Genetic variation in Pinus brutia Ten. seed stands and seed orchards for growth, stem form and crown characteristics

In this study, some adaptive traits (growth, stem, branching and crown characteristics) in a seven-year old plantation of Turkish red pine (Pinus brutia Ten.) were studied in 2008. The experiment was established by using 1+0 bare-root seedlings from 5 seed stands and 5 seed orchards from the same origins in 2001. Randomized block design with three replications was used in the field. There were a total of 100 families, 10 from each of these 10 populations were used in the experiment. Each family was represented with 10 seedlings in each replication. Populations and families within each population were significantly different for all traits both in the seed stands and in the seed orchards. The percent of genetic variation caused by population was considerable except for branch length ranging from 0.19 to 18.28% especially in the seed stands. Variance components due to families in the seed orchards were in general higher than those in the seed stands. Individual heritabilities varied in 0.45 – 0.90 range. Family heritabilities ranged from 0.76 to 0.88. These results indicated that combined population, family and within family selection for studied traits would result in considerable gain in this species.   Key words: Genetic variation, heritability, Pinus brutia Ten., seed stand, seed orchard.