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R. Rabindran - One of the best experts on this subject based on the ideXlab platform.
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Molecular characterization based on spermidine/putrescine ABC transporter gene of sugarcane grassy shoot (16SrXI), coconut root wilt (16SrXI), Aster Yellows (16SrI) and brinjal little leaf (16SrVI) phytoplasmas
Phytopathogenic Mollicutes, 2014Co-Authors: R. Manimekalai, Roshna Othayoth Mailapravan, Gangaraj Kariyath Palliyath, Smita K. Nair, Rasappa Viswanathan, R. RabindranAbstract:In the present study a molecular characterization of spermidine/putrescine ABC transporter gene fragments from four different phytoplasmas, namely coconut root wilt (16SrXI), sugarcane grassy shoot (16SrXI), Aster Yellows (16srI) and brinjal little leaf (16SrVI) was carried out based on DNA sequencing and in silico methods. Part of the ABC transporter potC and potB gene was employed for actual and virtual RFLP analysis. In a dendrogram, coconut root wilt and sugarcane grassy shoot phytoplasmas clustered together, Aster Yellows clustered with 16SrI group phytoplasmas and brinjal little leaf phytoplasma was separately placed suggesting that clustering based on this gene is congruent with 16S rDNA based phytoplasma differentiation.
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molecular characterization based on spermidine putrescine abc transporter gene of sugarcane grassy shoot 16srxi coconut root wilt 16srxi Aster Yellows 16sri and brinjal little leaf 16srvi phytoplasmas
Phytopathogenic Mollicutes, 2014Co-Authors: R. Manimekalai, Roshna Othayoth Mailapravan, Gangaraj Kariyath Palliyath, Smita K. Nair, Rasappa Viswanathan, R. RabindranAbstract:In the present study a molecular characterization of spermidine/putrescine ABC transporter gene fragments from four different phytoplasmas, namely coconut root wilt (16SrXI), sugarcane grassy shoot (16SrXI), Aster Yellows (16srI) and brinjal little leaf (16SrVI) was carried out based on DNA sequencing and in silico methods. Part of the ABC transporter potC and potB gene was employed for actual and virtual RFLP analysis. In a dendrogram, coconut root wilt and sugarcane grassy shoot phytoplasmas clustered together, Aster Yellows clustered with 16SrI group phytoplasmas and brinjal little leaf phytoplasma was separately placed suggesting that clustering based on this gene is congruent with 16S rDNA based phytoplasma differentiation.
I.-m. Lee - One of the best experts on this subject based on the ideXlab platform.
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Draft genome sequence of the New Jersey Aster Yellows strain of 'Candidatus Phytoplasma Asteris'.
PloS one, 2018Co-Authors: Michael E. Sparks, Kristi D. Bottner-parker, Dawn E. Gundersen-rindal, I.-m. LeeAbstract:The NJAY (New Jersey Aster Yellows) strain of ‘Candidatus Phytoplasma Asteris’ is a significant plant pathogen responsible for causing severe lettuce Yellows in the U.S. state of New Jersey. A draft genome sequence was prepared for this organism. A total of 177,847 reads were assembled into 75 contigs > 518 bp with a total base value of 652,092 and an overall [G+C] content of 27.1%. A total of 733 protein coding genes were identified. This Whole Genome Shotgun project has been deposited at DDBJ/ENA/GenBank under the accession MAPF00000000. This draft genome was used for genome- and gene-based comparative phylogenetic analyses with other phytoplasmas, including the closely related ‘Ca. Phytoplasma Asteris’ strain, Aster Yellows witches’- broom (AY-WB). NJAY and AY-WB exhibit approximately 0.5% dissimilarity at the nucleotide level among their shared genomic segments. Evidence indicated that NJAY harbors four plasmids homologous to those known to encode pathogenicity determinants in AY-WB, as well as a chromosome-encoded mobile unit. Apparent NJAY orthologs to the important AY-WB virulence factors, SAP11 and SAP54, were identified. A number of secreted proteins, both membrane-bound and soluble, were encoded, with many bearing similarity to known AY-WB effector molecules and others representing possible secreted proteins that may be novel to the NJAY lineage.
