Reactions of strawberry plants to long-term freezing and alternate freezing and thawing

Summary

The study was conducted in two experiments, one examining the effects of alternate freezing and thawing at –12?C for 2 h and +6#x02DA;C for 24 h, and the other examining the effects of permanent freezing for 1 or 15 d at+12?C. In both experiments the plants were grown in the pre-fruiting period at a coastal or a continental location in Norway. The freezing injury increased the higher the stress, indicated by reduced growth, fruit size and yield.It was shown that ‘Korona’ was the most hardy cultivar at a short period of freezing stress and at alternate freezing and thawing, while ‘Senga Sengana’ was more freezing tolerant at long-term permanent freezing than ‘Bounty’ and ‘Korona.’ In general the results indicate that the plants induce freezing tolerance according to some factor of origin, since plants grown in the continental climate were better able to survive long-termpermanent freezing than plants grown in a coastal climate, and plants grown in a coastal climate were better able to survive alternate freezing and thawing than plants grown in a continental climate.