bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of the Peach Brown Rot Fungus Monilinia fructicola Resistant to Demethylation Inhibitor Fungicides in New Jersey
Authors: Burnett A. , Lalancette N. , McFarland K. 
Published: December 2009

Reduced sensitivity and resistance of Monilinia fructicola to demethylation inhibitors (DMIs; fungicide group 3) have been previously found in stone fruit orchards in Georgia, South Carolina, Ohio, and New York (2). Resistance development is a major concern because of the importance of DMIs for brown rot management. Eleven single-spore isolates, originally collected during 2006 from separate commercial peach (Prunus persica) orchards in southern New Jersey, were removed from cold storage (5°C) in early 2008 and examined in vitro for resistance to the DMI propiconazole (Orbit 3.6EC; Syngenta Crop Protection, Inc., Greensboro, NC). After 19 months at 5°C, isolate 7 was inhibited 53.4% in growth on potato dextrose agar (PDA) amended at the discretionary dose of 0.3 μg/ml propiconazole; inhibition of the remaining isolates ranged from 81.4 to 100%. Inhibition values were based on two replications of eight colonies per isolate performed after incubation at 25°C for 4 days. Because of the previously reported relationship between duration of cold storage and propiconazole sensitivity, isolate 7 was tentatively deemed resistant (1). To confirm the in vitro results, isolates were grown at 25°C for 7 days on cellophane over PDA. Genomic DNA was isolated from mycelium with the DNeasy Plant Mini Kit (Qiagen, Inc., Valencia, CA). PCR with primers INS65-F and INS65-R was conducted on a GeneAmp thermal cycler (Applied Biosystems, Inc., Foster City, CA) as described previously to amplify a 65-bp region named ‘Mona’ associated with DMI resistance (2). PCR products were separated via electrophoresis on 0.8% agarose gel. The primers amplified a 376-bp fragment from isolate 7 and a 311-bp fragment from all other isolates, thus indicating the presence of Mona in isolate 7. Restriction fragment length polymorphism analysis using the BsrBI enzyme, specific to a single restriction site within Mona, was conducted on the amplified fragments from all isolates. Electrophoresis results showed digestion of the 376-bp fragment from isolate 7 into 140-bp and 236-bp fragments, thereby confirming the presence of Mona; none of the 311-bp fragments from the remaining isolates were cut by BsrBI. Although economic loss from brown rot has not been reported in New Jersey, these results show that propiconazole-resistant strains have been detected since 2006 and it is most likely that resistant strains of the pathogen are still present in commercial peach orchards. To combat this risk, current brown rot control recommendations are incorporating quinone outside inhibitors (QoIs; fungicide group 11) and carboxamides (fungicide group 7) into control programs as a resistance management strategy. More extensive sampling is planned to ascertain the prevalence and location of resistant strains. References: (1) K. D. Cox et al. Phytopathology 97:448, 2007. (2) C.-X. Luo et al. Plant Dis. 92:1099, 2008.
First Report of Tobacco ringspot virus in Joe-Pye Weed (Eupatorium purpureum) in Mississippi
Authors: Sabanadzovic S. , Ingram D. M. , Lawrence A. M. 
Published: December 2009

Eupatorium purpureum L. (joe-pye weed, sweet joe-pye weed, and sweetscented joe-pye weed) is a wildflower perennial plant native to the eastern United States. In May 2006, virus-like symptoms including systemic chlorosis, mottling, and downward rolling of leaf blades were observed in a joe-pye weed plant located on the Mississippi State University campus. Young symptomatic leaves were ground in 0.1 M phosphate buffer, pH 7.2, and the slurry was inoculated on leaves of several herbaceous hosts grown in a greenhouse. Systemic symptoms were observed 1 to 2 weeks postinoculation in Cucumis sativus (chlorotic spots followed by systemic ringspot and leaf deformation), Chenopodium quinoa (necrotic lesions/leaf deformation), Nicotiana benthamiana (mosaic/line patterns), and N. rustica (necrotic ring spots). Electron microscopy of partially purified preparations from infected joe-pye weed and cucumber plants revealed the presence of intact and empty isometric viral particles of approximately 30 nm in diameter resembling nepoviruses or comoviruses. The original joe-pye weed plant and artificially infected herbaceous plants were tested by ELISA (Agdia Inc., Elkhart, IN) for several nepoviruses/comoviruses and found to be positive for Tobacco ringspot virus (TRSV; genus Nepovirus, family Comoviridae). Total RNA extracted from the original virus source plant was reverse transcribed using oligodT primer and submitted to PCR with the primer set TRS-F (5′TATCCCTATGTGCTTGAGAG3′) and TRS-R (5′CATAGACCACCAGAGTCACA3′) designed from the published sequences in GenBank of the RNA 1 of Tobacco ringspot virus. A specific 766-bp PCR product was cloned and sequenced. Sequence analysis showed that the virus from the joe-pye weed shared 94% nucleotide identity (98% at amino acid level) with a “bud blight” isolate of TRSV (Accession No U50869) (2) in the sequenced genome portion and slightly lower (90 to 92%) with other sequenced isolates of the same virus, thus further confirming the identity of the virus. In 2008 and 2009, TRSV was detected in an additional 16 symptomatic specimens of the same host collected from six distinct locations in Mississippi. Our results show that E. purpureum is a new host for TRSV. Considering that the related plant species E. capillifolium (small dogfennel) was already reported as a host of TRSV in North Carolina (1), this suggests that these two common plants may represent additional reservoirs of this virus in the region. References: (1) M. C. Rush and G. V. Gooding. Phytopathology 60:1756, 1970, (2) P. A. Zalloua et al. Virology 219:1, 1996.
