bluuebunny/crossref_metadata_2025_split huggingface dataset:
Foliar and Cane Rot of Arundo donax Caused by Nigrospora oryzae in Europe
Authors: Widmer T. , Kirk A. , Kirk G. , Guermache F. 
Published: May 2007

A fungus was isolated consistently from dead shoot tips and flag leaves of Arundo donax L. (Poaceae) in France, Crete, Cyprus, Italy, Morocco, and Spain from April of 2003 through September of 2005. The fungus was identified as Nigrospora oryzae (Berk. & Br.) Petch (teleomorph Khuskia oryzae) on the basis of morphological characteristics (1). The mean diameter of 80 conidia obtained from sporulating plant specimens collected in France, Crete, and Cyprus were 14, 15, and 15 μm, respectively. The mean diameters of 25 conidiogenous cells and conidiophores were 7 and 4 μm, respectively. Identification was confirmed by comparing the sequence of the ribosomal DNA internal transcribed spacer 1 and 4 regions from the French isolate (GenBank Accession No. DQ219433) with the sequence of a voucher specimen from the Museum National d'Histoire Naturelle, Paris, France. The isolate of N. oryzae from France was deposited at the CBS collection in Utrecht, the Netherlands (CBS 113884). N. oryzae is known to be a weak pathogen on a wide range of plants but has not been reported on A. donax, which is now a well-established weed in the United States and North America, probably originating from the Mediterranean Region. Herein, the possible use of N. oryzae as a biological control agent was investigated. Twenty young A. donax shoots growing in the greenhouse and 20 emerging canes in the field were selected on the basis of uniformity in size. A spore suspension in distilled water adjusted to 5 × 105 conidia/ml of the French isolate was prepared and 0.5 ml was injected with a syringe just below the growing point of the flag leaf in onehalf of the greenhouse and field plants. The remaining plants were injected with 0.5 ml of distilled water as controls. Infection and death of the flag leaf occurred in 30% of the shoots in the greenhouse and 50% of the canes in the field 21 days from inoculation. No disease developed on the control plants. Greenhouse inoculation tests were repeated once. N. oryzae was reisolated from dead leaves and the terminal node of inoculated shoots, satisfying Koch's postulate. Attempts made to induce disease symptoms by applying spore suspensions on the whorl of leaves surrounding the apical tip failed. This is an indication that an insect vector may be needed to carry and deposit N. oryzae spores into the tight, whorled flag leaf for infection and disease development to occur. To our knowledge, this is the first report of foliar and cane rot of A. donax caused by N. oryzae. References: (1) K. H. Domsch et al. Page 515 in: Compendium of Soil Fungi. IHW-Verlag, Eching, Germany, 1993.
First Record of Verticillium dahliae on Potato in Malta
Authors: Pace-Lupi T. G. , Porta-Puglia A. , Ippolito A. , Nigro F. 
