bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of Tomato yellow leaf curl virus Infecting Common Bean (Phaseolus vulgaris) in Greece
Authors: Papayiannis L. C. , Paraskevopoulos A. , Katis N. I. 
Published: May 2007

Tomato yellow leaf curl is one of the most devastating virus diseases of tomato (Lycopersicon esculentum Mill) crops worldwide. Several whitefly-transmitted viruses are associated with the disease and all are assigned to the genus Begomovirus, family Geminiviridae. In Greece, Tomato yellow leaf curl virus (TYLCV) was first reported to infect greenhouse and open-field tomatoes in 2000 (2). During 2006, a survey was conducted in the southwestern part of Peloponnese (mainland) within the areas of Kyparissia and Filiatra (Perfecture of Messinia) to identify the prevalence and natural hosts of the disease. During this survey, yellow mosaic, severe leaf curling, and leaf crumple symptoms were observed in greenhouse bean plants (Phaseolus vulgaris) that were cultivated together with tomatoes showing typical TYLCV symptoms. In all affected greenhouses, the incidence of the disease ranged from 1 to 5% in beans and 90 to 100% in tomato plants. Both bean and tomato plants were highly infested with Bemisia tabaci (Gennadius) populations and produced unmarketable fruits. Twenty-four symptomatic bean plants were collected from four greenhouses that tested positive by triple-antibody sandwich-ELISA using TYLCV-specific antibodies purchased from NEOGEN, EUROPE, Ltd. DNA was extracted from all infected bean plants, and a 580-bp fragment of the coat protein gene was amplified by PCR using the TY(+)/TY(-) primer pair (1). Amplified fragments were then analyzed by restriction fragment length polymorphism with Ava II cutter enzyme. Two DNA fragments of 277 and 302 bp in agarose gels were produced from all isolates and the restriction pattern corresponded to TYLCV. The amplified DNA from four infected bean plants was cloned and sequenced. All four sequences were 100% identical (EMBL Accession No. AM418398) and showed 99% nucleotide identity to a TYLCV isolate from Italy (EMBL Accession No. DQ144621). To our knowledge, this is the first report of TYLCV infection of P. vulgaris, which is an important commercial crop in Messinia, Greece. Within the last decade, TYLCV has emerged as an important pathogen for several cultivated plants in many regions and different TYLCV variants have been reported to infect P. vulgaris (3). Bean is often used as an intercrop between tomato crops, and thus, infected plants may serve as a potential reservoir for virus survival and spread (4). References: (1) G. P. Accotto et al. Eur. J. Plant Pathol. 106:179, 2000. (2) A. D. Avgelis et al. Plant Dis. 85:678, 2001. (3) J. Morris et al. EPPO Bull. 32:41, 2002. (4) J. Navas-Castillo et al. Plant Dis. 83:29, 1999.
Transmission of ‘Candidatus Phytoplasma aurantifolia’ to Bakraee (Citrus reticulata Hybrid) by Feral Hishimonus phycitis Leafhoppers in Iran
Authors: Salehi M. , Izadpanah K. , Siampour M. , Bagheri A. , Faghihi S. M. 
