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Levente Kiss - One of the best experts on this subject based on the ideXlab platform.
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Australia: A continent without native powdery Mildews?
2019Co-Authors: Levente Kiss, Niloofar Vaghefi, Kaylene Bransgrove, John Dearnaley, Yu Pei Tan, Craig Marston, Roger G. Shivas, Susuma TakamatsuAbstract:In contrast to Eurasia and North America, the powdery Mildews (Ascomycota, Erysiphales) are largely understudied in Australia. There are over 900 species known globally, with less than 50 recorded from Australia. Some of these records are doubtful as the identifications were presumptive, being based on host plant-pathogen lists from overseas. Australian herbaria contain many undetermined powdery Mildew specimens and an outdated nomenclature is still in use. The Department of Agriculture-sponsored Modern Diagnostics Project identified the Erysiphales as a diagnostic gap that was addressed by a 5-day workshop in 2018. This resulted in (i) an up-to-date list of all the taxa that have been identified in Australia based on published DNA barcode sequences prior to the workshop; (ii) precise identification of 117 specimens freshly collected from across the country; and (iii) precise identification of 30 herbarium specimens collected between 1975 and 2013. Identifications were done based on both morphology and DNA barcodes. Altogether, 39 species representing 10 genera were confirmed in Australia, including two genera and ten species newly recorded during the project. In Eurasia and North America the number of powdery Mildew species is more than 10 time greater. Interestingly, powdery Mildew infections have been recorded on only eight native Australian plant species in the genera Acacia, Acalypha, Eucalyptus, Ixodia, Jagera, Senecio and Trema. All but one of these infections were caused by polyphagous species that infect many other host plants both overseas and in Australia. The data indicates that (i) the native Australian vegetation may have evolved without being exposed to any native powdery Mildews; and (ii) all the species of the Erysiphales that are known to occur in Australia may have been introduced since the European colonisation of the continent.
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first report of oidium longipes as the causal agent of petunia powdery Mildew in the united kingdom
Plant Disease, 2011Co-Authors: Levente Kiss, Zsolt BereczkyAbstract:In autumn 2009, during a survey of powdery Mildews of solanaceous plants in the United Kingdom, petunia (Petunia × hybrida) plants showing typical symptoms of powdery Mildew infections were repeatedly collected in East Malling, Rochester, and Sandringham, UK. Leaves, stems, and petals of the collected plants, grown as outdoor ornamentals, were covered by dense, sporulating, white mycelium. Conidia were ellipsoid-cylindrical, measured 20 to 30 × 10 to 15 μm, and were produced in chains. Germ tubes arose from the ends of conidia and terminated in simple, unlobed apices. Some of the conidiophores were extremely long, up to 250 μm, because the second or third cell, or sometimes the foot cell, was up to 105 to 170 μm long. Other conidiophores were shorter, with no exceptionally long cells, but all of them exhibited a few characteristics in common: their width increased from base to top, sometimes enlarging considerably at a particular point of the foot cell, and basal septa were usually located 7 to 30 μm from...
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oidium longipes a new powdery Mildew fungus on petunia in the usa a potential threat to ornamental and vegetable solanaceous crops
Plant Disease, 2008Co-Authors: Levente Kiss, Tunde Jankovics, Gabor M Kovacs, Margery L DaughtreyAbstract:This is the first North American report of Oidium longipes, an anamorphic powdery Mildew species described recently in Europe. It was found on vegetatively propagated petunia grown in a commercial greenhouse in New Jersey, USA, where it caused a rapidly spreading disease. The pathogen might have originated offshore and may have already been distributed in the United States through horticultural trade. During field surveys in Europe, it was found on petunia in Hungary and Austria as well; this is the first report of O. longipes from these two countries. A detailed light microscopy study of American and European specimens of O. longipes, including freshly collected samples and authentic herbarium specimens, revealed that its conidiophore morphology is more variable than illustrated in the original species description or in subsequent works. Microcycle conidiation, a process not yet known to occur in powdery Mildews, was repeatedly observed in O. longipes. The rDNA internal transcribed spacer (ITS) sequences were identical in colonies containing different conidiophore types as well as in a total of five specimens collected from petunia in the United States, Austria, Hungary, Germany, and Switzerland. A phylogenetic analysis of the ITS sequences revealed that the closest known relative of O. longipes is O. lycopersici, known to infect tomato only in Australia. Cross-inoculation tests showed that O. longipes from petunia heavily infected tobacco cv. Xanthi, while the tomato and eggplant cultivars tested were moderately susceptible to this pathogen. These results indicate that its spread represents a potential danger to a number of solanaceous crops. Our ad hoc field surveys conducted in 2006 and 2007 did not detect it outside New Jersey in the United States; all the other powdery Mildew-infected petunias, collected in New York and Indiana, were infected by Podosphaera xanthii. In Europe, most of the powdery Mildew-infected petunias examined in this study were infected by P. xanthii or Golovinomyces orontii. Our multiple inoculation tests revealed that the same petunia plants and even the same leaves can be infected concomitantly by O. longipes, O. neolycopersici, G. orontii, and P. xanthii. Thus, it is at present unclear to what extent O. longipes contributes to the powdery Mildew epidemics that develop year after year on solanaceous plants in many parts of the world.