Published: May 2007

Potato is an important and highly valued crop throughout the Maltese Archipelago. Much of the production is exported to Holland. In January 2005, minor wilts and chlorosis of potato plants were observed in a field at Hal-Farrug, Luqa (Malta). Verticillium dahliae Kleb (1) was isolated on potato dextrose agar (PDA) from vascular tissue excised from the base of the plants. Three different isolates were obtained, all of which were typically distinguished by verticillately shaped conidiophores and the abundant production of microsclerotia on PDA. In May 2005, colonies of these three isolates were cultured in potato dextrose broth (PDB), from which conidial suspensions of each isolate were prepared with sterile distilled water to a concentration of 107 ml-1. For each isolate, 10 7-day-old potato seedlings were inoculated via root immersion in the inoculum suspension and transplanted to 20-cm diameter plastic pots containing a soil/peat mixture (1:1 [v/v]). Seedlings treated in the same way with sterile distilled water were used as a control. All plants were kept under controlled glasshouse conditions (20 ± 3°C) and watered to field capacity as required. Minor chlorosis and wilt of the pair of lower-most leaves was noted 7 days after inoculation. During subsequent weeks, wilt began to appear in the typical half-leaf form, while chlorosis was noted on all organs of the plants, including the principal stem (3). Symptoms were absent on the control plants. Measuring the weight of the new tubers produced by each plant revealed no apparent difference between inoculated and healthy plants; nevertheless, inoculated plants resulted in more tubers with a smaller diameter in respect to those of the uninoculated plants. V. dahliae was never isolated from tubers. Little to no variation in symptom severity was noted among plants inoculated with the three individual isolates. At the end of June, V. dahliae was reisolated on PDA from all inoculated plants, in particular, from vascular tissues originating from principal and lateral stems, crowns, and roots. All attempts to isolate the pathogen from control plants were unsuccessful. Molecular detection of the pathogen by using species-specific primers and real-time Scorpion PCR (2) confirmed the results obtained by the classical isolation method. The low symptom severity observed by the growers in the field, usually mistaken for normal dieback of aged plants, might explain why V. dahliae was never reported before on potatoes in the Maltese Archipelago. References: (1) D. L. Hawksworth and P. W. Talboys. No. 256. Descriptions of Pathogenic Fungi and Bacteria. Commonwealth Mycological Institute (CMI), Kew, Surrey, UK, 1970. (2) F. Nigro et al. Pages 454–461 in: Proc. Convegno Internazionale di Olivicoltura. VI Giornate Scientifiche SOI, Spoleto, 2002. (3) W. R. Stevenson et al., eds. Compendium of Potato Diseases. 2nd ed. The American Phytopathological Society, St Paul, MN, 2001.
Plum Pox Virus Mixed Infection Detected on Apricot in Pakistan
Authors: Kollerová E. , Nováková S. , Šubr Z. , Glasa M. 
Published: May 2007

Sharka, caused by Plum pox virus (PPV), is the most detrimental viral disease of stone fruit trees. First reported from Bulgaria in 1917, the virus is now widespread in Europe, the Mediterranean Basin, and Asia Minor and is sporadically present in North and South America. On the basis of molecular and serological properties, six PPV subgroups are recognized, from which PPV-D, PPV-M, and PPV-Rec are the most common (1,2). Several apricot trees (Prunus armeniaca) showing mild, pale green rings and diffuse chlorotic spots on leaves were found in a small orchard in the Baltistan District in northern Pakistan at approximately 2,400 m above sea level. Dried leaf samples from one symptomatic tree randomly selected from the orchard were positive for PPV using double-antibody sandwich enzyme-linked immunosorbent assay with antisera prepared in the laboratory, immunoblot analysis, and reverse transcription-polymerase chain reaction (RT-PCR) targeting the capsid protein (CP) gene using standard procedures (1). To check the subgroup affiliation and evaluate the molecular variability, the 562-bp variable region spanning the C-terminus of NIb and the N-terminus of the CP was amplified, the RT-PCR product was cloned into the pGEM-T Easy vector (Promega, Madison, WI), and positive clones were analyzed by restriction and sequence analyses. Interestingly, sequence analysis of four clones revealed mixed infection, i.e., the presence of two different PPV isolates in the apricot sample. One isolate belonged to PPV-D (GenBank Accession No. DQ422147) and the other belonged to the PPV-Rec subgroup (GenBank Accession No. DQ422148). Multiple alignment of the sequenced genome portion of the Pakistan PPV-D isolate indicated 96 to 99% nt identity with various PPV-D isolates without unique, clear-cut differences. Similarly, the PPV-Rec isolate had 98 to 99% identity with European PPV-Rec isolates and retained the cross-over at nucleotide position 8450 in the 3′ terminus of NIb. This sequence had the amino acid signature at the N-terminus of the CP typical of the PPV-Rec subgroup (2). Moreover, no particular clustering of the Pakistan isolates within PPV-D and PPV-Rec could be observed after phylogenetic analysis. The DAG motif, essential for aphid transmission, was present in both sequences. To our knowledge, this is the first indication of PPV occurrence in Pakistan and first identification of the PPV-Rec isolate outside Europe. Together with previous reports on the PPV presence in China and Kazakhstan (3,4), this report indicates the need for more detailed epidemiological studies focusing the PPV spread and its molecular diversity in Asia. References: (1) T. Candresse et al. Phytopathology 88:198, 1998. (2) M. Glasa et al. J. Gen. Virol. 85:2671, 2004. (3) M. Navrátil et al. Plant Dis. 89:338, 2005. (4) S. Spiegel et al. Plant Dis. 88:973, 2004.
