Testing Romanian seed sources of Norway spruce (Picea abies): results on growth traits and survival at age 30

Abstract

Growth traits and survival rate were evaluated in two field trials consisting of 33 provenances (seed stands) spread across the entire natural distribution range of Norway spruce in Romania. Total tree height, diameter at breast height (DBH) and survival rate were measured at 30 years after planting. Both growth and adaptation traits show substantial genetic variation among the tested seed stands. The amplitude of variation depends markedly on trait and testing site. This fact suggests that the best performing seed stands for growth and adaptation traits at each testing site can be selected. Two groups of valuable populations, located in the North and East of Eastern Carpathians (Apuseni Mountains), were identified. Survival rate was negatively correlated with growth traits, the average values in the two field trials were 68% and 70%. By analyzing growth and adaptation traits together with stem and wood qualitative traits, the best performing populations will be considered as tested seed sources and the forest reproductive material they can provide will be recommended for use in the regions of provenance where the two field trials are located.