First Report of Myrothecium Leaf Spot of Common Bean in China Caused by Myrothecium roridum
Authors: Zhao Y.-J. , Li B.-J. , Shi Y.-X. , Xie X.-W. 
Published: December 2009

Common bean (Phaseolus vulgaris L.) is an economically important crop in China. In June 2008, a new foliar disease was observed on beans in Shunyi District, Beijing, China. The disease occurred in approximately 15% of the plants in a commercial field. Leaf spots were circular to irregular, reddish brown, zonate, and 8 to 20 mm in diameter. Black sporodochia with white tuffs were present on older lesions and black spore masses were present in moist weather. Ten isolates recovered from lesions produced white, floccose colonies and spore masses after 4 days on potato dextrose agar. The rod-shaped, hyaline conidia had rounded ends and averaged 6.8 × 2.5 μm. All characteristics were consistent with the description of Myrothecium roridum Tode ex Fr. (1). The internal transcribed spacer regions of one isolate were sequenced and deposited in GenBank (Accession No. GQ 381291). Sequences of the isolate from bean in China were 98% similar to sequences of M. roridum in GenBank. To determine pathogenicity, 30 healthy seedlings of common bean were inoculated by spraying a 1 × 105 conidia ml–1 suspension of M. roridum onto the foliage. Ten seedlings were sprayed with sterile water and served as controls. Plants were kept in a humid chamber at 27°C overnight and then placed in a growth chamber. After 6 days, the symptoms described above were observed on leaves in all inoculated plants, whereas symptoms did not develop on the control plants. The pathogen was reisolated from inoculated leaves, fulfilling Koch's postulates. There is one report of M. roridum on soybean in Korea (2). To our knowledge, this is the first report of Myrothecium leaf spot on common bean in China. References: (1) M. Fitton et al. CMI Mycol. Pap. No. 253, 1970. (2) K. J. Yum et al. Plant Pathol. J. 6:313, 1990.
First Report of Fruit Rot Disease of Mango Caused by Botryosphaeria dothidea and Neofusicoccum mangiferae in Taiwan
Authors: Ni H. F. , Liou R. F. , Hung T. H. , Chen R. S. , Yang H. R. 
