Potato represents the third most important crop worldwide and therefore to understand regulations of tuber onset is crucial from both theoretical and practical points of view. Photosynthesis and related carbohydrate status along with phytohormone balance belong to the essential factors in regulation of plant development including storage organ formation. In our work we used potato (Solanum tuberosum) cv. Lada and its spontaneously tuberizing mutant (ST plants) grown in vitro under low carbohydrate availability (non-inductive conditions). Small plant phenotype and readiness to tuberization of ST plants was, however, not accompanied by lower gibberellins levels, as determined by UHPLC-MS/MS. Therefore, we focused on the other inducing factor, carbohydrate status. Using HPLC, we followed changes in carbohydrate distribution under mixotrophic (2.5% sucrose in medium) and photoautotrophic conditions (no sucrose addition and higher gas and light availability) and observed changes in soluble carbohydrate allocation and starch deposition, favouring basal stem part in mutants. In addition, the determination of tuber-inducing marker gene expressions revealed increased levels of StSP6A in ST leaves. Collectively these data point towards the possibility of two parallel cross-talking pathways (carbohydrate - and gibberellin- dependent ones) with the power of both to outcompete the other one when its signal is for some reason extraordinary strong.
- Keywords
- Carbohydrate distribution, Gibberellin, Photoautotrophic cultivation, Potato, Tuberization,
- MeSH
- Plants, Genetically Modified genetics metabolism MeSH
- Gibberellins metabolism MeSH
- Plant Tubers genetics metabolism MeSH
- Carbohydrate Metabolism genetics physiology MeSH
- Gene Expression Regulation, Plant genetics physiology MeSH
- Plant Proteins genetics metabolism MeSH
- Solanum tuberosum genetics metabolism MeSH
- Tandem Mass Spectrometry MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Gibberellins MeSH
- Plant Proteins MeSH
DNA microarray assay has become a useful tool for gene expression studies. Less frequent is its application to detection of viruses or diagnostics of virus diseases. Here we show design of a microscope slide-based microarray assay for simultaneous identification of several potato viruses. Different primer pairs were designed or adopted to obtain specific amplicons from six potato viruses: Potato virus A (PVA), Potato virus S (PVS), Potato virus X (PVX), Potato virus Y (PVY), Potato mop-top virus (PMTV) and Potato leaf-roll virus (PLRV). Purified viral DNA probes were spotted on a microscope slide coated with poly-L-lysine. The same primers were used for preparation of fluorochrome-labeled targets. The latter were denatured and hybridized on the microarray slide (chip). An example of simultaneous assay of two pathogens is given and possibilities of practical application of this type of assay are discussed.
- MeSH
- DNA Primers genetics MeSH
- DNA, Viral analysis isolation & purification MeSH
- Plant Diseases virology MeSH
- Potexvirus genetics isolation & purification MeSH
- Potyvirus genetics isolation & purification MeSH
- Plant Viruses genetics isolation & purification MeSH
- Sequence Analysis, DNA MeSH
- Oligonucleotide Array Sequence Analysis methods statistics & numerical data MeSH
- Sequence Homology MeSH
- Sensitivity and Specificity MeSH
- Solanum tuberosum virology MeSH
- Publication type
- Journal Article MeSH
- Evaluation Study MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- DNA Primers MeSH
- DNA, Viral MeSH
This research was focused on a critical assessment of vacuum frying as a technology enabling minimization of acrylamide formation in potato crisps and reducing undesirable chemical changes that occur in frying oil at high temperatures. The potato slices were fried in rapeseed oil under vacuum at 125°C and atmospheric pressure at 165°C. The experiments were performed on two potato varieties, Saturna and Impala. Vacuum frying reduced the formation of acrylamide by 98% and also other Maillard reaction products, specifically alkylpyrazines. Concurrently a lower extent of oxidative changes was observed in the frying oil, while 3-MCPD esters decreased fairly quickly during conventional frying. Sensory characteristics of the vacuum and conventionally fried potato crisps were evaluated by a 23-member panel. The majority of panellists preferred the flavour of 'conventional crisps', while only a few of them appreciated potato-like fresh flavour of 'vacuum crisps' and classified this product as 'tasty'.
