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Open access

Katarína Ondreičková and Ján Kraic

Abstract

Field trials with the genetic modified (GM) maize stacked hybrid NK603 × MON810 performed in two different locations in the Czech Republic were used for evaluation of genetic diversity of rhizosphere bacterial communities using the terminal restriction fragment length polymorphism. Statistically significant differences in the number of terminal restriction fragments (i.e. bacterial richness) between GM and non-GM maize were not detected. Diversity indices (Gini-Simpson and Shannon’s) revealed higher bacterial diversity in non-GM sample from location Ivanovice na Hané and in the GM maize from location Probluz, but statistical significant differences between GM and non-GM samples were not detected. Additionally, using principal component analysis and cluster analysis, no substantial variation in the composition of bacterial communities between GM and conventional maize were observed but the differences among individual collection sites were recorded.

Open access

Veronika Masárová, Daniel Mihálik and Ján Kraic

Abstract

Repetitive tandem sequences were retrieved within nucleotide sequences of opium poppy (Papaver somniferum L.) genomic DNA available in the GenBank® database. Altogether 538 different microsatellites with the desired length characteristics of tandem repeats have been identified within 450 sequences of opium poppy DNA available in the database. The most frequented were mononucleotide repeats (246); nevertheless, 44 dinucleotide, 148 trinucleotide, 62 tetranucleotide, 28 pentanucleotide and 5 hexanucleotide tandem repeats have also been found. The most abundant were trinucleotide motifs (27.50%), and the most abundant motifs within each group of tandem repeats were TA/AT, TTC/GAA, GGTT/AACC and TTTTA/ TAAAA. Five hexanucleotide repeats contained four different motifs.

Open access

Martin Sák, Ivana Dokupilová, Daniel Mihálik, Jana Lakatošová, Marcela Gubišová and Ján Kraic

Abstract

The in vitro cell cultures of Vitis vinifera L. cv. St. Laurent were treated with two elicitors - synthetic methyl jasmonate and natural, prepared from grapevine plant infected with the Phaeomoniella chlamydospora, the agent causing the Esca disease of grapevine. Efficiency of phenolic compounds production after elicitation of cell culture was analysed immediately after treatment (15 min, 30 min, 60 min) and later (after 24, 48, and 72 hours). The cell growth and content of phenolic compounds (+)-catechin, (-)-epicatechin, p-coumaric acid, syringaldehyde, rutin, vanillic acid, and trans-resveratrol were analysed in cultivated cells as well as in cultivation medium. Pch-treatment increased production of total polyphenols the most significantly 15 min after the elicitation and in optimal time was 2.86 times higher than in nonelicited culture and 1.44 times higher than in MeJa induced cell culture.

Open access

Michaela Havrlentová, Zuzana Petruláková, Alena Burgárová, Soňa Gavurníková, Viera Červená, Ernest Šturdík, Ján Kraic and Alžbeta Žofajová

Microbiological and sensory evaluations of bread and ketchup supplemented with β-D-glucan hydrogels isolated from wheat, oat, barley, and rye were carried out. Adding hydrocolloids did not affect sensory parameters of bread negatively; moreover rye and oat β-D-glucans improved the total tastiness of bread. Water activity values in fortified breads showed β-D-glucans, except isolated from oat, as elements moderately increasing this parameter and subsequently increasing also bread freshness during the storage. All β-D-glucans resulted in softening the acidic taste of ketchup and did not negatively influence the total tastiness. Quality of fortified fresh tomato ketchups and stored for 180 days, were also not negatively influenced by the addition of hydrocolloids. Therefore, cereal hydrocolloids could be very perspective in the further exploitation in preparing new health-beneficial foods.

Open access

Martina Hudcovicová, Katarína Ondreičková, Pavol Hauptvogel and Ján Kraic

Abstract

A set of 33 wheat EST-SSR markers was designed and 18 from them were polymorphic and used for assessment of genetic diversity within 36 introduced genotypes of hexaploid bread wheat. Altogether 105 alleles were detected, in average 3.18 alleles per locus. Maximum number of alleles 14 was detected at the locus TDI389708. Five the most polymorphic markers were used for the evaluation and comparison of genetic variation within 46 domestic (Slovak) wheat genotypes and 36 introduced (foreign) wheat genotypes. The number of alleles per used primer pair within domestic genotypes varied from 7 to 19, with an average of 13.2 alleles, an average gene diversity 0.846 and PIC 0.980 per locus. The number of alleles per primer within introduced genotypes varied from 7 to 14, with an average of 10.8 alleles, an average gene diversity 0.780 and PIC 0.958 per locus. The level of polymorphism in EST- SSRs was sufficient for discrimination between genotypes and variation within domestic genotypes was slightly higher than in introduced genotypes. Variation revealed by 5 selected EST-SSR markers clustered genotypes according to origin. Domestic and introduced wheats were grouped distinctly into two separate groups.

