EFFECTS OF SEXUAL REPRODUCTION AT DIFFERENT LATITUDES ON PERFORMANCE OF THE PROGENY OF PICEA-ABIES

Controlled crosses of the same combinations were performed in a Norway spruce seed orchard in northern Finland and in 1 of 2 orchards in sou thern Finland. Seedlings from II family pairs were cultivated and cold acclimated in a phytotron together with control provenances and were frozen in artificial freezing tests at different temperatures. The see dlings from the crosses at the northern location were generally more f rost hardy than their full-sibs from the southern crosses and were als o taller. The controlled cross seedlings were less frost hardy than na tural stand seedlings originating from the same latitude as their pare nts. A close relationship was found between the hardiness of the contr ol provenances and their latitude. The results indicate that adaptive properties of Norway spruce seedlings to some extent depend on the cli matic conditions at the site where the reproduction is performed.