The AMP Index as a Metabolic Indicator of Health of Microbial Populations: Proof-of-concept for soil and water microbial communities Luisa Ikner (UA), Dan Quintanar (City of Tucson Water), and Ian Pepper (UA) RESEARCH PROGRESS REPORT UA-09-S2018 STATUS: Continuing, additional funding requested Relationship to Technology Roadmap: Municipal Water Use Practices and Wastewater Reuse Background: Key Findings To-Date: Commercial, portable kit measures total microbial load in soil or water by measuring ATP, with conversion to microbial equivalents Additional kit measures AMP AMP Index (AMPi) values (AMP:ATP) indicate metabolic stress levels of microbial communities within 10 minutes Changes in the AMP Index correspond with the induction and reduction of soil moisture stress conditions over time Consistent trends observed for all 5 soil types Magnitude of AMPi values vary by soil type/ community Objectives: Budget Requested: Evaluate the use of the AMP Index as a near real-time indicator of nutrient stress in soils Determine the effects of several nutrient amendments on the metabolic activity levels of soil microbes over time Personnel $10,000 Operations $ 5,000 Total $15,000 Approach: Project Duration: December 1, 2018 – June 30, 2019 Five different soil types collected under dry, hot conditions Microbial assays: HPCs, dehydrogenase activity, ATP and AMP assays Calculate pre-amendment Microbial Equivalents and AMP Indices Amend soils with a variety of nutrients including glucose, commercial-grade fertilizer, compost, and Class B biosolids Assess changes in AMPi over time under constant and variable soil moisture conditions Water & Environmental Technology Center