Acta 93.indd - Výzkumný ústav Silva Taroucy pro krajinu a okrasné ...

Table 2. Some genetic diversity parameters in three primeval populations of silver fir and in their corresponding managedcounterparts at the levels of adult trees and regenerants (Niektoré ukazovatele genetickej diverzity troch populácií jedle bielejv pralesoch a príslušných obhospodarovaných porastov jedle zistené na úrovni dospelých jedincov a regenerantov)Populations Sample size Polymor. loci N a± st. d. N e± st. d. H e± st. d.Badin – primeval stand, adult trees 68 0.78 1.92 ± 0.61 1.47 ± 0.51 0.250 ± 0.22Badin – primeval stand, regenerants 138 0.78 2.07 ± 0.73 1.39 ± 0.48 0.217 ± 0.20Badin – managed stand, adult trees 60 0.78 1.92 ± 0.61 1.40 ± 0.52 0.216 ± 0.22Badin – managed stand, regenerants 190 0.92 2.42 ± 0.64 1.43 ± 0.53 0.234 ± 0.20Dobroč – primeval stand, adult trees 63 0.57 1.71 ± 0.72 1.35 ± 0.54 0.179 ± 0.22Dobroč – primeval stand, regenerants 78 0.50 1.57 ± 0.64 1.27 ± 0.53 0.135 ± 0.20Dobroč – managed stand, adult trees 80 0.78 2.00 ± 0.67 1.38 ± 0.51 0.208 ± 0.20Dobroč – managed stand, regenerants 126 0.64 1.92 ± 0.82 1.35 ± 0.53 0.188 ± 0.21Stužica – primeval stand, adult trees 81 0.64 1.92 ± 0.82 1.47 ± 0.62 0.227 ± 0.24Stužica – primeval stand, regenerants 115 0.78 2.00 ± 0.67 1.36 ± 0.48 0.194 ± 0.21Stužica – managed stand, adult trees 58 0.71 2.00 ± 0.78 1.40 ± 0.52 0.210 ± 0.22Stužica – managed stand, regenerants 182 0.92 2.28 ± 0.61 1.43 ± 0.53 0.229 ± 0.22Palota – managed stand, adult trees 58 0.64 2.07 ± 0.91 1.55 ± 0.61 0.268 ± 0.24Palota – managed stand, regenerants 176 0.85 2.42 ± 0.75 1.44 ± 0.53 0.238 ± 0.22N a– number of observed alleles, N e– number of effective alleles, H e– expected heterozygositypopulations Badín and Stužica (0.250, 0.227) than in theirmanaged stands (0.216, 0.210). The reverse situation was foundin Dobroč showing higher level of expected heterozygosityin its managed rather than primeval population (0.208 vs0.179 in primeval stand). It is of interest to mention in thisconnection that the highest degree of expected heterozygositywas found in adult trees on the locality Palota (0.268) servingas a managed control to Stužica primeval population. At thelevel of adult trees and regenerated progenies, the formerharbour a higher degree of expected heterozygosity thancorresponding progenies. In particular it is true for all thethree primeval populations analyzed and for the managedpopulations Dobroč and Palota. Managed populations inBadín and Stužica were the only exceptions showing higherdegree of expected heterozygosity in regenerants.Based on analyzed isoenzyme diversity components,a dendrogram was constructed using standard geneticdistances and showing genetic differentiation betweenindividual populations of silver fir (Fig. 2). Their clusteringon the dendrogram reflected both geographic and preservedorigin or managed nature of the populations. The populationsfrom the locality Badín have accordingly been positionedin the upper part of a dendrogram (1–4), while those fromthe locality Stužica in the bottom (10–14). The populationsfrom Dobroč occupy intermediated position (5–8) exhibitinga higher genetic afinity towards populations in Stužica thanto those in Badín. The only exception was in this respect thepopulation of adult trees of Stužica primeval stand (9) whichhas been inserted rather atypically, e. g. between Badín andDobroč populations. It is apparent from a separation on thedendrogram that primeval and managed stands in Badín (1,3) and in Dobroč (5, 7) are profoundly differentiated fromeach other. A common cluster of the managed populations inStužica and those situated 40 km away in Palota may be takenas an evidence supporting their common origin. Contrastingfeature of the illustrated clustering is a short genetic distance72ascertained between adult trees and regenerants in Dobroč (5,6) and extremely large distance between the analogous groupsof trees in Stužica (9, 10) exceeding even the genetic distancesbetween widely separated populations of the species fromdifferent geographic regions of the country. This aspect ofsilver fir genetic differentiation needs to be analyzed further.DISCUSSIONIn Central Europe the silver fir is an integral part of the socalled„Carpatho-Herzynic mixture“ along with Europeanbeach and Norway spruce (Korpeľ, 1995). The „mixture“represents the most productive forest ecosystem whichharbours incomparatively greater biodiversity than otherecosystems in the region. According to Paule et al. (2001)the human activity, mainly forest management and industrialpollution, contributed in a variable extent to the narrowingof genetic variability of individual species of the ecosystemaffecting negatively its productivity. Only some of the testedmarkers corroborate this conclusion. At the level of cpDNA,it was the hyplotype B which indicates a slight decrease ofits proportion in adult trees of managed populations. Thehaplotype A exhibited an opposite tendency. The same is trueof the isoenzyme polymorphic loci and the observed alleleswhose proportion and number were found to be higher inadult trees of managed rather than in the primeval populations.The most convincing evidence about the negative impactof managing on silver fir populations was provided by thenumber of effective alleles and expected heterozygosity. As theprincipal components of genetic diversity these parameterswere of higher values in adult trees of the primeval populationsin Badín and Stužica than in their managed counterparts.However, no generalization of the kind can be made asevidenced by the opposite genetic diversity figure observed in