bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of Tomato yellow leaf curl virus in China
Authors: Wu J. B. , Dai F. M. , Zhou X. P. 
Published: May 2007

Tomato yellow leaf curl virus (TYLCV) is a devastating pathogen of tomato that causes significant yield losses in many tropical and subtropical regions (2). In China, however, there has as yet been no report of this virus, although other begomoviruses have been reported infecting tomato (1,3). A yellow mosaic disease was observed on tomato with 90% disease incidence during March 2006 in fields of Sunqiao, Shanghai Province, China. Triple-antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) tests indicated that tomato plants were not infected by Tomato mosaic virus or Cucumber mosaic virus. Tomato plants were found to be infested with Bemisia tabaci, suggesting a begomovirus etiology. The disease agent was transmitted to tomato by whiteflies and produced yellow mosaic and stunting symptoms that were identical to those observed in the field. Total DNA was isolated from eight collected leaf samples. Polymerase chain reaction (PCR) was performed with begomovirus degenerate primers PA and PB (3), and an amplicon of the expected size (~500 bp) was obtained in all eight samples but not from healthy leaf samples. The PCR products from two samples (SH1 and SH2) were cloned and sequenced. All residues in the sequences were confirmed by comparison of duplicate clones. Alignment of the sequences showed that they shared 97.4% nucleotide sequence identity (GenBank Accession No. AM282874–75), suggesting that they were infected by an identical virus. Overlapping primers Full/F (5′-AGCCCAATACATTGGGCC ACGA-3′) and Full/R (5′-CGTAAGTTTCCTCAACGGACTGC-3′) were then designed to amplify the full length DNA-A of SH2. The sequence was determined to be 2,781 nucleotides long (GenBank Accession No. AM282874). A comparison with other begomoviruses shows SH2 DNA-A has the highest nucleotide sequence identity (99.8%) with TYLCV isolate Tosa from Japan (GenBank Accession No. AB192966). The above results indicate that the virus associated with yellow mosaic disease of tomato in Shanghai is an isolate of TYLCV. To our knowledge, this is the first report of TYLCV in China and the first report of a begomovirus in Shanghai. References: (1) X. F. Cui et al. J. Virol. 78:13966, 2004. (2) E. Moriones and J. Navas-Castillo. Virus Res. 71:123, 2000. (3) Z. H. Li et al. Arch. Virol. 149:1721, 2004.
First Report of Phytoplasmas in Grapevine in South Africa
Authors: Botti S. , Bertaccini A. 
Published: May 2007

In April 2006, grapevine plants with typical symptoms of yellows (GY) were observed in some South African vineyards. The affected plants showed premature yellowing or reddening and downward rolling of leaves. In some cases, these symptoms were associated with extensive lack of cane lignification that was undistinguishable from yellows symptoms reported in grapevine in the major viticultural areas of the world. Nucleic acids were extracted separately from 0.1 g of fresh leaf midribs and cane phloem scrapes from three symptomatic and three asymptomatic grapevine plants, cv. Shiraz, and from three symptomatic plants, cv. Cabernet, collected from three different locations using Qiagen (Milan, Italy) DNAeasy Plant Mini Kit. A nested polymerase chain reaction (PCR) assay was employed for phytoplasma detection with 2.5 μl of the extracted DNA. Direct and nested PCR assays were performed with P1/P7 (2) and R16F2/R2 (1) universal primer pairs, respectively, obtaining the expected products only from phloem scrapes of the symptomatic plant samples cv. Shiraz. Restriction fragment length polymorphism (RFLP) analyses of R16F2/R2 amplicons with TruI and Tsp509I restriction enzymes, discriminating among phytoplasma ribosomal group and subgroups, showed profiles corresponding to those of “Candidatus Phytoplasma aurantifolia” (ribosomal subgroup 16SrII-B) in all three positive samples. A Stolbur phytoplasma profile (ribosomal subgroup 16SrXII-A) was also observed in one of those samples, indicating the presence of mixed phytoplasma infection (1). Sequencing of the obtained amplicons confirmed the RFLP phytoplasma identification; in particular 16SrXII-A could be the same phytoplasma associated with the ‘Bois Noir’ disease reported in grapevine; the 1601-bp sequence of 16SrII-B phytoplasma showed 98% similarity to U15442, i.e., to the phytoplasma associated with lime witches'-broom disease in Oman (“Ca. P. aurantifolia”) confirming RFLP results. To our knowledge, this is the first report of phytoplasmas in grapevine in South Africa. References: (1) I.-M. Lee et al. Phytopathology 85:728, 1995. (2) B. Schneider et al. Pages 369–380 in: Molecular and Diagnostic Procedures in Mycoplasmology Vol. I. Academic Press Inc., 1995.
First Report of Cucumber mosaic virus Subgroup II Infecting Lycopersicon esculentum in India
Authors: Sudhakar N. , Nagendra-Prasad D. , Mohan N. , Murugesan K. 
Published: May 2007