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Aster Yellows group (16SrI), subgroups 16SrI-A and 16SrI-B, phytoplasmas associated with lettuce Yellows in Texas
New Disease Reports, 2014Co-Authors: I.-m. Lee, R. E. Davis, K.d. Bottner-parker, Yan Zhao, M.c. BlackAbstract:Lettuce ( Lactuca sativa ) is an important vegetable crop grown in the United States. Lettuce Yellows (previously termed lettuce Aster Yellows) is a devastating disease commonly found in lettuce fields and causes significant economic loss to…
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First Report of Aster Yellows Phytoplasma in Alfalfa
Plant disease, 1999Co-Authors: R. D. Peters, M. E. Lee, Craig R. Grau, S. J. Driscoll, R. M. Winberg, N. C. Kurtzweil, L. A. Lukaesko, I.-m. LeeAbstract:Samples of alfalfa (Medicago sativa L.) leaves and stems showing symptoms of inter-veinal chlorosis and purpling, commonly associated with insect feeding, were collected from 8 sites in central and southern Wisconsin in autumn of 1998. Samples were frozen within 24 h of collection. Approximately 0.3 g of plant tissue from each sample was used for total DNA extraction according to the protocol of Zhang et al. (4), with minor modifications in grinding procedures and reagent volumes to optimize results. Nested polymerase chain reaction (PCR) was carried out by amplification of 16S rDNA with the universal primer pairs R16mF2/R16mR1 followed by R16F2n/R16R2 as described by Gunder-sen and Lee (1). Undiluted total sample DNA was used for the first amplification; PCR products were diluted (1:30) in sterile water prior to final amplification. Alfalfa DNA and sterile water were used as negative controls; DNA from phytoplasma causing X-disease in peach (CX) served as a positive control. Fragments of 16S rDNA from putative phytoplasmas amplified by PCR with the primer pair R16F2n/R16R2 were characterized by restriction endonuclease digestion (3). The resulting restriction fragment length polymorphism (RFLP) patterns were compared with patterns for known phytoplasmas described by Lee et al. (3). Products of nested PCR were also purified and sequenced with primers R16F2n/R16R2 and an automated DNA sequencer (ABI 377XL; C. Nicolet, Biotechnology Center, University of Wisconsin-Madison). Of 51 samples of alfalfa assessed, one sample from Evansville, WI, yielded a nested PCR product of the appropriate size (1.2 kb), indicating the presence of phytoplasma. Digestion of this product with various restriction enzymes produced RFLP patterns that were identical to those for phytoplasmas in the Aster Yellows phytoplasma subgroup 16SrI-A (3). Alignment of the DNA sequence of the nested PCR product from the positive sample with sequences found in the GenBank sequence data base (National Center for Biotechnology Information, Bethesda, MD) with the BLAST sequence similarity function confirmed this result. Although other phytoplasma strains (particularly those causing witches'-broom) have been reported to infect alfalfa (2), this is the first report of the presence of the Aster Yellows phytoplasma in the alfalfa crop. Vectors involved in transmission and the potential agronomic impacts of Aster Yellows phytoplasma in alfalfa are topics of current investigation. References: (1) D. E. Gundersen and I.-M. Lee. Phytopathol. Mediterr. 35:144, 1996. (2) A.-H. Khadhair et al. Microbiol. Res. 152:269, 1997. (3) I.-M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998. (4) Y.-P. Zhang et al. J. Virol. Methods 71:45, 1998.
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Differentiation of strains in the Aster Yellows mycoplasmalike organism strain cluster by serological assay with monoclonal antibodies
Plant Disease, 1993Co-Authors: I.-m. Lee, Robert E. Davis, H. T. HsuAbstract:Monoclonal antibodies (MAbs) raised against the tomato big bud (BB) mycoplasmalike organism (MLO), a member of the Aster Yellows (AY) MLO strain cluster, were employed in dot immunobinding assays. The MAbs reacted only with strains in the AY MLO cluster, and not with any of several other MLOs not affiliated with the AY MLO strain cluster. However, reactions with MLOs in the AY cluster varied by strain. All MAbs reacted with BB and several MLO strains previously termed «Aster Yellows,» including NAY (eAstern AY), OKAY1 (Oklahoma strain), NJAY (New Jersey strain), and AY27 (Alberta strain); but none of the MAbs reacted with certain other strains of AY MLO, including strains termed SAYS (western AY), OKAYS (Oklahoma strain), NYAY (New York strain), and MNAY (Minnesota strain)
