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V. Špaková - One of the best experts on this subject based on the ideXlab platform.

  • Sequence comparison and transmission of BlackCurrant reversion virus isolates in black, Red and white Currants with black Currant reversion disease and full blossom disease symptoms
    European Journal of Plant Pathology, 2008
    Co-Authors: J. Přibylová, D. Kubelková, J. Špak, K. Petrzik, V. Špaková
    Abstract:

    We collected samples from black, Red and white Currants showing symptoms of blackCurrant reversion disease (BRD) and full blossom disease (FBD), cultivated in the Czech Republic. BlackCurrant reversion virus (BRV) was detected in all symptomatic plants. After amplification, a substantial part of the 3′ non-translated region (3′-NTR) of RNA2 of 15 new isolates of BRV was sequenced and compaRed with sequences available in the literature and GenBank. We did not find significant sequence diversity among isolates associated with either FBD or BRD. BRV was graft-transmitted from FBD infected Red Currant to black Currant where symptoms of BRD were observed. Further sequence analysis of BRV isolates resulted in a phylogenetic tree with four branches, each consisting of six to nine isolates. No correlation with geographic origin was visible on the tree as isolates from various countries occurRed in all four branches. We also found no correlation between the host and the topology of the tree: most of black Currant isolates occurRed in branches 3 and 4, but also occurRed in branches 1 and 2. Only one white Currant and one Red Currant isolate occurRed in branches 3 and 4, respectively. The sequence identity of the Czech isolates in this region ranged from 91.9 to 99.8%. The 17 plant species growing within and in the close vicinity of the BRD-infested plantation were tested negative for BRV by RT-PCR as natural hosts of BRV. BRV was successfully transmitted by mechanical inoculation from black Currant to Nicotiana occidentalis and N. tabacum cv. Xanthi, the latter being a new host for BRV. The infection was confirmed by PCR and sequencing.

  • Occurrence, symptom variation and yield loss caused by full blossom disease in Red and white Currants in the Czech Republic
    Crop Protection, 2006
    Co-Authors: Milan Navrátil, Jaroslava Přibylová, R. Karešová, P. Válová, J. Kučerová, D. Kubelková, R. Fialová, V. Špaková
    Abstract:

    Abstract Full blossom disease (FBD) was found at 11 of 19 monitoRed locations in the Czech Republic. Six cultivars of white Currant and 26 cultivars of Red Currant with characteristic symptoms of the disease were found in germplasm collections, propagation material and commercial plantations. The incidence of the disease varied from 1% to 70% of infected bushes in different cultivars and locations. Similarly, the intensity of symptoms in the field observed between 1999 and 2004 varied from a few malformed flowers up to a massive occurrence of such flowers on whole branches. Yield losses of up to 70% were recorded in severely infected bushes of Red Currant Vitan and fruit quality was poor. Infected seedlings seem to have been the major source of spread of the disease in the last two decades. The presence of both phytoplasma and BRV was confirmed in FBD infected bushes.

Josef Špak - One of the best experts on this subject based on the ideXlab platform.

  • Molecular characterization of a novel capillovirus from Red Currant.
    Archives of Virology, 2016
    Co-Authors: Karel Petrzik, Jaroslava Přibylová, Igor Koloniuk, Josef Špak
    Abstract:

    The complete nucleotide sequence of a novel virus from Red Currant, provisionally named Currant virus A (CuVA), was determined. The genome is 7925 nucleotides long and has a 3'-poly(A) tail. The genome organization with two overlapping open reading frames is similar to that of capilloviruses, but the CuVA genome is about 600 nucleotides longer than that of the longest known capillovirus, cherry virus A. The RNA is pRedicted to encode a polyprotein with domains of methyltransferase, 2OG-Fe(II) oxygenase, papain-like protease, RNA helicase, RdRp, and capsid protein. Phylogenetic analysis confirms that CuVA is a new and distinct member of the genus Capillovirus.