During a survey in January 2006 near Salem in Tamil Nadu (south India), Cucumber mosaic virus was observed infecting tomatoes with an incidence of more than 70%. Plants exhibiting severe mosaic, leaf puckering, and stunted growth were collected, and the virus was identified using diagnostic hosts, evaluation of physical properties of the virus, compound enzyme-linked immunosorbent assay (ELISA) (ELISA Lab, Washington State University, Prosser), reverse-transcription polymerase chain reaction (RT-PCR), and restriction fragment length polymorphism analysis (DSMZ, S. Winter, Germany). To determine the specific CMV subgroup, total RNA was extracted from 50 infected leaf samples using the RNeasy plant RNA isolation kit (Qiagen, Hilden, Germany) and tested for the presence of the complete CMV coat protein gene using specific primers as described by Rizos et al. (1). A fragment of the coat protein was amplified and subsequently digested with MspI to reveal a pattern of two fragments (336 and 538 bp), indicating CMV subgroup II. No evidence of mixed infection with CMV subgroup I was obtained when CMV isolates representing subgroups I (PV-0419) and II (PV-0420), available at the DSMZ Plant Virus Collection, were used as controls. Only CMV subgroup I has been found to predominantly infect tomato in the Indian subcontinent, although Verma et al. (2) identified CMV subgroup II infecting Pelargonium spp., an ornamental plant. To our knowledge, this is the first report of CMV subgroup II infecting tomato crops in India. References: (1) H. Rizos et al. J. Gen. Virol. 73:2099, 1992. (2) N. Verma et al. J. Biol. Sci. 31:47, 2006.
First Record of Crown and Root Rot Caused by Cylindrocladium pauciramosum on California Lilac in Italy
Authors: Polizzi G. , Vitale A. , Aiello D. , Parlavecchio G. 
Published: May 2007

California lilacs, or Ceanothus, are evergreen, drought tolerant, colorful ornamental shrubs belonging to the Rhamnaceae family. Ceanothus thyrsiflorus var. repens is the most common species grown in Italy. In October 2005, a severe wilting was noticed on approximately 3,000 potted, 6-month-old plants obtained from cuttings produced by a commercial nursery in Lecco Province (northern Italy). Wilting was always associated with root rot and brown discoloration at the base of the stem. No leaf spots or stem lesions were detected. A Cylindrocladium sp. was isolated consistently from crown, basal stems, and roots of symptomatic plants with potato dextrose agar. Although many crown rots are caused by Phytophthora spp., this pathogen was not found associated with rotten roots and crown plating small pieces of diseased root tissue and crowns onto selective medium. A random selection of five Cylindrocladium sp. isolates was obtained from the infected crown and basal stem. Subsequently, they were identified on carnation leaf agar (CLA) as Cylindrocladium pauciramosum C.L. Schoch & Crous on the basis of their obpyriform to broadly ellipsoidal terminal vesicles, conidiophore branching pattern, conidium, and perithecial morphology, as well as mating type with tester strains of C. pauciramosum selected isolates (1,4). All single-conidial isolates were mated with tester strains DISTEF-G87 (MAT1-1) and DISTEF-G128 (MAT1-2) of C. pauciramosum on CLA, which confirmed both mating types to be present. Two of the isolates were deposited at Fungal Biodiversity Centre, Centraalbureau voor Schimmelcultures (CBS-120145 and CBS-120146). Pathogenicity tests were performed by macerating CLA cultures of C. pauciramosum, obtained from a single-spore isolate and incorporating them on the soil surface of 20 8-month-old C. thyrsiflorus var. repens potted plants. The same number of plants was used as the control. Following inoculation, plants were well irrigated and kept in a growth chamber at 25 ± 1°C. All inoculated plants developed crown rot, basal stem rot, and root rot 25 days after inoculation. Uninoculated control plants remained healthy. C. pauciramosum was reisolated from the artificially inoculated plants. C. pauciramosum causes considerable damage to the ornamental industry in Italy, where projects have been carried out since the first record of the fungus in Europe (3). C. pauciramosum was previously detected on Ceanothus sp. in the United Kingdom (2), where foliar and stem lesions were described. To our knowledge, this is the first record of the pathogen on C. thyrsiflorus var. repens and the first report of wilting due to crown and basal stem rot. References: (1) P. W. Crous. Taxonomy and Pathology of Cylindrocladium (Calonectria) and Allied Genera. The American Phytopathological Society, St. Paul MN, 2002. (2) C. R. Lane et al. Plant Pathol. 55:582, 2006. (3) G. Polizzi and P. W. Crous. Eur. J. Plant Pathol. 105, 407, 1999. (4) C. L. Schoch et al. Plant Dis. 85:941, 2001.
First Report of Septoria pistaciae Causing Leaf Spot of Pistachio in Egypt
Authors: Haggag Waffa M. , Abou Rayya M. S. M. , Kasim N. E. 
Published: May 2007

