Biologie dekompozitorů byla vždy tak trochu na druhé koleji širšího vědeckého i veřejného zájmu. Není se trochu čemu divit – než se přehrabovat v něčem nevábném, je pohodlnější pozorovat zvířata na rostlinách či jejich predátory. Nicméně dekompozitoři si naši pozornost zaslouží už jen tím, že po nás uklízejí, ať jde o kontinuální úklid koprofágů, tak o jednorázový úklid, který po nás provedou nekrofágové, a tím pomáhají udržovat to krásné a přitažlivé v chodu a stabilitě. Z koprofágů se již od věků pyramid těší jisté pozornosti koprofágní brouci, nicméně za poslední léta o nich v naší literatuře mnoho slyšet nebylo. Cílem tohoto článku je tedy představit širší veřejnosti tyto koprofágní brouky s jejich osobitou a zajímavou ekologií, která zajímavě ovlivnila jednu lidskou kulturou., Dung beetles are introduced as an important and interesting ecological group. Their ecology, what they eat and their impact on human culture and society are reviewed. Although they are no longer considered to be a deity, dung beetles still prove to be highly beneficial for both nature and human society, thanks to their degradation of dung., and František Xaver Jiří Sládeček.
Klíšťata sají obrovské množství krve, která je jejich jediným zdrojem živin a energie. Přesný enzymatický mechanismus zpracování krve ve střevě klíšťat však kupodivu nebyl donedávna vůbec znám. Náš komplexní molekulární model trávení hostitelského hemoglobinu u klíštěte obecného (Ixodes ricinus) poprvé odhalil analogii enzymatického aparátu s krevsajícími ploštěnci a hlísticemi, a zároveň tato znalost představuje zásadní poznatek pro účinný boj s klíšťaty a jimi přenášenými patogeny., Ticks (in this case Ixodidae and Argasidae) feed on enormous amounts of host blood, which provides their ultimate source of energy and nutrients. There has been only limited evidence on the exact molecular mechanisms of blood digestion in ticks. For the first time, our complex enzymatic model of proteolytic digestion in the Common Tick (Ixodes ricinus) reveals the analogy of tick intestinal proteolysis with bloodfeeding platyhelminthes and nematodes and presents a future application potential in tick or tick-borne pathogen interventions., and Daniel Sojka.
Čeleď brukvovitých patří k největším rostlinným čeledím; zahrnuje 49 tribů, 321 rodů a 3 660 druhů. Zájem vědců o tuto rostlinnou skupinu vzrostl především díky ustanovení huseníčku rolního (Arabidopsis thaliana) modelovým druhem a sekvenování jeho genomu. To v r. 2000 odstartovalo mimo jiné bouřlivý rozvoj srovnávací fylogenomiky a cytogenomiky, včetně úspěšného zavedení metody malování chromozomů (chromosome painting) huseníčku a její aplikace na další zástupce brukvovitých (srovnávací malování chromozomů; comparative chromosome painting, CCP). Metoda CCP umožňuje studium chromozomové kolinearity, rozpoznání chromozomových přestaveb, porovnání struktury chromosomů nebo jejich částí mezi jednotlivými druhy a rekonstrukci struktury celých karyotypů. Brukvovité jsou jedinou rostlinnou čeledí, u níž je v tomto rozsahu metoda CCP použitelná. Srovnávací cytogenetické mapy brukvovitých tak představují zcela unikátní typ dat o evoluci rostlinných karyotypů a genomů., Whole-genome sequencing of the model plant Arabidopsis thaliana has stimulated a rapid development of comparative phylogenomics and cytogenomics, including the invention of chromosome painting in A. thaliana and comparative chromosome painting (CCP) in other species of the Brassicaceae (Cruciferae) family. This is the only plant family in which large-scale CCP is feasible. CCP provides unique insights into the karyotype and genome evolution in plants by comparing chromosome collinearity, identification of chromosome rearrangements, construction of comparative cytogenetic maps, and reconstruction of ancestral karyotype structures., and Terezie Mandáková.
The paper reviews the past and present of the CBS. Since its establishment, it has in - fluenced the field of botany in the country by acting as a link between academics, students and amateur botanists. The founders and other prominent figures are commemorated. At present, the main CBS activities include the publication of journals (Preslia, Bulletin of the CBS, Bryonora) and the organization of Floristry Summer Schools and regular conferences and lectures. and Lubomír Hrouda.
