Scientific publications

Growth and survival of 123 grafted and half-sib Scots pine (Pinus sylvestris L.) progenies have been investigated in a 1st generation seed orchard and progeny tests of various ages. It was found that during the first decade after planting the survival rate of the progeny tests was going slightly down, with a simultaneous decrease in the share of progenies superior to the control, and in the degree of superiority (height difference). We observed a moderate statistically significant correlation between the heights of maternal clones and their half-sib progenies, with its positive trend (from r = 0.28 in 2014 up to r = 0.33 in 2018) during the entire study period. Older progeny tests (30 years old) showed a moderate significant correlation (r = 0.36) in the ratio of stem faults (forked, multistem) between clones and half-sib progenies. It was confirmed that selection based on growth rate should have the highest priority for Scots pine plus trees provided that the habit and seed productivity of their clones are taken into account. The results reported here testify to the statement that reliable preliminary assessments of half-sib families can be obtained starting at the age of 7, with the tests lasting 25–30 years at maximum. As a result of the breeding and selection assessment, a set of 20 plus trees (clones) had been formed fulfilling minimum requirements for an advanced-value seed orchard of the I,5 generation.