DIGITALNA ARHIVA ŠUMARSKOG LISTA
prilagođeno pretraživanje po punom tekstu
|ŠUMARSKI LIST 1-2/2013 str. 30 <-- 30 --> PDF|
Homozygous and heterozygous types that are much more frequent in the Vrhovo sample than in the Kozarje sample are: Idh-A33 (80 % vs. 56 %), Aco-B33 (80 % vs. 60 %), 6-Pgdh-B22 (90 % vs. 72 %), Pghd-A24 (44 % vs. 18 %), Pgdh-C14 (34 % vs. 20 %) and Mdh-C12 (50 % vs. 38 %). Heterozygous or homozygous types much more frequent in the Kozarje sample than in the Vrhovo sample are: Idh-A23 (38 % vs. 16 %), Aco-A23 (36 % vs. 16 %), 6-Pgdh-B12 (24 % vs. 8 %), Mdh-B34 (26 % vs. 12 %), 6-Pgdh-C15 (12 % vs. 2 %) and 6-Pghd-A22 (78 % vs. 50 %). Remarkable differences in allelic and genotypic frequencies were observed at gene locus Skdh-A. The allele A4 and heterozygous genotype A34 are stand-dependent. It was found at frequencies of 6 % and 12 % in the lower elevated Vrhovo stand, respectively, but not in the higher elevated Kozarje stand.
At 16 polymorphic enzyme gene loci, 43 allelic variants (Mmax) were found in two populations, which correspond to 2.69 alleles per locus (Table 2). The mean numbers of alleles per locus (A/L) were 2.50 at Vrhovo and 2.56 at Kozarje population, which is equivalent to a ratio of 1:1.02. The average values of the effective number of alleles per locus (ν) range from 1.31 (Vrhovo) to 1.34 (Kozarje) and correspond to a ratio of 1:1.05. The numbers of genetic variants of the 16 loci gametic types that the group of 50 sample trees in the populations (vgam) could have produced ranges from 104 (Vrhovo) to 157 (Kozarje) and corresponds to a ratio of 1:1.51. Although the calculated values (vgam) have only an indicative character, this comparison suggests greater potential of the group of beech trees at the Kozarje site than that of the group of beech trees at the Vrhovo site for the production of genetically different gametes, which will be subject to genetic variation in new generations.
The average value of observed heterozygosities (Ho) for the 16 loci gene pool are vary between 23.5 % in the group of trees from Vrhovo to 25.1 % in the Kozarje group of trees, which corresponds to a ratio of 1:1.06. As shown in Table 3, the Ho values are not uniform. The level of observed heterozygosity explicitly differs between the test populations from Vrhovo and Kozarje at 5 loci namely at Aco-B (20 % vs. 38 %), Idh-A (16 % vs. 38 %), Mdh-C (50 % vs. 38 %), 6-Pgdh-A (44 % vs. 20 %) and 6-Pgdh-B (8 % vs. 24 %). The mean of Hc values for two populations is 84.1 %. As Hc values are independent of the underlying allele frequencies, the calculated mean indicated to a slightly lack of heterozygotes as compared to the maximum attainable value which is equal to 100 %. The average levels of genetic (allele) differentiation δT in the sampled populations of beech range from 23.7 % (Vrhovo) to 25.8 % (Kozarje), which