Published: May 2007

Witches'-broom disease of lime (WBDL) caused by ‘Candidatus Phytoplasma aurantifolia’ is a devastating disease in the Sultanate of Oman, United Arab Emirates, and southern Iran. The disease primarily affects lime (Citrus aurantifolia), but in Iran, it is also found in bakraee, a natural C. reticulata hybrid. The disease has been experimentally transmitted from lime to several citrus cultivars by grafting and to a number of herbaceous hosts by dodder. However, the natural vector of ‘Ca. P. aurantifolia’ has not been determined. The most common phloem-feeding insect associated with lime trees in the area is the leafhopper Hishimonus phycitis. The WBDL phytoplasma has been detected in the body of this leafhopper by ELISA and PCR (1), but previous attempts to establish its vector status have failed. It was recently reported that the leafhopper can release the phytoplasma into a sugar solution by feeding through a Parafilm membrane (4). Here we report successful transmission of WBDL phytoplasma to bakraee seedlings by H. phycitis. The leafhopper nymphs and adults were collected in a WBDL-infected lime orchard in Minab (Hormozgan Province) in May of 2006. Of more than 100 leafhopper samples tested, at least 70% were positive for the phytoplasma by PCR using P1/P7 primer pair (3). Additional field-collected leafhoppers were caged (five per plant) on bakraee seedlings at the two-leaf stage in pots in the greenhouse in Zarghan (Fars Province). After 8 weeks, the remaining leafhoppers were killed with an insecticide. Six months after inoculation, 3 of 10 inoculated plants showed typical symptoms of WBDL, including bud proliferation, general chlorosis, and stunting. Symptomatic plants were strongly positive in PCR assays using primer pair P1/P7. No amplification was obtained with healthy control lime or nonsymptomatic bakraee seedlings. Amplified P1/P7 primed PCR products (1,800 bp) from experimentally vector-challenged bakraee seedlings, captured H. phycitis, and a naturally infected lime tree from Minab were subjected to restriction fragment length polymorphism (RFLP) analysis using AluI, HhaI, HpaII, RsaI, and TaqI enzymes. RFLP patterns from these sources were identical and similar to those reported earlier (2). These analyses verified the identity of WBDL phytoplasma in experimentally infected bakraee seedlings. To our knowledge, this is the first report of natural transmission of ‘Ca. P. aurantifolia’ by H. phycitis. References: (1) J. M. Bové et al. Proc. Conf. IOCV 12:342. 1993. (2) A. J. Khan et al. Phytopathology 92:1038, 2002. (3) B. Schneider et al. Pages 369–380 in: Molecular and Diagnostic Procedures in Mycoplasmology. Vol. 2. S. Razin and J. G. Tully, eds. Academic Press, New York, 1995. (4) M. Siampour et al. Iran. J. Plant Pathol. 41:139 (Farsi) and 35 (English), 2006.
First Report of Alternaria dianthicola Causing Leaf Blight on Withania somnifera from India
Authors: Maiti C. K. , Sen S. , Paul A. K. , Acharya K. 
Published: May 2007

Withania somnifera (L.) Dunal, a potential medicinal plant used for the treatment of nervous disorders, intestinal infection, leprosy, and cancer, is a perennial herb belonging to Solanaceae and distributed throughout the drier parts of India. Leaf blight disease of this plant generally occurs during March in various districts of South Bengal, India. At the initial stage of infection, symptoms appear as small, light brown spots, gradually becoming irregular, dark brown, concentrically zonate with a diffuse margin, frequently surrounded by light yellow haloes, conspicuous brownish concentric rings in the advance stage of infection. A species of Alternaria was isolated from the lesions. The pathogen was isolated on potato dextrose agar (PDA) media. On PDA, the fungus grew slowly with colonies reaching approximately 35 to 40 mm in diameter in 7 days when incubated at 30°C. Conidiophores arose singly or in groups, straight or flexous, cylindrical, septate, pale to olivaceous brown, as much as 155 μm long, 4 to 5.5 μm thick; conidia were straight, obclavate, pale olivaceous brown, smooth, with up to 15 transverse and rarely 1 or 2 longitudinal or oblique septa and measured 50 to 115 × 5 to 10 μm. Pathogenicity tests were carried out three times on 6-month-old plants (n = 10). Plants were sprayed with a conidial suspension of 105 conidia/ml; control plants were sprayed with sterilized water. Plants were covered with polyethylene bags for 10 days. Disease symptoms appeared after 12 ± 1 day after inoculation. Symptoms on the leaves were similar to those of a naturally occurring diseased plant. The fungal pathogen was consistently reisolated from inoculated plants. The pathogen was identified as Alternaria dianthicola and further confirmed by the Agharkar Research Institute, Pune, India. A literature survey reports the occurrence of some fungal diseases (1), but to our knowledge, this is the first report of A. dianthicola on W. somnifera. References: (1) P. Sinha et al. Page 14 in: Recent Progress in Medicinal Plants. Vol. 6 Diseases and their Management. Sci Tech Publishing LLC, Houston, TX, 2000.