In May 2006, leaf spots were observed on approximately 60% of 8-year-old pistachio (Pistacia vera L.) trees in an orchard located at Rhafah, north of Sinai, Egypt. These spots were typically circular, or occasionally irregular, with white-to-light tan or gray centers and a purple or brown border measuring 1 to 5 mm in diameter, or occasionally larger on the upper leaf surface. A narrow, brown border surrounded the spot, and with age, the lesion cracked. Spots occasionally turned brown and closed to form blotches. Fungal isolates from the leaf spots were identified as Septoria pistaciae on the basis of characteristics of pycnidia and conidia. From the leaf spots, numerous black pycnidia were found that produced hyaline conidia, 3 to 7 septate, generally filiform although tapering at one end, and measuring 46 to 75 × 3 to 4 μm. Pycnidia were dark, separate, globe shaped with an ostiole from which conidia were extruded, and erupted through the surface of infected plant tissue. Conidia were produced on short conidiophores. Single conidial isolations onto 2% malt agar consistently formed slow-growing, dark green colonies. To confirm the pathogenicity of the isolate of S. pistaciae, a suspension of 5 × 105 conidia per ml in water was applied at 1 ml per leaf to 20 leaves of 10 rooted cuttings of pistachio trees in 30-cm pots. Ten controls were misted with water only. All plants were covered with plastic bags for 48 h on a greenhouse bench. Greenhouse temperatures ranged from 15 to 20°C with a 16-h photoperiod. After 6 days, all inoculated plants developed symptoms, and the fungus was reisolated from lesions. No symptoms were observed on control plants. S. pistaciae was previously reported on pistachio in Texas and Arizona (2,3). Reports included mention of its occurrence in the United States (California), Asia (Armenia Republic of Georgia, India, Israel, Kazakhstan, Kirgizstan, Syria, Turkey, Turkmenistan, and Uzbekistan), and Europe (Albania, France, Greece, Italy, and Portugal) (1). To our knowledge, this is the first report of Septoria leaf spots of pistachio in Egypt. References: (1) T. Andrianova and D. Minler. Septoria pistaciae. Page 159 in: IMI Descriptions of Fungi and Bacteria. CAB International, Wallingford, UK. 2004. (2) A. Chitzanidis. Ann. Inst. Phytopathol. Benaki 10:29, 1956. (3) D. J. Young and T. Michailides. Plant Dis. 73:775, 1989.
First Report of Pratylenchus neglectus and P. thornei Infecting Canola and Weeds in Iran
Authors: Fatemy S. , Abootorabi E. , Ebrahimi N. , Aghabeigi F. 
Published: May 2007