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oidium neolycopersici intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species
Phytopathology, 2008Co-Authors: Tunde Jankovics, Yoshinori Matsuda, Hideyoshi Toyoda, Gabor M Kovacs, Rients E. Niks, Marc Bardin, Philippe Claude Nicot, Levente KissAbstract:Jankovics, T., Bai, Y., Kovacs, G. M., Bardin, M., Nicot, P. C., Toyoda, H., Matsuda, Y., Niks, R. E., and Kiss, L. 2008. Oidium neolycopersici: Intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species. Phytopathology 98:529-540. Previous works indicated a considerable variation in the pathogenicity, virulence, and host range of Oidium neolycopersici isolates causing tomato powdery Mildew epidemics in many parts of the world. In this study, rDNA internal transcribed spacer (ITS) sequences, and amplified fragment length polymorphism (AFLP) patterns were analyzed in 17 O. neolycopersici samples collected in Europe, North America, and Japan, including those which overcame some of the tomato major resistance genes. The ITS sequences were identical in all 10 samples tested and were also identical to ITS sequences of eight previously studied O. neolycopersici specimens. The AFLP analysis revealed a high genetic diversity in O. neolycopersici and indicated that all 17 samples represented different genotypes. This might suggest the existence of either a yet unrevealed sexual reproduction or other genetic mechanisms that maintain a high genetic variability in O. neolycopersici. No clear correlation was found between the virulence and the AFLP patterns of the O. neolycopersici isolates studied. The relationship between O. neolycopersici and powdery Mildew anamorphs infecting Aquilegia vulgaris, Chelidonium majus, Passiflora caerulea, and Sedum alboroseum was also investigated. These anamorphs are morphologically indistinguishable from and phylogenetically closely related to O. neolycopersici. The crossinoculation tests and the analyses of ITS sequences and AFLP patterns jointly indicated that the powdery Mildew anamorphs collected from the above mentioned plant species all represent distinct, but closely related species according to the phylogenetic species recognition. All these species were pathogenic only to their original host plant species, except O. neolycopersici which infected S. alboroseum, tobacco, petunia, and Arabidopsis thaliana, in addition to tomato, in cross-inoculation tests. This is the first genome-wide study that investigates the relationships among powdery Mildews that are closely related based on ITS sequences and morphology. The results indicate that morphologically indistinguishable powdery Mildews that differed in only one to five single nucleotide positions in their ITS region are to be considered as different taxa with distinct host ranges.
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oidium longipes a new powdery Mildew fungus on petunia in the usa a potential threat to ornamental and vegetable solanaceous crops
Plant Disease, 2008Co-Authors: Levente Kiss, Tunde Jankovics, Gabor M Kovacs, Margery L DaughtreyAbstract:ABSTRACT This is the first North American report of Oidium longipes, an anamorphic powdery Mildew species described recently in Europe. It was found on vegetatively propagated petunia grown in a commercial greenhouse in New Jersey, USA, where it caused a rapidly spreading disease. The pathogen might have originated offshore and may have already been distributed in the United States through horticultural trade. During field surveys in Europe, it was found on petunia in Hungary and Austria as well; this is the first report of O. longipes from these two countries. A detailed light microscopy study of American and European specimens of O. longipes, including freshly collected samples and authentic herbarium specimens, revealed that its conidiophore morphology is more variable than illustrated in the original species description or in subsequent works. Microcycle conidiation, a process not yet known to occur in powdery Mildews, was repeatedly observed in O. longipes. The rDNA internal transcribed spacer (ITS) ...
Gabor M Kovacs - One of the best experts on this subject based on the ideXlab platform.