First Report of Iris yellow spot virus on Onion and Leek in Western Oregon
Authors: Gent D. H. , Martin R. R. , Ocamb C. M. 
Published: May 2007

Onion (Allium cepa) and leek (Allium porrum) are grown on approximately 600 ha in western Oregon annually for bulb and seed production. During July and August of 2006, surveys of onion bulb crops and onion and leek seed crops in western Oregon found plants with symptoms of elongated to diamond-shaped, straw-colored lesions characteristic of those caused by Iris yellow spot virus (IYSV) (1–4). Symptomatic plants were collected from fields of an onion bulb crop, an onion seed crop, and two leek seed crops located in Marion County. The onion bulb crop had been planted in the spring of 2006, and the onion and leek seed crops had been planted in the fall of 2005, all direct seeded. Cultivar names were not provided for proprietary purposes. Symptomatic plants in the onion bulb crop and leek seed crop generally were found near the borders of the field. Disease incidence was less than 5% and yield losses in these crops appeared to be negligible. In the onion seed crop, symptomatic plants were found throughout the field and disease incidence was approximately 20%. Approximately 1% of the onion plants in this field had large necrotic lesions that caused the seed stalks (scapes) to lodge. The presence of IYSV was confirmed from symptomatic leaves and scapes by ELISA (Agdia Inc., Elkhart, IN) using antiserum specific to IYSV. RNA was extracted from symptomatic areas of onion leaves and scapes, and a portion of the nucleocapsid gene was amplified by reverse transcription-PCR. The amplicons were sequenced and found to share more than 99% nucleotide and amino acid sequence identity with an onion isolate of IYSV from the Imperial Valley of California (GenBank Accession No. DQ233475). In the Pacific Northwest region of the United States, IYSV has been confirmed in the semi-arid regions of central Oregon (1), central Washington (2), and the Treasure Valley of eastern Oregon and southwest Idaho (3). To our knowledge, this is the first report of the disease on a host crop in the mild, maritime region west of the Cascade Mountain Range and the first report of IYSV on leek seed crops in the United States, which complements a simultaneous report of IYSV on commercial leek in Colorado. The presence of IYSV may have implications for the iris and other ornamental bulb industries in western Oregon and western Washington. This report underscores the need for further research to determine the impact of the disease on allium crops and other hosts and the development of effective management programs for IYSV and the vector, Thrips tabaci. References: (1) F. J. Crowe and H. R. Pappu. Plant Dis. 89:105, 2005. (2) L. J. du Toit et al. Plant Dis. 88:222, 2004. (3) J. M. Hall et al. Plant Dis. 77:952, 1993. (4) H. F. Schwartz et al. Plant Dis. 91:113, 2007.
First Report of Peanut mottle virus in Forage Peanut (Arachis glabrata) in North America
Authors: Nischwitz C. , Maas A. L. , Mullis S. W. , Culbreath A. K. , Gitaitis R. D. 
