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Abstrakt

Abstract RAPD analysis was applied to assess the degree of DNA polymorphism in A. fistulosum calli of high chromosomal instability. Nineteen of 24 randomly selected RAPD primers revealed scorable polymorphism between calli and seeds (reference material). Polymorphic band frequency was 55/237 in seeds and 36/233 in calli; variability on the DNA level was thus lower in calli than in seeds (15.4% vs. 23.2% of band positions). UPGMA analysis of Jaccard's coefficients confirmed the genetic similarity of the analyzed cultures. The most distinctive DNA changes in calli involved coincident loss of original bands or the appearance of novel bands. Seven such changes (4 losses, 3 gains) were observed. Our results suggest that changes on the chromosomal level and on the DNA level occurred independently of each other and that different callus lines underwent similar genetic changes during culture, presumably due to strong selection pressure effected by standard in vitro conditions.
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Abstrakt

Holoparasitic genera within the family Orobanchaceae are characterized by greatly reduced vegetative organs; therefore, molecular analysis has proved to be a useful tool in solving taxonomic problems in this family. For this purpose, we studied all species of the genera Orobanche and Phelipanche occurring in Central Europe, specifically in Poland, the Czech Republic, Slovakia, and Austria, supplemented by samples mainly from Spain, France, Germany, and Ukraine. They were investigated using nuclear sequences (ITS region) and a plastid trnLtrnF region. The aim of this study was to examine phylogenetic relationships within Orobanche and Phelipanche from Central Europe; we focused on problematic species and aggregates, recent taxonomic changes in these (rank and secondary ranks), and host ranges. The most interesting results concern the exlusion of O. mayeri from O. alsatica aggr. Additionally, following the rules of traditional taxonomy, the correct names and types of some secondary ranks are given and, as a result of this, a new combination below the Phelipanche genus is made (P. sect. Trionychon). The host ranges of the investigated species in Central Europe include 102 species from 12 families, most often from Asteraceae. For this purpose, ca. 400 localities were examined in the field. Moreover, data acquired from the literature and European and Asian herbaria were used.
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Abstrakt

Abstract The male-specific DNA markers are very useful in molecular sexing of non-flowering plants and seeds of dioecious species. In this paper we identified ten Y chromosome-specific RAPD primers suitable for identification of male plants in three Cannabaceae species with sex chromosomes (Humulus lupulus, XX/XY; H. japonicus, XX/XY1Y2; Cannabis sativa, XX/XY). Basing on the nucleotide sequence of the OPJ-09 RAPD product we developed the HJY09 SCAR marker, which is very efficient in sexing of Japanese hop.
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