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Hanafy M Fouly - One of the best experts on this subject based on the ideXlab platform.
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transformation of Gaeumannomyces graminis with β glucuronidase reporter and hygromycin resistance genes
Journal of Phytopathology, 2011Co-Authors: Joel Park, Henry T Wilkinson, Osman Radwan, Bruce Martin, Hanafy M FoulyAbstract:Take-all disease is caused by Gaeumannomyces graminis, (Sacc.) Arx & D. Olivier, a soil-borne fungus, which colonizes the root and crown tissue of many members of the Poaceae plant family. This fungus is able to grow along the surface of roots as darkly pigmented runner hyphae, which has the ability to penetrate the root. Here, we describe a genetic transformation of G. graminis var. graminis by using polyethylene glycol (PEG)-based protoplast transformation. Fungus cells were transformed with a plasmid, pHPG, containing the gusA reporter gene that codes for β-glucuronidase (GUS) and the hph gene for hygromycin resistance as the selectable marker. A de novo transformant selection assay was developed to identify the putative transformants that were expressing the hph gene. In addition, the transformed cells maintained the ability to infect the plant tissues. The GUS-expressing fungus can be used to study fungal infection processes including fungal penetration, colonization and the role(s) of melanin during pathogenesis. Thus, this study is the first report of G. graminis var. graminis transformed with a visibly detectable reporter gene that provides a useful tool to a better understanding of host-Gaeumannomyces interactions.
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detection of Gaeumannomyces graminis varieties using polymerase chain reaction with variety specific primers
Plant Disease, 2000Co-Authors: Hanafy M Fouly, H T WilkinsonAbstract:The polymerase chain reaction (PCR) was used for detection of Gaeumannomyces graminis, the causal agent of take-all disease in wheat, oats, and turfgrass. NS5 and NS6 universal primers amplified the middle region of 18S ribosomal DNA of Gaeumannomyces species and varieties. Primers GGT-RP (5' TGCAATGGCTTCGTGAA 3') and GGA-RP (5' TTTGTGTGTGAC CATAC 3') were developed by sequence analysis of cloned NS5-NS6 fragments. The primer pair NS5:GGT-RP amplified a single 410-bp fragment from isolates of G. graminis var. tritici, a single 300-bp fragment from isolates of G. graminis var. avenae, and no amplification products from isolates of G. graminis var. graminis or other species of Gaeumannomyces. The primer pair NS5:GGA-RP amplified a single 400-bp fragment from isolates of varieties tritici and avenae. Two sets of primer pairs (NS5:GGT-RP and NS5:GGA-RP) were used in PCR reactions to detect and identify the varieties tritici and avenae either colonizing wheat, oats, or grass roots, or in culture. No amplification products were observed using DNA extracted from plants infected with eight other soilborne fungal pathogens or from uninoculated plants.
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a group i intron in the nuclear small subunit ribosomal dna of Gaeumannomyces graminis
Current Microbiology, 2000Co-Authors: Hanafy M Fouly, Henry T WilkinsonAbstract:The length of the small subunit ribosomal DNA (SSU rDNA) differs among isolates of species and varieties of Gaeumannomyces. The sequence of the 3′ region of the SSU rDNA revealed 340-, 365-, and 520-bp insertions for G. graminis varieties avenae, tritici, and graminis, respectively. The intron sequences from varities tritici and avenae were similar, except there was an insert of 23 nucleotides at base 328 from the 5′ end of the G. g. var. tritici intron. The G. g. var. graminis intron sequences had 92.4% homology compared with the intron sequences of varieties tritici and avenae. In addition, the intron sequence of variety graminis is larger, having an insert of 155 nucleotides at base 365 of the 5′ end of the intron. Little variation in the DNA sequences flanking the introns has been detected among the isolates of Gaeumannomyces that either have or lack an intron. Reverse transcriptase PCR (RT-PCR) indicated the absence of the intron in the mature rRNA. The intron sequence had both a conserved sequence and secondary structural elements classifying it as a group I intron.
