bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of Leek yellow stripe virus in Garlic in the State of Guanajuato, Mexico
Authors: Pérez-Moreno L. , Córdova-Rosales Z. , Barboza-Corona E. , Ramírez-Malagón Rafael , Ramírez-Lúa J. , Ruiz-Castro S. , Silva-Rosales L. 
Published: May 2007

Garlic (Allium sativum L.) can be affected by a virus complex (1) consisting of two potyviruses, Onion yellow dwarf virus (OYDV) and Leek yellow stripe virus (LYSV), and two carlaviruses, Garlic common latent virus (GCLV) and Shallot latent virus (SLV) (1). To identify the components of the virus complex that could be present in garlic plants in Guanajuato State, which is the second largest garlic producer in the country and where presumptive viral symptoms were initially observed in December 2004, a survey was carried out in six locations: San Miguel de Allende and San Luis de la Paz in northern Guanajuato; Irapuato and Villagrán in the central region; and Salamanca and Valle de Santiago in the southern part of the state. Enzyme-linked immunosorbent assay (ELISA) was carried out to detect LYSV, OYDV, GCLV, and SLV in 195 garlic leaf samples collected during January 2005 from plants with leaf yellow stripe, mosaic, enation, deformation, or dwarfism symptoms. A set of primers, previously reported and specific to the coat protein cistron of LYSV (1), were synthesized and used in a reverse transcriptase-polymerase chain reaction (RT-PCR). The amplified product (1,020 nucleotides) was cloned into plasmid pGEM T-Easy (Promega, Madison, WI) and sequenced (Gen-bank Accession No. DQ841554). Sequence analysis showed that the cloned DNA fragment shared 97% similarity with the coat protein cistron of LYSV isolate no. 3 from Okinawa (GenBank Accession No. AB194632). The fragment was then radioactively labelled and used as a probe in the RNA blot analysis of all samples to confirm the ELISA results of LYSV. Of the 195 samples, 64 tested positive by RNA blot analysis. Forty-one of these were also positive by ELISA for LYSV. Preliminary, positive ELISA results were also obtained for OYDV, GCLV and SLV. To our knowledge, this is the first report of LYSV in the State of Guanajuato and in Mexico. The correct identification of viruses present in garlic will help to use the appropriate strategies to reduce viral incidence in this garlic-producing region. Reference: (1) T. V. M. Fajardo et al. Fitopatol. Bras. 26:619, 2001.
A New Report of Cymbidium spp. Pseudobulb Rot Orchestrated by Erwinia carotovora, Fusarium oxysporum, and Mucor hiemalis f. sp. hiemalis
Authors: Sen S. , Acharya R. , Saha A. , Acharya K. 
Published: May 2007

Cymbidium spp. is an orchid of great horticultural value cultivated extensively in Eastern Himalaya, India. Since 1995, growers have experienced huge crop losses in every monsoon month because of pseudobulb rot. Pseudobulbs initially turned soft and pulpy followed by oozing of a dark brown liquid with a foul odor (early phase). With increasing severity, the bulbs and roots lose weight as the internal tissues gradually disintegrate (middle phase). Finally, the bulb becomes hollow, fibrous, and dry causing death of the plant (later phase). Surveys from 2002 to 2005 showed that disease incidence ranged from 60 to 100%. Rotted tissue was plated on nutrient agar and potato dextrose agar media. Three organisms were consistently isolated from 50 samples collected from 30 different localities. They were identified as Erwinia carotovora (2), Fusarium oxysporum (3), and Mucor hiemalis f. sp. hiemalis (1) and were predominant at the earlier, middle, and later stages of disease, respectively. Identifications were further confirmed by the Agricultural Research Institute (ARI), Pune, India. Pseudobulbs were surface sterilized with 0.5% sodium hypochlorite for 1 min, washed by sterile distilled water, and dipped separately into three different spore/cell suspensions (105 CFU/ml) for 1 min. Another set of sterilized bulbs was dipped first into E. carotovora, then into F. oxysporum 12 days later, and then into M. hiemalis f. sp. hiemalis 15 days after the second dip. For the control set, bulbs were dipped into sterile distilled water. Samples were incubated aseptically at 20°C with a relative humidity of 80%, and all inoculated bulbs were evaluated for disease 47 days after the first inoculation. When samples were inoculated separately, E. carotovora exhibited maximum (70%) tissue disintegration followed by F. oxysporum (30%) and M. hiemalis f. sp. hiemalis (10%), but none of the individual pathogens caused 100% tissue disintegration. Complete destruction was observed after 47 days of first inoculation when these three pathogens were inoculated consecutively according to their serial occurrence. It is an interesting report on host-pathogen combination as three pathogens act in sequence toward ultimate demolition of the host. We report this rot as a synergistic activity of three pathogens to cause an uncontrolled epidemic disease of Cymbidium spp. References: (1) J. C. Gilman. Page 37 in: A Manual of Soil Fungi. Iowa State College Press. Ames, IA, 1945. (2) J. G. Holt. Page 469 in: Bergey's Manual of Systematic Bacteriology. Vol. I. Williams and Wilkins. Baltimore/London, 1984, (3) C. V. Subramaniam. Page 657 in: Hyphomycetes. Indian Council of Agricultural Research (ICAR). New Delhi, 1971.
