Cold tolerances in plants

Purified antifreeze polypeptides isolated from the extracellular spaces between the cells of winter rye where said polypeptides control ice crystal growth in the intercellular plant spaces, such control of ice crystal growth providing a degree of plant frost tolerance,

• said purified polypeptides having the following properties of:
• i) being developed in extracellular spaces between plant cells of frost tolerant winter rye plant leaves by low temperature induction of frost tolerant winter rye plant to produce said polypeptides;
• ii) being isolated from said extracellular spaces and purified;
• and
• iii) being selected from a group of purified antifreeze polypeptides consisting of polypeptides having respectively apparent molecular weights as determined by SDS-PAGE Gel separation under non-reducing conditions, of about 11 kD, about 15 kD, about 23 kD, about 27 kD, about 31 kD, about 32 kD, about 33 kD, about 93 to 99 kD and about 161 kD.