GENETIC-STRUCTURE OF MARGINALLY LOCATED PINUS-NIGRA VAR PALLASIANA POPULATIONS IN CENTRAL TURKEY

To determine the genetic structure of marginally located populations o f Pinus nigra var pallasiana, seedlings of open pollinated families fr om 7 populations were raised in Kizilcahamam nursery near Ankara for 2 years. Seed weight (SW) and cone weight (CW) for families, number of cotyledon per seedling (GOT), timing of bud set in 1990 (BS90) and in 1991 (BS91), bud burst timing of seedlings in 1991 (BB91), height grow th in 1991 (HT90) and final height growth in 1991 (HT91) and final dia meter growth of seedlings (DM91) were recorded. Among the traits studi ed, the component of genetic variation attributed to regions (ranging from 0% to 5.7% of the total variation) and populations (ranging from 0% to 9%) made up very small portion of the total genetic variation wh ile variation among the families within population was very high (rang ing from 11.5% to 91.5%). The estimated family heritabilities were mod erately high for the most of the traits, ranging from 0.28 for BB91 to 0.98 for SW. Correlations between seedling traits and topographic var iables were not significant, suggesting that effects of aspect, slope and altitude on genetic differentiation of population are minor. In ge neral, phenotypic and genetic correlations between seedling traits wer e generally the same sign and magnitude, however, genetic correlations between height growth and bud set timing were strongly negative (-0.5 4). It was concluded that the marginal populations of Anatolian black pine maintain a large within population genetic variation in order to he able to adapt to the mosaics of micro-environments that exists in t hese locations. The implications of the findings in the study in terms of tree improvement and genetic adaptation mechanisms in the species are discussed in detail.