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. 2012;7(12):e50969.
doi: 10.1371/journal.pone.0050969. Epub 2012 Dec 5.

The bacterial composition within the Sarracenia purpurea model system: local scale differences and the relationship with the other members of the food web

Sarah M Gray  1 , Denise M Akob, Stefan J Green, Joel E Kostka
Affiliations

The bacterial composition within the Sarracenia purpurea model system: local scale differences and the relationship with the other members of the food web

Sarah M Gray et al. PLoS One. 2012.

Abstract

The leaves of the carnivorous pitcher plant, Sarracenia purpurea, contain a microscopic aquatic food web that is considered a model system in ecological research. The species identity of the intermediate and top trophic level of this food web, as well the detritivore midge, are highly similar across the native geographic range of S. purpurea and, in some cases, appear to have co-evolved with the plant. However, until recently, the identity, geographic variation, and diversity of the bacteria in the bottom trophic level of this food web have remained largely unknown. This study investigated bacterial community composition inside the leaves of S. purpurea to address: 1) variation in bacterial communities at the beginning of succession at the local scale in different areas of the plant's native geographic range (southern and mid-regional sites) and 2) the impacts of bacterial consumers and other members of the aquatic food web (i.e., insects) on bacterial community structure. Communities from six leaves (one leaf per plant) from New York and Florida study sites were analyzed using 16S ribosomal RNA gene cloning. Each pitcher within each site had a distinct community; however, there was more overlap in bacterial composition within each site than when communities were compared across sites. In contrast, the identity of protozoans and metazoans in this community were similar in species identity both within a site and between the two sites, but abundances differed. Our results indicate that, at least during the beginning of succession, there is no strong selection for bacterial taxa and that there is no core group of bacteria required by the plant to start the decomposition of trapped insects. Co-evolution between the plant and bacteria appears to not have occurred as it has for other members of this community.

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Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Figure 1
Figure 1. Beta-diversity of bacterial communities present in leaves of S. purpurea from NY and FL sampling locations using Bray-Curtis dissimilarity.
MDS plots comparing bacterial community structure within sampling sites and among leaves were generated based on organismal classification based on colony morphology of culturable bacteria (A) and 16S rRNA gene sequences, identified at the genus-level using the RDP classifier (B). Data were based on square-root transformed Bray-Curtis similarity. Each symbol represents the bacterial community in one pitcher plant leaf (FL = Florida; NY = New York).
Figure 2
Figure 2. Beta-diversity of bacterial communities present in leaves of S. purpurea from NY and FL sampling locations using the Unifrac metric.
Bacterial community structure was assessed by sequencing 16S rRNA genes as described in the text. A phylogenetic tree was generated by inserting partial gene sequences recovered in this study into a tree based on near-full length sequences, implemented within the software package ARB. The phylogenetic tree was analyzed using the software package Unifrac, and a pair-wise distance matrix was generated for comparison of the bacterial community in each leaf. This matrix was used to generate a MDS plot, demonstrating distinct bacterial communities in FL and NY leaves.
Figure 3
Figure 3. Frequencies of bacterial phylogenetic lineages in Sarracenia purpurea water from Florida and New York.
Calculations were made based on the total number of sequences in each 16S rRNA gene library associated with a single taxon.
See this image and copyright information in PMC

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References

    1. Hegner RW (1926) The protozoa of the pitcher plant, Sarracenia purpurea . Biological Bulletin 50: 271–276.
    1. Addicott JF (1974) Predation and prey community structure: an experimental study of the effect of mosquito larvae on the protozoan communities of pitcher plants. Ecology 55: 475–492.
    1. Kneitel JM, Miller TE (2002) The effects of resource and top-predator addition to the inquiline community of the pitcher plant Sarracenia purpurea . Ecology 83: 680–688.
    1. Miller TE, Kneitel JM, Burns JH (2002) Effect of community structure on invasion success and rate. Ecology 83: 898–905.
    1. Gray SM, Miller TE, Mouquet N, Daufresne T (2006) Nutrient limitation in Sarracenia purpurea microcosms. Hydrobiologia 573: 173–181.

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