Nematode Communities of Great Smoky Mountains National Park.

Bernard, Ernest

"The PIs proposed to document and describe nematode biodiversity within the park. They conducted some initial surveys of soil nematodes in the 19 biodiversity reference plots established for the ATBI. They hoped to study additional nematode groups, including those commensal within millipede intestines, associates and parasites of bark beetles, and nematodes found within plants, but the National Science Foundation proposal was not funded. In 2011, the co-PI collected soil samples from six ATBI plots. Some of the samples were grouped to be typical of the whole plot and some were collected specifically at the roots of targeted plant species. Nematode abundance was lowest on the summit of Mt. LeConte and highest at Albright Grove. Twelve species of the plant parasite group Criconematina have been identified, with images taken. Three of these have been incorporated into a DNA barcode project for this group. For genera of the predaceous nematode order Mononchida were found in the samples thus far. Processing of samples continues. Work in 2013 was partially prevented by the government shutdown. A limited effort in June at Twin Creeks produced 34 individual nematode specimens, representing the major trophic groups of bacterial-feeding, fungal-feeding, insect-associates, insect-parasites and other invertebrate-parasites (millipedes), plant-associates, plant-parasites, nematode-predators and virus vectors. Soil collected from 17 ATBI plots and a few other locations produced 593 specimens of nematodes. Of those, 375 were from the suborder Criconematina and have been digitally imaged, measured and prepared for PCR. These comprise over 18 morphospecies (apparent species based on morphology) from 10 described genera. Preliminary results from DNA sequence analysis of the 18 criconematid morphospecies found in the GRSM suggest that most of the morphospecies are actually cryptic species, each composed of several distinct phylogenetic lineages. Data is presented on-line at http://nematode.unl.edu/COI-ProteinTree_4-25-14.html. 32 more soil samples were collected from the 19 ATBI plots in 2015, particularly from around the roots of cherry, beech, chestnut, oak and yellow buckeye to look for relationships between tree and nematode species. Bernard initiated this study in the 1980s but was not able to pursue it successfully at that time."

Nematode Communities of Great Smoky Mountains National Park.

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