First Report of Grapevine leafroll associated virus-3 in American Vitis spp. Grapevines in Washington State
Authors: Soule M. J. , Eastwell K. C. , Naidu R. A. 
Published: May 2007

Washington State is the largest producer of juice grapes (Vitis labruscana ‘Concord’ and Vitis labrusca ‘Niagara’) and ranks second in wine grape production in the United States. Grapevine leafroll disease (GLD) is the most wide spread and economically significant virus disease in wine grapes in the state. Previous studies (2) have shown that Grapevine leafroll associated virus-3 (GLRaV-3) is the predominant virus associated with GLD. However, little is known about the incidence and economic impact of GLD on juice and table grapes. Because typical GLD symptoms may not be obvious among these cultivars, the prevalence and economic impact of GLD in Concord and Niagara, the most widely planted cultivars in Washington State, has received little attention from the grape and nursery industries. During the 2005 growing season, 32 samples from three vineyards and one nursery of ‘Concord’ and three samples from one nursery of ‘Niagara’ were collected randomly. Petiole extracts were tested by single-tube reverse transcription-polymerase chain reaction (RT-PCR; 3) with primers LC 1 (5′-CGC TAG GGC TGT GGA AGT ATT-3′) and LC 2 (5′-GTT GTC CCG GGT ACC AGA TAT-3′), specific for the heat shock protein 70 homologue (Hsp70h gene) of GLRaV-3 (GenBank Accession No. AF037268). One ‘Niagara’ nursery sample and eleven ‘Concord’ samples from the three vineyards tested positive for GLRaV-3, producing a single band of the expected size of 546 bp. The ‘Niagara’ and six of the ‘Concord’ RT-PCR products were cloned in pCR2.1 (Invitrogen Corp, Carlsbad, CA) and the sequences (GenBank Accession Nos. DQ780885, DQ780886, DQ780887, DQ780888, DQ780889, DQ780890, and DQ780891) compared with the respective sequence of a New York isolate of GLRaV-3 (GenBank Accession No. AF037268). The analysis revealed that GLRaV-3 isolates from ‘Concord’ and ‘Niagara’ share nucleotide identities of 94 to 98% and amino acid identities and similarities of 97 to 98% with the Hsp70h gene homologue of the New York isolate of GLRaV-3. Additional testing by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) using antibodies specific to GLRaV-3 (BIOREBA AG, Reinach, Switzerland) further confirmed these results in the ‘Niagara’ and two of the ‘Concord’ isolates. GLRaV-3 has previously been reported in labrusca cvs. Concord and Niagara in western New York (4) and Canada (1), but to our knowledge, this is the first report of GLRaV-3 in American grapevine species in the Pacific Northwest. Because wine and juice grapes are widely grown in proximity to each other in Washington State and grape mealybug (Pseudococcus maritimus), the putative vector of GLRaV-3, is present in the state vineyards, further studies will focus on the role of American grapevine species in the epidemiology of GLD. References: (1) D. J. MacKenzie et al. Plant Dis. 80:955, 1996. (2) R. R. Martin et al. Plant Dis. 89:763, 2005. (3) A. Rowhani et al. ICGV, Extended Abstracts, 13:148, 2000. (4) W. F. Wilcox et al. Plant Dis. 82:1062, 1998.
First Report of Blueberry Leaf Spot Caused by Cylindrocladium colhounii in China
Authors: Luan Y. S. , Feng L. , An L. J. 