Cultivation of canola (Brassica napus L.) is relatively new in Iran. Because nearly 90% of Iran's edible oil is imported, farmers are subsidized and encouraged to grow this crop. Except for the sugar beet cyst nematode, Heterodera schachtii, to which susceptibility of some canola cultivars has been established (1), information on other nematode pests of canola is lacking. During a survey from April—May 2002 and repeated in 2003, soil and root samples of winter canola and weeds were collected at harvest of canola from research stations and farmers' fields in the south, west, and northwest of Tehran Province. Each sample was a composite of 25 roots and 2 kg of soil per hectare, collected from the rhizosphere of canola with a 2.5-cm-diameter soil corer. Samples were put in plastic bags and kept at 5°C until they were processed, within 2 weeks from sampling. Samples were sieved through a 0.840-cm aperture sieveand mixed thoroughly. Nematodes were extracted from subsamples of 5 g of roots and 250 g of soil with a modification of the sugar centrifugal flotation method (2), counted, and identified. Two species of root lesion nematodes, Pratylenchus neglectus and P. thornei, were found. When they were present in the same field, they occurred in the roots of both Regents × Cobra and Orient cultivars. Averages of 28 and 321 P. thornei per gram were found in the roots of cvs. Regents × Cobra and Orient, respectively. Averages of 30, 1,026, 626, and 450 P. neglectus per gram of roots of cvs. Regents × Cobra, Orient, Ocapi, and GLSIO were detected, respectively, in different fields. Heavily infected plants were stunted and had roots with dark lesions, a symptom typical of the attacks by these nematodes. Generally, greater nematode densities were in the roots than in the soil and both nematode species were more abundant in cooler than in warmer areas of the province. Since these nematodes are also severe pests of wheat, which is also grown in the province, they could pose a potential threat to both crops. Weeds that were present in the sampled fields belonged to the botanical families Scrophulariaceae, Gramineae, Euphorbiaceae, Crucifereae, and Compositeae. Between 22 and 1,500 P. thornei and 17 P. neglectus per gram of roots of Crucifereae and 280 P. thornei per gram of roots of Gramineae were found. To our knowledge, this is the first report of lesion nematodes infecting canola plants in Iran. References: (1) S. Fatemy and E. Abootorabi. Nematol. Mediterr. 30:163, 2002. (2) W. R. Jenkins. Plant Dis. Rep. 48:692, 1964.
First Report of Fire Blight on Pyrus elaeagrifolia and Amelanchier sp. in Bulgaria
Authors: Bobev S. G. , Van Vaerenbergh J. , Maes M. 
Published: May 2007

In 2005, a fire blight epidemic occurred for the second time within the last 3 years, and severe damages were observed on pome fruits trees in many regions of Bulgaria. For the first time, we found fire blight on Pyrus elaeagrifolia and Amelanchier sp. grown in a park area (Plovdiv Region), providing evidence of continuing spread of the pathogen in Bulgaria. The symptoms on P. elaeagrifolia were necrotic, immature fruitlets and progressive necrosis toward the adjacent branches, thus forming cankers and leading to death of the plant above the canker. Many Amelanchier sp. shrubs had severely blighted flowers, fruitlets, shoots, and branches and dried, amber ooze droplets on the shoots. All the isolations made from blighted hosts' shoots and cankers on King's medium B (2 to 3 days, 26 to 27°C) yielded whitish, glistening, round bacterial colonies. Infiltration of the suspensions of randomized isolates from both hosts into tobacco leaves resulted in a typical hypersensitive reaction. Subsequently, some strains showed a typical ooze production on immature pear fruits (cv. Conference) and were also successfully reisolated from artificially inoculated quince shoots (1.2 × 109 CFU, cv. Portugalska, three replicates), where typical fire blight symptoms were observed, thereby fulfilling Koch's postulates. No symptoms or bacteria were found within any of the shoots from the same plant species injected with sterile water. The identity of the isolates was confirmed as Erwinia amylovora by an antibody-based slide agglutination test (Neogen_Express; Neogen Europe, Ltd., UK) and PCR test with primers derived from the ams region (1). On the basis of the symptoms, cultural characteristics, and positive results in pathogenicity, serological, and PCR tests, the isolates were considered to be E. amylovora. To our knowledge, this is the first report of fire blight on P. elaeagrifolia and Amelanchier sp. in Bulgaria. Reference: (1) S. Bereswill et al. Appl. Environ. Microbiol. 61:2636, 1995.
First Report of a “Candidatus Phytoplasma australiense”-Related Strain in Lucerne (Medicago sativa) in Australia
Authors: Getachew M. A. , Mitchell A. , Gurr G. M. , Fletcher M. J. , Pilkington L. J. , Nikandrow A. 
Published: May 2007