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restriction analysis of internal transcribed spacers and the small subunit gene of ribosomal dna among four Gaeumannomyces species
Mycologia, 1997Co-Authors: Hanafy M Fouly, Henry T Wilkinson, Weidong ChenAbstract:The 18S rDNA and the region spanning the two internal transcribed spacers (ITS), which in- cludes the 5.8S rDNA, from 36 isolates of four species of Gaeumannomyces (G. graminis, G. incrustans, G. cylindrosporous, and G. leptosporous) were amplified using the polymerase chain reaction. The amplified products were subjected to restriction enzyme diges- tion. The restriction patterns in the ITS regions sep- arated both the species of Gaeumannomyces and the three varieties of G. graminis. Specific variation in restriction patterns of the ITS regions was observed within the isolates of G. g. var. graminis. Physical maps of the restriction sites in the ITS region were constructed. Variation among isolates of G. g. var. tri- tici and G. g. var. avenae was minimal. The 3' end and 5' end of the 18S rDNA are conserved among
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use of random amplified polymorphic dna rapd for identification of Gaeumannomyces species
Soil Biology & Biochemistry, 1996Co-Authors: Hanafy M Fouly, Henry T Wilkinson, Leslie L DomierAbstract:Abstract Randomly amplified polymorphic DNAs (RAPD) were used to distinguish among isolates of Gaeumannomyces graminis var. tritici, G. g. var. graminis, G. g. var. avenae, G. incrustans, and G. cylindrosporous. Of 60 random sequence decamer primers tested, 28 produced bands and 15 showed evidence of polymorphism. Four primers produced DNA amplification patterns that were used to distinguish G. graminis, G. incrustans, and G. cylindrosporous. Banding patterns were similar within isolates of G. g. var. tritici, G. g. var. avenae and G. incrustans. G. g. var. graminis showed greater variability in banding patterns. The unweighted pair group method with arithmetical averages (UPGMA) indicated that G. g. var. tritici isolates were more closely related to G. g. var. avenae than to G. g. var. graminis isolates. The results of our study showed that RAPD markers can be used to confirm the identification of Gaeumannomyces species and varieties.
Joan M Henson - One of the best experts on this subject based on the ideXlab platform.
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Effect of osmotic stress on growth of Gaeumannomyces graminis strains differing in hyphal pigmentation
Mycologia, 2020Co-Authors: Monica L. Elliott, Joan M HensonAbstract:The effect of osmotic stress on mycelial growth was determined for melanized and nonmela- nized strains of Gaeumannomyces graminis var. tritici and var. graminis using a minimal salts medium, both in liquid and solid form. The osmotica used were KCl and sucrose. Growth measurements obtained from
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Heavily-melanized variants of the sexual Gaeumannomyces graminis var. tritici are non-pathogenic and indistinguishable from the asexual, Phialophora state
Fungal Biology, 2002Co-Authors: Tresa Q. Coins, William A. Edens, Joan M HensonAbstract:Gaeumannomyces graminis var. tritici is the aetiologic agent of take-all disease of wheat and barley. Heavily-melanized variants of a lightly pigmented, virulent wild-type strain were isolated and characterized. These variants were phenotypically similar to Phialophora sp., the proposed anamorph of Gaeumannomyces graminis var. tritici. Unlike the wild-type G. graminis strain, Phialophora-like variants produced conidia and lost their ability to reproduce sexually after serial transfer. Some ascospores from initial self-crosses of the Phialophora-like variants regained the G. graminis phenotype, and these derivatives could again produce Phialophora-like variants. As with Phialophora isolates from the field, Phialophora-like variants produced in this study were non-pathogenic and produced less extracellular protein.
