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The genetic variation of Norway spruce provenances from fourteen geographical regions were tested in the IPTNS−IUFRO 1964/68 experiment in Krynica. The genetic structure of seven isozyme systems coded by eleven loci was described. Parameters of genetic polymorphism i.e. the average number of alleles per locus and observed heterozygosity were 1.47 and 0.12, respectively. The spruces from Belarus were characterised by the highest genetic diversity, while the provenances from south−eastern Styria – the lowest. The values of Wright's inbreeding coefficient varied from –0.417 for the Romanian provenances to 0.223 for the provenances from 28th Krutzsch regions (Tyrol−Salzburg; Austria).
In this study the genetic structure of Istebna and Tarnawa plus trees was studied and polymorphism of twenty four provenances of spruce tested in a IPTNS−IUFRO 1964/68 site in Krynica representing selected regions of the species occurrence was analyzed. The genetic diversity was estimated with seven isoenzyme systems encoded in eleven loci. The highest genetic polymorphism was shown by plus trees of the Istebna and Tarnawa race and the lowest by spruce from IUFRO experiment. There was a statistically significant effect of origin on the mean number of alleles per locus. The origin of the analyzed trees had no effect on other parameters of genetic variability: the effective number of alleles per locus, observed and expected heterozygosity and Wright index.
In connection with the decline of spruce stands on the Krynica plots of IPTNS-IUFRO 1964/68, observed in the last decade and attributed to the so-called spiral disease, an attempt was made to determine whether the current health condition of trees is influenced by genotype (provenance). As shown by preliminary observations, the spruces differed in the degree of survival depending on provenance. The inventories of died or broken trees to be removed during the sanitary cutting, made in the years 2000, 2003, 2004 and 2008, yielded also information about the number of spruces that remained in the blocks of the experiment for each provenance and provenance region by Krutzsch (1968). Analysis of variance showed that genotype (provenance) has a statistically significant effect on the survival of trees. In the years 1999-2008, spruces from region 21 (Bohemian Forest) displayed the poorest survival rate in the conditions of the Beskid Sądecki Mts., while those from region 80 (Eastern Siberia) survived best.
The results of previous studies have shown high breeding values of Beskidian spruce. The aim of the study was to assess the genetic structure of seventeen Norway spruce provenances from the Beskidy Mts. tested in IPTNSIUFRO 1964/68 experiment in Krynica, which survived after massive wind damage on the plots. Polymorphism of five isozyme systems encoded in five loci was determined. The highest value of genetic diversity parameters: mean number of alleles per locus and observed heterozygosity was noted for progeny of spruce from the Eastern Beskidy Mts. (Na = 1.47, Ho = 0.15), and the lowest – for the provenance from the Western Beskidy Mts., Babia Góra massif and the Beskid Sądecki Mts. (Na = 1.27, Ho = 0.12). Mean genetic distance between analyzed spruce provenances was equal to 0.027.
The study aimed to determine the genetic variability in pitch pine (Pinus rigida Mill.) growing in the Niepołomice Forest (southern Poland). In the late nineteenth and early twentieth century, Adolf Cieślar of the Department of Forestry Research in Mariabrunn near Vienna, Austria established the experimental crops of pitch pine. During the study, 227 trees that grew in seven subunits were considered; an analysis of genetic polymorphism using the intersimple sequence repeats (ISSR) technique revealed that pitch pine is genetically variable. The average number of alleles at a given locus for all the pine trees was 1.649, while the effective number of alleles at the loci was 1.435. The value of expected heterozygosity was 0.254, while the percentage of polymorphic loci was 75.30%. The average genetic distance between the examined pines was 0.082. Principal coordinate analysis (PCoA) divided the examined pines into three groups, which was also confirmed by the structure-analysis results of the software STRUCTURE. The resulting division was mainly generated by the SR70 primer, which was indicated to be the primer that differentiated the examined populations of pitch pine. Affiliation of particular trees to selected groups was based on their occurrence in individual crops. This suggests a different origin of the seeds used to establish the research plots of pitch pine in the Niepołomice Forest.
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