  • Cytokinin, auxin, and abscisic acid dynamics during flower development in white and Red Currants infected with BlackCurrant reversion virus
    Physiological and Molecular Plant Pathology, 2008
    Co-Authors: Alena Gaudinová, Josef Špak, D. Kubelková, Jiří Malbeck, Petre I. Dobrev, Radomira Vankova
    Abstract:

    Abstract BlackCurrant reversion virus (BRV) infection, characteristic by flower malformation, resulted at the early flower stage in elevated levels of bioactive cytokinins and their biosynthetic precursors in flowers of white Currant ‘Blanka’ and Red Currant ‘Vitan’. In healthy flowers, flower-to-berry transition was accompanied by an increase in bioactive cytokinins that was not observed in infected flowers, which were incapable of further development. Auxin levels increased during flower development, in ‘Vitan’ only in flowers with normal morphology (both healthy and infected). BRV infection did not have a significant effect on cytokinin or auxin levels in the leaves of either cultivar, it coincided with a mild elevation in the content of abscisic acid in the flowers of both cultivars.

D. Kubelková - One of the best experts on this subject based on the ideXlab platform.

  • Sequence comparison and transmission of BlackCurrant reversion virus isolates in black, Red and white Currants with black Currant reversion disease and full blossom disease symptoms
    European Journal of Plant Pathology, 2008
    Co-Authors: J. Přibylová, D. Kubelková, J. Špak, K. Petrzik, V. Špaková
    Abstract:

    We collected samples from black, Red and white Currants showing symptoms of blackCurrant reversion disease (BRD) and full blossom disease (FBD), cultivated in the Czech Republic. BlackCurrant reversion virus (BRV) was detected in all symptomatic plants. After amplification, a substantial part of the 3′ non-translated region (3′-NTR) of RNA2 of 15 new isolates of BRV was sequenced and compaRed with sequences available in the literature and GenBank. We did not find significant sequence diversity among isolates associated with either FBD or BRD. BRV was graft-transmitted from FBD infected Red Currant to black Currant where symptoms of BRD were observed. Further sequence analysis of BRV isolates resulted in a phylogenetic tree with four branches, each consisting of six to nine isolates. No correlation with geographic origin was visible on the tree as isolates from various countries occurRed in all four branches. We also found no correlation between the host and the topology of the tree: most of black Currant isolates occurRed in branches 3 and 4, but also occurRed in branches 1 and 2. Only one white Currant and one Red Currant isolate occurRed in branches 3 and 4, respectively. The sequence identity of the Czech isolates in this region ranged from 91.9 to 99.8%. The 17 plant species growing within and in the close vicinity of the BRD-infested plantation were tested negative for BRV by RT-PCR as natural hosts of BRV. BRV was successfully transmitted by mechanical inoculation from black Currant to Nicotiana occidentalis and N. tabacum cv. Xanthi, the latter being a new host for BRV. The infection was confirmed by PCR and sequencing.

  • Cytokinin, auxin, and abscisic acid dynamics during flower development in white and Red Currants infected with BlackCurrant reversion virus
    Physiological and Molecular Plant Pathology, 2008
    Co-Authors: Alena Gaudinová, Josef Špak, D. Kubelková, Jiří Malbeck, Petre I. Dobrev, Radomira Vankova
    Abstract:

    Abstract BlackCurrant reversion virus (BRV) infection, characteristic by flower malformation, resulted at the early flower stage in elevated levels of bioactive cytokinins and their biosynthetic precursors in flowers of white Currant ‘Blanka’ and Red Currant ‘Vitan’. In healthy flowers, flower-to-berry transition was accompanied by an increase in bioactive cytokinins that was not observed in infected flowers, which were incapable of further development. Auxin levels increased during flower development, in ‘Vitan’ only in flowers with normal morphology (both healthy and infected). BRV infection did not have a significant effect on cytokinin or auxin levels in the leaves of either cultivar, it coincided with a mild elevation in the content of abscisic acid in the flowers of both cultivars.

