"One aspect of the golf industry is turfgrass management. Annual bluegrass (Poa annua L.) is a golf course turfgrass species, often in a mixed stand with creeping bentgrass (Agrostis stolonifera). Many golf courses in the transition zone and north can be susceptible to ice or freeze injury to golf course putting greens. Annual bluegrass is more susceptible to ice cover damage than creeping bentgrass. In this thesis we aimed to evaluate mechanisms which could alleviate ice cover stress to annual bluegrass through exogeneous applications of chemicals prior to ice cover through fatty acid analysis of annual bluegrass crown tissue. We also intend to examine the role of the plant growth hormone, ethylene, in annual bluegrass and its effects on ice cover survival. Applications of fungicides or plant growth regulators to golf course putting greens are common turfgrass management tools. Trinexapac-ethyl, Civitas, paclobutrazol, and propiconazole are commonly applied to golf course putting greens. Applications of trinexapac-ethyl decreased unsaturated fatty acids while increasing saturated fatty acids ratios in crown tissue of annual bluegrass while Civitas increased unsaturated fatty acids and decreased saturated fatty acids. This was correlated to ice cover recovery with Civitas increasing recovery and trinexapac ethyl decreasing recovery after ice cover. The gaseous hormone ethylene was then examined to determine its role in changes to fatty acid ratios of annual bluegrass under ice cover. Applications of effective ethylene chemicals decreased unsaturated fatty acid ratios while increasing saturated fatty acid ratios."--Pages ii-iii.
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