Published: May 2007

During late July and early August of 2005, leaf spot symptoms were observed in a blueberry nursery at a plantation in Dalian, which to our knowledge, lies within the largest blueberry-production area in China. Symptoms were observed primarily on lowbush species, for example Blomidon, as well as half-highbush cultivars. A slow-growing, white mycelium from the margin of necrotic leaf spots was recovered on potato dextrose agar (PDA). The following morphological traits were observed: erect conidiophores that branch twice and were terminated in a stiped, clavate phialide; hyaline, cylindrical, four-celled conidia; and globose, reddish brown, aggregated chlamydospores. Conidiophores (including stipes and terminal phialides) were 305 to 420 × 5 to 9 μm; primary branches were 9 to 45 × 5 to 6.3 μm; secondary branches were 9 to 17.3 × 3.1 to 4.5 μm; phialides were 7.8 to 17.5 × 2.5 to 6 μm; stipes (from the highest branch area to vesicle) were 150 to 270 μm long; and vesicles were 13 to 30 × 2 to 4.5 μm. Conidia were 50 to 72 × 4 to 5.5 μm. Chlamydospores were 15 to 20 μm in diameter. Koch's postulates were fulfilled by spray inoculating two healthy cultivars with conidiophores homogenized in axenic water. As a control, two healthy plants were sprayed with axenic water. Plants were placed inside plastic bags to maintain humidity and incubated in a growth chamber at 26°C under fluorescent light for 14 h and 20°C in darkness for 10 h. After 2 days, the plastic bags were removed and plants were maintained under the same conditions. After 4 days, small-to-medium brown spots with purplish margins were observed on the adaxial side of leaves from inoculated plants, but not from control plants. Fungi isolated from these lesions had the same morphological traits as the ones isolated previously from field plants. The morphological descriptions and measurements were similar to Cylindorocladium colhounii (2). The 5.8S subunit and flanking internal transcribed spacers (ITS1 and ITS2) of rDNA and the β-tubulin gene were amplified from DNA extracted from single-spore cultures using the ITS1/ITS4 primers and T1/Bt2b primers, respectively, and sequenced (1). The ITS and β-tubulin gene sequences were similar to C. colhounii STE-U 1237 (99%; GenBank Accession No. AF231953) and C. colhounii STE-U 705 (99%; GenBank Accession No. AF231954), respectively. The morphology, secondary conidiation, and sequences of ITS and β-tubulin gene identify the causal fungus as C. colhounii. To our knowledge, this is the first report of C. colhounii on blueberry in China or in the world. References: (1) P. W. Crous et al. Can. J. Bot. 77:1813, 1999. (2) T. Watanabe. Page 222 in: Dictorial Atlas of Soil and Seed Fungi. CRC Press, Inc., Boca Raton, Fl, 1994.
Phytophthora infestans Mating Types on Tomato (Solanum lycopersicum) in Southern Spain
Authors: Segura J. M. , de Cara M. , Santos M. , Tello J. 
Published: May 2007

During 2004, an unusual spread of Phytophthora infestans on tomato plants in greenhouses located in Almería and Granada provinces, southern Spain, was observed. Infected plants had water-soaked, brown spots on leaves and stems and necrotic areas with white mold on the surface of fruits. Three isolates were obtained by plating diseased tissue on V8 juice agar medium and maintained on rye agar at 18°C. These isolates were analyzed for the mating type. Crosses were carried out using V8 juice agar and rye agar. The two parental isolates US1 (A1) and US8 (A2) were both provided by W. E. Fry, Cornell University, Ithaca, NY. Two of the Spanish isolates were homothallic and the other isolate belonged to the uncommon mating type A1A2. To confirm the occurrence of the two mating types, 43 single-sporangium progeny were produced and analyzed from the A1A2 mating type. Thirty eight isolates were A1, two were A2, one was A1A2 mating type, and two were sterile. Assessment of five single-sporangium progeny from the homothallic type resulted in two A1, two homothallic, and one sterile isolate. A1A2 isolates produced oospores when crossed with either A1 or A2, but not when self-crossed. Previously, the A1A2 mating type has been found in Israel in the field and was obtained from oospores produced on tomato seeds (2,3). Since 2003, mating types of P. infestans isolates recovered from potato (60) and tomato (8) in southern Spain have been characterized. Seventy-five percent of the isolates recovered from potato were A1 and 25% were A2 mating types. Isolates recovered from tomato were 50% A1 and 50% A2 (1). To our knowledge, this is the first report of the occurrence of the A1A2 mating type and homothallic P. infestans isolates on tomato in Spain. References: (1) E. Andujar et al. Congr. Sociedad Española de Fitopatol. 12:244, 2004. (2) E. Rubin and Y. Cohen. Phytoparasitica 32:237, 2004. (3) E. Rubin and Y. Cohen. Plant Dis. 90:741, 2006.