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Mitochondrial Plasmids of the Gaeumannomyces-Phialophora Complex and Their Detection by Primed, in Situ Fluorescence Labeling
Experimental Mycology, 1995Co-Authors: Joan M HensonAbstract:Abstract Henson, J. M., and Caesar-TonThat, T. C. 1995. Mitochondrial plasmids of the Gaeumannomyces-Phialophora complex and their detection by primed, in situ fluorescence labeling. Experimental Mycology 19, 263-274. Double-stranded, linear DNA mitochondrial plasmids were detected in most Gaeumannomyces graminis var. tritici and var. avenae isolates, but were infrequently detected in G. graminis var. graminis , and only detected once in other Gaeumannomyces or Magnaporthe species. Plasmids were 4-11 kb and were apparently blocked at their 5′ termini, as they were resistant to 5′ → 3′ exonuclease digestion. Two plasmids that shared homology were further characterized. Apparently they were not derived from the mitochondrial or nuclear genomes as they did not hybridize strongly to them. An internal fragment was cloned from one plasmid and used as a primer for primed, in situ labeling with cryosectioned hyphae. Plasmid-bearing strains had fluorescent signal in a pattern expected of a mitochondrial location for plasmids, whereas plasmid-less strains did not fluoresce. This is the first use of cryosectioned hyphae and mitochondrial probes with in situ fluorescence labeling in fungi.
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The fate of integrated DNA in Gaeumannomyces graminis transformants
Fems Microbiology Letters, 1993Co-Authors: Alice L Pilgeram, Tresa Goins, Joan M HensonAbstract:The fate of integrated transforming DNA in fungicide (benomyl or phleomycin)-resistant transformants of Gaeumannomyces graminis was investigated. Transforming DNA was mitotically and meiotically stable in several transformants. However, other transformants of varieties graminis and tritici were less resistant to fungicide after meiosis. Hybridization analyses indicated that transforming DNA in ascospore progeny had rearrangements and/or deletions, and that similar events could occur during a second meiotic cycle, further reducing their levels of resistance. Rearrangements and/or deletions were most common in transformants with multiple copies of a benomyl-resistance (Benr) plasmid. Transforming sequences were not extensively methylated, even when present in multiple copies.
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use of polymerase chain reaction to detect Gaeumannomyces graminis dna in plants grown in artificially and naturally infested soil
Phytopathology, 1993Co-Authors: Joan M Henson, T Goins, W Grey, D E Mathre, M L ElliottAbstract:The polymerase chain reaction was used to specifically amplify DNA of Gaeumannomyces graminis, a filamentous soilborne fungus that causes root and crown disease of cereals and turfgrasses. Nested primers were used to amplify a 188-bp fragment of mitochondrial DNA from fungal and infected-plant samples, which were simply boiled to release target DNA. Fungal DNA was amplified from single boiled hyphal tips or ascospores. G. graminis DNA was also detected in boiled crowns and roots from experimentally and naturally infected wheat, rice, and St. Augustine-grass and experimentally infected bermudagrass []
Henry T Wilkinson - One of the best experts on this subject based on the ideXlab platform.
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transformation of Gaeumannomyces graminis with β glucuronidase reporter and hygromycin resistance genes
Journal of Phytopathology, 2011Co-Authors: Joel Park, Henry T Wilkinson, Osman Radwan, Bruce Martin, Hanafy M FoulyAbstract:Take-all disease is caused by Gaeumannomyces graminis, (Sacc.) Arx & D. Olivier, a soil-borne fungus, which colonizes the root and crown tissue of many members of the Poaceae plant family. This fungus is able to grow along the surface of roots as darkly pigmented runner hyphae, which has the ability to penetrate the root. Here, we describe a genetic transformation of G. graminis var. graminis by using polyethylene glycol (PEG)-based protoplast transformation. Fungus cells were transformed with a plasmid, pHPG, containing the gusA reporter gene that codes for β-glucuronidase (GUS) and the hph gene for hygromycin resistance as the selectable marker. A de novo transformant selection assay was developed to identify the putative transformants that were expressing the hph gene. In addition, the transformed cells maintained the ability to infect the plant tissues. The GUS-expressing fungus can be used to study fungal infection processes including fungal penetration, colonization and the role(s) of melanin during pathogenesis. Thus, this study is the first report of G. graminis var. graminis transformed with a visibly detectable reporter gene that provides a useful tool to a better understanding of host-Gaeumannomyces interactions.
