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ŠUMARSKI LIST 11-12/2019 str. 38     <-- 38 -->        PDF

Earlier studies on variation in morphological and genetic characters have revealed the existence of considerable variation in oriental spruce (Atalay 1984; Goncharenko et al. 1996; Turna and Yahyaoğlu 2002; Turna 2004; Temel 2010). However, there is not much study showing genetic variation by using different enzyme systems to represent the natural distribution areas of this species.
Expected and observed heterozygosities allow the most accurate estimation of the genetic variation level within populations. According to the results of the present study, it was determined that the mean observed heterozygosity (Ho) value was 0.154. In a study conducted in 12 populations using two enzyme system for P. orientalis in Turkey, mean expected heterozygosity per population varied from 0.128 to 0.463, with an average of 0.280 (Turna and Yahyaoğlu 2002). Serbian spruce (Picea omorika (Panc.) Purk.), having isolated distribution range like Picea orientalis, exhibited considerable variation in terms of both heterozygosity and gene diversity among populations. Observed heterozygosities ranged from 0.018 to 0.132, whereas expected heterozygosities varied from 0.017 to 0.096 (Ballian et al. 2006). In a research made in the populations of Picea abies, observed heterozygosity ranged from 0.136 to 0.173, with the mean of 0.158 in Carpathian region (Korshikov and Privalikhin 2007). Another study was conducted for Norway spruce distributed in Romania. According to this, expected heterozygosity (He=0.115) was similar to the average value obtained in 70 populations from Europe natural range of the species (Lagercrantz and Ryman, 1990; Radu et al. 2014). While expected heterozygosity was 0.156 in a study conducted in the same species in Poland, expected and observed heterozygosity were determined as 0.186 and 0.185, respectively, in a study conducted in Latvia (Goncharenko et al. 1995; Lewandowski and Burczyk 2002). Ballian et al. (2009) stated that observed heterozygosity in the populations of P. abies ranged from 0.19 to 0.22 in Slovenia and Bosnia and Herzegovina, on the extreme sites (for realistic data from Bosnia and Herzegovina, the author should consult the proposed literature). It is clearly understandable that there are similarities between the previous researches related to Picea genus and the present study. Unlike this situation, Gömöry (1992), in the study for P. abies in Poland, reported that expected and observed heterozygosity were 0.306 and 0.275, respectively. In this study for oriental spruce, the grand mean of Ho=0.154 showed the smaller average heterozygosity than the reported studies for Norway spruce including Ho=22.6 % (Müller-Starck 1995), Ho=25.2 % (Konnert and Franke 1990; Konnert 1991), Ho=22.2 % (Löchelt and Franke 1993). In addition, observed heterozygosity was found as 14.7 % in a study in Austria (Geburek 1999).
The number of alleles per locus (AL=1.74) obtained from the present study conducted for Picea orientalis was higher than other Norway spruce populations studied in Romanian Carpathians region (AL=1.21) (Radu et al. 2014). While AL value (1.58) obtained for Picea abies in another study (Lagercrantz and Ryman 1990) was close to the value that we obtained in our study, AL=1.45 value obtained for Picea asperata was lower (Luo et al. 2005).  Krutovskii and Bergmann (1995) found that this value occurred as 2.4 for Picea obovata in Kazakhstan and Siberia. In different studies made for P. abies, the number of alleles per locus was determined as 2.17 in Poland (Lewandowski and Burczyk 2002), as 2.2 in Austria (Geburek 1999), as 2.26 in Latvia (Goncharenko et al. 1995), as 2.50, 2.80, 2.90, 2.90 and 2.80 in Germany, Sweden, Byelorussia, Ukraine and Russia, respectively (Krutovskii and Bergmann 1995), as 2.59-2.71 in the Mountain of Igman (Ballian et al. 2007a), as 2.06 and 3.38 in Slovenia and Bosnia and Herzegovina, respectively (Ballian et al. 2009), and as 3.55 in Ukrainian Carpathians (Korshikov and Privalikhin 2007). As can be seen from the results, these values are higher than the number of alleles per locus obtained for P. orientalis in this study.
According to results of a study conducted for P. asperata in China, the sampled populations were characterized by low genetic diversity (mean He=0.096) and a low level of inbreeding (mean Fis=0.005). In addition, the expected heterozygosities (He) and observed heterozygosities (Ho) were relatively low and ranged from 0.066 to 0.131, and from 0.059 to 0.141, with an average of 0.096 and 0.094, respectively (Luo et al. 2005).  In a study carried out for P. abies in Poland, a relatively low allozyme differentiation was determined among populations from north-eastern and southern Poland (mean genetic distance D=0.005). According to the results, historical events and extensive gene flow played a significant role in the distribution of the observed allozyme differentiation of the species in Poland (Lewandowski and Burczyk 2002). In another study conducted by Geburek (1999) regarding P. abies, while the genetic diversity was 1.18 in Austria, this varied from 1.23 to 1.28 in Slovenia and Bosnia and Herzegovina, on the extreme sites. (for realistic data from Bosnia and Herzegovina, the author should consult the proposed literature) In the study conducted in Latvia, the genetic distance among the populations ranged between 0.003 and 0.012. When the results of the study were evaluated, there were a very low differentiation and a close genetic relationship among the populations in Latvian (Goncharenko et al. 1995).
While the highest value in terms of Vgam (18.077) was determined in Provenance No. 2 (Torul-Örümcek), the lowest one was obtained as 8.656 in Provenance No. 4 (Ordu-Çambaºı). The arithmetic grand mean related to this value was 12.877. Oriental spruce has a local and limited natural distribution for both Turkey and the world. Therefore,