First Report of Tomato (Lycopersicon esculentum) Pith Necrosis Caused by Pseudomonas fluorescens and P. corrugata in the Kingdom of Saudi Arabia
Authors: Molan Y. , Ibrahim Y. 
Published: May 2007

From 2002 to 2004, tomato (Lycopersicon esculentum) plants with external stem lesions, adventitious roots, and necrotic pith that was hollowed or chambered were received by the Clinical Lab of the Plant Protection Department from eight greenhouses in the Riyadh, Abha, and El-Kharj regions of Saudi Arabia. Bacteria were isolated on nutrient agar or King's medium B (KMB) from the stems of tomato plants cv. Red Gold, the cultivar most commonly grown in greenhouses. Gram-negative, rod-shaped bacteria were consistently isolated from stems with symptoms of pith necrosis. They were identified as Pseudomonas fluorescens (biotype I) and P. corrugata on the basis of morphological, physiological, and biochemical tests (2). Isolates of P. fluorescens isolated from Abha and El-Kharj were fluorescent on KMB, aerobic, and positive for oxidase, arginine dihydrolase, and gelatin liquefaction. Furthermore, all isolates produced levan-type colonies on sucrose nutrient agar and utilized glucose, 2-ketogluconate, sucrose, and sorbitol. They were negative for tobacco hypersensitivity and nitrate reduction. The strains of P. corrugata isolated from Riyadh were nonfluorescent, aerobic, and positive for oxidase, nitrate reductase, arginine dihydrolase, and utilization of malonate, alanine, trehalose, arginine, mannitol, and m-inositol. They were negative for levan, pectinase, tobacco hypersensitivity, and utilization of cellobiose and sorbitol. The identity of bacterial species was confirmed by Biolog analysis (carbon source utilization at 37°C), with a similarity index of 0.75 for P. corrugata and 0.71 for P. fluorescens. Four-week-old tomato plants (cv. Red Gold) were inoculated by injecting 50 μl of a bacterial suspension into the axils of the first true leaves. The bacterial suspension was prepared from 24-h-old cultures with sterile distilled water. Sterile distilled water was used as the negative control. After inoculation, plants were covered with polyethylene bags for 24 h to maintain high humidity at 25°C (1). Necrotic lesions surrounding injection points were observed 14 days after inoculation. At 4 weeks after inoculation, all inoculated plants showed symptoms of necrotic pith similar to those observed on the samples received. Control plants injected with water remained healthy throughout the experiments. Isolates of P. fluorescens (biotype I) and P. corrugata were reisolated from inoculated plants and were identical to the original strains on the basis of Biolog analysis. To our knowledge, this is the first report of tomato pith necrosis in Saudi Arabia. References: (1) G. Demir. J. Turk. Phytopathol. 19:63, 1990. (2) R. A. Lelliott and D. E. Stead. Methods for the Diagnosis of Bacterial Diseases of Plants. Blackwell Scientific Publications. Oxford, UK, 1987.
Tobacco ringspot virus Found in the Cardboard Cycad (Zamia furfuracea) in Florida
Authors: Baker C. A. , Adkins S. 
Published: May 2007

Zamia furfuracea (Zamiaceae) is native of coastal Mexico. It is a popular houseplant and easy to grow outdoors in warm climates. In November 2005, a plant of Z. furfuracea, originally from Texas, was received at the Division of Plant Industry in Gainesville, FL. The plant had numerous chlorotic spots on the leaves that eventually became necrotic. Leaves were ground in phosphate buffer (pH 7.2) with Carborundum and used to inoculate a host range that included Chenopodium amaranticolor, C. quinoa, Gomphrena globosa, Datura stramonium, and Nicotiana benthamiana. Systemic symptoms were seen in C. quinoa (necrotic lesions), G. globosa (stunting), D. stramonium (chlorotic ringspots), and N. benthamiana (wavy line patterns) 1 to 2 weeks after inoculation. C. amaranticolor showed only small necrotic local lesions. In further host range studies, systemic infections of Beta vulgaris, D. metaloides, Lactuca sativa, N. clevelandii, Pisum sativus, Petunia hybrida, Zinnia elegans (symptomless), and Cucumis sativa were observed. However, no infection of Zea mays, Verbena hybrida, Glycine max, Phaseolus vulgaris, Catharanthus roseus, Arachis hypogaea, Trifolium spp., Vigna unguiculata, Vicia faba or Digitalis spp. was detected. Inclusions observed in leaf strips of N. benthamiana and D. stramonium indicated a possible infection of this plant with a nepovirus (1). A 337-bp fragment was amplified from total RNA isolated from an inoculated D. stramonium using reverse transcription-PCR with nepovirus group primers provided by Agdia Inc. (Elkhart, IN). Sequence analysis indicated that the nucleotide (nt) and deduced amino acid (aa) sequences of the fragment were 89 to 91% and 91 to 95% identical, respectively, to sequences of the RNA-dependent RNA polymerase gene for Tobacco ringspot virus (TRSV) contained in GenBank (Accession Nos. U50869 and AJ698718). This region was only 50% (nt) and 38% (aa) identical to Cycas necrotic stunt virus (GenBank Accession No. NC_003791), a nepovirus previously reported to infect cycads (2). The original plant, symptomatic inoculated hosts, and the symptomless zinnia tested positive by double-antibody sandwich-ELISA using commercially available antiserum for TRSV (Agdia, Inc.), further confirming the presence of TRSV. Although the virus infecting Z. furfuracea has a more restricted host range than that reported for TRSV, the serology and gene sequence indicates that this virus is a unique isolate of TRSV. References: (1) J. R. Edwardson and R. G. Christie. University of Florida, Institute of Food and Agricultural Sciences, Bull. 894. 1996. (2) S. S. Han et al. Arch. Virol. 147:2207, 2002.