R. Manimekalai - One of the best experts on this subject based on the ideXlab platform.
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Molecular characterization based on spermidine/putrescine ABC transporter gene of sugarcane grassy shoot (16SrXI), coconut root wilt (16SrXI), Aster Yellows (16SrI) and brinjal little leaf (16SrVI) phytoplasmas
Phytopathogenic Mollicutes, 2014Co-Authors: R. Manimekalai, Roshna Othayoth Mailapravan, Gangaraj Kariyath Palliyath, Smita K. Nair, Rasappa Viswanathan, R. RabindranAbstract:In the present study a molecular characterization of spermidine/putrescine ABC transporter gene fragments from four different phytoplasmas, namely coconut root wilt (16SrXI), sugarcane grassy shoot (16SrXI), Aster Yellows (16srI) and brinjal little leaf (16SrVI) was carried out based on DNA sequencing and in silico methods. Part of the ABC transporter potC and potB gene was employed for actual and virtual RFLP analysis. In a dendrogram, coconut root wilt and sugarcane grassy shoot phytoplasmas clustered together, Aster Yellows clustered with 16SrI group phytoplasmas and brinjal little leaf phytoplasma was separately placed suggesting that clustering based on this gene is congruent with 16S rDNA based phytoplasma differentiation.
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molecular characterization based on spermidine putrescine abc transporter gene of sugarcane grassy shoot 16srxi coconut root wilt 16srxi Aster Yellows 16sri and brinjal little leaf 16srvi phytoplasmas
Phytopathogenic Mollicutes, 2014Co-Authors: R. Manimekalai, Roshna Othayoth Mailapravan, Gangaraj Kariyath Palliyath, Smita K. Nair, Rasappa Viswanathan, R. RabindranAbstract:In the present study a molecular characterization of spermidine/putrescine ABC transporter gene fragments from four different phytoplasmas, namely coconut root wilt (16SrXI), sugarcane grassy shoot (16SrXI), Aster Yellows (16srI) and brinjal little leaf (16SrVI) was carried out based on DNA sequencing and in silico methods. Part of the ABC transporter potC and potB gene was employed for actual and virtual RFLP analysis. In a dendrogram, coconut root wilt and sugarcane grassy shoot phytoplasmas clustered together, Aster Yellows clustered with 16SrI group phytoplasmas and brinjal little leaf phytoplasma was separately placed suggesting that clustering based on this gene is congruent with 16S rDNA based phytoplasma differentiation.
Jana Fránová - One of the best experts on this subject based on the ideXlab platform.
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multigene sequence analysis of Aster Yellows phytoplasma associated with primrose Yellows
Journal of Phytopathology, 2016Co-Authors: Jana Fránová, Jaroslava Přibylová, Igor Koloniuk, Kateřina PodrabskaAbstract:Primula acaulis (L.) Hill. plants showing stunting, leaf-yellowing and virescence were first discovered in the Czech Republic. Polymerase chain reactions with subsequent restriction fragment length polymorphism analyses and sequencing enabled classification of the detected phytoplasmas into the Aster Yellows group, ribosomal subgroup 16SrI-B, tufI-B, rpI-B, groELIB-III and SecY-IB subgroups. Phylogeny of the 16S rRNA gene sequences as well as sequence analysis of several chromosomal regions, such as the 16S-23S ribosomal operon, ribosomal proteins, spc ribosomal protein operon, genes for elongation factor EF-Tu, molecular chaperonin large subunit GroEL, immunodominant membrane protein, ribosome recycling factor, urydilate kinase, ATP- and Zn2+-dependent proteases not only confirmed its affiliation with the ‘Candidatus Phytoplasma Asteris’ species but also enabled its detailed molecular characterization. The less researched regions of phytoplasma genome (amp, adk, hflB, pyrH-frr genes) could be valuable as additional markers for phytoplasma through differentiation especially within the 16SrI-B ribosomal subgroup.