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oidium longipes a new powdery Mildew fungus on petunia in the usa a potential threat to ornamental and vegetable solanaceous crops
Plant Disease, 2008Co-Authors: Levente Kiss, Tunde Jankovics, Gabor M Kovacs, Margery L DaughtreyAbstract:This is the first North American report of Oidium longipes, an anamorphic powdery Mildew species described recently in Europe. It was found on vegetatively propagated petunia grown in a commercial greenhouse in New Jersey, USA, where it caused a rapidly spreading disease. The pathogen might have originated offshore and may have already been distributed in the United States through horticultural trade. During field surveys in Europe, it was found on petunia in Hungary and Austria as well; this is the first report of O. longipes from these two countries. A detailed light microscopy study of American and European specimens of O. longipes, including freshly collected samples and authentic herbarium specimens, revealed that its conidiophore morphology is more variable than illustrated in the original species description or in subsequent works. Microcycle conidiation, a process not yet known to occur in powdery Mildews, was repeatedly observed in O. longipes. The rDNA internal transcribed spacer (ITS) sequences were identical in colonies containing different conidiophore types as well as in a total of five specimens collected from petunia in the United States, Austria, Hungary, Germany, and Switzerland. A phylogenetic analysis of the ITS sequences revealed that the closest known relative of O. longipes is O. lycopersici, known to infect tomato only in Australia. Cross-inoculation tests showed that O. longipes from petunia heavily infected tobacco cv. Xanthi, while the tomato and eggplant cultivars tested were moderately susceptible to this pathogen. These results indicate that its spread represents a potential danger to a number of solanaceous crops. Our ad hoc field surveys conducted in 2006 and 2007 did not detect it outside New Jersey in the United States; all the other powdery Mildew-infected petunias, collected in New York and Indiana, were infected by Podosphaera xanthii. In Europe, most of the powdery Mildew-infected petunias examined in this study were infected by P. xanthii or Golovinomyces orontii. Our multiple inoculation tests revealed that the same petunia plants and even the same leaves can be infected concomitantly by O. longipes, O. neolycopersici, G. orontii, and P. xanthii. Thus, it is at present unclear to what extent O. longipes contributes to the powdery Mildew epidemics that develop year after year on solanaceous plants in many parts of the world.
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oidium neolycopersici intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species
Phytopathology, 2008Co-Authors: Tunde Jankovics, Yoshinori Matsuda, Hideyoshi Toyoda, Gabor M Kovacs, Rients E. Niks, Marc Bardin, Philippe Claude Nicot, Levente KissAbstract:Jankovics, T., Bai, Y., Kovacs, G. M., Bardin, M., Nicot, P. C., Toyoda, H., Matsuda, Y., Niks, R. E., and Kiss, L. 2008. Oidium neolycopersici: Intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species. Phytopathology 98:529-540. Previous works indicated a considerable variation in the pathogenicity, virulence, and host range of Oidium neolycopersici isolates causing tomato powdery Mildew epidemics in many parts of the world. In this study, rDNA internal transcribed spacer (ITS) sequences, and amplified fragment length polymorphism (AFLP) patterns were analyzed in 17 O. neolycopersici samples collected in Europe, North America, and Japan, including those which overcame some of the tomato major resistance genes. The ITS sequences were identical in all 10 samples tested and were also identical to ITS sequences of eight previously studied O. neolycopersici specimens. The AFLP analysis revealed a high genetic diversity in O. neolycopersici and indicated that all 17 samples represented different genotypes. This might suggest the existence of either a yet unrevealed sexual reproduction or other genetic mechanisms that maintain a high genetic variability in O. neolycopersici. No clear correlation was found between the virulence and the AFLP patterns of the O. neolycopersici isolates studied. The relationship between O. neolycopersici and powdery Mildew anamorphs infecting Aquilegia vulgaris, Chelidonium majus, Passiflora caerulea, and Sedum alboroseum was also investigated. These anamorphs are morphologically indistinguishable from and phylogenetically closely related to O. neolycopersici. The crossinoculation tests and the analyses of ITS sequences and AFLP patterns jointly indicated that the powdery Mildew anamorphs collected from the above mentioned plant species all represent distinct, but closely related species according to the phylogenetic species recognition. All these species were pathogenic only to their original host plant species, except O. neolycopersici which infected S. alboroseum, tobacco, petunia, and Arabidopsis thaliana, in addition to tomato, in cross-inoculation tests. This is the first genome-wide study that investigates the relationships among powdery Mildews that are closely related based on ITS sequences and morphology. The results indicate that morphologically indistinguishable powdery Mildews that differed in only one to five single nucleotide positions in their ITS region are to be considered as different taxa with distinct host ranges.
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oidium longipes a new powdery Mildew fungus on petunia in the usa a potential threat to ornamental and vegetable solanaceous crops
Plant Disease, 2008Co-Authors: Levente Kiss, Tunde Jankovics, Gabor M Kovacs, Margery L DaughtreyAbstract:ABSTRACT This is the first North American report of Oidium longipes, an anamorphic powdery Mildew species described recently in Europe. It was found on vegetatively propagated petunia grown in a commercial greenhouse in New Jersey, USA, where it caused a rapidly spreading disease. The pathogen might have originated offshore and may have already been distributed in the United States through horticultural trade. During field surveys in Europe, it was found on petunia in Hungary and Austria as well; this is the first report of O. longipes from these two countries. A detailed light microscopy study of American and European specimens of O. longipes, including freshly collected samples and authentic herbarium specimens, revealed that its conidiophore morphology is more variable than illustrated in the original species description or in subsequent works. Microcycle conidiation, a process not yet known to occur in powdery Mildews, was repeatedly observed in O. longipes. The rDNA internal transcribed spacer (ITS) ...