First Report of Ravenelia spegazziniana on Acacia farnesiana from Brazil
Authors: Avanzato M. V. , da Silveira R. M. Borges , Hernández J. R. 
Published: May 2007

Leaves, young branches, and fruits of Acacia farnesiana (L.) Willd. (Fabaceae) that were distorted because of hypertrophy causing witches' brooms and other abnormal growth were collected in the area surrounding the Panteón da Liberdade e da Democracia, Brasilia, Brazil, during August 2005. Uredinia and telia were observed in the symptomatic areas. The uredinia were small on leaflets and rachis and on pods in confluent groups as much as 1 cm in diameter, subcuticular becoming erumpent, and cinnamon-brown; paraphyses were mostly clavate and colorless. Urediniospores were 17 to 28 × 12 to 16 μm, ellipsoid to obovoid, with a wall 1.5 to 2 μm thick at the sides and 2 to 3 μm at the apex, cinnamon-brown, with hub and spoke pattern of ornamentation, and pores in two bands of four each above and below the equator. Telia were small, erumpent, on rachis and small branches, and dark cinnamon-brown. Teliospores were 84 to 100 × 65 to 90 μm in diameter, chestnut-brown, (4) 5 to 6 probasidial cells across, and smooth; cysts were globoid, same number as peripheral probasidial cells; pedicels were colorless, multihyphal, and deciduous. The rust was identified as Ravenelia spegazziniana J.C. Lindq, on the basis of the comparison with specimens deposited at the Instituto Spegazzini (LPS) and U.S. National Fungus Collection (BPI), as well as with published descriptions (2). R. spegazziniana has been reported on species of Acacia from Central, North, and South America, and Hawaii (1). A. farnesiana is probably native to tropical America, but it is naturalized and cultivated all over the world where it has become invasive in disturbed areas in some Pacific islands. This species is economically important for fuel wood, flowers used in the perfume industry, and bark and fruits used for tannin production. In Federal District (DF), Brasilia, Brazil, A. farnesiana is commonly used in urban forestation as an ornamental and shade tree. To our knowledge, this is the first report of R. spegazziniana in Brazil. The voucher specimen has been deposited in the herbarium of the Faculty of Biology of Porto Alegre from the Universidade Federal do Rio Grande do Sul as ICN 139085. References: (1) D. F. Farr et al. Fungal Databases. Systematic Botany and Mycology Laboratory. On-line publication. ARS, USDA, 2006. (2) J. R. Hernandez and J. F. Hennen. Mycol. Res. 106:972. 2002.
A New Natural Host of Lisianthus necrosis virus in Taiwan
Authors: Chen Y. K. , Jan F. J. , Chen C. C. , Hsu H. T. 