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molecular characterization of Aster Yellows subgroup 16sri b phytoplasma in verbena hybrida
Journal of Phytopathology, 2015Co-Authors: Jaroslava Přibylová, Karel Petrzik, Jana FránováAbstract:Symptoms resembling phytoplasma disease were observed on Verbena × hybrida in Alanya, Turkey, during October 2013. Infected plants were growing as perennials in a flower border and showed symptoms of discoloured flowers, poor flower clusters, inflorescences with a small number of developed flowers and thickened fruit stalks. Electron microscopy examination of the ultra-thin sections revealed polymorphic bodies in the phloem tissue of leaf midribs. The phytoplasma aetiology of this disease was confirmed by polymerase chain reaction of the 16S rRNA gene, the 16–23S rRNA intergenic spacer region and the start of the 23S rRNA gene using universal phytoplasma-specific primer pair P1A/P7A, two ribosomal protein (rp) genes (rpl22 and rps3) (the group-specific primer pair rp(I)F1A/rp(I)R1A) and the Tuf gene (group-specific fTufAy/rTufAy primers) generating amplicons of 1.8 kbp, 1.2 kbp and 940 bp, respectively. Comparison of the amplified sequences with those available in GenBank allowed classification of the phytoplasma into Aster Yellows subgroups 16SrI-B, rpI-B and tufI-B. This is the first report about molecular detection and identification of natural infection of the genus Verbena by phytoplasma and occurrence of the Aster Yellows group phytoplasma on an ornamental plant in Turkey.
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Molecular Characterization of Aster Yellows Subgroup 16SrI‐B Phytoplasma in Verbena × hybrida
Journal of Phytopathology, 2014Co-Authors: Jaroslava Přibylová, Jana Fránová, Karel Petrzik, Josef ŠpakAbstract:Symptoms resembling phytoplasma disease were observed on Verbena × hybrida in Alanya, Turkey, during October 2013. Infected plants were growing as perennials in a flower border and showed symptoms of discoloured flowers, poor flower clusters, inflorescences with a small number of developed flowers and thickened fruit stalks. Electron microscopy examination of the ultra-thin sections revealed polymorphic bodies in the phloem tissue of leaf midribs. The phytoplasma aetiology of this disease was confirmed by polymerase chain reaction of the 16S rRNA gene, the 16–23S rRNA intergenic spacer region and the start of the 23S rRNA gene using universal phytoplasma-specific primer pair P1A/P7A, two ribosomal protein (rp) genes (rpl22 and rps3) (the group-specific primer pair rp(I)F1A/rp(I)R1A) and the Tuf gene (group-specific fTufAy/rTufAy primers) generating amplicons of 1.8 kbp, 1.2 kbp and 940 bp, respectively. Comparison of the amplified sequences with those available in GenBank allowed classification of the phytoplasma into Aster Yellows subgroups 16SrI-B, rpI-B and tufI-B. This is the first report about molecular detection and identification of natural infection of the genus Verbena by phytoplasma and occurrence of the Aster Yellows group phytoplasma on an ornamental plant in Turkey.
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Aster Yellows subgroup 16sri c phytoplasma in rhododendron hybridum
Journal of Phytopathology, 2013Co-Authors: Jaroslava Přibylová, Jana FránováAbstract:Symptoms of unknown aetiology on Rhododendron hybridum cv. Cunningham's White were observed in the Czech Republic in 2010. The infected plant had malformed leaves, with irregular shaped edges, mosaic, leaf tip necrosis and multiple axillary shoots with smaller leaves. Transmission electron microscopy showed phytoplasma-like bodies in phloem cells of the symptomatic plant. Phytoplasma presence was confirmed by polymerase chain reaction using phytoplasma-specific, universal and group-specific primer pairs. Restriction fragment length polymorphism analysis of 16S rDNA enabled classification of the detected phytoplasma into the Aster Yellows subgroup I-C. Sequence analysis of the 16S-23S ribosomal operon of the amplified phytoplasma genome from the infected rhododendron plant (1724 bp) confirmed the closest relationship with the Czech Echinacea purpurea phyllody phytoplasma. These data suggest Rhododendron hybridum is a new host for the Aster Yellows phytoplasma subgroup 16SrI-C in the Czech Republic and worldwide.