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oidium neolycopersici intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species
Phytopathology, 2008Co-Authors: Tünde Jankovics, Yoshinori Matsuda, Hideyoshi Toyoda, Gabor M Kovacs, Rients E. Niks, Marc Bardin, Philippe Claude Nicot, Levente KissAbstract:Jankovics, T., Bai, Y., Kovacs, G. M., Bardin, M., Nicot, P. C., Toyoda, H., Matsuda, Y., Niks, R. E., and Kiss, L. 2008. Oidium neolycopersici: Intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species. Phytopathology 98:529-540. Previous works indicated a considerable variation in the pathogenicity, virulence, and host range of Oidium neolycopersici isolates causing tomato powdery Mildew epidemics in many parts of the world. In this study, rDNA internal transcribed spacer (ITS) sequences, and amplified fragment length polymorphism (AFLP) patterns were analyzed in 17 O. neolycopersici samples collected in Europe, North America, and Japan, including those which overcame some of the tomato major resistance genes. The ITS sequences were identical in all 10 samples tested and were also identical to ITS sequences of eight previously studied O. neolycopersici specimens. The AFLP analysis revealed a high genetic diversity in O. neolycopersici and indicated that all 17 samples represented different genotypes. This might suggest the existence of either a yet unrevealed sexual reproduction or other genetic mechanisms that maintain a high genetic variability in O. neolycopersici. No clear correlation was found between the virulence and the AFLP patterns of the O. neolycopersici isolates studied. The relationship between O. neolycopersici and powdery Mildew anamorphs infecting Aquilegia vulgaris, Chelidonium majus, Passiflora caerulea, and Sedum alboroseum was also investigated. These anamorphs are morphologically indistinguishable from and phylogenetically closely related to O. neolycopersici. The crossinoculation tests and the analyses of ITS sequences and AFLP patterns jointly indicated that the powdery Mildew anamorphs collected from the above mentioned plant species all represent distinct, but closely related species according to the phylogenetic species recognition. All these species were pathogenic only to their original host plant species, except O. neolycopersici which infected S. alboroseum, tobacco, petunia, and Arabidopsis thaliana, in addition to tomato, in cross-inoculation tests. This is the first genome-wide study that investigates the relationships among powdery Mildews that are closely related based on ITS sequences and morphology. The results indicate that morphologically indistinguishable powdery Mildews that differed in only one to five single nucleotide positions in their ITS region are to be considered as different taxa with distinct host ranges.
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oidium longipes a new powdery Mildew fungus on petunia in the usa a potential threat to ornamental and vegetable solanaceous crops
Plant Disease, 2008Co-Authors: Levente Kiss, Tunde Jankovics, Gabor M Kovacs, Margery L DaughtreyAbstract:ABSTRACT This is the first North American report of Oidium longipes, an anamorphic powdery Mildew species described recently in Europe. It was found on vegetatively propagated petunia grown in a commercial greenhouse in New Jersey, USA, where it caused a rapidly spreading disease. The pathogen might have originated offshore and may have already been distributed in the United States through horticultural trade. During field surveys in Europe, it was found on petunia in Hungary and Austria as well; this is the first report of O. longipes from these two countries. A detailed light microscopy study of American and European specimens of O. longipes, including freshly collected samples and authentic herbarium specimens, revealed that its conidiophore morphology is more variable than illustrated in the original species description or in subsequent works. Microcycle conidiation, a process not yet known to occur in powdery Mildews, was repeatedly observed in O. longipes. The rDNA internal transcribed spacer (ITS) ...
Tunde Jankovics - One of the best experts on this subject based on the ideXlab platform.
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oidium longipes a new powdery Mildew fungus on petunia in the usa a potential threat to ornamental and vegetable solanaceous crops
Plant Disease, 2008Co-Authors: Levente Kiss, Tunde Jankovics, Gabor M Kovacs, Margery L DaughtreyAbstract:This is the first North American report of Oidium longipes, an anamorphic powdery Mildew species described recently in Europe. It was found on vegetatively propagated petunia grown in a commercial greenhouse in New Jersey, USA, where it caused a rapidly spreading disease. The pathogen might have originated offshore and may have already been distributed in the United States through horticultural trade. During field surveys in Europe, it was found on petunia in Hungary and Austria as well; this is the first report of O. longipes from these two countries. A detailed light microscopy study of American and European specimens of O. longipes, including freshly collected samples and authentic herbarium specimens, revealed that its conidiophore morphology is more variable than illustrated in the original species description or in subsequent works. Microcycle conidiation, a process not yet known to occur in powdery Mildews, was repeatedly observed in O. longipes. The rDNA internal transcribed spacer (ITS) sequences were identical in colonies containing different conidiophore types as well as in a total of five specimens collected from petunia in the United States, Austria, Hungary, Germany, and Switzerland. A phylogenetic analysis of the ITS sequences revealed that the closest known relative of O. longipes is O. lycopersici, known to infect tomato only in Australia. Cross-inoculation tests showed that O. longipes from petunia heavily infected tobacco cv. Xanthi, while the tomato and eggplant cultivars tested were moderately susceptible to this pathogen. These results indicate that its spread represents a potential danger to a number of solanaceous crops. Our ad hoc field surveys conducted in 2006 and 2007 did not detect it outside New Jersey in the United States; all the other powdery Mildew-infected petunias, collected in New York and Indiana, were infected by Podosphaera xanthii. In Europe, most of the powdery Mildew-infected petunias examined in this study were infected by P. xanthii or Golovinomyces orontii. Our multiple inoculation tests revealed that the same petunia plants and even the same leaves can be infected concomitantly by O. longipes, O. neolycopersici, G. orontii, and P. xanthii. Thus, it is at present unclear to what extent O. longipes contributes to the powdery Mildew epidemics that develop year after year on solanaceous plants in many parts of the world.