- Keywords
- 3-MCPD esters, Acrylamide, Alkyl pyrazines, Conventional frying, Oil oxidation, Potato crisps, Vacuum frying,
- MeSH
- Acrylamide MeSH
- alpha-Chlorohydrin MeSH
- Food Handling * MeSH
- Solanum tuberosum * MeSH
- Vacuum MeSH
- Cooking MeSH
- Hot Temperature MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Acrylamide MeSH
- alpha-Chlorohydrin MeSH
Potato proteins are well known for their nutritional, emulsifying, foaming, gel forming or antioxidant properties that all make from them valuable protein source for food industry. Antifungal, antimicrobial and also antiviral properties, described for potato proteins in the review, enrich the possibilities of potato protein usage. Potato proteins were divided into patatin, protease inhibitors and fraction of other proteins that also included, besides others, proteins involved in potato defence physiology. All these proteins groups provide proteins and peptides with antifungal and/or antimicrobial actions. Patatins, obtained from cultivars with resistance to Phytophthora infestans, were able to inhibit spore germination of this pathogen. Protease inhibitors represent the structurally heterogeneous group with broad range of antifungal and antimicrobial activities. Potato protease inhibitors I and II reduced the growth of Phytophthora infestans, Rhizoctonia solani and Botrytis cinerea or of the fungi of Fusarium genus. Members of Kunitz family (proteins Potide-G, AFP-J, Potamin-1 or PG-2) were able to inhibit serious pathogens such as Staphylococcus aureus, Listeria monocytogenes, Escherichia coli or Candida albicans. Potato snakins, defensins and pseudothionins are discussed for their ability to inhibit serious potato fungi as well as bacterial pathogens. Potato proteins with the ability to inhibit growth of pathogens were used for developing of pathogen-resistant transgenic plants for crop improvement. Incorporation of potato antifungal and antimicrobial proteins in feed and food products or food packages for elimination of hygienically risk pathogens brings new possibility of potato protein usage.
- Keywords
- Antifungal proteins, L., Bioactive proteins, Patatin, Potato defensin, Potato snakins, Potato tubers, Protease inhibitors, Solanum tuberosum,
- MeSH
- Anti-Bacterial Agents chemistry pharmacology MeSH
- Antifungal Agents chemistry pharmacology MeSH
- Bacteria drug effects MeSH
- Candida albicans drug effects MeSH
- Fungicides, Industrial chemistry pharmacology MeSH
- Fungi drug effects MeSH
- Carboxylic Ester Hydrolases chemistry pharmacology MeSH
- Listeria monocytogenes drug effects MeSH
- Peptides chemistry pharmacology MeSH
- Phytophthora drug effects MeSH
- Plant Proteins chemistry pharmacology MeSH
- Solanum tuberosum chemistry MeSH
- Staphylococcus aureus drug effects MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
- Names of Substances
- Anti-Bacterial Agents MeSH
- Antifungal Agents MeSH
- Fungicides, Industrial MeSH
- Carboxylic Ester Hydrolases MeSH
- patatin protein, Solanum tuberosum MeSH Browser
- Peptides MeSH
- Plant Proteins MeSH
Simple and reliable procedure for sample preparation and reverse transcription-polymerase chain reaction (RT-PCR) detection of potato virus A (PVA) is described. PVA-specific primers used in the RT-PCR defined a target sequence of 321 bp and did not produce amplification product(s) with potato virus Y.
Twenty potato virus Y (PVY) isolates were characterized. They represented two strains only, PVY(O) (three isolates) and PVY(N) (17 isolates). However, application of serological and molecular genetic methods led to a more complicated characterization. For example, five isolates induced necrotic symptoms on tobacco plants typical of PVY(N), despite reacting as PVY(O) serologically. Moreover, the PVY isolates were not identical according to molecular genetic properties. Typical PVY(NTN) PCR products were observed for 14 isolates, but five of them (Hr 220-5, Hr 387-7, Nord 242, Syn1Scot, and 41-97) did not produce potato tuber necrotic symptoms in infected cultivars. An immunocapture reverse transcription-polymerase chain reaction (RT-PCR) probing was developed using a set of 24 primer pairs derived from eight regions of the PVY genome. Using this method, five out of seven PVY(NTN) isolates including the Czech standard PVY(NTN) from the potato cv. Nicola were found to be identical. However, two PVY(NTN) isolates and all the other probed PVY samples showed unique patterns, suggesting specific differences at the nucleotide level. This method enabled specific identification of individual isolates variability even within different PVY strains.
- MeSH
- DNA Primers genetics MeSH
- Plant Leaves virology MeSH
- Reverse Transcriptase Polymerase Chain Reaction methods MeSH
- Potyvirus classification genetics isolation & purification MeSH
- Sensitivity and Specificity MeSH
- Serotyping MeSH
- Solanum tuberosum virology MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- DNA Primers MeSH
Coloured-fleshed potatoes of four varieties were used as raw material for coloured flour and fried snack production. The effects of thermal processes traditionally used in dried potato processing and in snack pellet manufacturing on anthocyanin profiles, total polyphenols and antioxidant properties of obtained half- and ready products were studied. There was a significant influence of potato variety on the experimental flour and snack properties. Flours with the highest antioxidant activities were obtained from Salad Blue and Herbie 26 potatoes; however, the flour prepared from the Blue Congo exhibited a much higher total polyphenol and anthocyanin content. Snacks produced with coloured flour had 2-3 times higher antioxidant activities, 40% higher contents of polyphenols, attractive colour and better expansion compared to control samples. The lowest losses of anthocyanins during snack processing were in snacks with flour from the purple-fleshed Blue Congo and red-fleshed Herbie 26.