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Aster Yellows Subgroup 16SrI‐C Phytoplasma in Rhododendron hybridum
Journal of Phytopathology, 2013Co-Authors: Jaroslava Přibylová, Josef Špak, Jana FránováAbstract:Symptoms of unknown aetiology on Rhododendron hybridum cv. Cunningham's White were observed in the Czech Republic in 2010. The infected plant had malformed leaves, with irregular shaped edges, mosaic, leaf tip necrosis and multiple axillary shoots with smaller leaves. Transmission electron microscopy showed phytoplasma-like bodies in phloem cells of the symptomatic plant. Phytoplasma presence was confirmed by polymerase chain reaction using phytoplasma-specific, universal and group-specific primer pairs. Restriction fragment length polymorphism analysis of 16S rDNA enabled classification of the detected phytoplasma into the Aster Yellows subgroup I-C. Sequence analysis of the 16S-23S ribosomal operon of the amplified phytoplasma genome from the infected rhododendron plant (1724 bp) confirmed the closest relationship with the Czech Echinacea purpurea phyllody phytoplasma. These data suggest Rhododendron hybridum is a new host for the Aster Yellows phytoplasma subgroup 16SrI-C in the Czech Republic and worldwide.
Jaroslava Přibylová - One of the best experts on this subject based on the ideXlab platform.
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multigene sequence analysis of Aster Yellows phytoplasma associated with primrose Yellows
Journal of Phytopathology, 2016Co-Authors: Jana Fránová, Jaroslava Přibylová, Igor Koloniuk, Kateřina PodrabskaAbstract:Primula acaulis (L.) Hill. plants showing stunting, leaf-yellowing and virescence were first discovered in the Czech Republic. Polymerase chain reactions with subsequent restriction fragment length polymorphism analyses and sequencing enabled classification of the detected phytoplasmas into the Aster Yellows group, ribosomal subgroup 16SrI-B, tufI-B, rpI-B, groELIB-III and SecY-IB subgroups. Phylogeny of the 16S rRNA gene sequences as well as sequence analysis of several chromosomal regions, such as the 16S-23S ribosomal operon, ribosomal proteins, spc ribosomal protein operon, genes for elongation factor EF-Tu, molecular chaperonin large subunit GroEL, immunodominant membrane protein, ribosome recycling factor, urydilate kinase, ATP- and Zn2+-dependent proteases not only confirmed its affiliation with the ‘Candidatus Phytoplasma Asteris’ species but also enabled its detailed molecular characterization. The less researched regions of phytoplasma genome (amp, adk, hflB, pyrH-frr genes) could be valuable as additional markers for phytoplasma through differentiation especially within the 16SrI-B ribosomal subgroup.
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molecular characterization of Aster Yellows subgroup 16sri b phytoplasma in verbena hybrida
Journal of Phytopathology, 2015Co-Authors: Jaroslava Přibylová, Karel Petrzik, Jana FránováAbstract:Symptoms resembling phytoplasma disease were observed on Verbena × hybrida in Alanya, Turkey, during October 2013. Infected plants were growing as perennials in a flower border and showed symptoms of discoloured flowers, poor flower clusters, inflorescences with a small number of developed flowers and thickened fruit stalks. Electron microscopy examination of the ultra-thin sections revealed polymorphic bodies in the phloem tissue of leaf midribs. The phytoplasma aetiology of this disease was confirmed by polymerase chain reaction of the 16S rRNA gene, the 16–23S rRNA intergenic spacer region and the start of the 23S rRNA gene using universal phytoplasma-specific primer pair P1A/P7A, two ribosomal protein (rp) genes (rpl22 and rps3) (the group-specific primer pair rp(I)F1A/rp(I)R1A) and the Tuf gene (group-specific fTufAy/rTufAy primers) generating amplicons of 1.8 kbp, 1.2 kbp and 940 bp, respectively. Comparison of the amplified sequences with those available in GenBank allowed classification of the phytoplasma into Aster Yellows subgroups 16SrI-B, rpI-B and tufI-B. This is the first report about molecular detection and identification of natural infection of the genus Verbena by phytoplasma and occurrence of the Aster Yellows group phytoplasma on an ornamental plant in Turkey.
