Genetic Variation in Provenance-Progeny Trials of Cupre-ssus sempervirens in Türkiye

In this study, the genetic and phenotypic relations among tree height, diameter at breast height and survival at 18 years of age were investigated in Mediterranean cypress ( Cupressus sempervirens L. var. horizontalis (Mill.) Gordon) provenance-progeny trials established in two locations in southern Türkiye. It was found that the variation among families within one provenance was higher than among different provenances. At the joint analysis, the narrow-sense heritability (hi2) was 0.36 for height, and 0.24 for diameter. Family mean heritability (hf2) was 0.78 for height, while it was 0.53 for diameter. Diameter showed higher (13.98%) genetic diversity than height (12.71%). Genetic correlation between traits was high (0.84). According to the breeding values of the families estimated by the BLUP method, when the best 50 families by two traits are selected separately, 12.5% genetic gain in terms of height and 13.2% in terms of diameter can be achieved. In the selection of the best 30 families, the estimated genetic gain calculated was 15.2% for height and 16.3% for diameter.