First Report of Trichodorus similis from the Czech Republic (Nematoda: Trichodoridae)
Authors: Kumari S. , Vohanka J. , Decraemer W. 
Published: May 2007

Members of the Trichodoridae can cause substantial crop losses directly by feeding on plant roots and indirectly as vectors of tobraviruses; both vector and virus are polyphagous. Although trichodorid nematodes are important pests of agricultural crops, no data are available on the presence or extent of these nematodes in the Czech Republic. In June 2005, three soil samples from the rhizosphere of a Quercus sp. at Cerveny Vrch yielded a population of Trichodorus similis Seinhorst, 1963. Specimens were extracted from soil by a decanting-sieving method, heat killed, and fixed in triethanolamine formalin (TAF), and processed and mounted in anhydrous glycerin. Nematodes were identified by morphological and morphometrical characters (2). Classical identification of these nematodes was further verified by molecular study. A single, male specimen was temporarily mounted in distilled water on a glass slide and relaxed with gentle heat. Measurements and photographs were taken, and the specimen was transferred to a 0.5-ml Eppendorf tube containing 0.25 M NaOH. Total genomic DNA was prepared by a rapid technique (4). Morphometric data of the male specimen used for DNA study are: body length 867 μm; body width 81 μm; onchiostyle length 44 μm; spicule length 36 μm; distance of anterior cervical papilla (CP)1 from anterior end 39 μm, CP1 to CP2 25 μm, CP2 to CP3 22 μm; posterior precloacal supplement (SP1) to cloacal opening 27 μm, distance SP1 to SP2 32 μm, distance SP2 to SP3 39 μm. The following primers were used in the PCR reaction: species-specific sense primer SIMIREV2 (5′-CACTCGTCGGACTCAAACC-3′) and universal antisense primer UNIVERSAL (5′-CCCGTCGCTACTACCGATT-3′) (1). A single fragment of approximately 452 bp was amplified. The D2 and D3 expansion regions of the large subunit 28S rDNA were amplified using the primer D2A (5′-ACAAGTACCGTGAGGGAAAGTTG-3′) and D3B (5′-TCGGAAGGAACCAGCTACTA-3′ (3). The region was sequenced after purification of PCR products from the gel slice with a Qiagen gel purification kit (Qiagen Inc., Valencia, CA). The obtained sequence was deposited in Genbank (Accession No. DQ832183). The obtained sequence was compared by BLAST in NCBI and the results showed strong similarities with T. similis (Accession No. AM180730). To our knowledge, this is the first report of T. similis associated with a deciduous forest in the Czech Republic. Taking into account the agricultural importance of trichodorids and tobraviruses as plant pathogens, there is a need for a comprehensive survey of these taxa in the Czech Republic. The damage level threshold is in the case of virus vector species equivalent to a single nematode. Therefore, information on these plant parasites would be useful for developing nematode management strategies. References: (1) K. Boutsika et al. Plant Pathol. 53:110, 2004. (2) W. Decraemer and P. Baujard. Fundam. Appl. Nematol. 21:37, 1998. (3) P. De Ley et al. Nematology 2:591, 1999. (4) J. M. Stanton. Australas. Plant Pathol. 27:112, 1998.