Jan Nedělník

Dr. Jan Nedělník


Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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JSJiří Skládanka
Jiří Skládanka
JNJan Nedělník
Jan Nedělník
Vojtech AdamVojtech Adam
Vojtech Adam
PDPetr Doležal
Petr Doležal
HMHana Moravcová
Hana Moravcová
VDVlastimil Dohnal
Vlastimil Dohnal
The issue of moulds and, thus, contamination with mycotoxins is very topical, particularly in connexion with forages from grass stands used at the end of the growing season. Deoxynivalenol (DON), zearalenone (ZEA), fumonisins (FUM) and aflatoxins (AFL) are among the most common mycotoxins. The aim of the paper was to determine concentrations of mycotoxins in selected grasses (Lolium perenne, Festulolium pabulare, Festulolium braunii) and their mixtures with Festuca rubra an/or Poa pratensis during the growing season as a marker of grass safety, which was assessed according to content of the aforementioned mycotoxins. During the growing season grass forage was contaminated with mycotoxins, most of all by DON and ZEA. The contents of AFL and FUM were zero or below the limit of quantification. Moreover, the level of the occurrence of mould was quantified as ergosterol content, which was higher at the specific date of cut. All results were statistically processed and significant changes were discussed.

20 September 2018 in Sustainability
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AKAntonín Kintl
Antonín Kintl
JEJakub Elbl
Jakub Elbl
TLTomáš Lošák
Tomáš Lošák
Magdalena Daria VaverkováMagdalena Daria Vaverková
Magdalena Daria Vaverková
JNJan Nedělník
Jan Nedělník
The main goal of our research was to compare the mixed intercropping (MC) of winter wheat (Triticum aestivum) and white clover (Trifolium repens) with the sole cropping of Triticum aestivum, during two growing seasons (2012–2014), in a lysimetric experiment. We aimed to investigate the effect of the above growing system on total biomass production, grain yield and leaching of mineral nitrogen (Nmin). Four variants of intercropping (0 kg N/ha; 112 kg N/ha; 112 kg N/ha + 1.25 L of humic acids/ha; 70 kg N + 0.65 L of humic acids/ha) and two variants of sole cropping (0 kg N/ha; 140 kg N/ha) were used. Research results showed a good potential for growing wheat in the mixed cropping system without any negative effect on grain and total biomass production. No significant differences were found between the variants where winter wheat was grown with white clover (70 and 112 kg N/ha), and variants with sole wheat (140 kg N/ha), in both years of the experiment. The loss of Nmin from the soil was affected by the application of N fertilizer and mixed intercropping system. During the experiment, the loss of Nmin was higher by 20% in the variant using the sole winter wheat (140 kg N/ha), than in the MC variants.

JSJiri Skladanka
Jiri Skladanka
Vojtech AdamVojtech Adam
Vojtech Adam
PDPetr Dolezal
Petr Dolezal
JNJan Nedělník
Jan Nedělník
Rene KizekRene Kizek
Rene Kizek
ANAdam Nawrath
Adam Nawrath
Mycotoxins are secondary metabolites produced by fungal species that have harmful effects on mammals. The aim of this study was to assess the content of mycotoxins in fresh-cut material of selected forage grass species both during and at the end of the growing season. We further assessed mycotoxin content in subsequently produced first-cutting silages with respect to the species used in this study: Lolium perenne (cv. Kentaur), Festulolium pabulare (cv. Felina), Festulolium braunii (cv. Perseus), and mixtures of these species with Festuca rubra (cv. Gondolin) or Poa pratensis (Slezanka). The mycotoxins deoxynivalenol, zearalenone and T-2 toxin were mainly detected in the fresh-cut grass material, while fumonisin and aflatoxin contents were below the detection limits. July and October were the most risky periods for mycotoxins to occur. During the cold temperatures in November and December, the occurrence of mycotoxins in fresh-cut material declined. Although June was a period with low incidence of mycotoxins in green silage, contents of deoxynivalenol and zearalenone in silages from the first cutting exceeded by several times those determined in their biomass collected directly from the field. Moreover, we observed that use of preservatives or inoculants did not prevent mycotoxin production.

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OTOldřich Trněný
Oldřich Trněný
DVDavid Vlk
David Vlk
EMEliška Macková
Eliška Macková
MMMichaela Matoušková
Michaela Matoušková
JRJana Repkova
Jana Repkova
DKDaniela Knotová
Daniela Knotová
Plant–rhizobia symbiosis can activate key genes involved in regulating nodulation associated with biological nitrogen fixation (BNF). Although the general molecular basis of the BNF process is frequently studied, little is known about its intraspecific variability and the characteristics of its allelic variants. This study’s main goals were to describe phenotypic and genotypic variation in the context of nitrogen fixation in red clover (Trifolium pretense L.) and identify variants in BNF candidate genes associated with BNF efficiency. Acetylene reduction assay validation was the criterion for selecting individual plants with particular BNF rates. Sequences in 86 key candidate genes were obtained by hybridization-based sequence capture target enrichment of plants with alternative phenotypes for nitrogen fixation. Two genes associated with BNF were identified: ethylene response factor required for nodule differentiation (EFD) and molybdate transporter 1 (MOT1). In addition, whole-genome population genotyping by double-digest restriction-site-associated sequencing (ddRADseq) was performed, and BNF was evaluated by the natural 15N abundance method. Polymorphisms associated with BNF and reflecting phenotype variability were identified. The genetic structure of plant accessions was not linked to BNF rate of measured plants. Knowledge of the genetic variation within BNF candidate genes and the characteristics of genetic variants will be beneficial in molecular diagnostics and breeding of red clover.

6 August 2014 in Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis
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JSJiri Skladanka
Jiri Skladanka
PDPetr Doležal
Petr Doležal
JNJan Nedělník
Jan Nedělník
HMHana Moravcová
Hana Moravcová
RPRoman Poštulka
Roman Poštulka
IVIvo Vyskočil
Ivo Vyskočil
Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis, the scientific journal of the Mendel University in Brno, Czech Republic

14 April 2022 in Agriculture
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RLRadko Loucka
Radko Loucka
JFJančík Filip
Jančík Filip
PHPetr Homolka
Petr Homolka
YTYvona Tyrolová
Yvona Tyrolová
PKPetra Kubelková
Petra Kubelková
MGMarie Gaislerová
Marie Gaislerová
Farmers need information on which maize hybrid is best and under what conditions. They demand that this information be clear, simple and easily understood. This study aims to estimate the potential for milk production (MPP) and the biochemical methane potential (BMP) production from fresh maize hybrids. Using these indicators from fresh maize, information on the differences between hybrids can be effectively obtained, albeit with some of the shortcomings of this proposed method. Samples of fresh maize plants (n = 384) from four hybrids were evaluated at two locations over four consecutive years (from 2018 to 2021). The dry matter content, averaged across all hybrids, all years and both locations, was 371 ± 42.3 g.kg−1. The colder and wetter the year, the significantly higher the starch content, lower the amylase-treated neutral detergent fibre content (aNDF) and lower the crude protein (CP), which was reflected in lower BMP. Weather did not significantly affect the net energy of lactation (NEL) or MPP values. The location significantly affected all monitored indicators, except BMP. The earlier the hybrid was at harvest time, the lower the NEL and MPP but the higher BMP contents were. This study is preliminary and must be repeated with more hybrids and under more different conditions.