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oidium neolycopersici intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species
Phytopathology, 2008Co-Authors: Tunde Jankovics, Yoshinori Matsuda, Hideyoshi Toyoda, Gabor M Kovacs, Rients E. Niks, Marc Bardin, Philippe Claude Nicot, Levente KissAbstract:Jankovics, T., Bai, Y., Kovacs, G. M., Bardin, M., Nicot, P. C., Toyoda, H., Matsuda, Y., Niks, R. E., and Kiss, L. 2008. Oidium neolycopersici: Intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species. Phytopathology 98:529-540. Previous works indicated a considerable variation in the pathogenicity, virulence, and host range of Oidium neolycopersici isolates causing tomato powdery Mildew epidemics in many parts of the world. In this study, rDNA internal transcribed spacer (ITS) sequences, and amplified fragment length polymorphism (AFLP) patterns were analyzed in 17 O. neolycopersici samples collected in Europe, North America, and Japan, including those which overcame some of the tomato major resistance genes. The ITS sequences were identical in all 10 samples tested and were also identical to ITS sequences of eight previously studied O. neolycopersici specimens. The AFLP analysis revealed a high genetic diversity in O. neolycopersici and indicated that all 17 samples represented different genotypes. This might suggest the existence of either a yet unrevealed sexual reproduction or other genetic mechanisms that maintain a high genetic variability in O. neolycopersici. No clear correlation was found between the virulence and the AFLP patterns of the O. neolycopersici isolates studied. The relationship between O. neolycopersici and powdery Mildew anamorphs infecting Aquilegia vulgaris, Chelidonium majus, Passiflora caerulea, and Sedum alboroseum was also investigated. These anamorphs are morphologically indistinguishable from and phylogenetically closely related to O. neolycopersici. The crossinoculation tests and the analyses of ITS sequences and AFLP patterns jointly indicated that the powdery Mildew anamorphs collected from the above mentioned plant species all represent distinct, but closely related species according to the phylogenetic species recognition. All these species were pathogenic only to their original host plant species, except O. neolycopersici which infected S. alboroseum, tobacco, petunia, and Arabidopsis thaliana, in addition to tomato, in cross-inoculation tests. This is the first genome-wide study that investigates the relationships among powdery Mildews that are closely related based on ITS sequences and morphology. The results indicate that morphologically indistinguishable powdery Mildews that differed in only one to five single nucleotide positions in their ITS region are to be considered as different taxa with distinct host ranges.
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oidium longipes a new powdery Mildew fungus on petunia in the usa a potential threat to ornamental and vegetable solanaceous crops
Plant Disease, 2008Co-Authors: Levente Kiss, Tunde Jankovics, Gabor M Kovacs, Margery L DaughtreyAbstract:ABSTRACT This is the first North American report of Oidium longipes, an anamorphic powdery Mildew species described recently in Europe. It was found on vegetatively propagated petunia grown in a commercial greenhouse in New Jersey, USA, where it caused a rapidly spreading disease. The pathogen might have originated offshore and may have already been distributed in the United States through horticultural trade. During field surveys in Europe, it was found on petunia in Hungary and Austria as well; this is the first report of O. longipes from these two countries. A detailed light microscopy study of American and European specimens of O. longipes, including freshly collected samples and authentic herbarium specimens, revealed that its conidiophore morphology is more variable than illustrated in the original species description or in subsequent works. Microcycle conidiation, a process not yet known to occur in powdery Mildews, was repeatedly observed in O. longipes. The rDNA internal transcribed spacer (ITS) ...
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oidium longipes a new powdery Mildew fungus on petunia in the usa a potential threat to ornamental and vegetable solanaceous crops
Plant Disease, 2008Co-Authors: Levente Kiss, Tunde Jankovics, Gabor M Kovacs, Margery L DaughtreyAbstract:ABSTRACT This is the first North American report of Oidium longipes, an anamorphic powdery Mildew species described recently in Europe. It was found on vegetatively propagated petunia grown in a commercial greenhouse in New Jersey, USA, where it caused a rapidly spreading disease. The pathogen might have originated offshore and may have already been distributed in the United States through horticultural trade. During field surveys in Europe, it was found on petunia in Hungary and Austria as well; this is the first report of O. longipes from these two countries. A detailed light microscopy study of American and European specimens of O. longipes, including freshly collected samples and authentic herbarium specimens, revealed that its conidiophore morphology is more variable than illustrated in the original species description or in subsequent works. Microcycle conidiation, a process not yet known to occur in powdery Mildews, was repeatedly observed in O. longipes. The rDNA internal transcribed spacer (ITS) ...