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a group i intron in the nuclear small subunit ribosomal dna of Gaeumannomyces graminis
Current Microbiology, 2000Co-Authors: Hanafy M Fouly, Henry T WilkinsonAbstract:The length of the small subunit ribosomal DNA (SSU rDNA) differs among isolates of species and varieties of Gaeumannomyces. The sequence of the 3′ region of the SSU rDNA revealed 340-, 365-, and 520-bp insertions for G. graminis varieties avenae, tritici, and graminis, respectively. The intron sequences from varities tritici and avenae were similar, except there was an insert of 23 nucleotides at base 328 from the 5′ end of the G. g. var. tritici intron. The G. g. var. graminis intron sequences had 92.4% homology compared with the intron sequences of varieties tritici and avenae. In addition, the intron sequence of variety graminis is larger, having an insert of 155 nucleotides at base 365 of the 5′ end of the intron. Little variation in the DNA sequences flanking the introns has been detected among the isolates of Gaeumannomyces that either have or lack an intron. Reverse transcriptase PCR (RT-PCR) indicated the absence of the intron in the mature rRNA. The intron sequence had both a conserved sequence and secondary structural elements classifying it as a group I intron.
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restriction analysis of internal transcribed spacers and the small subunit gene of ribosomal dna among four Gaeumannomyces species
Mycologia, 1997Co-Authors: Hanafy M Fouly, Henry T Wilkinson, Weidong ChenAbstract:The 18S rDNA and the region spanning the two internal transcribed spacers (ITS), which in- cludes the 5.8S rDNA, from 36 isolates of four species of Gaeumannomyces (G. graminis, G. incrustans, G. cylindrosporous, and G. leptosporous) were amplified using the polymerase chain reaction. The amplified products were subjected to restriction enzyme diges- tion. The restriction patterns in the ITS regions sep- arated both the species of Gaeumannomyces and the three varieties of G. graminis. Specific variation in restriction patterns of the ITS regions was observed within the isolates of G. g. var. graminis. Physical maps of the restriction sites in the ITS region were constructed. Variation among isolates of G. g. var. tri- tici and G. g. var. avenae was minimal. The 3' end and 5' end of the 18S rDNA are conserved among
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use of random amplified polymorphic dna rapd for identification of Gaeumannomyces species
Soil Biology & Biochemistry, 1996Co-Authors: Hanafy M Fouly, Henry T Wilkinson, Leslie L DomierAbstract:Abstract Randomly amplified polymorphic DNAs (RAPD) were used to distinguish among isolates of Gaeumannomyces graminis var. tritici, G. g. var. graminis, G. g. var. avenae, G. incrustans, and G. cylindrosporous. Of 60 random sequence decamer primers tested, 28 produced bands and 15 showed evidence of polymorphism. Four primers produced DNA amplification patterns that were used to distinguish G. graminis, G. incrustans, and G. cylindrosporous. Banding patterns were similar within isolates of G. g. var. tritici, G. g. var. avenae and G. incrustans. G. g. var. graminis showed greater variability in banding patterns. The unweighted pair group method with arithmetical averages (UPGMA) indicated that G. g. var. tritici isolates were more closely related to G. g. var. avenae than to G. g. var. graminis isolates. The results of our study showed that RAPD markers can be used to confirm the identification of Gaeumannomyces species and varieties.
M L Elliott - One of the best experts on this subject based on the ideXlab platform.
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Disease response of bemudagrasses to Gaeumannomyces graminis var.graminis
Plant Disease, 1995Co-Authors: M L ElliottAbstract:A greenhouse study evaluated 28 bermudagrass accessions, 27 from the National Turfgrass Evaluation Program plus the commonly used cultivar Tifdwarf, for their response to the root rot fungus Gaeumannomyces graminis var. graminis, which causes bermudagrass decline of golf course putting greens in Florida. Four isolates of the fungus at three different inoculum levels were used. As evaluated, there appears to be no resistance or tolerance to this fungus among the bermudagrass germ plasm tested. More than one G. g. var. graminis isolate at more than one inoculum level was necessary to make adequate evaluations.
