BACKGROUND: The southern African Oxalis radiation is extremely morphologically variable. Despite recent progress in the phylogenetics of the genus, there are few morphological synapomorphies supporting DNA-based clades. Leaflet anatomy can provide an understudied and potentially valuable source of information on the evolutionary history and systematics of this lineage. Fifty-nine leaflet anatomical traits of 109 southern African Oxalis species were assessed in search of phylogenetically significant characters that delineate clades. RESULTS: A combination of 6 leaflet anatomical traits (stomatal position, adaxial epidermal cells, abaxial epidermal cells, mesophyll, sheath around vascular tissue, degree of leaflet conduplication) clearly support various clades defined by previous DNA-based phylogenetic work. Other, mostly continuous leaflet anatomical traits were highly variable and showed less phylogenetic pattern. CONCLUSIONS: Major and unexpected findings include the transition from ancestral hypostomatic leaflets to adaxially-located stomata in the vast majority of southern African Oxalis, the loss of semi-swollen AB epidermal cells and the gain of swollen adaxial and abaxial epidermal cells in selected clades, and multiple changes from ancestral bifacial mesophyll to isobilateral or homogenous mesophyll types. The information gathered in this study will aid in the taxonomic revision of this speciose member of the Greater Cape Floristic Region and provide a basis for future hypotheses regarding its radiation.

• MeSH
• biologická evoluce MeSH
• cévní svazky rostlin cytologie   MeSH
• duplikace genu MeSH
• fenotyp MeSH
• fylogeneze * MeSH
• kvantitativní znak dědičný MeSH
• listy rostlin anatomie a histologie   cytologie   genetika   MeSH
• mezofylové buňky cytologie   MeSH
• Oxalidaceae anatomie a histologie   genetika   MeSH
• průduchy rostlin cytologie   MeSH
• trichomy cytologie   MeSH
• Publikační typ
• časopisecké články MeSH

Phylogenetics benefits from using a large number of putatively independent nuclear loci and their combination with other sources of information, such as the plastid and mitochondrial genomes. To facilitate the selection of orthologous low-copy nuclear (LCN) loci for phylogenetics in nonmodel organisms, we created an automated and interactive script to select hundreds of LCN loci by a comparison between transcriptome and genome skim data. We used our script to obtain LCN genes for southern African Oxalis (Oxalidaceae), a speciose plant lineage in the Greater Cape Floristic Region. This resulted in 1164 LCN genes greater than 600 bp. Using target enrichment combined with genome skimming (Hyb-Seq), we obtained on average 1141 LCN loci, nearly the whole plastid genome and the nrDNA cistron from 23 southern African Oxalis species. Despite a wide range of gene trees, the phylogeny based on the LCN genes was very robust, as retrieved through various gene and species tree reconstruction methods as well as concatenation. Cytonuclear discordance was strong. This indicates that organellar phylogenies alone are unlikely to represent the species tree and stresses the utility of Hyb-Seq in phylogenetics.

• MeSH
• fylogeneze MeSH
• genetická variace * MeSH
• genetické markery * MeSH
• genom MeSH
• genotypizační techniky metody   MeSH
• Oxalidaceae klasifikace   genetika   MeSH
• sekvenční analýza DNA MeSH
• transkriptom MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• Geografické názvy
• jižní Afrika MeSH

BACKGROUND AND AIMS: Genome duplication is widely acknowledged as a major force in the evolution of angiosperms, although the incidence of polyploidy in different floras may differ dramatically. The Greater Cape Floristic Region of southern Africa is one of the world's biodiversity hotspots and is considered depauperate in polyploids. To test this assumption, ploidy variation was assessed in a widespread member of the largest geophytic genus in the Cape flora: Oxalis obtusa. METHODS: DNA flow cytometry complemented by confirmatory chromosome counts was used to determine ploidy levels in 355 populations of O. obtusa (1014 individuals) across its entire distribution range. Ecological differentiation among cytotypes was tested by comparing sets of vegetation and climatic variables extracted for each locality. KEY RESULTS: Three majority (2x, 4x, 6x) and three minority (3x, 5x, 8x) cytotypes were detected in situ, in addition to a heptaploid individual originating from a botanical garden. While single-cytotype populations predominate, 12 mixed-ploidy populations were also found. The overall pattern of ploidy level distribution is quite complex, but some ecological segregation was observed. Hexaploids are the most common cytotype and prevail in the Fynbos biome. In contrast, tetraploids dominate in the Succulent Karoo biome. Precipitation parameters were identified as the most important climatic variables associated with cytotype distribution. CONCLUSIONS: Although it would be premature to make generalizations regarding the role of genome duplication in the genesis of hyperdiversity of the Cape flora, the substantial and unexpected ploidy diversity in Oxalis obtusa is unparalleled in comparison with any other cytologically known native Cape plant species. The results suggest that ploidy variation in the Greater Cape Floristic Region may be much greater than currently assumed, which, given the documented role of polyploidy in speciation, has direct implications for radiation hypotheses in this biodiversity hotspot.

