Cold hardiness research on agricultural and horticultural crops in Finland

This paper represents an overview of cold hardiness research conducted on a gricultural and horticultural crops, as well as on amenity plants in Finlan d. Inadequate freezing tolerance and/or winter hardiness often prevents int roduction of new species and cultivars to Finland. Field observations on wi nter hardiness and more recently the results from laboratory freezing tests , have assisted breeders to select hardy genotypes. Research approaches for agricultural crops have evolved from observations on winter and frost dama ge to studies on molecular mechanisms of cold acclimation and freezing inju ry. The results of experiments on survival of winter cereals, grasses and c lovers and frost tolerance of potato and turnip rape are discussed. The stu dies conducted on horticultural crops, including apple, strawberry, raspber ry, currants, blueberry, sea buckthorn, perennial herbs as well as on ornam ental trees and shrubs have included field evaluations of cultivars, or sel ections for winter hardiness, and studies on the effects of cultural manage ment practices on winter survival. During the last decade detailed studies including controlled freezing tests have provided tools to assist in explan ation of the underlying mechanisms of cold hardiness also in horticultural plants.