Proteomic Profile Associated with Heat Tolerance in Fine Fescue.

Heat causes premature leaf senescence in cool-season grass species. Proteins, which could play an important role in the physiological and metabolic pathway of the cells, undergo significant changes at high temperature. The purpose of this study is to identify proteins associated with leaf senescence during heat treatment. Three cultivars (Longfellow, Predator and Reliant IV) of fine fescue which were previously shown different heat tolerance were exposed to high temperature at 38/33 °C (day/night temperature) and optimal temperature at 22/18 °C as control in a temperature-controlled growth chamber. To assess the progress of heat induced senescence, chlorophyll content, membrane stability, photochemical efficiency and overall turf quality were measured after 7d, 14d, 21d and 28d. The profiling of soluble proteins, which were analyzed using two-dimensional gel electrophoresis, changed during heat treatment, and the changes of the profiling are different among different cultivars. The result suggested the increased expression of proteins involving in redox homeostasis, cytoskeleton composition, glycolysis, photorespiration and chaperone functions. The different increased expression of proteins may contribute to the heat tolerance variation.