Measuring freezing tolerance: survival and regrowth assays.

Screening plants for freezing tolerance under tightly controlled conditions is an invaluable technique for studying freezing tolerance and selecting for improved winterhardiness. Artificial freezing tests of cereal plants historically have used isolated crown and stem tissue prepared by "removing all plant parts 3 cm above and 0.5 cm below the crown tissue" (Fowler et al., Crop Sci 21:896-901, 1981). Here, we describe a method of conducting freezing tolerance tests using intact plants grown in small horticultural containers, including suggested methods for collecting and analyzing the data.