Hideyoshi Toyoda - One of the best experts on this subject based on the ideXlab platform.
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loss of function in mlo orthologs reduces susceptibility of pepper and tomato to powdery Mildew disease caused by leveillula taurica
PLOS ONE, 2013Co-Authors: Zheng Zheng, Yoshinori Matsuda, Hideyoshi Toyoda, Teruo Nonomura, Michela Appiano, Stefano Pavan, Annemarie A Wolters, Richard G F Visser, Yuling BaiAbstract:Powdery Mildew disease caused by Leveillula taurica is a serious fungal threat to greenhouse tomato and pepper production. In contrast to most powdery Mildew species which are epiphytic, L. taurica is an endophytic fungus colonizing the mesophyll tissues of the leaf. In barley, Arabidopsis, tomato and pea, the correct functioning of specific homologues of the plant Mlo gene family has been found to be required for pathogenesis of epiphytic powdery Mildew fungi. The aim of this study was to investigate the involvement of the Mlo genes in susceptibility to the endophytic fungus L. taurica. In tomato (Solanum lycopersicum), a loss-of-function mutation in the SlMlo1 gene results in resistance to powdery Mildew disease caused by Oidium neolycopersici. When the tomato Slmlo1 mutant was inoculated with L. taurica in this study, it proved to be less susceptible compared to the control, S. lycopersicum cv. Moneymaker. Further, overexpression of SlMlo1 in the tomato Slmlo1 mutant enhanced susceptibility to L. taurica. In pepper, the CaMlo2 gene was isolated by applying a homology-based cloning approach. Compared to the previously identified CaMlo1 gene, the CaMlo2 gene is more similar to SlMlo1 as shown by phylogenetic analysis, and the expression of CaMlo2 is up-regulated at an earlier time point upon L. taurica infection. However, results of virus-induced gene silencing suggest that both CaMlo1 and CaMlo2 may be involved in the susceptibility of pepper to L. taurica. The fact that overexpression of CaMlo2 restored the susceptibility of the tomato Slmlo1 mutant to O. neolycopersici and increased its susceptibility to L. taurica confirmed the role of CaMlo2 acting as a susceptibility factor to different powdery Mildews, though the role of CaMlo1 as a co-factor for susceptibility cannot be excluded.
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oidium neolycopersici intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species
Phytopathology, 2008Co-Authors: Tunde Jankovics, Yoshinori Matsuda, Hideyoshi Toyoda, Gabor M Kovacs, Rients E. Niks, Marc Bardin, Philippe Claude Nicot, Levente KissAbstract:Jankovics, T., Bai, Y., Kovacs, G. M., Bardin, M., Nicot, P. C., Toyoda, H., Matsuda, Y., Niks, R. E., and Kiss, L. 2008. Oidium neolycopersici: Intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species. Phytopathology 98:529-540. Previous works indicated a considerable variation in the pathogenicity, virulence, and host range of Oidium neolycopersici isolates causing tomato powdery Mildew epidemics in many parts of the world. In this study, rDNA internal transcribed spacer (ITS) sequences, and amplified fragment length polymorphism (AFLP) patterns were analyzed in 17 O. neolycopersici samples collected in Europe, North America, and Japan, including those which overcame some of the tomato major resistance genes. The ITS sequences were identical in all 10 samples tested and were also identical to ITS sequences of eight previously studied O. neolycopersici specimens. The AFLP analysis revealed a high genetic diversity in O. neolycopersici and indicated that all 17 samples represented different genotypes. This might suggest the existence of either a yet unrevealed sexual reproduction or other genetic mechanisms that maintain a high genetic variability in O. neolycopersici. No clear correlation was found between the virulence and the AFLP patterns of the O. neolycopersici isolates studied. The relationship between O. neolycopersici and powdery Mildew anamorphs infecting Aquilegia vulgaris, Chelidonium majus, Passiflora caerulea, and Sedum alboroseum was also investigated. These anamorphs are morphologically indistinguishable from and phylogenetically closely related to O. neolycopersici. The crossinoculation tests and the analyses of ITS sequences and AFLP patterns jointly indicated that the powdery Mildew anamorphs collected from the above mentioned plant species all represent distinct, but closely related species according to the phylogenetic species recognition. All these species were pathogenic only to their original host plant species, except O. neolycopersici which infected S. alboroseum, tobacco, petunia, and Arabidopsis thaliana, in addition to tomato, in cross-inoculation tests. This is the first genome-wide study that investigates the relationships among powdery Mildews that are closely related based on ITS sequences and morphology. The results indicate that morphologically indistinguishable powdery Mildews that differed in only one to five single nucleotide positions in their ITS region are to be considered as different taxa with distinct host ranges.
