Assessment of Temperature and Time Following Application as Predictors of Propiconazole Translocation in Agrostis stolonifera

Abstract

Propiconazole is a xylem-mobile fungicide used to suppress psychrophilic fungi on amenity turfgrass in temperate climates. The ability of turfgrass plants to translocate propiconazole during cold temperatures is unclear, with important implications for adequate fungal suppression and potential environmental contamination. We assessed the impact of temperature and time following application on the amount of propiconazole translocated into individual turfgrass plants and created a linear mixed-effects (LME) model to predict propiconazole uptake. Propiconazole was applied near the base of individual creeping bentgrass plants grown in controlled environment chambers at four different temperatures (22, 14, 10, and 1 °C). Propiconazole quantification was performed on individual 1 cm leaf segments using liquid chromatography-tandem mass spectrometry and assessed 24, 48, and 72 h following application. Propiconazole concentrations were consistently highest in the lowest leaf segment (0-1 cm above the soil surface) regardless of temperature or time following application. Peak propiconazole concentrations were observed between 24 and 48 h after application. Using the LME model, leaf segment correlated most strongly with higher propiconazole concentration, followed by time after application and temperature. Our results indicate that propiconazole translocation in amenity turfgrass is primarily limited to the lowest segment of the plant regardless of temperature or time following the application. These findings provide important information for the effective use of xylem-mobile fungicides to treat low-temperature turfgrass diseases