The Identification of Bacteria Species in Vermicompost

Student Name: Gloria Liou

UCD Department: USDA Agricultural Research Services

UCD Mentor: Dr. Daniel Kluepfel

Standard microbial culture-based methods were used to study the composition and diversity of three vermicompost samples (Terra Vesco, Sonoma, CA, USA). Bacterial colonies were isolated from vermicompost using serial dilutions. The amplification and sequence analysis of 16S rDNA from 39 isolates showed a high percentage (79%) of Actinobacteria sp., especially Arthrobacter sp. (54%) and Streptomyces sp. (15%). Proteobacteria and Firmicutes sp. were also detected. The level of bacteria diversity in the soil supported the idea that microorganisms in vermicompost may be able to outcompete and reduce soil-borne pathogen populations, making vermicompost a viable disease-control method for the agriculture industry.