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oidium neolycopersici intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species
Phytopathology, 2008Co-Authors: Tünde Jankovics, Yoshinori Matsuda, Hideyoshi Toyoda, Gabor M Kovacs, Rients E. Niks, Marc Bardin, Philippe Claude Nicot, Levente KissAbstract:Jankovics, T., Bai, Y., Kovacs, G. M., Bardin, M., Nicot, P. C., Toyoda, H., Matsuda, Y., Niks, R. E., and Kiss, L. 2008. Oidium neolycopersici: Intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species. Phytopathology 98:529-540. Previous works indicated a considerable variation in the pathogenicity, virulence, and host range of Oidium neolycopersici isolates causing tomato powdery Mildew epidemics in many parts of the world. In this study, rDNA internal transcribed spacer (ITS) sequences, and amplified fragment length polymorphism (AFLP) patterns were analyzed in 17 O. neolycopersici samples collected in Europe, North America, and Japan, including those which overcame some of the tomato major resistance genes. The ITS sequences were identical in all 10 samples tested and were also identical to ITS sequences of eight previously studied O. neolycopersici specimens. The AFLP analysis revealed a high genetic diversity in O. neolycopersici and indicated that all 17 samples represented different genotypes. This might suggest the existence of either a yet unrevealed sexual reproduction or other genetic mechanisms that maintain a high genetic variability in O. neolycopersici. No clear correlation was found between the virulence and the AFLP patterns of the O. neolycopersici isolates studied. The relationship between O. neolycopersici and powdery Mildew anamorphs infecting Aquilegia vulgaris, Chelidonium majus, Passiflora caerulea, and Sedum alboroseum was also investigated. These anamorphs are morphologically indistinguishable from and phylogenetically closely related to O. neolycopersici. The crossinoculation tests and the analyses of ITS sequences and AFLP patterns jointly indicated that the powdery Mildew anamorphs collected from the above mentioned plant species all represent distinct, but closely related species according to the phylogenetic species recognition. All these species were pathogenic only to their original host plant species, except O. neolycopersici which infected S. alboroseum, tobacco, petunia, and Arabidopsis thaliana, in addition to tomato, in cross-inoculation tests. This is the first genome-wide study that investigates the relationships among powdery Mildews that are closely related based on ITS sequences and morphology. The results indicate that morphologically indistinguishable powdery Mildews that differed in only one to five single nucleotide positions in their ITS region are to be considered as different taxa with distinct host ranges.
Yoshinori Matsuda - One of the best experts on this subject based on the ideXlab platform.
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loss of function in mlo orthologs reduces susceptibility of pepper and tomato to powdery Mildew disease caused by leveillula taurica
PLOS ONE, 2013Co-Authors: Zheng Zheng, Yoshinori Matsuda, Hideyoshi Toyoda, Teruo Nonomura, Michela Appiano, Stefano Pavan, Annemarie A Wolters, Richard G F Visser, Yuling BaiAbstract:Powdery Mildew disease caused by Leveillula taurica is a serious fungal threat to greenhouse tomato and pepper production. In contrast to most powdery Mildew species which are epiphytic, L. taurica is an endophytic fungus colonizing the mesophyll tissues of the leaf. In barley, Arabidopsis, tomato and pea, the correct functioning of specific homologues of the plant Mlo gene family has been found to be required for pathogenesis of epiphytic powdery Mildew fungi. The aim of this study was to investigate the involvement of the Mlo genes in susceptibility to the endophytic fungus L. taurica. In tomato (Solanum lycopersicum), a loss-of-function mutation in the SlMlo1 gene results in resistance to powdery Mildew disease caused by Oidium neolycopersici. When the tomato Slmlo1 mutant was inoculated with L. taurica in this study, it proved to be less susceptible compared to the control, S. lycopersicum cv. Moneymaker. Further, overexpression of SlMlo1 in the tomato Slmlo1 mutant enhanced susceptibility to L. taurica. In pepper, the CaMlo2 gene was isolated by applying a homology-based cloning approach. Compared to the previously identified CaMlo1 gene, the CaMlo2 gene is more similar to SlMlo1 as shown by phylogenetic analysis, and the expression of CaMlo2 is up-regulated at an earlier time point upon L. taurica infection. However, results of virus-induced gene silencing suggest that both CaMlo1 and CaMlo2 may be involved in the susceptibility of pepper to L. taurica. The fact that overexpression of CaMlo2 restored the susceptibility of the tomato Slmlo1 mutant to O. neolycopersici and increased its susceptibility to L. taurica confirmed the role of CaMlo2 acting as a susceptibility factor to different powdery Mildews, though the role of CaMlo1 as a co-factor for susceptibility cannot be excluded.