Australian lucerne yellows (ALuY), a phytoplasma-associated disease, is a major problem in Australia that causes the pasture seed industry millions of dollars in losses annually (3). Samples were collected from lucerne (Medicago sativa L.) plants exhibiting symptoms indicative of ALuY (4) in a seed lucerne paddock (cv CW 5558) at Griffith, southwestern New South Wales (NSW), Australia, in November 2005 and again in January 2006. Samples were kept at 4°C and processed within 36 h of collection. Total DNA was extracted from approximately 0.3 g of leaf midribs and petioles of each plant sample and used as template in a nested PCR assay with phytoplasma universal primer pairs P1/P7 and fU5/m23sr. PCR products resulting from the first amplification were diluted (1:30) with sterile distilled water (SDW) before reamplification with fU5/m23sr. DNA of Australian tomato big bud (TBB) phytoplasma and SDW were used as positive and negative assay controls, respectively. Ten of fifteen plant samples collected in November tested positive for phytoplasma DNA. Restriction digestion profiles of nested PCR amplicons with HpaII endonuclease were the same for all symptomatic plants but differed from the control. Phytoplasma identity was determined by sequencing two nested PCR products that yielded identical sequences. One was deposited in the GenBank database (Accession No. DQ786394). BLAST analysis of the latter sequence revealed a >99.6% similarity with “Candidatus Phytoplasma australiense” (L76865) and related strains papaya dieback (Y10095), phormium yellow leaf (U43570), strawberry green petal (AJ243044), and strawberry lethal yellows (AJ243045). Direct PCR with primers FP 5′-GCATGTCGCGGTGAATAC-3′ and RY 5′-TGAGCTATAGGCCCTTAATC-3′ designed to specifically amplify DNA of “Ca. P. australiense” detected the phytoplasma in 8 of 40 samples collected in January. Whether this phytoplasma is the etiological agent solely responsible for ALuY is currently under investigation. “Ca. P. asteris” and stolbur group (16SrXII) phytoplasmas have been reported in lucerne in the United States (2) and Italy (1), respectively. Within the stolbur group 16SrXII, “Ca. P. australiense” and stolbur phytoplasma are regarded as separate species and both are distinct from “Ca. P. asteris”, a group 16SrI strain. To our knowledge, this is the first report of a “Ca. P. australiense” related strain in lucerne. References: (1) C. Marzachi et al. J. Plant Pathol. 82:201, 2000. (2) R. D. Peters et al. Plant Dis. 83:488, 1999. (3) L. J. Pilkington et al. Australas. Plant Pathol. 28:253, 1999. (4) L. J. Pilkington et al. First report of a phytoplasma associated with ‘Australian lucerne yellows’ disease. New Disease Report. Online publication at http://www.bspp.org.uk/ndr/jan2002/2001-46.asp .
First Report of Soybean Rust Caused by Phakopsora pachyrhizi on Phaseolus spp. in Argentina
Authors: Ivancovich A. J. , Botta G. , Rivadaneira M. , Saieg E. , Erazzú L. , Guillin E. 
Published: May 2007

Asian soybean rust (ASR), caused by Phakopsora pachyrhizi Syd. & P. Syd., has been reported in Argentina on soybean (Glycine max) and kudzu (Pueraria lobata and Pueraria javanica) since the 2002 growing season (1–4). On 29 May 2006, plants of Phaseolus spp. were found to have tan ASR-like rust lesions on leaves at eight different field plots located in the northwestern province of Salta, Argentina. Growth stages of infected bean plants within plots were between pod setting and physiological maturity. Diagnosis of ASR on bean leaves was performed with a stereoscopic microscope to view rust pustules, and suspected uredinia of P. pachyrhizi were observed, furthermore, typical ASR urediniospores also were also observed at ×400. ELISA and PCR methods gave positive results for ASR. Rust spores from these plants were used to inoculate soybean plants at the V3 growth stage with rust spores from field bean plants produced under greenhouse conditions. Typical ASR tan pustules developed within 21 days of inoculation. Bean rust caused by Uromyces phaseoli also was seen in some of the bean plots but was easily differentiated from ASR because the uredinia were much darker and affected the upper leaves, while the ASR uredinia were lighter and spread from the lower leaves to the upper leaves. This finding is of significance in Argentina because bean is an important crop grown in the northwestern region of the country and is planted approximately 2 months after soybean planting. Given this planting time difference, bean may provide an overwintering host for the survival of ASR spores, thereby providing a green bridge for infection of soybean plants during the following growing season. References: (1) A. J. Ivancovich. Soybean rust situation in Argentina. Oral presentation. Symposium: Soybean Rust: Too Close for Comfort. Annual Meeting of the American Phytopathological Society. 2003. (2) A. J. Ivancovich. Plant Dis. 89:667, 2005. (3) A. J. Ivancovich and G. Botta. Rev. Tecnología Agropecuaria 7(21):16, 2002. (4) A. J. Ivancovich et al. Phytopathology (Abstr.) 94(suppl.):S44, 2004.