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effect of melanin biosynthesis inhibiting compounds on Gaeumannomyces species
Mycologia, 1995Co-Authors: M L ElliottAbstract:AbstractInhibition of melanin production was observed in Gaeumannomyces isolates treated with DHN-melanin inhibiting compounds (tricyclazole, pyroquilon, fthalide and chlobenthiazone) but not with ...
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effect of systemic fungicides on a bermudagrass putting green infested with Gaeumannomyces graminis var graminis
Plant Disease, 1995Co-Authors: M L ElliottAbstract:During a 3-year period, the systemic fungicides fenarimol, myclobutanil, propiconazole, tebuconazole, thiophanate methyl, and triadimefon were evaluated for efficacy in reversing or preventing the quality decline of a hybrid bermudagrass putting green infested with Gaeumannomyces graminis var. graminis. None of the fungicides increased turfgrass quality over that of the untreated turfgrass, whether used curatively at the highest recommended rates or preventatively at a reduced rate. However, a significant decline in turfgrass quality, when compared with the untreated turfgrass, was often associated with repeated use of the DMI fungicides fenarimol, myclobutanil, propiconazole, and triadimefon but not with the use of the DMI fungicide tebuconazole or with the benzimidazole fungicide thiophanate methyl.
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use of polymerase chain reaction to detect Gaeumannomyces graminis dna in plants grown in artificially and naturally infested soil
Phytopathology, 1993Co-Authors: Joan M Henson, T Goins, W Grey, D E Mathre, M L ElliottAbstract:The polymerase chain reaction was used to specifically amplify DNA of Gaeumannomyces graminis, a filamentous soilborne fungus that causes root and crown disease of cereals and turfgrasses. Nested primers were used to amplify a 188-bp fragment of mitochondrial DNA from fungal and infected-plant samples, which were simply boiled to release target DNA. Fungal DNA was amplified from single boiled hyphal tips or ascospores. G. graminis DNA was also detected in boiled crowns and roots from experimentally and naturally infected wheat, rice, and St. Augustine-grass and experimentally infected bermudagrass []
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Fungi similar to Gaeumannomyces associated with root rot of turfgrasses in Florida
Plant Disease, 1991Co-Authors: M L Elliott, P. J. LandschootAbstract:Dark-pigmented, ectotrophic fungi were isolated from the roots of hybrid bermudagrass with symptoms of bermudagrass decline, a root rot disease. Similar fungi were also isolated from the roots of St. Augustinegrass, centipedegrass, bentgrass, and perennial ryegrass that exhibited root rot symptoms. Gaeumannomyces graminis var. graminis was identified from the roots of bermudagrass, St. Augustinegrass, and a bermudagrass-perennial ryegrass mix. G. incrustans was identified from centipedegrass, bermudagrass, and St. Augustinegrass roots, whereas Magnaporthe poae was identified only from bentgrass roots (.)
D M Weller - One of the best experts on this subject based on the ideXlab platform.
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use of Gaeumannomyces graminis var graminis alone and in combination with fluorescent pseudomonas spp to suppress take all of wheat
Plant Disease, 1995Co-Authors: B K Duffy, D M WellerAbstract:Gaeumannomyces graminis var. graminis, originally isolated from rice, suppressed take-all of wheat caused by Gaeumannomyces graminis var. tritici in growth chamber studies when applied to the soil. Furthermore, combination treatments consisting of G. g. var. graminis applied to the soil and fluorescent Pseudomonas strains applied to the seed, either 30-84, Q29z-80, Q69c-80, or a mixture of strains (Q2-87 plus Q1c-80 plus Q8d-80 plus Q69c-80), were significantly more suppressive of take-all than either treatment used alone. In a winter wheat field trial at Pullman, Wash., G. g. var. graminis applied to the seed furrow significantly reduced crown root infection by G. g. var. tritici and the strain mixture reduced seminal root infection suggesting differential protection at various stages of disease development. However, in contrast to growth chamber studies the combination of G. g. var. graminis and the strain mixture did not enhance take-all suppression in the field compared with the same treatments used alone.