Published: May 2007

Rhizoma peanut (Arachis glabrata Benth.) is a forage crop with increasing acreage (>10,500 ha) in the coastal plain region of the United States. Peanut mottle virus (PeMoV), a member of the family Potyviridae, is transmitted nonpersistently by aphids and seed-transmitted in A. hypogaea. Important hosts of the virus include peanut, soybean, and pea. During January of 2006 in Tifton, GA, immature rhizoma peanut plants identifier A176 with a lost PI number and PI 243334 exhibiting chlorotic ringspots were tested for viruses (potyviruses, Tomato spotted wilt virus [TSWV] and Cucumber mosaic virus [CMV]) frequently found in crops in the southeastern United States. All symptomatic plants tested were positive in the general potyvirus screen by indirect ELISA (Agdia, Inc., Elkhart, IN) and negative for TSWV and CMV. Leaves from two symptomatic plants of A176 and several asymptomatic genotypes were blotted onto FTA cards (Whatman Inc., Maidstone, UK) to bind viral RNA for preservation and processed according to the manufacturer's protocol. To determine the specific potyvirus identity, punch-outs from the FTA cards were used for reverse transcription (RT)-PCR (3) to test for PeMoV and Peanut stripe virus (PStV), both of which are found in A. hypogaea in Georgia. The forward primer (5′-GCTGTGAATTGTTGTTGAGAA-3′) and the reverse primer (5′-ACAATGATGAAGTTCGTTAC-3′) were specific for PeMoV and the forward primer (5′-GCACACACTTCTTGGC ATGG-3′) and reverse primer (5′-GCATGCCCTCGCCATTGCAA-3′) were specific for PStV (2). The primers are specific to the respective viral coat protein genes. Amplicons of the expected size (327 bp) were produced from symptomatic A176 and PI 243334 samples but not from the asymptomatic genotypes. The resulting PCR product was sequenced and a BLAST search in GenBank confirmed PeMoV (98 to 99% nt identity with Accession Nos. X73422 and AF023848). This finding is of significance because rhizoma peanuts are typically propagated by cuttings. Therefore, maintaining virus-free stock is critical. Although, PeMoV has been found in A. pintoi in Colombia (1), to our knowledge, this is the first report of PeMoV in rhizoma peanut (A. glabrata) peanut anywhere in the world. References: (1) A. A. Brandt et al. Plant Viruses Online: Descriptions and Lists from the VIDE Database, 2007. (2) R. G. Dietzgen et al. Plant Dis. 85:989, 2001. (3) R. D. Gitaitis et al. Phytopathology (Abstr.) 95(Suppl):S35, 2005.
Phytophthora Blight Caused by Phytophthora capsici on Pumpkin and Winter Squash in Texas
Authors: Isakeit T. 
Published: May 2007

Phytophthora blight of pumpkin and squash (Cucurbita spp.) has increased in importance in many production areas of the United States in recent years. This disease was seen on a 36-ha commercial field of several cultivars of pumpkin and winter squash (including Cucurbita maxima cvs. Prizewinner, Atlantic Giant, and Casper and C. pepo cvs. Howden, Festival, Sweet Dumpling, and Magic Lantern) in Yoakum County in the High Plains of Texas during August of 2006. At that time, 2% of the field was affected. A month later, after unusually frequent rain showers and higher-than-average precipitation, 78% of the field was lost in spite of an aggressive fungicide program following the initial diagnosis. Symptoms consisted of white, velvety growth on fruit, fruit rot, leaf blight, and wilt. Sporangia on fruit were papillate, ovoid to ellipsoid, and measured 37 to 40 × 21 to 23 μm. Isolations were made from tissue onto water agar and two isolates used for further study were maintained on corn meal agar. When isolates were paired on V8 agar with two Phytophthora capsici isolates from pepper (3) of opposite mating type, amphigynous antheridia and plerotic oospores 25 to 27 μm in diameter were produced. The morphological characteristics of the isolates were consistent with P. capsici (1). Four-week-old plants of C. maxima cv. Cinderella and C. pepo cvs. Festival and Sweet Dumpling growing in Metro-Mix 366 were inoculated with each isolate by placing 2 cm3 of a 6-week-old culture from lima bean agar (0.2% agar) adjacent to the base of each stem. The soil was then watered to saturation. There were four plants per 2.8-liter pot and two pots per isolate-cultivar combination. Plants were grown in the greenhouse at 18 to 27°C. The test was repeated once. Wilting and stem collapse were seen on inoculated plants 2 to 7 days later, sometimes with production of sporangia on stems. The pathogen was consistently reisolated from symptomatic plants, fulfilling Koch's postulates. These isolates were also pathogenic to pepper (Capsicum annuum). The affected field had been planted to pumpkins and winter squash the previous year when the grower saw similar symptoms on a few plants. In 2004, this field was planted to wheat. There are 1,350 ha of pumpkins produced in Texas, mostly in High Plains counties, and 730-ha squash produced throughout the state. To my knowledge, this is the first report of Phytophthora blight on pumpkin and winter squash in Texas. Phytophthora blight has been a long-standing problem of peppers grown in the Lower Rio Grande Valley of Texas (2), which is 900 km from Yoakum County. References: (1) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society. St. Paul, MN. 1996. (2) G. H. Godfrey. Plant Dis. Rep. 31:8, 1947. (3) B. Villalon. Phytopathology (Abstr.) 86(suppl):S118, 1996.
