By Mariah Cashbaugh, Ph.D. student and Dr. Lee Miller – Purdue University

Turfgrass pathogens diminish the quality, aesthetics, and utility of turfgrasses. In golf courses, putting greens require careful management to maintain the pristine playing conditions demanded by players. This often involves multiple fungicide applications throughout the season to keep common pathogens under control. Pathogen monitoring to time these applications using traditional methods require destructive plant and soil sampling.

Many pathogens including dollar spot, brown patch, and pythium have unique requirements and seasonality caused by fluctuations in the soil temperature, moisture, and nutrient content. Predictive models utilizing air temperature and rainfall can help golf course managers predict when outbreaks might occur, but they cannot consider all of the site specifics. A more efficient method of pathogen detection, diagnosis, and monitoring may utilize the putting green drainage system. USGA drainage systems layer a 30 cm sand base on 10 cm of pea gravel to create a perched water table that flushes percolated water into a 10 cm drainage pipe below. Little is known about the microbiome of drainage water in these systems, nor the rate of water flow through these perched water tables throughout the season.

This field season, we will be collecting flow rate data and developing a collection vessel that can be attached to a drainage outlet. Our goal is to assess if pathogen inoculum is transmitted through percolated ground water and can be detected using modern molecular techniques. If successful, a more a comprehensive look at both the spatial and temporal dynamics of pathogen inoculum and microbial diversity may be gained. This information may translate into more effective timing of preventive treatments and reduction in overall fungicide use. If you are interested in getting your course involved in this pioneering study, please scan the QR code below to contact us at turfpath@purdue.edu.