Published: December 2009

Mango (Mangifera indica L.) is an economically important fruit crop in the tropical and subtropical areas of the world. In southern Taiwan, mango is grown on 18,000 ha of hilly land mainly located in Tainan, Kaohsiung, and Pingtung. Tons (180,000) of mango with a value of NT$6.6 billion (US$206 million) are produced annually. In 2008, mango fruit rot disease was observed 1 week after harvest on 30 to 72% of stored mangoes collected from seven orchards in southern Taiwan. The initial symptom was a small, brown lesion and rot symptoms advanced progressively. Two predominant fungi were isolated from the margin of lesions on acidified potato dextrose agar (PDA with lactic acid, pH 3.8). Isolates of each fungal type were transferred to 2% water agar containing sterilized pine needles and exposed to near UV light to induce sporulation. For the first fungus, conidia obtained from pycnidia were ovate, one-celled, and hyaline, with an average length and width of 12.93 ± 0.93 × 6.98 ± 0.40 μm and an average length/width ratio of 1.85. To confirm the identity of the fungus, PCR amplification by universal primers, ITS1/ITS4, and DNA sequencing of the internal transcribed spacer (ITS1-5.8S-ITS2 rRNA gene cluster) were conducted. The internal transcribed spacer (ITS) sequence of ribosomal DNA of this fungus was analyzed and submitted to GenBank (Accession No. GQ421486). It showed a sequence identity of 100% with Neofusicoccum mangiferae (Syd. & P. Syd.) Crous, Slippers & A. J. L. Phillips) (GenBank Accession No. AY615185). For the second fungus, conidia obtained from pycnidia were fusiform, one-celled, and hyaline, with an average length and width of 22.87 ± 1.32 × 6.42 ± 0.46 μm and a length/width ratio of 3.53. The ITS sequence of ribosomal DNA of this fungus was analyzed and submitted to GenBank (Accession No. GQ421485). It showed a sequence identity of 100% with Botryosphaeria dothidea (Moug.: Fr.) Ces & De Not.) (GenBank Accession No. AY 786321). To test pathogenicity, four mango fruits were wounded with a sterile needle, inoculated with mycelium agar plugs (0.5 mm in diameter) excised from separate monoconidial cultures, and incubated in a plastic box with a 100% relative humidity for 2 days at room temperature. Brown lesions appeared on all wounded sites of each fungus 2 days postinoculation. In control experiments, sterile agar plugs were placed on the wounded mango fruits. These fruits remained completely free from symptoms throughout the experiment. The pathogen was reisolated from the lesions of inoculated fruits and identified as N. mangiferae and B. dothidea, thus fulfilling Koch's postulates. N. mangiferae and B. dothidea have been reported on mango trees in Australia and South Africa (1). To our knowledge, this is the first report of these fungi causing fruit rot of mango in Taiwan. References: (1) B. Slippers et al. Mycologia 97:99, 2005.
First Report of Grapevine leafroll-associated virus 4 and 5 in Grapevines in China
Authors: Pei G.-Q. , Dong Y.-F. , Zhang Z.-P. , Fan X.-D. 
Published: December 2009

Grapevine leafroll disease (GLD) is one of the most important diseases of grapevines worldwide. Nine serologically distinct viruses in the Closteroviridae family are associated with GLD. Previous studies reported that Grapevine leafroll-associated virus (GLRaV) -1, -2, -3, and -7 were present in grapevines in China with GLRaV-1 and -3 the predominant viruses associated with GLD (1). To confirm if GLRaV-4 and -5 were also present in China, 36 dormant canes from individual vines of 29 cultivars that showed GLD leaf symptoms during the growing season were collected from the germplasm collection plot of the Research Institute of Pomology, Chinese Academy of Agricultural Sciences. Total RNA extracted by a silica capture protocol (2) from phloem-enriched bark of 36 samples was tested separately for GLRaV-4 and -5 by reverse transcription (RT)-PCR using virus-specific primers. Primers LR4F (5′-ACATTCTCCACCTTGTGCTTTT-3′) and LR4R (5′-CATACAAGCGAGTGCAATTAC-3′) (4) were used to amplify a 321-bp fragment corresponding to a partial region of the HSP70 gene from GLRaV-4. One sample from cv. Autumn Royal was infected by GLRaV-4. The amplicon was cloned and a single clone was sequenced (GenBank Accession No. GQ246624) that showed 99% nucleotide identity with a corresponding region of a GLRaV-4 isolate from the United States (Accession No. AF039553). Since antiserum specific to GLRaV-4 was unavailable, a second pair of primers, LR4CP-F (5′-GGTGTCCAGCGCTTCCAA-3′) and LR4CP-R (5′-GCCAGAGAAGCATCGTAA-3′), was designed on the basis of the sequence of GLRaV-4 from Chile (Accession No. EU746620) that amplified a 300-bp fragment specific to the coat protein gene of GLRaV-4. The amplicon was cloned and a single sequence (Accession No. GQ479041) was compared with a corresponding nucleotide sequence of GLRaV-4 from Chile (Accession No. EU746621) showing 99% identity. A sample from cv. Malaga Rose was positive when tested by ELISA with antibodies specific to GLRaV-5 (Neogen Europe, Ltd. Scotland, UK) and this was confirmed by amplification of a 690-bp fragment corresponding to the GLRaV-5 coat protein gene using virus-specific primers LR5F (5′-CCCGTGATACAAGGTAGGACA-3′) and LR5R (5′-CAGACTTCACCTCCTGTTAC-3′) (3). The amplicon was cloned and a single clone was sequenced (Accession No. GQ246625) that showed 95% nucleotide identity with the CP gene sequence of GLRaV-5 from Argentina (Accession No. EU815935). To our knowledge, this is the first report of GLRaV-4 and -5 in grapevines in China. Confirmation of these viruses in China is very important for producing virus-free plants and this information also will be helpful in developing a multiplex RT-PCR assay to simultaneously detect multiple GLRaVs and helpful with studies on the molecular variability of these viruses. References: (1) Y. Dong et al. China Fruits 6:9, 2005. (2) X. Foissac et al. Acta Hortic. 550, 37, 2001. (3) X. Good and J. Monis. Phytopathology 91:274, 2001. (4) F. Osman et al. J. Virol. Methods 141:22, 2007.
