Factors Affecting the Cold Survival of Winter Cereals

Several parameters affecting cold tolerance of winter cereals in artificial freeze tests were examined. Supercooling followed by freezing resulted in death occurring at a higher temperature than when freezing was initiated just below 0 C. The cold tolerance of fully acclimated crowns of winter wheat and a winter rye were reduced an average of 5 C after two thawing and freezing cycles. The duration of freezing in artificial freeze tests has a significant effect on the LD50 of winter cereals. Rapid thawing (2–4 C/min) resulted in death occurring at a higher temperature than slow thawing (0.5–2 C/h).