(661.6) eDNA Analysis of Goat-Grazed Rhamnus cathartica Soil Microbial Communities

Poster Board Number: A241

Paula Soneral (Bethel University), Alesia Khomcyk (Bethel University), Raymond Enke (James Madison University), Bruce Nash (Cold Spring Harbor Laboratory), Jeremy Seto (New York City College of Technology)

Biological invasions of exotic species pose a significant threat to local biodiversity and ecosystem services. Redistribution of plant species in particular disrupts key structure-function relationships in the soil by altering the composition of microbial taxa. This study combines environmental DNA analysis with a goat-grazing intervention to investigate the taxonomic structure of soil microbiomes interacting with the invasive plant, Rhamnus cathartica (common Buckthorn). 16S (515F/806R) metabarcodes were amplified from soil DNA harvested before and after a goat-grazing regimen on buckthorn-invaded and control plots. Samples were sequenced on an Illumina iSeq, then analyzed using the DNA Subway Purple Line (QIIME 2.0) to process sequencing reads and calculate diversity indices. PCoA visualizations of Jaccard Beta diversity patterns revealed differences in community composition between buckthorn and control soils, but no effects from goat grazing. Five dominant taxa were identified in no-buckthorn control soils, accounting for 35 +/- 9.6 SD% of the average relative abundance of total sequences. Genus DA101 notably demonstrated the largest decrease in average relative abundance in the buckthorn and goat-grazed soils (% decrease = 6.4 +/- 2 SD), whereas the evenness of other taxa increased. Overall, buckthorn soil showed significant increases in Pielou’s taxonomical evenness (Kruskal-Wallis H(2, N=29) = 10.9; p=0.004), but goat grazing had no impact on this score (pgt;0.01). Faith’s phylogenetic diversity scores showed no significant differences between buckthorn, goat-grazed, and control soils (Kruskal-Wallis H(2, N=31) = 2.2; p=0.32). Taken together, these preliminary results illustrate that buckthorn increases taxonomical evenness but has no effect on overall phylogenetic diversity of soil communities. Moreover, buckthorn goat-grazing had little impact on soil community structure. Future studies will investigate the role of DA101 on buckthorn suppression as a possible mitigation strategy for this invasive species.

lt;a href="https://www.nsf.gov/awardsearch/showAward?AWD_ID=1821657amp;amp;HistoricalAwards=false"gt;NSF IUSE Grant #1821657lt;/agt;