No abstract

Endopolyploidy is a condition of a cell containing reduplicated genetic material in its nucleus. Cells with the nuclei of different ploidy levels are often present within a single polysomatic organism. Endoreduplication is thus a modified cell cycle that omits cytokinesis and leads to chromatin replication in the endopolyploid cells. This study aimed to research the effect of salinity on endopolyploidy of Trifolium pratense and T. repens. Both species are important pasture legumes and belong to the genus Fabaceae with the well documented endopolyploidy occurence. Endopolyploidy levels in the seedlings treated with 0, 30, 60, 90 and 120 mM NaCl were investigated by flow cytometry. The seedling organs were evaluated during three ontogeny stages. The cytometric data plotted on a histogram showed the presence of 2C-16C nuclei in T. pratense and 2C-8C in T. repens. The hypothesis that salinity induces additional endocycles was not confirmed. Our results show that the distribution of nuclei among ploidy levels does not differ markedly between the treatment groups and the control ones. Additionally, only minor changes were observed among the endoreduplication indexes (EI) of plant organs after exposure to various salt concentrations. Endopolyploidy patterns within the salt-treated seedlings during ontogeny are similar to the controls. We suggest that endopolyploidy in Trifolium species is a conserved genetic trait, rather than an adaptation to salinity stress. The analyses of the roots of T. pratense at stage III show that with the increased concentrations of NaCl the length of roots decreased, but no evident changes in endopolyploidy occured.

Borrelia miyamotoi, recurrent fever borrelia, pathogenic to humans, has been found recently in Ixodes ricinus ticks. There is still little information about its circulation in nature and potential local impact on human health as well as the occurrence in natural localities. In our study, a total of 1609 ticks (745 nymphs, 358 females and 506 males) collected from different localities in eastern Slovakia were analysed using a polymerase chain reaction targeting a gene encoding glycerophosphodiester phosphodiesterase (glpQ), which is specific to the Borrelia species in the relapsing fever group.B. miyamotoi was found in 3 nymphs, 6 females and 9 males of quested I. ricinus ticks.Although no human case of infection with B. miyamotoi has been reported in Slovakia yet, its presence needs to be studied to obtain knowledge regarding the prevalence and the distribution of this human pathogen in questing ticks and to increase medical healthcare awareness.