Freezing resistance of strawberry flowers from `Benton', `Honeoye', `Hood', `Puget Beauty', `Rainier', `Redcrest', `Shuksan', `Sumas', `Totem', and WSU 1988 was measured in laboratory tests. Flowers with approximately 13 mm of pedicel attached were placed in test tubes containing 2 ml DI water. Tubes were immersed in an ethylene glycol bath, the temperature lowered to -1°C, and the flowers inoculated with crushed ice. The temperature was lowered to -1.5°C, held overnight then lowered 0.5°C every 2 hours. Samples were removed at 0.5°C intervals, thawed overnight at approximately 3°C and incubated 24 hours at room temperature and 100% RH. Freeze damage of styles and receptacle was determined by visual browning. Flower survival with no visible damage averaged 27% at -1.5, 13% at -2.0, 7% at -2.5, and 4% at -3.0°C. There was clonal variation in flower survival: 56% of `Hood' flowers survived -1.5 and 45% survived -2.0 while 5% of `Redcrest' and `Sumas' flowers survived these temperatures. Results seem to indicate that strawberry flower freeze resistance was due to freezing avoidance via supercooling.
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