Intracellular bacteria of the genus Wolbachia (α-Proteobacteria) are the most widespread endosymbionts of insects. Host infection is usually associated with alterations in reproduction, such as cytoplasmic incompatibility, the induction of parthenogenesis and offspring sex ratio bias: all phenomena that may influence host speciation. In the present study, by using well-established molecular tools, we investigated the presence of Wolbachia in leaf beetles of the genus Crioceris and their host plants, which are various species of Asparagus. Multilocus sequence typing of bacterial genes showed that despite their occurrence in the same habitat and feeding on the same plant, two species of Crioceris, C. quinquepunctata and C. quatuordecimpunctata, are infected by two different strains of Wolbachia. C. asparagi, C. paracenthesis and C. duodecimpunctata, which are sympatric with the infected species, do not harbour the bacterium. Interestingly, DNA of Wolbachia was detected in host plant tissues that are exploited by the beetles, providing evidence for the horizontal transmission of the bacterium between beetles and their host plants. Moreover, Wolbachia was detected in species of Crioceris that are not closely related., Michał Kolasa, Matteo Montagna, Valeria Mereghetti, Daniel Kubisz, Miłosz A. Mazur, Łukasz Kajtoch., and Obsahuje bibliografii
Anthoxanthum odoratum (Sweet Vernal Grass), is a widespread grass species native to Eurasia and common also in the Czech Republic. Its name is derived from distinct scent, particularly strong in dry state, caused by coumarins. Eight other Anthoxanthum species can be found in Europe, one of which (A. alpinum) occurs in the Czech Republic. It replaces A. odoratum at higher altitudes. The genus encompasses both di - ploids and polyploids that have complex evolutionary history. We used DNA flow cytometry together with molecular markers to gain detailed insights into evolutionary processes shaping the genus. and Zuzana Khodlová, Pavel Trávníček.
Autoři pojednávají o vitamínu D, který má mezi ostatními vitamíny specifické postavení, poněkud z jiného úhlu pohledu. Přibližují jeho evoluční původ a historii jeho objevování. Nedostatek vitaminu D vyvolává křivici, nemoc, která je doložena už od starověku. V této souvislosti upozorňují autoři na světově uznávané zásluhy významného, dnes už téměř zapomenutého českého vědce E. H. Kodíčka. Přehledně také popisují metabolismus a transport vitaminu D v organismu a upozorňují, že vitamin D také hraje důležitou úlohu při vzniku chronických nesdělných chorob, jejichž počet celosvětově stále vzrůstá., The authors discuss vitamin D, which has a special position among vitamins, from a somewhat different perspective. They clarify its evolutionary origin and the history of its discovery. A deficiency of vitamin D causes rickets, a disease that has been documented since antiquity. In this context, the authors draw attention to a nearly forgotten Czech scientist E. H. Kodíček of significant merit. They also briefly describe the metabolism and transport of vitamin D in the body and point out that vitamin D also plays an important role in the development of non-communicable chronic diseases, the number of which is increasing worldwide., and Petr Šíma, Bohumil Turek.
Categorizing inter-specific relationships might be very difficult as the participating species may play various roles. Using the example of Caribbean Shrimps (Typton carneus) we show that it is possible to consider one interaction to be described as mutualism, commensalism or parasitism, depending on our point of view. and Petr Jan Juračka ... [et al.].
Cartilaginous fish of the suborder stingray (Myliobatoidei) have evolved an efficient active self-defence method against potential predators via a poisonous tail spine with a unique venom delivery system and a poorly described venom composition. Abrief overview of this defence mechanism is followed by a description of injury from an encounter with the Whiptail Stingray (Dasyatis margarita) on the mangrove shore of Guinea–Bissau (West Africa). and Aleš Buček, Petr Jan Juračka.
Reproduction of common frog species (Bufo bufo and Rana temporaria) in commercially managed fishponds can be threa - tened due to destruction of egg clutches or early developmental stages of tadpoles. The phenomenon is described based on a monitoring of a forest fishpond in the south-eastern part of Central Bohemia. Data on the size and growth of egg clutches and tadpoles in relation to time and weather conditions are also described and Ivan Vergner.
Three gall midge species displaying remarkable distribution in the Palaearctic region (Lasioptera artemisiae, Dasineura corniculata, Lasioptera eryngii) the causes of which cannot be explained, are discussed. and Václav Skuhravý, Marcela Skuhravá.