The movement of nuclear DNA from one vascular plant species to another in the absence of fertilization is thought to be rare. Here, nonnative rRNA gene [ribosomal DNA (rDNA)] copies were identified in a set of 16 diploid barley (Hordeum) species; their origin was traceable via their internal transcribed spacer (ITS) sequence to five distinct Panicoideae genera, a lineage that split from the Pooideae about 60 Mya. Phylogenetic, cytogenetic, and genomic analyses implied that the nonnative sequences were acquired between 1 and 5 Mya after a series of multiple events, with the result that some current Hordeum sp. individuals harbor up to five different panicoid rDNA units in addition to the native Hordeum rDNA copies. There was no evidence that any of the nonnative rDNA units were transcribed; some showed indications of having been silenced via pseudogenization. A single copy of a Panicum sp. rDNA unit present in H. bogdanii had been interrupted by a native transposable element and was surrounded by about 70 kbp of mostly noncoding sequence of panicoid origin. The data suggest that horizontal gene transfer between vascular plants is not a rare event, that it is not necessarily restricted to one or a few genes only, and that it can be selectively neutral.
- Klíčová slova
- Hordeum, Panicoideae, Triticeae, horizontal gene transfer, transposable elements,
- MeSH
- buněčné jádro genetika MeSH
- diploidie MeSH
- DNA rostlinná chemie genetika MeSH
- fylogeneze * MeSH
- ječmen (rod) klasifikace genetika MeSH
- lipnicovité klasifikace genetika MeSH
- mezerníky ribozomální DNA chemie genetika MeSH
- molekulární evoluce MeSH
- přenos genů horizontální * MeSH
- ribozomální DNA chemie genetika MeSH
- rostlinné geny genetika MeSH
- sekvenční analýza DNA MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DNA rostlinná MeSH
- mezerníky ribozomální DNA MeSH
- ribozomální DNA MeSH
A method for discriminating malting barley varieties based on direct matrix-assisted laser desorption-ionisation - time-of-flight mass spectrometry (MALDI-TOF MS) fingerprinting of proteins was developed. Signals corresponding to hordeins were obtained by simple mixing of powdered barley grain with a MALDI matrix solution containing 12.5mgmL(-1) of ferulic acid in an acetonitrile:water:formic acid 50:33:17 v/v/v mixture. Compared to previous attempts at MALDI-TOF mass spectrometric analysis of barley proteins, the extraction and fractionation steps were practically omitted, resulting in a significant reduction in analytical time and costs. The discriminatory power was examined on twenty malting barley varieties and the practicability of the method was tested on sixty barley samples acquired from Pilsner Urquell Brewery. The method is proposed as a rapid tool for variety assignment and purity determination of malting barley that may replace gel electrophoresis currently used for this purpose.
- Klíčová slova
- Barley, MALDI-TOF MS, Malting, Proteins,
- MeSH
- gluteny analýza MeSH
- ječmen (rod) chemie klasifikace metabolismus MeSH
- pivo MeSH
- průmysl zpracování potravin metody MeSH
- semenáček chemie klasifikace metabolismus MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- gluteny MeSH
The rate of population increase of three mite species, Acarus siro (L.), Lepidoglyphus destructor (Schrank) and Tyrophagus putrescentiae (Schrank), was studied on various types of barley and at various combinations of temperature and humidity. The mites were added into the chambers and incubated for 21 days on seven different kinds of barley coming from four sites, including six cultivars and a mixture. The population increase of all species was higher on the mixture than on any other cultivar, except for Sebastian and Calgary. The increase of mites was studied at constant temperatures ranging from 5 to 35 °C and relative humidity (RH) ranging from 50 to 90 %. Positive rate of increase was found above 70 % RH for all species. The optimal humidity was at 85 % RH for A. siro and L. destructor and at 90 % RH for T. putrescentiae. As concerns the temperature, positive rate of increase was found at temperatures higher than 10, 15 and 20 °C for A. siro, L. destructor and T. putrescentiae, respectively. The temperature optima were at 23, 25, and 30 °C for A. siro, L. destructor and T. putrescentiae, respectively. Model estimated on laboratory data was then fitted to temperature and humidity records from August to November in the Czech grain store. Estimated population rate of increase was rarely positive: for A. siro it was for 24 %, for L. destructor for only 1 % and for T. putrescentiae for only 7 % days of the study period. It is concluded that in the climatic conditions of the Czech Republic the population increase of three mite pests is negligible during autumn and winter.
- MeSH
- Acari fyziologie MeSH
- ječmen (rod) klasifikace MeSH
- populační dynamika MeSH
- teplota * MeSH
- vlhkost * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Fusarium toxins, secondary metabolites of toxinogenic Fusarium species, are found in a range of cereal grains. In this study the occurrence of the most commonest Fusarium toxins, namely nivalenol (NIV), deoxynivalenol (DON), deoxynivalenol-3-glucoside, fusarenon-X, 3- and 15-acetyldeoxynivalenol, HT-2 and T-2 toxins and zearalenone, in various barley cultivars harvested in 2005-2008 was monitored. The impact of weather, locality, fungicide treatment and barley cultivar (hulless or covered) on contamination was evaluated. The transfer of these mycotoxins into malt was assessed. RESULTS: The most prevalent toxin was DON, which was found in 83% of samples (maximum level 180 µg kg(-1)), while HT-2 was detected in 62% of samples (maximum level 716 µg kg(-1)). Using analysis of covariance, weather was found to be the key factor in all years (P < 0.001). A relationship between cultivar and contamination was confirmed only for HT-2 (P < 0.001) and T-2 (P = 0.037), with higher levels of these toxins being observed in hulless cultivars. With the exception of NIV (P = 0.008), no significant relationship was found between fungicide treatment and contamination. No distinct trend regarding DON levels in malt was found, with both decreases and increases occurring. CONCLUSION: The results show an inter-annual variation in mycotoxin occurrence in barley cultivars as well as differences in contamination of malt produced from fungicide-treated and untreated barley.
- MeSH
- analýza rozptylu MeSH
- druhová specificita MeSH
- fungicidy průmyslové farmakologie MeSH
- Fusarium chemie MeSH
- ječmen (rod) klasifikace mikrobiologie MeSH
- jedlá semena mikrobiologie MeSH
- mykotoxiny analýza MeSH
- počasí MeSH
- potravinářská mikrobiologie * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- fungicidy průmyslové MeSH
- mykotoxiny MeSH