• MeSH
• biodiverzita MeSH
• chromozomy rostlin MeSH
• genetická variace * MeSH
• Magnoliopsida cytologie   genetika   MeSH
• ploidie * MeSH
• populační genetika MeSH
• průtoková cytometrie metody   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• jižní Afrika MeSH

The use of non-standard low-temperature conditions in environmental scanning electron microscopy might be promising for the observation of coniferous tissues in their native state. This study is aimed to analyse and evaluate the method based on the principle of low-temperature sample stabilization. We demonstrate that the upper mucous layer is sublimed and a microstructure of the sample surface can be observed with higher resolution at lower gas pressure conditions, thanks to a low-temperature method. An influence of the low-temperature method on sample stability was also studied. The results indicate that high-moisture conditions are not suitable for this method and often cause the collapse of samples. The potential improvement of stability to beam damage has been demonstrated by long-time observation at different operation parameters. We finally show high applicability of the low-temperature method on different types of conifers and Oxalis acetosella.

• MeSH
• cévnaté rostliny metabolismus   ultrastruktura   MeSH
• extracelulární matrix metabolismus   ultrastruktura   MeSH
• mikroskopie elektronová rastrovací metody   MeSH
• nízká teplota * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Four plants, Cirsium arvense (creeping thistle), Equisetum arvense (field horsetail), Oxalis acetosella (wood sorrel) and Phragmites australis (common reed), which grew in an abandoned Sb-mining area in Pernek (Malé Karpaty Mts., Slovakia), were investigated for the yeast species. Yeasts were isolated from both the leaves of the plants and the soil adjacent to the plants. In total, 65 yeast cultures, belonging to 11 ascomycetous and 5 basidiomycetous yeast species, were isolated. The species most frequently isolated from both the soil and leaf samples were Trichosporon porosum, Galactomyces candidus and Candida solani, whereas Aureobasidium pullulans, Candida tsuchiyae and Sporidiobolus metaroseus were isolated exclusively from the plant leaves. All the yeast species isolated were tested for their tolerance to two heavy metals (Cd, Zn) and three metalloids (As, Sb and Si). The yeasts isolated from both the leaves and soils exhibited a high tolerance level to both As and Sb, present in elevated concentrations at the locality. Among the yeast species tested, Cryptococcus musci, a close relative to Cryptococcus humicola, was the species most tolerant to all the chemical elements tested, with the exception of Si. It grew in the presence of 200 mmol/L Zn, 200 mmol/L Cd, 60 mmol/L As and 50 mmol/L Sb, and therefore, it can be considered as a multi-tolerant species. Some of the yeast species were tolerant to the individual chemical elements. The yeast-like species Trichosporon laibachii exhibited the highest tolerance to Si of all yeasts tested, and Cryptococcus flavescens and Lindnera saturnus showed the same tolerance as Cryptococcus musci to Zn and As, respectively. The majority of the yeasts showed a notably low tolerance to Cd (not exceeded 0.5 mmol/L), which was present in small amounts in the soil. However, Candida solani, isolated from the soil, exhibited a higher tolerance to Cd (20 mmol/L) than to As (2 mmol/L).

• MeSH
• biologická adaptace * MeSH
• hornictví * MeSH
• kvasinky * růst a vývoj   izolace a purifikace   MeSH
• listy rostlin mikrobiologie   MeSH
• mikrobiologie životního prostředí * MeSH
• nebezpečné látky * MeSH
• půda chemie   MeSH
• rostliny mikrobiologie   MeSH
• životní prostředí * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Slovenská republika MeSH

