Within‐population variation in autumn frost hardiness and its relationship to bud‐set and height growth in Picea abies

Abstract

Artificial freezing tests were performed with two sets of 12 full‐sib families of Picea abies. Each set was selected from a complete diallel cross performed within a natural population. Significant differences in autumn frost hardiness were observed between the two populations, which originate from the same altitude and longitude approximately 60 km apart. Substantial variation in frost hardiness was observed within both populations. Significant pheno‐typic correlations at the individual level were found between freezing injury and the two traits terminal bud‐set and height growth year one. However, no significant relationships were present between freezing injury and bud‐set at the family level, indicating that bud‐set cannot be used to predict autumn frost hardiness for families.

Key words:

• Picea abies
• freezing tests
• autumn frost hardiness
• bud‐set
• phenotypic correlations