Evaluation of Turfgrass Crown Membrane Health in Response to Ice Stress and Management Practices of Creeping Bentgrass and Annual Bluegrass Putting Green Species.

Creeping bentgrass and annual bluegrass are two highly managed putting green species that are sensitive to ice cover and winter damage. The objectives of this study were to evaluate the effects of various chemical treatments on crown fatty acid ratios and carbohydrate content under ice cover stress and correlate those results with respiratory gas accumulation. Separate creeping bentgrass and annual bluegrass field plots were treated in late summer through fall with: Civitas, mefluidide, propiconazole, or trinexapac ethyl, in preparation for turf plants to undergo acclimation to winter conditions. Turfgrass plugs were then taken in late fall from each plot and transferred to an environmentally controlled low temperature growth chamber (-4^oC) where they underwent ice cover or no ice cover treatments. Turfgrass plugs were taken out of the low temperature growth chamber after 0, 20, 40, 60 100 and 120 days where destructive sampling occurred. One half of the plugs went towards further analysis while the other half went towards a regrowth assay. Civitas treated plugs had the greatest regrow after ice and cold temperature treatments while trinexapac ethyl treated plugs had the least amount of regrowth when compared to the control in annual bluegrass. Crown membrane fatty acid profiles and carbohydrate content associated with chemical treatments will be discussed.