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

To determine the genetic structure of marginally located populations of Pinus nigra var pallasiana, seedlings of open pollinated families from 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 growth in 1991 (HT90) and final height growth in 1991 (HT91) and final diameter growth of seedlings (DM91) were recorded. Among the traits studied, 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 while variation among the families within population was very high (ranging from 11.5% to 91.5%). The estimated family heritabilities were moderately high for the most of the traits, ranging from 0.28 for BB91 to 0.98 for SW. Correlations between seedling traits and topographic variables were not significant, suggesting that effects of aspect, slope and altitude on genetic differentiation of population are minor. In general, phenotypic and genetic correlations between seedling traits were generally the same sign and magnitude, however, genetic correlations between height growth and bud set timing were strongly negative (-0.54)

Genetic variation in wood specific gravity of half-sib families of Pinus nigra subsp pallasiana tested at the juvenile stage: Implications for early selection

Seeds from 7 populations (total of 281 half-sib families, progeny test) and 35 seed stands (provenance test) representing natural range of Anatolian black pine (Pinus nigra subsp. pallasiana) were sown in a forest nursery in Ankara in 1990 and raised until age 3. Stem wood specific gravity (WSG) of all seedlings was determined at age of 3. The results of this study indicated that WSG did not vary significantly neither among the 7 populations (ranging from 0.41 to 0.42) nor among 35 seed stands (ranging from 0.37 to 0.46). Differences between half sib families for WSG were, however, statistically significant. Estimated family heritablity was moderately high (0.38) Genetic correlations between seedling growth traits and WSG were low, but consistently negative. The families with better height and diameter growth had lower WSG values. Also families with late budset and budburst dates in 1991 had lower WSG values. Seedlings originating from northern latitudes had lower WSG than those from southern latitudes. From the results of the study, it seems that early selection of families for WSG (indirect selection for WSG at mature age) would be possible and substantial genetic gain in WSG could be achieved if the selection based on a multi-trait index selection by giving appropriate weights to WSG and other traits. Further implications of early selection for WSG in Anatolian black pine are also discussed in the paper