Lumarie Pérez-Guzmán's Doctoral Scholarly Seminar

Lumarie Pérez-Guzmán, PhD Candidate in Ecosystem Science, will present What's in a Spoon of Soil? Millions of microbes, their fats, DNA, and the challenges of soil microbiology, as her Doctoral Sccholarly Seminar in 333C Kottman Hall.

Soil microorganisms play an important role in soil fertility. The mineralization of organic matter (OM), cycling of elements and stabilization of soil structure are carried out by a large community of microorganisms and involve a wide range of metabolic processes. For decades, most research in the soil system focused on methodological tools to study soil biomass quantity, its composition and activities. Among the challenges for quantifying biomass is the fact that approximately 1% of soil microflora are culturable by a range of conventional techniques and media. To overcome this, DNA analysis became a tool to describe quantity and diversity. However, there have been some difficulties when isolating amplifiable DNA due to the presence of interfering materials such as humic acids. Other methods include the use of cell membrane markers, and measuring microbial activity as proxies for biomass. The soil is a heterogeneous and complex system, and some of the treatments added to it during experiments further increase the methodological difficulties. This seminar will present some methods currently used for microbiological analysis, their advantages and limitations, and how the field is adopting an interdisciplinary and holistic approach to overcome some of these challenges.