Novel species of fungi described in this study include those from various countries as follows: Australia, Chaetopsina eucalypti on Eucalyptus leaf litter, Colletotrichum cobbittiense from Cordyline stricta × C. australis hybrid, Cyanodermella banksiae on Banksia ericifolia subsp. macrantha, Discosia macrozamiae on Macrozamia miquelii, Elsinoë banksiigena on Banksia marginata, Elsinoë elaeocarpi on Elaeocarpus sp., Elsinoë leucopogonis on Leucopogon sp., Helminthosporium livistonae on Livistona australis, Idriellomyces eucalypti (incl. Idriellomyces gen. nov.) on Eucalyptus obliqua, Lareunionomyces eucalypti on Eucalyptus sp., Myrotheciomyces corymbiae (incl. Myrotheciomyces gen. nov., Myrotheciomycetaceae fam. nov.), Neolauriomyces eucalypti (incl. Neolauriomyces gen. nov., Neolauriomycetaceae fam. nov.) on Eucalyptus sp., Nullicamyces eucalypti (incl. Nullicamyces gen. nov.) on Eucalyptus leaf litter, Oidiodendron eucalypti on Eucalyptus maidenii, Paracladophialophora cyperacearum (incl. Paracladophialophoraceae fam. nov.) and Periconia cyperacearum on leaves of Cyperaceae, Porodiplodia livistonae (incl. Porodiplodia gen. nov., Porodiplodiaceae fam. nov.) on Livistona australis, Sporidesmium melaleucae (incl. Sporidesmiales ord. nov.) on Melaleuca sp., Teratosphaeria sieberi on Eucalyptus sieberi, Thecaphora australiensis in capsules of a variant of Oxalis exilis.Brazil, Aspergillus serratalhadensis from soil, Diaporthe pseudoinconspicua from Poincianella pyramidalis, Fomitiporella pertenuis on dead wood, Geastrum magnosporum on soil, Marquesius aquaticus (incl. Marquesius gen. nov.) from submerged decaying twig and leaves of unidentified plant, Mastigosporella pigmentata from leaves of Qualea parviflorae, Mucor souzae from soil, Mycocalia aquaphila on decaying wood from tidal detritus, Preussia citrullina as endophyte from leaves of Citrullus lanatus, Queiroziella brasiliensis (incl. Queiroziella gen. nov.) as epiphytic yeast on leaves of Portea leptantha, Quixadomyces cearensis (incl. Quixadomyces gen. nov.) on decaying bark, Xylophallus clavatus on rotten wood. Canada, Didymella cari on Carum carvi and Coriandrum sativum.Chile, Araucasphaeria foliorum (incl. Araucasphaeria gen. nov.) on Araucaria araucana, Aspergillus tumidus from soil, Lomentospora valparaisensis from soil. Colombia, Corynespora pseudocassiicola on Byrsonima sp., Eucalyptostroma eucalyptorum on Eucalyptus pellita, Neometulocladosporiella eucalypti (incl. Neometulocladosporiella gen. nov.) on Eucalyptus grandis × urophylla, Tracylla eucalypti (incl. Tracyllaceae fam. nov., Tracyllalales ord. nov.) on Eucalyptus urophylla.Cyprus, Gyromitra anthracobia (incl. Gyromitra subg. Pseudoverpa) on burned soil. Czech Republic, Lecanicillium restrictum from the surface of the wooden barrel, Lecanicillium testudineum from scales of Trachemys scripta elegans. Ecuador, Entoloma yanacolor and Saproamanita quitensis on soil. France, Lentithecium carbonneanum from submerged decorticated Populus branch. Hungary, Pleuromyces hungaricus (incl. Pleuromyces gen. nov.) from a large Fagus sylvatica log. Iran, Zymoseptoria crescenta on Aegilops triuncialis.Malaysia, Ochroconis musicola on Musa sp. Mexico, Cladosporium michoacanense from soil. New Zealand, Acrodontium metrosideri on Metrosideros excelsa, Polynema podocarpi on Podocarpus totara, Pseudoarthrographis phlogis (incl. Pseudoarthrographis gen. nov.) on Phlox subulata.Nigeria, Coprinopsis afrocinerea on soil. Pakistan, Russula mansehraensis on soil under Pinus roxburghii.Russia, Baorangia alexandri on soil in deciduous forests with Quercus mongolica.South Africa, Didymocyrtis brachylaenae on Brachylaena discolor.Spain, Alfaria dactylis from fruit of Phoenix dactylifera, Dothiora infuscans from a blackened wall, Exophiala nidicola from the nest of an unidentified bird, Matsushimaea monilioides from soil, Terfezia morenoi on soil. United Arab Emirates, Tirmania honrubiae on soil. USA, Arxotrichum wyomingense (incl. Arxotrichum gen. nov.) from soil, Hongkongmyces snookiorum from submerged detritus from a fresh water fen, Leratiomyces tesquorum from soil, Talaromyces tabacinus on leaves of Nicotiana tabacum.Vietnam, Afroboletus vietnamensis on soil in an evergreen tropical forest, Colletotrichum condaoense from Ipomoea pes-caprae. Morphological and culture characteristics along with DNA barcodes are provided.

• MeSH
• fylogeneze MeSH
• houby * klasifikace   MeSH
• taxonomické DNA čárové kódování MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Sorption properties of selected sorbents suitable to remove Platinum group cytostatics from hospital waste water and from model solutions of selected Pt group cytostatics were evaluated. Suitable sorbents – Clinoptilolite, Bentonite (from Braňany, Czech Republic), Lufa and Supersorbon were selected for testing the Platinum cytostatics removal by the process of sorption from contaminated waste water. Supersorbon activated coal and Bentonite (Braňany) were evaluated as efficient sorbents suitable for all tested Pt cytostatics, which probably relates to their structure – the largest volume of pores, porosity and specific surface area. During testing it was found that Platinum compounds precipitate out of the solutions, while this was insignificant only in the Carboplatin solution. This reached up to 85 % in several tests with Cisplatin and Oxali-platin solutions. It was shown that this phenomena occur even in case of the real hospital waste water.

• Klíčová slova
• cytostatika platinové řady, metody čištění kontaminovaných vod, sorpční experimenty, sorpce, sorbenty,
• MeSH
• cytostatické látky toxicita   MeSH
• nemocnice MeSH
• odpadní voda * analýza   toxicita   MeSH
• platina toxicita   MeSH
• sloučeniny platiny toxicita   MeSH
• Publikační typ
• práce podpořená grantem MeSH