First Report of Tobacco rattle virus Associated with Corky Ringspot in Potatoes Grown in North Dakota
Authors: David N. , Mallik I. , Gudmestad N. C. 
Published: December 2009

Tobacco rattle virus (TRV) belongs to the genus Tobravirus and causes a stem mottle of potato (Solanum tuberosum) foliage and necrotic arcs and rings in tubers referred to as corky ringspot. This virus is generally transmitted by a number of species of stubby-root nematode. The virus is widespread and has been reported in California, Colorado, Florida, Idaho, Michigan, Oregon, Washington, Minnesota, and Wisconsin (2). In the spring of 2009, we received potato tubers of cv. Russet Burbank with internal necrotic arcs very similar to those caused by TRV from potato storages located in Grand Forks and Dickey counties of North Dakota. Total RNA was extracted from the necrotic lesions of two tubers from each location using the Total RNA Isolation kit (Promega Corp., Madison WI). These extracts were tested for TRV by reverse transcription (RT)-PCR using primers complementary to nucleotides 6555 to 6575 (Primer A) and identical to nucleotides 6113 to 6132 (Primer B) within the 3′ terminus of TRV-SYM RNA-1 (GenBank Accession No. X06172) (3). The expected 463-bp amplicons from two separate tuber samples from each county were cloned (TOPO Cloning; Invitrogen, Carlsbad, CA) and sequenced. The sequences obtained from the four clones at both locations were found to be identical to each other and were 99% identical to the corresponding regions of TRV isolates from Michigan and Florida (GenBank Accession Nos. EU315226.1 and AF055912.1, respectively). Since sequences from all four clones were identical, only one of the sequences was submitted to Genbank (Accession No. GQ223114) and thus represents a consensus sequence. The extracts also tested positive in RT-PCR with a second set of primers corresponding to sequences in TRV RNA-2 yielding a 3.8-kbp amplicon (1). No evidence was found by RT-PCR for several other viruses that cause tuber necrosis in potato (Potato mop top virus, Tomato spotted wilt virus, Alfalfa mosaic virus, and tuber necrosis strains of Potato virus Y). The virus was mechanically transmitted by inoculating sap from symptomatic tubers from both counties to tobacco cv. Samsun NN, which showed typical bright yellow patches and spots on leaves 2 weeks postinoculation. TRV was confirmed in tobacco by RT-PCR from total RNA extracted from tobacco leaves with both sets of the aforementioned primers. To our knowledge, this is the first report of TRV in North Dakota and the first report of corky ringspot disease of potato in this state. References: (1) J. M. Crosslin et al. Virus Res. 96:99, 2003. (2) N. C. Gudmestad et al. Plant Dis. 92:1254, 2008. (3) D. J. Robinson. J. Virol. Methods 40:57, 1992.
First Report of Southern Blight on Silverbush (Convolvulus cneorum) Caused by Sclerotium rolfsii in Italy
Authors: Polizzi G. , Aiello D. , Guarnaccia V. , Parlavecchio G. , Vitale A. 