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Molecular Characterization of Aster Yellows Subgroup 16SrI‐B Phytoplasma in Verbena × hybrida
Journal of Phytopathology, 2014Co-Authors: Jaroslava Přibylová, Jana Fránová, Karel Petrzik, Josef ŠpakAbstract:Symptoms resembling phytoplasma disease were observed on Verbena × hybrida in Alanya, Turkey, during October 2013. Infected plants were growing as perennials in a flower border and showed symptoms of discoloured flowers, poor flower clusters, inflorescences with a small number of developed flowers and thickened fruit stalks. Electron microscopy examination of the ultra-thin sections revealed polymorphic bodies in the phloem tissue of leaf midribs. The phytoplasma aetiology of this disease was confirmed by polymerase chain reaction of the 16S rRNA gene, the 16–23S rRNA intergenic spacer region and the start of the 23S rRNA gene using universal phytoplasma-specific primer pair P1A/P7A, two ribosomal protein (rp) genes (rpl22 and rps3) (the group-specific primer pair rp(I)F1A/rp(I)R1A) and the Tuf gene (group-specific fTufAy/rTufAy primers) generating amplicons of 1.8 kbp, 1.2 kbp and 940 bp, respectively. Comparison of the amplified sequences with those available in GenBank allowed classification of the phytoplasma into Aster Yellows subgroups 16SrI-B, rpI-B and tufI-B. This is the first report about molecular detection and identification of natural infection of the genus Verbena by phytoplasma and occurrence of the Aster Yellows group phytoplasma on an ornamental plant in Turkey.
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Aster Yellows subgroup 16sri c phytoplasma in rhododendron hybridum
Journal of Phytopathology, 2013Co-Authors: Jaroslava Přibylová, Jana FránováAbstract:Symptoms of unknown aetiology on Rhododendron hybridum cv. Cunningham's White were observed in the Czech Republic in 2010. The infected plant had malformed leaves, with irregular shaped edges, mosaic, leaf tip necrosis and multiple axillary shoots with smaller leaves. Transmission electron microscopy showed phytoplasma-like bodies in phloem cells of the symptomatic plant. Phytoplasma presence was confirmed by polymerase chain reaction using phytoplasma-specific, universal and group-specific primer pairs. Restriction fragment length polymorphism analysis of 16S rDNA enabled classification of the detected phytoplasma into the Aster Yellows subgroup I-C. Sequence analysis of the 16S-23S ribosomal operon of the amplified phytoplasma genome from the infected rhododendron plant (1724 bp) confirmed the closest relationship with the Czech Echinacea purpurea phyllody phytoplasma. These data suggest Rhododendron hybridum is a new host for the Aster Yellows phytoplasma subgroup 16SrI-C in the Czech Republic and worldwide.
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Aster Yellows Subgroup 16SrI‐C Phytoplasma in Rhododendron hybridum
Journal of Phytopathology, 2013Co-Authors: Jaroslava Přibylová, Josef Špak, Jana FránováAbstract:Symptoms of unknown aetiology on Rhododendron hybridum cv. Cunningham's White were observed in the Czech Republic in 2010. The infected plant had malformed leaves, with irregular shaped edges, mosaic, leaf tip necrosis and multiple axillary shoots with smaller leaves. Transmission electron microscopy showed phytoplasma-like bodies in phloem cells of the symptomatic plant. Phytoplasma presence was confirmed by polymerase chain reaction using phytoplasma-specific, universal and group-specific primer pairs. Restriction fragment length polymorphism analysis of 16S rDNA enabled classification of the detected phytoplasma into the Aster Yellows subgroup I-C. Sequence analysis of the 16S-23S ribosomal operon of the amplified phytoplasma genome from the infected rhododendron plant (1724 bp) confirmed the closest relationship with the Czech Echinacea purpurea phyllody phytoplasma. These data suggest Rhododendron hybridum is a new host for the Aster Yellows phytoplasma subgroup 16SrI-C in the Czech Republic and worldwide.
