Microbial ecology is a growing research interest within the field of ecology due to increasing awareness of valuable microbial effects on plant and ecosystem health. Beneficial microbes can confer strong plant growth promoting effects to plants; fungal and bacterial microbes in the rhizosphere provide plants with necessary nutrients, and endophytes within plant tissues modulate plant growth and stress hormones. These microbe/plant relationships have been harnessed to benefit plant growth in agriculture and ecological restoration. Recent developments in metagenomic technology have made it cost-efficient and feasible for non-microbiologists to survey the microbial community in an ecosystem of interest. Using Next Generation Sequencing (NGS) techniques, we examined the bacterial endophyte community within imperiled Puget Prairie ecosystems. We sampled 17 plant species across 56 plots, for a total of 335 stem samples. Samples were surface sterilized and rRNA from bacterial endophytes was extracted, then the V4 region of the 16s rRNA gene was sequenced. Raw reads were processed through a bioinformatics pipeline and assigned to operational taxonomic units (OTU’s). Weighted and unweighted UniFrac distance measures and PERMANOVA were used to evaluate differences in endophytic community composition between plant samples and sampling locations. PCoA was performed to confirm differences indicated in PERMANOVA.
Results/Conclusions
Preliminary results from 40 samples generated 1588 OTU’s. A large percentage of OTU’s in the preliminary data (upwards of 50% in some cases) are shared between plant species, but significant differences were also identified between plant species and between sampling locations. Several taxa of known beneficial endophytes were discovered inhabiting plant tissues, including Pseudomonas spp., Bacillus spp., and Flavobacterium spp. Some plant species generated significantly more OTU’s than other plant species, indicating that some plant species may act as hosts for a broader range of endophytes than others; on average, Achillea millefolium samples contained 707 OTU’s while Aquilegia formosa samples only contained 585 OTU’s. The knowledge gained through microbial research directly benefits land managers hoping to improve their field crops or restoration sites with microbial diversity and community interaction enhancing techniques. Next Generation Sequencing technology can be applied in fields beyond microbial ecology, with significant gains in scientific knowledge possible where these techniques are used. With further research, metagenomics can be used to enhance our understanding of ecosystems from micro to macro scales, and equipped to improve land management techniques.