholtz, Goebel, & Pace, 1998; Liles, Manske, Bintrim, Handelsman, & Goodman, 2003) and next‐generation sequencing (Logares et al., 2012) have allowed more accurate and sensitive documentation of these organisms. Several studies have characterized and compared mosquito bacterial microbiota in natural habitats (Akorli et al., 2016; Buck et al., 2016; Gimonneau et al., 2014; Minard et al., 2012, 2014, 2015; Tchioffo et al., 2015; Yadav et al., 2015; Zouache et al., 2010) but few have characterized eukaryotes and in such cases have targeted fungi (Muturi, Bara, Rooney, & Hansen, 2016; Muturi, Ramirez, Rooney, & Dunlap, 2016; Steyn, Roets, & Botha, 2016). We document mosquito microbiota composition and diversity for vector species Aedes aegypti , Aedes albopictus , and Culex quinquefasciatus across ecologically distinct, yet geographically proximate, habitats in Thailand where many mosquito‐borne diseases circulate.…”

Insights into the bacterial symbiont diversity in spiders

“…Most arthropods are infected with a variety of symbiotic bacteria, which generally affect their hosts in a number of ways, such as impacting on development, reproduction, and speciation (Brucker & Bordenstein, ; Duron et al., ; Goodacre, Martin, Thomas, & Hewitt, ; McFall‐Ngai, ), providing protection against natural enemies and pathogens (Oliver, Russell, Moran, & Hunter, ; Scarborough, Ferrari, & Godfray, ), supplying key nutrients (Brownlie et al., ; Douglas, ) and improving heat tolerance (Montllor, Maxmen, & Purcell, ). To provide insights into bacterial communities and the relationships between symbiotic bacteria and their hosts, research regarding bacterial diversity and bacterial communities within insects has recently increased (Bili et al., ; Monteiro et al., ; Muturi, Ramirez, Rooney, & Dunlap, ; Zhao et al., ). Spiders are perceived as important natural enemies for pests (Marc, Canard, & Ysnel, ; Nyffeler & Sunderland, ), and many researchers have focused their attention on the endosymbionts infection of spiders (Duron et al., ; Goodacre et al., ; Rowley, Raven, & McGraw, ) and the relationships between the endosymbionts (such as Wolbachia , Cardinium , Rickettsia and Spiroplasma ) and their spider hosts (Curry, ; Gunnarsson, Goodacre, & Hewitt, ; Martin & Goodacre, ).…”