Protein changes during heat stress in three Kentucky bluegrass cultivars differing in heat tolerance

High temperature was applied to Ever Glade, Nassau and Kenblue, which are the three common bluegrass varieties in Northern regions, and the result indicated as below: under the high temperature of 38益/30益(day/night), Ever Glade maintained a relatively better turf quality and higher chlorophyll content compared to the other two varieties, placing Nassau in the middle in terms of performances and Kenblue the last; The content of cytoplasmic and membrane proteins of the three varieties all declined, but Ever Glade's content was higher than that of Nassau and Kenblue on the 28th day. It was detected, with the analysis of SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), that cytoplasm (54, 66 and 85 kDa) and membranes(18, 24, 57 and 72 kDa) appeared the earliest in Ever Glade. The result suggested that heat-resistant bluegrass variety produced a higher content of protein and a faster HSPs (heat shock proteins) synthesis under heat stress.