Published: May 2007

Lisianthus necrosis virus (LNV) was first identified as a fungus-borne virus that induced systemic necrosis in lisianthus (Eustoma russellianum) in Japan (2). In Taiwan, LNV causes systemic bright yellow chlorosis followed by necrosis in lisianthus (1). The disease was able to spread through the infested soil. Isolation of a fungus vector was attempted but was not successful (1). Calla lilies (Zantedeschia spp.) showing symptoms of systemic necrosis were observed in the fields of central Taiwan. A virus culture was established through single-lesion isolation from a local lesion host, Chenopodium quinoa, and maintained in Nicotiana benthamiana. Mechanical inoculation of the virus resulted in systemic infection in E. russellianum and Datura stramonium and local infection in Celosia argentea, Gomphrena globosa, Chenopodium amaranticolor, Zinnia elegans, Cucumis melo, Cucumis sativus, Cucurbita pepo, Vigna angularis, and Petunia hybrida. Electron microscopic examination of ultrathin sections of infected plant tissues revealed the presence of spherical viral particles approximately 33 nm in diameter. Scattered and aggregated virion particles were frequently observed in the cytoplasm of infected cells. Results of enzyme-linked immunosorbent assay, western blotting, and immunoelectron microscopy indicate that the virus is serologically related to LNV (1). Reverse transcription-polymerase chain reaction (RT-PCR) with degenerate primers (forward primer 5′-ATGGAAATCGTTAGG and reverse primer 5′-CTATAGCAATGTTGC) for LNV coat protein gene produced a cDNA of approximately 1.1 kb. The RT-PCR product was cloned into pGEM-T vector (Promega, Madison, WI) and sequenced. Sequence analysis showed that the cloned fragment (GenBank Accession No. DQ523229) was 1,167 bp long and shared 99% identity at the nucleotide and deduced amino acid levels with that of the LNV isolated from lisianthus (GenBank Accession No. DQ011234). To our knowledge, this is the first report of the natural occurrence of LNV infection in calla lily. References: (1) C. C. Chen et al. Plant Dis. 84:506, 2000. (2) M. Iwaki et al. Phytopathology 77:867, 1987.
Natural Infection of Verbena and Phlox by a Recently Described Member of the Carmovirus Genus
Authors: Assis Filho F. M. , Harness A. , Tiffany M. , Gera A. , Spiegel S. , Adkins S. 
Published: May 2007

A novel carmovirus infecting angelonia (Angelonia angustifolia) was recently described independently by researchers in the United States, Israel, and Germany (1,2,4). Angelonia flower break virus (AnFBV) and Angelonia flower mottle virus were proposed as appropriate names for this carmovirus. The virus, causing stunting, mild leaf mottle, flower mottling, and flower breaking symptoms has been detected in naturally infected angelonia in the United States, Israel, and Germany (2,4). Here we report the first detection of natural infection of verbena (in the United States and Israel) and phlox (in the United States) by using a recently developed double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA; Agdia, Elkhart, IN). Prior to this report, verbena was considered insusceptible to carmovirus infection (3) and phlox was known as an experimental host for AnFBV (2). A comparative serological study including 27 virus species, demonstrated that DAS-ELISA did not cross-react with any viruses that commonly infect ornamentals or are related to carmoviruses, showing that the polyclonal antibodies are specific to AnFBV. Antibody specificity was confirmed by the carmovirus group PCR test (Agdia). Furthermore, reverse transcription-polymerase chain reaction with AnFBV specific primers (2) produced the expected 1172-bp band from all ELISA-positive samples tested. Between November 2005 and March 2006, AnFBV was detected in 181 of 567 verbena, 26 of 143 phlox, and 193 of 267 angelonia samples submitted to Agdia Testing Services by commercial ornamental propagators for virus testing. Most samples were asymptomatic, although a few exhibited mild leaf mottle. It should be noted that the number of AnFBV-infected samples might not accurately reflect the actual number of commercially produced plants infected with AnFBV because most of the samples analyzed originated from virus elimination programs. The detection of natural AnFBV infection of verbena, phlox, and angelonia suggests that AnFBV may be more widespread in the ornamental industry than previously thought. References: (1) S. Adkins et al. Phytopathology (Abstr.) 95(suppl.):S2, 2005. (2) S. Adkins et al. Phytopathology 96:460, 2006. (3) G. P. Martelli and M. Russo. Online publication. ICTVdB-The Universal Virus Database. 00.074.0.02, 2004. (4) S. Winter et al. New Disease Reports. Vol 12. Brit. Soc. Plant Pathol. Online publication, 2005.
First Report of the Purple Variant of Curtobacterium flaccumfaciens pv. flaccumfaciens, Causal Agent of Bacterial Wilt of Bean, in Canada
Authors: Huang H. C. , Erickson R. S. , Yanke L. J. , Chelle C. D. , Mündel H.-H. 