  • Occurrence, symptom variation and yield loss caused by full blossom disease in Red and white Currants in the Czech Republic
    Crop Protection, 2006
    Co-Authors: Milan Navrátil, Jaroslava Přibylová, R. Karešová, P. Válová, J. Kučerová, D. Kubelková, R. Fialová, V. Špaková
    Abstract:

    Abstract Full blossom disease (FBD) was found at 11 of 19 monitoRed locations in the Czech Republic. Six cultivars of white Currant and 26 cultivars of Red Currant with characteristic symptoms of the disease were found in germplasm collections, propagation material and commercial plantations. The incidence of the disease varied from 1% to 70% of infected bushes in different cultivars and locations. Similarly, the intensity of symptoms in the field observed between 1999 and 2004 varied from a few malformed flowers up to a massive occurrence of such flowers on whole branches. Yield losses of up to 70% were recorded in severely infected bushes of Red Currant Vitan and fruit quality was poor. Infected seedlings seem to have been the major source of spread of the disease in the last two decades. The presence of both phytoplasma and BRV was confirmed in FBD infected bushes.

Dragan Radivojević - One of the best experts on this subject based on the ideXlab platform.

  • Biochemical Properties of Red Currant Varieties in Relation to Storage
    Plant Foods for Human Nutrition, 2010
    Co-Authors: Boban Djordjević, Katarina Šavikin, Gordana Zdunić, Teodora Janković, Todor Vulić, Čedo Oparnica, Dragan Radivojević
    Abstract:

    Eleven Red Currant varieties ( Ribes rubrum L.) cultuRed in Serbia were evaluated for some of their biochemical properties such as total phenolics, anthocyanins, ascorbic acid, invert sugar, soluble solid content, and acidity. The average amount of ascorbic acid varied from 50.5–71.6 mg/100 g FW, while concentration of invert sugars ranged from 6.0%–9.0%. The highest amounts of total phenolics and anthocyanins were detected in variety Redpoll (153.4 mg GAE/100 g FW and 19.3 mg/100 g, respectively). Red Currants were processed to juice, and the phenolic and anthocyanin contents changed as a result of processing. Berries and juices were long-term stoRed at −18 °C and changes in phytochemicals were monitoRed. In berries, storage caused the decrease of ascorbic acid content up to 49%, and a general Reduction of total phenolics was also noticed. In juices, total phenolics content increased after one year of storage. In both berries and juices total anthocyanins increased during storage by up to 85% and 50%, respectively. This study demonstrates that certain varieties, namely Redpoll, Jonkheer and London Market are good source of phytochemicals, retaining the nutritional value during processing and storage.

Lavecchia Roberto - One of the best experts on this subject based on the ideXlab platform.

  • Green synthesis of silver nanoparticles using bilberry and Red Currant waste extracts
    'MDPI AG', 2019
    Co-Authors: Zuorro Antonio, Iannone Annalaura, Natali Stefano, Lavecchia Roberto
    Abstract:

    The production of silver nanoparticles (Ag-NPs) from bilberry waste (BW) and Red Currant waste (RCW) extracts was studied. Red fruit extracts were obtained by treating BW and RCW with aqueous ethanol (50% v/v) at 40 °C. The formation of nanoparticles was monitoRed spectrophotometrically by measuring the intensity of the surface plasmon resonance band (SPR) of silver. The effects of temperature (20–60 °C) and pH (8–12) on the reaction kinetics and on the properties of Ag-NPs were investigated. Characterization by XRD and DLS techniques showed that Ag-NPs were highly crystalline, with a face-centeRed cubic structure and a hydrodynamic diameter of 25–65 nm. The zeta potential was in the range of –35.6 to –20.5 mV. Nanoparticles obtained from BW were slightly smaller and more stable than those from RCW. A kinetic analysis by the initial-rate method showed that there was an optimum pH, around 11, for the production of Ag-NPs. Overall, the results obtained suggest that BW and RCW can be advantageously used as a source of Reducing and stabilizing agents for the green synthesis of Ag-NPs