Published: December 2009

The genus Convolvulus has more than 200 species that are encountered in temperate to tropical climates all around the world. Convolvulus cneorum L., also known as silverbush, is a perennial shrub native to southern Europe (Sicily and Croatia) with dense, silver foliage and masses of large, circular, white flowers. During July of 2009, a widespread blight was observed on approximately 10% of 12,000 4-month-old potted silverbush plants. The plants were obtained from cuttings and produced by a commercial nursery in eastern Sicily, Italy. Symptomatic plants initially had sunken, tan lesions at the ground level that developed into typical southern blight. Circular and crescent-shaped patches were observed on the masses of weeds on the surface of the containers where silverbush were grown. At the soil line, white mycelia and small (1 to 2 mm in diameter), brown, spherical sclerotia with internally differentiated rind, cortex, and medulla characteristic of Sclerotium rolfsii Sacc. were observed. Crown and stem lesions were surface disinfested (1% NaOCl) for 1 min, rinsed in sterile water, and placed on potato dextrose agar. Isolation consistently yielded colonies of Sclerotium rolfsii (teleomorph Athelia rolfsii (Curzi) Tu & Kimbrough) with typical sclerotia produced within 6 to 7 days (2). Pathogenicity tests were performed on 20 plants by placing 10 sclerotia obtained from 10-days-old cultures in the soil below the crown portion on each of 5-month-old healthy cuttings of silverbush. The same number of plants served as noninoculated controls. All plants were maintained in a growth chamber at 25 ± 1°C and enclosed for 7 days in polyethylene bags. Plants were then moved to a greenhouse where temperatures ranged from 24 to 28°C. Symptoms of southern blight developed after 7 to 20 days on all inoculated plants. Control plants remained symptomless. S. rolfsii was reisolated from symptomatic plants. S. rolfsii was reported for the first time in Sicily in 2004 in an ornamental nursery (1). To our knowledge, this is the first report in the world of S. rolfsii on silverbush and it is the first outbreak of southern blight on Convolvulus species. The high susceptibility of silverbush to the pathogen could be a limiting factor for the cultivation in nursery of this indigenous wildflower plant. References: (1) G. Polizzi et al. Plant Dis. 88:310, 2004. (2) Z. K. Punja and A. Damiani. Mycologia 88:694, 1996.
First Report of Powdery Mildew Caused by Leveillula taurica on Giant Blazing Star (Mentzelia laevicaulis)
Authors: Sampangi R. K. , Glawe D. A. , Barlow T. , Mohan S. K. 
Published: December 2009

Mentzelia laevicaulis (Dougl. ex Hook.) Torr. & Gray (Loasaceae; common names are giant blazing star and smoothstem blazing star) is widely distributed throughout western North America in sites ranging from lowland deserts to mountainous areas in Canada and the United States. During a plant disease survey in June 2007 in the Owyhee Mountains, Canyon County, Idaho, leaves of M. laevicaulis displaying whitish, mycelial growth were collected from plants growing on stream banks and gravelly road embankments. Diseased leaves exhibited localized, chlorotic discolorations associated with signs of a powdery mildew. Of approximately 20 plants at the site, 50% were infected. White mycelia and conidia were more abundant on the adaxial leaf surfaces than on the abaxial surfaces. Severely diseased leaves were buckled and slightly twisted. By August and through September, sporulation was greatest on mature plants, and lowermost leaves were completely covered with flocculose, dense, white mycelia. Dimorphic conidia were lanceolate or cylindrical and measured (44-) 46 to 67 (-71) × (14-) 14.5 to 20 (-21) μm. DNA was extracted and PCR was used to amplify the internal transcribed spacer (ITS) region as described previously (2), except that primers ITS 5 and P3 (4) were used. The resulting 633-bp sequence (GenBank Accession No. GQ860947) included a 616-bp region identical to a sequence reported previously for Leveillula taurica (Lév.) Arnaud from eastern Washington (GenBank No. AY912077), as well as ITS regions from L. taurica previously reported from Iran (GenBank No. AB048350) (2) and Australia (GenBank No. AF 073351) (2). Based on the ITS sequence, the present fungus grouped within Khodaparast et al. (3) Clade 1 that included L. taurica strains they distinguished from other, superficially similar species of Leveillula. On the basis of morphological and sequence data, the fungus was determined to be L. taurica (1,3). A voucher specimen was deposited in the Mycology Herbarium (WSP) at Washington State University. To our knowledge, this is the first report of a named powdery mildew species from a member of the Loasaceae. The only previous report of a powdery mildew on a loasaceous host was an undetermined Oidium sp. on a species of Mentzelia (1). The discovery of L. taurica on a previously unknown native host species is further evidence that this introduced pathogen is becoming endemic to the Pacific Northwest. Native host species, such as M. laevicaulis, may play a role in the epidemiology of powdery mildew diseases caused by L. taurica on crop and ornamental species in the Pacific Northwest. References: (1) U. Braun. Beih. Nova Hedwigia 89:1, 1987. (2) D. A. Glawe et al. Mycol. Prog. 4:291, 2005. (3) S. A. Khodaparast et al. Mycol. Res. 105:909, 2001. (4) S. Takamatsu and Y. Kano. Mycoscience 42:135, 2001.