Performance in freezing tests and field experiments of full-sib families of Pinussylvestris (L.)

Abstract

Full-sib families from plus trees of Pinussylvestris (L.) were tested in four 10-year field experiments and three 1-year experiments. Survival and height were assessed in the field experiments and plant height, dry matter content, and damage following artificial freeze testing during the hardening process in the 1-year experiments. Positive correlations between pairs of field experiments were found for breeding values for 10-year survival (rmean = +0.71) and 10-year height (rmean = +0.38). Positive correlations were also obtained between survival and height within field experiments. Breeding values for 10-year field survival and height were not correlated with the latitude of origin. Positive correlations were found between field mortality and both damage after freeze testing (0.61 < r < 0.85) and plant height (r = 0.75) for the 1-year-old seedlings. Results indicated that a low degree of damage after freeze testing of 1-year-old progenies is a better predictor of field survival than is northern geographical origin when establishing seed orchards of P. sylvestris for harsh areas in north Sweden.