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The prevention of transmissible spongiform encephalopathy (TSE) in humans and animals has become an important element of safe food production. Part of the studies connected with this problem concentrate on the search for potential markers of the susceptibility or resistance to bovine spongiform encephalopathy (BSE). The present report presents a characteristic of the bovine prion protein (PRNP) gene polymorphism within the population of european bison and two endemic cattle breeds – Polish Red (PR) and Polish Whitebacked (PWb), the latter two included in a genetic resources conservation programme.European bison appeared monomorphic as regards PRNP what was reflected by the presence of only one genotype – PRNP 6/6. In the northern (lowland) subpopulation of PR the frequency of PRNP 6/6 and PRNP 6/5 genotypes was 0.926 and 0.074, respectively. In the PR southern (sub-montaneous) subpopulation the share of PRNP 6/5 and PRNP 5/5 was 0.214 and 0.049. In the PWb cattle the frequency of PRNP 6/6 was 0.628, that of PRNP 6/5 – 0.321, and of PRNP 5/5 – 0.051.
Peat-bog pine Pinus uliginosa Neumann has become extinct or rare in many parts of Europe. We have investigated the levels of genetic variation and inbreeding in seeds collected from a highly endangered reserve of this species in Poland, using allozymes as genetic markers. Generally, a high level of genetic variation was observed. The mean expected heterozygosity was 0.376, while average (Na) and effective (Ne) numbers of alleles per locus were 2.45 and 1.67, respectively. Nevertheless, we have detected relatively low levels of outcrossing, and potential biparental inbreeding. The population-wide multilocus outcrossing rate was estimated to be 0.706 (±0.091), while the minimum variance mean of single-locus estimates was distinctly lower (ts=0.611). The estimates of outcrossing calculated for individual trees ranged widely from 0.051 to 1.017, indicating the complexity of outcrossing patterns. The investigated population of P. uliginasa from Węgliniec is small and surrounded by extensive forest stands of P. sylvestris. Our three-year records of phenological observations demonstrated that flowering periods for P. uliginosa and P. sylvestris overlap, allowing for cross-pollination. The possibility of P. uliginosa pollination by P. sylvestris creates a potential danger of genetic erosion of the P. uliginosa gene pool. Nonetheless, based on a species specific cpDNA marker we have found that among 533 seedlings of P. uliginosa there were only six seedlings carrying cpDNA marker specific for P. sylvestris, indicating that such hybridization seems to be rare.
The paper describes the measures adopted by the Czech State Forests for the conservation and reproduction of the Norway spruce gene pool in the Moravian-Silesian Beskid Mts. In addition to the assurance of natural regeneration in genetically valuable stands and the use of high-quality autochthonous stands as seed sources for artificial regeneration, the measures include selection of plus-trees, establishment of seed orchards, seed stands and clone archives, and identification of gene pools. Seeds of the most valuable regional populations are deposited in a seed bank.
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