Differences in Bacterial Community Structure on <i>Hydrilla verticillata</i> and <i>Vallisneria americana</i> in a Freshwater Spring

Abstract

The phylogenetic composition of the epiphytic bacterial community of an invasive aquatic plant (Hydrilla verticillata) and a native species (Vallisneria americana [eelgrass]) of the Wakulla Spring (Florida) was investigated, along with the water column bacterial composition, using clone libraries of the 16S rRNA genes. The bacterial clones from three clone libraries were classified into 182 operational taxonomic units (OTUs), most of which were affiliated with bacterial divisions commonly found in freshwater ecosystems. Based on the identified classes, the bacterial communities on eelgrass and Hydrilla were distinct, such that Planctomycetes, Cyanobacteria, Bacilli and Actinobacteria were found on eelgrass and in the water column but not on Hydrilla. On the other hand, Deltaproteobacteria and Verrucomicrobiae were found on Hydrilla and in the water column but not on eelgrass. Further distinctions observed were that Armatimonadia and Deinococci were found only on Hydrilla while Gemmatimonadetes was found only on eelgrass. Our results indicated differences between the epiphytic bacterial community on the two plants and the water column at the species level, but an even representation of the most abundant phylogenetic taxa (classes) in all three libraries was revealed. Statistical comparison of the retrieved sequences confirmed that the three libraries did not differ significantly at the community level (LIBSHUFF, p <0.05).

Responses of bacterial community structure and denitrifying bacteria in biofilm to submerged macrophytes and nitrate

“…Consistent with these results (Table S3), Proteobacteria was the most abundant phylum on the leaf surfaces of aquatic angiosperms from Chesapeake Bay24. Proteobacteria, Bacteroidetes, Chloroflexi, Firmicutes, Actinobacteria and Verrucomicrobia were the most abundantly represented phyla on the leaves of lettuce25 and Potamogeton crispus 26.…”

Bacterial community structure in freshwater springs infested with the invasive plant species Hydrilla verticillata

“…Plant species are known to produce specific exudates (Söderberg et al, 2002), different leaching metabolites and proportions of chemicals (Fiehn et al, 2000) which can impact the bacterial community structure. These findings support previous results in our laboratory in which the epiphytic bacterial community structure of Hydrilla was found to be distinct from that on the native plant species eelgrass (Gordon-Bradley et al, 2013). …”

Mn accumulation in a submerged plant Egeria densa (Hydrocharitaceae) is mediated by epiphytic bacteria

“…Similarly, species‐specific communities of epiphytic bacteria have been reported in several aquatic plants (Gordon‐Bradley et al . ). rRNA genes of cyanobacteria were detected only when plants with visible dark biofilms were assayed (Fig.…”