Brassinosteroids (BRs) and polyamines, well-established growth regulators, play a key role in abiotic stress response in plants. In the present study, we examined the role of 24-epibrassinolide (EBL, an active BR) and/or putrescine (Put) in the salt-induced stress in cucumber. The 15-d-old plants were exposed to 100 mM NaCl and they were subsequently treated by exogenous EBL and/or Put. The salt stress reduced significantly plant growth and gas-exchange parameters, and increased proline content and electrolyte leakage in the leaves. Toxic effects induced by salt stress were completely overcome by the combination of EBL and Put. EBL and/or Put treatments improved the growth parameters of the NaCl-treated plants, such as shoot length, root length, fresh and dry mass. Our data also indicated that applications of EBL and Put upregulated the activities of the antioxidant enzymes, such as catalase, peroxidase, and superoxide dismutase under salt stress., Q. Fariduddin, B. A. Mir, M. Yusuf, A. Ahmad., and Obsahuje bibliografii
Seedlings of the hypoxia-sensitive cucumber cultivar were hydroponically grown under hypoxia for 7 d in the presence or absence of 24-epibrassinolide (EBR, 2.1 nM). Hypoxia significantly inhibited growth, while EBR partially counteracted this inhibition. Leaf net photosynthetic rate (PN), stomatal conductance, transpiration rate, and water-use efficiency declined greatly, while the stomatal limitation value increased significantly. The maximum net photosynthetic rate was strongly reduced by hypoxia, indicating that stomatal limitation was not the only cause of the PN decrease. EBR markedly diminished the harmful effects of hypoxia on PN as well as on stomata openness. It also greatly stimulated CO2 fixation by the way of increasing the carboxylation capacity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), ribulose-1,5-bisphosphate regeneration, Rubisco activity, and the protection of Rubisco large subunit from degradation. Our data indicated that photosystem (PS) II was damaged by hypoxia, while EBR had the protective effect. EBR further increased nonphotochemical quenching that could reduce photodamage of the PSII reaction center. The proportion of absorbed light energy allocated for photochemical reaction (P) was reduced, while both nonphotochemical reaction dissipation of light energy and imbalanced partitioning of excitation energy between PSI and PSII increased. EBR increased P and alleviated this imbalance. The results suggest that both stomatal and nonstomatal factors limited the photosynthesis of cucumber seedlings under hypoxia. EBR alleviated the growth inhibition by improving CO2 asimilation and protecting leaves against PSII damage., Y. H. Ma, S. R. Guo., and Obsahuje bibliografii
Podyjí National Park is one of the hotspots of fungal diversity in the Czech Republic (so far we know about 1400 species from this area). The main reasons for this fact (well-preserved natural habitats, habitat and geological diversity) are introduced and briefly discussed in the article. high fungal diversity is documented based on several examples of rare or endangered species, which are typical for some of the local habitats and characterize the range of ecological conditions in the studied area. and Jan Běťák.
Since 2011, a unique project studying the effect of artificial canopy opening (Small-size clearings) on biodiversity in lowland forests has been carried out in the Podyjí NP. The response of communities of butterflies, moths, epigeic, floricolous and saproxylic beetles, birds, reptiles, and vascular plants was observed for three years. The results showed a positive effect of early stages in forest succession not only for the majority of groups studied, but also for many threatened species, and also demonstrated the importance of open forest remnants for biodiversity. In protected forests at low and middle elevations, conservation management should attempt to maintain a mosaic of forest at different stages of succession. and Pavel Šebek a kolektiv autorů.
The moths belong to the best-studied groups of insects in the Podyjí NP. In total, 2250 species of butterflies and moths (Lepidoptera) have hitherto been recorded here. Many species are closely associated with rocky steppe and heeathland, the most valuable natural habitats in this terriotory. Concurrently, the Podyjí NP is located on the western distribution border of many eastern and southern species. On the other hand, a total of 13 species of butterflies and moths have now become extinct here. and Jan Šumpich, Jan Liška, Zdeněk Laštůvka.
The main objective of the management of woodland in the Podyjí National Park (NP) is to allow natural processes and support biodiversity. How the woodland has changed since designation of the NP is illustrated by changes in selected parameters (tree species composition, proportion of dead wood etc.). Some active measures to support woodland biodiversity are also presented in the paper. and Jaroslav Ponikelský a kolektiv spoluautorů.
The Podyjí NP has very diverse vegetation which results in the occurrence of rich butterfly communities. To date, 142 species of butterflies have been recordeed in this area, of which 19 species (13 %) are considered regionally extinct and three species (2 %) are only migrants, not native to the Czech fauna. The main cause of the decline in butterflies is the abandonment of traditional techniques of habitat management. To conserve and support butterfly diversity, the NP authority practices a wide range of management measures. and Milan Švestka.
Šumava lakes have been recovering over the last 30 years from acidification caused by high atmospheric deposition of sulphur and nitrogen. Regeneration was manifested by decreasing acidity and increasing biodiversity (except for fish). It was temporarily interrupted by Spruce Bark Beetle (Ips typographus) infestation in lake catchments. Spruce defoliation and changes in light and humidity conditions caused enhanced mineralization of soil humus layer resulting in nitrate leaching and also partial acidification (only temporary, within a few decades the lakes will profit from the release of nitrogen from the ecosystem). and Jakub Hruška a kol.