Natural History and Biodiversity FREE-LIVING SOIL NEMATODE POPULATION DIVERSITY DYNAMICS AT AN ASIMINA TILOBA SITE IN VIRGINIA

FREE-LIVING SOIL NEMATODE POPULATION DIVERSITY DYNAMICS AT AN ASIMINA TILOBA SITE IN VIRGINIA. Sarah R. Marzec & Theresa M. Grana, Department of Biological Sciences, Univ. of Mary Washington, Fredericksburg VA, 22401. Nematodes are microscopic roundworms that are highly successful in many environments. The model organism Caenorhabditis elegans is specifically a free-living nematode which can be found in soil but has been mostly isolated from anthropogenic habitats. Little is known about the environmental factors that affect C. elegans and where it is proliferate in nature. Information on ecological factors affecting Caenorhabditis species will be useful in identifying selective pressures that can influence genomic changes. The goals of this study are to find C. elegans and other Caenorhabditis species and shed light on relationships between the ecological factors and proliferating populations of nematodes. An Asimina tiloba site provides a natural Virginian habitat with a food source for Caenorhabditis species. This site is sampled every two weeks and any relevant ecological factors are recorded for the duration of a year. Nematodes are isolated from each soil sample and are separated based on morphology. The life stages of the nematodes from each sample are recorded and then the nematodes are sequenced for species identification. At present, five samples have been collected and several strains of nematodes have been isolated among and within the samples. All nematodes have shown to be in the dauer life-stage, a non-feeding migratory stage, showing that there are no established colonies. This is most likely due to the cold weather and we expect future results taken between the months of May through October to show proliferating populations.