Abstract

Epiphytic diatoms are essential primary producers in aquatic environments, but the relationship between them and their hosts is not well understood. The purpose of this project is to understand the specificity of a macroalgal host-epiphytic diatom relationship in Pentwater and Muskegon Lakes, and compare the epiphytic diatom communities of the invasive Nitellopsis obtusa to its close native relative, Chara contraria, using a metabarcoding approach. To these ends, host samples were collected monthly from July to September in 2020 (90 samples) and in June 2021 (55 samples). DNA was extracted from each sample and the plastid RUBISCO (rbcL) barcoding region of the diatom DNA was amplified using diatom-specific primers. Amplification success was ~ 60%. Samples with positive amplification are being prepared for diatom metabarcoding using an Illumina MiSeq platform currently. Ultimately, this study will provide us with better understanding of the macroalgal host-epiphytic diatom relationship.