Karely Salcedo-Rios
Research Mentor: Jacob Longmeyer
Mentor Department: Ecology & Evolutionary Biology, LSA
Author(s): Karely Salcedo-Rios, Jacob Longmeyer
Session: Session 5 (2:00 PM – 2:50 PM)
Presentation Type: Poster 130
Abstract
A study was undertaken to identify earthworm specimens collected from Puerto Rican coffee farms through morphological characteristics and DNA barcoding. Earthworms were observed under a stereoscope through which taxonomic features, namely, setae amount and pattern on the anterior and posterior ends, were utilized to distinguish morphospecies. Subsequently, a small representative group of each morphospecies was formed, and small portions were obtained from each specimen for digestion, DNA extraction and PCR of the CO1 gene. Gel electrophoresis was conducted on PCR products to determine success of amplification. Sanger sequencing of these products resulted in DNA sequences which were then compared against a large database to find regions of similarity and thus identity of the specimen. By means of these two methods of identification, most of the specimens collected were identified as the non-native earthworm Pontoscolex corethurus, while native earthworms like Onychochaeta borincana and Neotrigaster yukiyui made up a smaller portion of samples. In identifying these specimens, we obtain further information on the community composition of these earthworms and ultimately their roles as ecosystem engineers through their unique contributions to soil health and coffee production. Earthworms are especially important due to their mineralization of organic matter in the highly weathered, nutrient poor soils of tropical agricultural systems.
