Genetic variation in six natural populations of Scots pine (Pinus sylvestris L.) was determined with isoenzyme analyses. For this purpose, haploid female gametophytes of seeds and horizontal starch gel electrophoresis technique were used. A total of 17 loci and 58 alleles were observed in studying 10 enzyme systems. The average proportion of polymorphic loci for populations ranged from 58.8% to 70.6%. The average number of alleles per locus per population was 2.65. The mean estimated expected heterozygosity (He) of populations was 0.294. A rather high proportion of genetic diversity (96.4%) was due to within-population variation and the remaining (3.6%) was due to variation among populations. The level of gene flow (Nem) was found to be 6.69 per generation. Nei's genetic distance coefficient ranged from 0.006 to 0.027 (mean 0.017) among all possible population pairs. The mean value of Nei's genetic distance is similar to the values reported for other European Scots pine populations. The low mean value of Nei's genetic distance among populations is enough to explain low interpopulation variation. According to genetic variation parameters, three out of six populations (Akdagmadeni-Yozgat, Refahiye-Erzincan and Vezirkopru-Samsun) appear to be preferable populations for genetic conservation and forest tree breeding programs.

Introduction Sunflower (Helianthus annuus L.) is one of the most significant oilseed crops in Europe, mainly grown for its edible oil and confectionery uses. Turkey takes part in the second group of sunflower producer countries (totally 27%) with China,

Turkish Red Pine (Pinus brutia Ten.) is an important forest tree species in Turkey for various economic and ecological reasons. In this study, nine RAPD (Randomly Amplified Polymorphic DNA) primers were used to determine genetic variation within and among populations of P. brutia located at the Duzlercami common-garden test site. This site was established in 1979 and includes six natural populations of P. brutia from two altitudinal transects extending from the coast to higher elevations in the Antalya region of Turkey. A total of 32 polymorphic RAPD loci were found in the analyzed six populations. The mean proportion of polymorphic loci among population samples equals 100%, mean number of alleles for each locus = 2.0, effective allele number = 1.71, Shannon's information index = 0.58, and mean Nei (1973)'s gene diversity value = 0.4. According to G ST results, a high proportion of genetic diversity (95-99%) is found within populations. A relatively high genetic differentiation was found among altitudinal population pairs in both transect. Also, data on quantitative traits (total height and/or diameter) at different ages (13, 17, 30 years) were compared with molecular data. There are similarities between the results obtained from RAPD markers and those obtained from the quantitative traits. The differentiation in quantitative traits appears to be due to local adaptation of populations. Data suggest that priority should be given to the selection of material based on geographic origin along the altitudinal gradients of P. brutia populations to conserve the genetic resource of species.

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Pollen contamination is one of the important factors affecting the yield, adaptability, and genetic quality of the seed produced from seed orchards in forest tree breeding programs. Incoming pollen from the forests surrounding the seed orchard is a major concern in tree breeding because it contributes to losses in the expected genetic gains from seed orchard crops. The genetic variation and the level of pollen contamination in a 16-year-old Pinus brutia Ten. first-generation clonal seed orchard was studied using chloroplast microsatellite markers (cpSSRs). In total, 23 alleles and 36 unique allelic combinations (haplotypes) were detected based on the 6 cpSSR loci analyzed. The haplotypic diversity of the clones in the seed orchard was found to be 0.849. Out of 300 embryos analyzed, 87 were not compatible with any male parent within the seed orchard. Thus, 29% of the embryos were sired by pollen sources outside the orchard (i.e. apparent contamination). Microsatellite-based analysis revealed that the estimated contamination rate was 39.3%. Background pollination at this level will cause losses of 20% in the expected genetic gains. Our findings are valuable for the assessment of the intended seed orchard function, i.e. provision of genetically improved seed. It may be worthwhile to use pollen management strategies like strobilus stimulation, controlled pollination, and supplemental mass pollination to decrease pollen contamination and increase the genetic quality of the seeds produced.