Published: May 2007

Bacterial wilt of bean (Phaseolus vulgaris L.) caused by the yellow and orange variants of Curtobacterium flaccumfaciens pv. Flaccumfaciens (Hedges) Collins & Jones was found in western Canada in 2002 (1). A purple variant was found in a pooled sample of discolored cull seeds of great northern bean (cv. US1140) from a crop grown near Bow Island, Alberta, Canada in 2005. Bacterial colonies isolated from purple seed using modified Burkholder's agar (MBA) (3) were convex, glistening, and smooth edged with blue pigment diffusing into the medium. Three isolates (V154, V155, and V254) were identified with conventional tests (2), carbohydrate oxidation (GP Microplates, Biolog Inc., Hayward, CA), and cellular fatty acids (CFA) (MIDI, Inc., Newark, DE). All were grampositive, motile, aerobic rods with yellow colonies producing extracellular blue pigment on MBA when grown at 20 ± 2°C. Bacterial isolates grew at 27°C but grew weakly at 37°C. They were positive for catalase and hydrolysis of hippurate and indoxyl acetate and negative for urease, gelatin liquification, and oxidase. CFA profiles were approximately 48% 15:0 anteiso, 40% 17:0 anteiso, 7% 16:0 iso, and 3% 15:0 iso; with 17:1 anteiso A variable but <1%. Many carbohydrates were oxidized in the Biolog microplates with little acid production. The results match C. flaccumfaciens (2) and the MIDI and Biolog databases, as well as the purple variant of C. flaccumfaciens found in Nebraska, the only previous report of this variant (4). The pathogenicity of the three isolates was tested. Seeds of great northern (cv. US1140) and navy (cv. Morden003) beans were soaked in a bacterial suspension (1 × 108 CFU/ml) or distilled water (control) for 1 h, planted in Cornell mix in root trainers, incubated at 28/22°C (16-h day/8-h night) in a growth cabinet for 14 days, and examined for seedling wilt. The test had three replicates per treatment and 20 seeds per replicate in a completely randomized design. All three isolates were pathogenic to both bean cultivars. The wilt incidences were 51, 57, and 56% on US1140 and 64, 76, and 69% on Morden003 for isolates V154, V155, and V254, respectively. The purple variant of C. flaccumfaciens was reisolated from hypocotyls of wilted seedlings but not from healthy controls. The experiment was repeated using the reisolated bacteria and the results were similar to the first experiment, thus fulfilling Koch's postulates. To our knowledge, this is the first report of the purple variant of C. flaccumfaciens pv. flaccumfaciens in Canada. References: (1) T. F. Hsieh et al. Plant Dis. 86:1275, 2002. (2) K. Komagata et al. Page 1313 in: Bergey's Manual of Systematic Bacteriology. Vol. 2. Williams and Wilkens, Baltimore, MD, 1986. (3) G. A. Nelson and G. Semeniuk. Phytopathology 54:330, 1964. (4) M. L. Schuster et al. Can. J. Microbiol. 14:423, 1968.
First Report of Potato virus M and Chrysanthemum stunt viroid in Solanum jasminoides
Authors: Verhoeven J. Th. J. , Jansen C. C. C. , Roenhorst J. W. 
