Marcin Domaciuk

The process was examined or the effect of culture conditions on in vitro gynogenesis in red beet was analyzed, conditions were modified or optimized. A significant influence of the genotype on the gynogenesis process was demonstrated. Of the eight genotypes, 58.3% planted ovules regenerated embryo-like structures in breeding line 411, 2.1% in RA-10, RA-11, RA-12 breeding lines and 0.9% embryo-like structures in Opolski. For the gynogenesis induction, B5 medium containing 0.1 mg L–1 2,4-dichlorophenoxyacetic acid was the most effective from all tested media. On this medium, the highest number of gynogenetic embryo-like structures was obtained. Most of the plants were regenerated on MS medium supplemented with 30 g L–1 sucrose, 0.2 mg L–1 6-benzylaminopurine and 1 mg L–1 indole-3-acetic acid. Thirty nine percent of regenerated plants acclimatized. Cytometric evaluation of gynogenetic plants of four tested genotypes revealed that in three genotypes, 100% of tested plants were haploid. Plants showed diploid ploidy level in one genotype. Isoenzymatic analysis of gynogenetic plants demonstrated that 95% and 70% of examined populations were homozygotic for the phosphohexose isomerase isoenzyme and the aspartato aminotransferase isoenzyme, respectively. During the next generation sequencing, 93% of reads were successfully mapped, from which 83% to 85% were mapped in pairs. For 15% of pairs it was clear that obtained sequence was fully homozygous, the rest of the readings were not unambiguous, but similar to the sequence of a homozygous base pair system.

The virulence patterns observed in viruses transmitted by Varroa destructor implied a potential association of these honey bee pests in Poland with the Korean haplotype. Nevertheless, it is noteworthy that this hypothesis lacked direct verification. Therefore, the aim of the study was to determine the haplotype affiliation of V. destructor mites infesting bees in Poland and Ukraine. Adult females were collected from drone brood from honey bee colonies maintained in the apiary at the University of Life Sciences in Lublin, Poland, and the apiary in Synevyr National Park in Ukraine. The haplotype affiliation was determined through the sequencing of the cytochrome oxidase subunit I gene (CO I; 929 bp) fragment. Based on the phylogenetic comparison with 84% bootstrap support, the V. destructor females from both locations were confirmed to represent three haplotypes: Korean 1 (AmK1-1), Korean 2 (AmK1-2), and Chinese 4 (AmK1-4). They are the most virulent types of this parasite worldwide and in Poland. Concurrently, the present study confirms that the Synevyr National Park in Ukraine is isolated from alien bee subspecies, but is not free from alien parasites.

Yacon becomes an important plant with strong medical and dietary potential. Therefore, studies on the optimization of yacon micropropagation were undertaken. Reproduction of yacon is conducted by traditional methods with green seedlings or long offsets taken from the underground and aboveground rootstock. The influence of different disinfection methods, various initial explants and growth regulators, their concentrations, and combinations on the efficiency of micropropagation have been analyzed. The most effective disinfection was the use of 70% ethanol and 0.5% Tween 20. The optimal initial explants were apical and lateral buds cultured on Murashige and Skoog (MS) medium with 0.2 mg L–1 kinetin and 1 mg L–1 indole-3-acetic acid. The most intensive shoot regeneration occurred on MS medium with 1 mg L–1 thidiazuron and 1-naphthylacetic acid. Histological observations demonstrated the strong effect of growth substances on shoot organogenesis from callus tissue. Shoots obtained from in vitro cultures rooted easily on modified MS media with ½ or ¼ concentration of macroelements, 20 g L–1 sucrose and 3 mg L–1 1-naphthylacetic acid. All plants adapted to ex vitro conditions.

The anatomical structure and the distribution of arabinogalactan proteins were investigated in the ovule of an energetic plant Sida hermaphrodita (L.) Rusby after pollination. Material was collected from an experimental field of the University of Life Sciences in Lublin (Felin). After embedding for immunoflurescence, semi-thin sections were stained with toluidine blue or incubated with JIM 13 or MAC 207 monoclonal antibodies for immunolabeling of arabinogalactan proteins. The structure of the ovule showed some differences in comparison to other representatives of the Malvaceae family. Conversely, the distribution of arabinogalactan proteins did not differ significantly from their distribution in the ovules of other angiosperms at the investigated stage of development.