Although the results of the experiments demonstrating that
transgenic Arabidopsis expressing apoplastic DAFP-1 froze at signif-
icantly lower temperatures than wild-type plants is encouraging,
a degree of freeze protection greater than 1–3 ◦ C will be neces-
sary to have a major impact on the ability of plants to survive a
significant frost event. The small amount of freeze avoidance
(1–3 ◦ C) achieved was attributed primarily to the low level of ther-
mal hysteresis activity accomplished,