Published: May 2007

In 2005, a plant of the ornamental crop Solanum jasminoides from the Netherlands was submitted for testing on viruses and viroids because of its intended use for propagation. Sap from this plant was mechanically inoculated to the test plant species Chenopodium quinoa, Nicotiana benthamiana, N. hesperis-67A, and N. occidentalis-P1 (3). N. hesperis-67A showed chlorotic local lesions and rugosity followed by vein necrosis, N. occidentalis-P1 showed necrotic local lesions and systemic leaf distortion, and the two other test plant species remained symptomless. Potato virus M (PVM) was identified by double antibody sandwich enzyme-linked immunosorbent assay using leaves from S. jasminoides and N. hesperis-67A. The plant of S. jasminoides was also tested for the presence of viroids by reverse transcriptase-polymerase chain reaction (RT-PCR) with universal pospiviroid primers Pospi1-RE/FW (2). This reaction yielded an amplicon of the expected size of 198 bp. The sequence showed 100% identity to an isolate of Chrysanthemum stunt viroid (CSVd; NCBI GenBank Accession No. AF394453). Subsequently, the complete sequence of our viroid isolate (GenBank Accession No. DQ406591) was determined from the amplicon obtained after RT-PCR using specific primers for the detection of CSVd (1). The viroid isolate from S. jasminoides consisted of 354 nucleotides and showed the highest identity (98.6%) to a chrysanthemum isolate of CSVd (GenBank Accession No. AB055974). Therefore, the viroid was identified as CSVd. To our knowledge, this is the first report of PVM and CSVd in S. jasminoides. Reference: (1) R. Hooftman et al. Acta Hortic. 432:120, 1996. (2) J. Th. J. Verhoeven et al. Eur. J. Plant Pathol. 110:823, 2004. (3) J. Th. J. Verhoeven and J. W. Roenhorst, EPPO Bull. 33:305, 2003.
Introduction of the Exotic Monopartite Tomato yellow leaf curl virus into West Coast Mexico
Authors: Brown J. K. , Idris A. M. 
Published: May 2007

Leaf curl symptoms that are reminiscent of begomovirus (genus Begomovirus, family Geminiviridae) infection were observed widespread in the tomato crop during the early fall 2005 through the spring 2006 growing seasons in Sinaloa State, Mexico. Symptoms were widespread in three major valleys (Culiacan, Guasave, and Los Mochis) that are largely dedicated to fresh-market tomato production for the U.S. market from October to June. Symptoms included stunting of leaves, shortened internodes, distortion of leaf margins, and green vein banding. Fruit set was reduced significantly (as much as 90%) on the portion of the plant that developed above the point of symptom expression. Tomato fields were heavily infested with the B biotype of the whitefly Bemisia tabaci (Genn.) vector and no other insect vectors were noted in the fields. Total DNA was extracted from six symptomatic tomato plants (two from each valley) and used as template to amplify, clone, and sequence the core region of the begomovirus CP. BLAST analysis of begomovirus sequences available in the NCBI GenBank database indicated the closest match was the Old World monopartite begomovirus Tomato yellow leaf curl virus (TYLCV) from Israel (Accession No. X15656) at 97.8% shared nucleotide (nt) identity. The full-length genome was amplified for each of six isolates using TempliPhi (Amersham Biosciences, Piscataway, NJ) and cloned into the pGEM7 vector (Promega, Madison, WI). The complete DNA genome sequence was determined for eight clones by primer walking. Cloned TempliPhi products sequenced represented two to three isolates from each valley. Results indicated that the isolates (n = 8) were 98.9 to 100% identical (Accession No. DQ631892) to each other, and they shared 98% identity with TYLCV isolates reported from the Caribbean Region and Florida. This highly virulent begomovirus of tomato, originating in Israel, was first reported in Mexico from 1996 to 1997 when it was identified in tomato plants in the Yucatan Peninsula (1) (>1,500 miles from Sinaloa). The latter report followed the introduction of TYLCV in tomato seedlings from Florida into several eastern U.S. states (3,4) and then into Puerto Rico (2). The introduction of TYLCV into Sinaloa where tomato production is highly concentrated is significant because the region supplies the majority (as much as 93%) of fresh-market tomatoes to the western United States from October to June (>$750 million dollars). Of equal importance is the immediate proximity of the pandemic to California where more than 90% of the processing tomatoes in the United States are grown. References: (1) J. T. Ascencio-Ibáñez et al. Plant Dis. 83:1178, 1999. (2) J. Bird et al. Plant Dis. 85:1028, 2001. (3) M. T. Momol et al. Plant Dis 83:487, 1999. (4) J. E. Polston and P. K. Anderson, Plant Dis. 81:1358, 1997.