Open access

Michaela Havrlentová, Ľubomíra Deáková, Ján Kraic and Alžbeta Žofajová

Abstract

Plants have evolved to live in environments where they are often exposed to different stress factors. Being sessile, they have developed specific mechanisms that allow them to detect precisely environmental changes and respond to complex conditions, minimizing damage while conserving valuable resources for growth and reproduction. The cell wall polysaccharide β-D-glucan observed in some species of Poales can determine responses to various environmental factors in specific plant developmental stages. It is located in the outer epidermal layer, at the place of stress attack and therefore its metabolism could relate to response of plant to environmental factors within moderate, physiological range. Putative protective role of β-D-glucan during heat stress was indicated through naked oats with higher content of β-D-glucan. It appeared that oats with higher β-D-glucan content are better adapted to stress conditions. The presented article discusses the β-D-glucan as a possible protective mechanism in oat during (heat) stress conditions.

Open access

Martina Hudcovicová, Erika Korbelová, Svetlana Šliková, Lenka Klčová, Daniel Mihálik and Ján Kraic

Abstract

Molecular selection among newly created tomato and pepper lines was applied for identification of lines possessing DNA markers linked with the resistant loci against tobamoviruses ToMV, TMV, PaMMV, and PMMoV. Only four tomato lines among 184 had DNA marker linked with the resistant allele Tm-2 conferring homozygosity at this locus. Resistance of these four lines was tested and confirmed also by virological testing by inoculation with TMV strain 0. Simultaneously tested lines heterozygous at this locus expressed full or unbalanced resistance. Fifty-eight out of 62 tested pepper lines had only marker linked to susceptible allele of the locus L. Three lines derived from tobamovirus resistant pepper cultivars Brill and Brilliant expressed marker linked to resistant allele L3, and only one line derived from resistant cultivar Hurricane possessed both markers. Four selected pepper lines declared resistance also after artificial inoculation with the TMV P0 pathotype. Molecular selection, both in tomato and pepper breeding lines, may be useful in breeding programs directed to tobamovirus resistance.

Open access

Maria Maliarova, Tibor Maliar, Jana Girmanova, Jozef Lehotay and Jan Kraic

Abstract

The Humulus lupulus L. is well known as necessary raw material for beer production. The main structural classes of chemical compounds identified from hop cones include terpenes, bitter acids, prenylated chalcones, and flavonol glycosides. They were subjects of presented work. The content of quercetin was found in the range 490 - 1092 μg/g and that of kaempferol from 218 to 568 μg/g of the dry hop cones. The content of isorhamnetin was very low in all varieties. From biological activities in vitro point of view, relative high level of inhibition activity was observed for six hop genotypes - Zlatan, Lučan, and the Oswald's clones 31, 70, 71, 72, 114 on both enzymes thrombin and urokinase, but without correlation to analyzed flavonols content. In spite of this, antioxidant activity, measured by both the BCLM and HPE methods, was found high and seem to be in correlation with content of analyzed flavonols. Particularly the Oswald's clone 114 expressed very potent biological activities. In general, obtained results indicate that hop cones are valuable material also for other application others than beer production.

Open access

Michaela Havrlentová, Ivana Pšenáková, Alžbeta Žofajová, Ľubomír Rückschloss and Ján Kraic

Abstract

Improving the micronutrients in food has become an important field of the Second Green Revolution. In recent years, minor bioactive compounds such as polyphenols, pigments and carotenoids, have attracted more and more interest from both researchers and food manufactures as health-promoting and disease-preventing effects in both in vitro and in vivo studies. One of plant pigments, wheat anthocyanins as plant phenolics are increasingly attractive as natural compounds positively affecting consumer´s health and condition moreover wheat is staple food source consumed usually daily. For a purple, blue, or red colour of wheat seed are responsible glycosylated cyanidins, delphinidins, malvinidins, pelargonidins, petunidins, and peonidins located in aleurone layer or pericarp, respectively. Other than white seed colour is not natural for common hexaploid wheat but this trait can be introduced from donors by aimed breeding programs. The way of wheat anthocyanins to provide positive effects for consumer´s physiology is limited due to their specific occurrence in seed parts usually removed during grain milling practice and lower stability during processing to foods

Open access

Michaela Piliarová, Katarína Ondreičková, Martina Hudcovicová, Daniel Mihálik and Ján Kraic

Abstract

Arbuscular mycorrhizal fungi living in the soil closely collaborate with plants in their root zone and play very important role in their evolution. Their symbiosis stimulates plant growth and resistance to different environmental stresses. Plant root system, extended by mycelium of arbuscular mycorrhizal fungi, has better capability to reach the water and dissolved nutrients from a much larger volume of soil. This could solve the problem of imminent depletion of phosphate stock, affect plant fertilisation, and contribute to sustainable production of foods, feeds, biofuel, and raw materials. Expanded plant root systems reduce erosion of soil, improve soil quality, and extend the diversity of soil microflora. On the other hand, symbiosis with plants affects species diversity of arbuscular mycorrhizal fungi and increased plant diversity supports diversity of fungi. This review summarizes the importance of arbuscular mycorrhizal fungi in relation to beneficial potential of their symbiosis with plants, and their function in the ecosystem.