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oidium neolycopersici intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species
Phytopathology, 2008Co-Authors: Tunde Jankovics, Yoshinori Matsuda, Hideyoshi Toyoda, Gabor M Kovacs, Rients E. Niks, Marc Bardin, Philippe Claude Nicot, Levente KissAbstract:Jankovics, T., Bai, Y., Kovacs, G. M., Bardin, M., Nicot, P. C., Toyoda, H., Matsuda, Y., Niks, R. E., and Kiss, L. 2008. Oidium neolycopersici: Intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species. Phytopathology 98:529-540. Previous works indicated a considerable variation in the pathogenicity, virulence, and host range of Oidium neolycopersici isolates causing tomato powdery Mildew epidemics in many parts of the world. In this study, rDNA internal transcribed spacer (ITS) sequences, and amplified fragment length polymorphism (AFLP) patterns were analyzed in 17 O. neolycopersici samples collected in Europe, North America, and Japan, including those which overcame some of the tomato major resistance genes. The ITS sequences were identical in all 10 samples tested and were also identical to ITS sequences of eight previously studied O. neolycopersici specimens. The AFLP analysis revealed a high genetic diversity in O. neolycopersici and indicated that all 17 samples represented different genotypes. This might suggest the existence of either a yet unrevealed sexual reproduction or other genetic mechanisms that maintain a high genetic variability in O. neolycopersici. No clear correlation was found between the virulence and the AFLP patterns of the O. neolycopersici isolates studied. The relationship between O. neolycopersici and powdery Mildew anamorphs infecting Aquilegia vulgaris, Chelidonium majus, Passiflora caerulea, and Sedum alboroseum was also investigated. These anamorphs are morphologically indistinguishable from and phylogenetically closely related to O. neolycopersici. The crossinoculation tests and the analyses of ITS sequences and AFLP patterns jointly indicated that the powdery Mildew anamorphs collected from the above mentioned plant species all represent distinct, but closely related species according to the phylogenetic species recognition. All these species were pathogenic only to their original host plant species, except O. neolycopersici which infected S. alboroseum, tobacco, petunia, and Arabidopsis thaliana, in addition to tomato, in cross-inoculation tests. This is the first genome-wide study that investigates the relationships among powdery Mildews that are closely related based on ITS sequences and morphology. The results indicate that morphologically indistinguishable powdery Mildews that differed in only one to five single nucleotide positions in their ITS region are to be considered as different taxa with distinct host ranges.
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oidium neolycopersici intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species
Phytopathology, 2008Co-Authors: Tünde Jankovics, Yoshinori Matsuda, Hideyoshi Toyoda, Gabor M Kovacs, Rients E. Niks, Marc Bardin, Philippe Claude Nicot, Levente KissAbstract:Jankovics, T., Bai, Y., Kovacs, G. M., Bardin, M., Nicot, P. C., Toyoda, H., Matsuda, Y., Niks, R. E., and Kiss, L. 2008. Oidium neolycopersici: Intraspecific variability inferred from amplified fragment length polymorphism analysis and relationship with closely related powdery Mildew fungi infecting various plant species. Phytopathology 98:529-540. Previous works indicated a considerable variation in the pathogenicity, virulence, and host range of Oidium neolycopersici isolates causing tomato powdery Mildew epidemics in many parts of the world. In this study, rDNA internal transcribed spacer (ITS) sequences, and amplified fragment length polymorphism (AFLP) patterns were analyzed in 17 O. neolycopersici samples collected in Europe, North America, and Japan, including those which overcame some of the tomato major resistance genes. The ITS sequences were identical in all 10 samples tested and were also identical to ITS sequences of eight previously studied O. neolycopersici specimens. The AFLP analysis revealed a high genetic diversity in O. neolycopersici and indicated that all 17 samples represented different genotypes. This might suggest the existence of either a yet unrevealed sexual reproduction or other genetic mechanisms that maintain a high genetic variability in O. neolycopersici. No clear correlation was found between the virulence and the AFLP patterns of the O. neolycopersici isolates studied. The relationship between O. neolycopersici and powdery Mildew anamorphs infecting Aquilegia vulgaris, Chelidonium majus, Passiflora caerulea, and Sedum alboroseum was also investigated. These anamorphs are morphologically indistinguishable from and phylogenetically closely related to O. neolycopersici. The crossinoculation tests and the analyses of ITS sequences and AFLP patterns jointly indicated that the powdery Mildew anamorphs collected from the above mentioned plant species all represent distinct, but closely related species according to the phylogenetic species recognition. All these species were pathogenic only to their original host plant species, except O. neolycopersici which infected S. alboroseum, tobacco, petunia, and Arabidopsis thaliana, in addition to tomato, in cross-inoculation tests. This is the first genome-wide study that investigates the relationships among powdery Mildews that are closely related based on ITS sequences and morphology. The results indicate that morphologically indistinguishable powdery Mildews that differed in only one to five single nucleotide positions in their ITS region are to be considered as different taxa with distinct host ranges.