- Keywords
- Anthocyanins, Antioxidant activity, Coloured potatoes, Polyphenols, Snacks,
- MeSH
- Anthocyanins analysis MeSH
- Antioxidants pharmacology MeSH
- Color MeSH
- Food Handling MeSH
- Flour analysis MeSH
- Snacks * MeSH
- Oxidation-Reduction MeSH
- Polyphenols analysis MeSH
- Solanum tuberosum chemistry MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Anthocyanins MeSH
- Antioxidants MeSH
- Polyphenols MeSH
Potatoes, members of the Solanaceae plant family, contain calystegines, water-soluble nortropane alkaloids, which are biologically active as glycosidase inhibitors. The content of calystegines A(3) and B(2) in different varieties of potato and in various parts of the tubers (whole potato, peel, flesh, and sprouts) were analysed by new capillary zone electrophoresis and capillary isotachophoresis methods and by the routine GC method. The optimized background electrolyte for capillary zone electrophoretic analysis was mixture of 20 mM histidine, 20 mM N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid and 20% (v/v) methanol in demineralized water. Calystegines were detected by indirect UV detection at 210 nm. A clear separation of calystegines from other components of the methanolic sample extract was achieved within 4 min. The electrolytes for isotachophoretic analysis consisted of 5 mM NH(4)OH, 10 mM N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, 0.1% hydroxyethylcellulose and 20% (v/v) methanol in demineralized water (leading) and 5 mM histidine+10 mM acetic acid+20% (v/v) methanol in demineralized water (terminating). Calystegines were separated within 20 min and detected by a conductimeter. Method characteristics of both zone electrophoresis and isotachophoresis, i.e., linearity (10-100 ng/microl and 1-10 ng/microl), accuracy (recovery 96+/-5% and 98+/-4%), intra-assay repeatability (4.2% and 3.5%), and detection limit (3 and 0.4 ng/microl) were evaluated. Simple sample preparation, sufficient sensitivity, speed of analysis, and low running cost are important attributes of the electrophoretic methods. The overall results of electrophoretic methods were comparable with GC.
- MeSH
- Solanaceous Alkaloids analysis MeSH
- Chromatography, Gas MeSH
- Electrophoresis, Capillary methods MeSH
- Nortropanes analysis MeSH
- Solanum tuberosum chemistry MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Comparative Study MeSH
- Names of Substances
- Solanaceous Alkaloids MeSH
- calystegine A3 MeSH Browser
- calystegine B(2) MeSH Browser
- Nortropanes MeSH
The effect of storage conditions on the serological activity of two strains of potato virus S (PVS), Andean and the ordinary, was studied by ELISA. Virus purificates, infected leaves and their homogenates, stored in lyophilized, frozen and dissolved form at various temperatures were tested. Virus purificates were most stable in lyophilized form, their activity decreased after 9 months only by 20-30%. Also non-purified virus was most stable as a lyophilized leaf homogenate, its activity decreased after 12 months by 30%. When lyophilized leaves were stored, the virus activity dropped after 12 months by 45%. Both the Andean and the ordinary strain of PVS behaved similarly during storage under the conditions tested.
Many factors affect successful virus propagation and plant defence responses. Heat shock protein (Hsp) expression after heat shock plays an ambiguous role in viral infection. On the one hand, Hsp70 participates in plant defence response; on the other hand, Hsp70 could interact with viral proteins and facilitate virus propagation. Here, we studied metabolic adaptations of Nicotiana tabacum L. subjected to heat shock (42 °C, 2 h) before or after inoculating the plants with Potato virus Y (potyvirus). RT-qPCR and ELISA were used for potyvirus quantification. Hsp70 and Hsp90 isoforms were analysed by Western blotting. Salicylic, quinic and chlorogenic acid content was determined by LC-MS. The activity of Hatch-Slack enzymes (as markers of potyviral infection in tobacco) and glycosidases was assayed. Application of heat shock before or after inoculation showed accelerated potyviral propagation in comparison with only inoculated plants. Plants exposed to heat shock and concurrently inoculated showed higher potyviral content, higher amount of Hsp70, together with late decline of quinic acid content and low chlorogenic acid content. Spread of potyviral infection correlated with enhanced salicylic acid content and activities of enzymes of the Hatch-Slack cycle, α- and β-galactosidase, α-mannosidase, α-glucosidase and β-N-acetylhexosaminidase. Heat shock proteins accelerate potyviral propagation. The lower weight cytosolic and mitochondrial Hsp70 (~50-75 kDa) persist throughout the viral infection. Also, the plant defense response results in increase of salicylic and chlorogenic acids but decrease of quinic acid content.
- Keywords
- Potato virus Y, Hatch-Slack cycle, Hsp70, Hsp90, glycosidases, heat shock, phenolic acids,
- MeSH
- Potyvirus * MeSH
- HSP70 Heat-Shock Proteins MeSH
- Heat-Shock Response MeSH
- Nicotiana MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- HSP70 Heat-Shock Proteins MeSH