Blight of English Ivy (Hedera helix) Caused by Sclerotium rolfsii in Sicily
Authors: Pane A. , Raudino F. , Adornetto S. , Russo G. Proietto , Cacciola S. O. 
Published: May 2007

English ivy, Hedera helix L. (Araliaceae), an evergreen climbing vine is widely cultivated as an ornamental and foliage plant. In the summer of 2005, a severe blight of ivy plants trained as topiaries and grown in an open field was observed in a nursery near Giarre (eastern Sicily). Foliage of infected plants appeared lighter green and progressively turned bronze and withered. Eventually, the entire plant collapsed. Foliar symptoms were associated with basal stem and root rot. White, cottony mycelium and numerous sclerotia developed externally on the lower stem and on the soil around the affected plants. The disease was randomly distributed, affecting approximately 5% of plants in a stock of 1,500 English ivy plants. Sclerotium rolfsii Sacc. (teleomorph Athelia rolfsii (Curzi) Tu & Kimbrough) was consistently isolated from symptomatic basal stem tissues by disinfecting in 1% NaOCl and plating on potato dextrose agar (PDA) amended with 100 mg/liter of streptomycin sulfate. The isolated fungus was identified on the basis of morphological and cultural characteristics (2). On PDA, it produced a densely, floccose, white mycelium. Mycelium was septate with clamp connections at hyphal septa. Optimum growth temperature was 30 ± 2°C. Numerous small (0.5 to 1.9 mm in diameter) sclerotia developed on the colony surface; they were spherical, occasionally slightly ellipsoidal, quite uniform in size (modal value of the diameter 1.4 mm), with a smooth surface. The surface color of the sclerotia was initially white, turned to pinkish buff, then to olive-brown, and eventually to clove brown as sclerotia matured. Sclerotia were most numerous in the center as well as close to the edge of petri dishes. Pathogenicity of one isolate obtained from infected plants was confirmed by inoculating 10 1-year-old potted English ivy plants by placing mycelium-infested wheat kernels and sclerotia on the soil surface around the collar of each plant. Ten noninoculated plants served as control. Plants were held in a dew chamber for 48 h at 28°C and subsequently placed in a greenhouse where the temperature ranged between 25 and 31°C. Plants showed wilting within 3 weeks after inoculation. Fans of white mycelium and numerous sclerotia were produced on the basal stem of inoculated test plants. Noninoculated controls remained healthy. S. rolfsii was reisolated from infected plants to fulfill Koch's postulates. English ivy has been already reported as a host of S. rolfsii, the causative agent of southern blight in nurseries of ornamentals (1). However, to our knowledge, this is the first report of southern blight on English ivy in Italy. The disease may have been favored by warm summer temperatures and overwatering with a drip irrigation system. References: (1) A. R. Chase. Compendium of Ornamental Foliage Plant Diseases. The American Phytopathological Society, St. Paul, MN, 1992. (2) J. E. M. Mordue. Corticium rolfsii. No. 410 in: Description of Pathogenic Fungi and Bacteria. CMI. Kew, Surrey, UK, 1974.
Sawadaea Powdery Mildew of Box Elder (Acer negundo) in Wisconsin
Authors: Stanosz G. , Smith D. , Stanosz J. 
Published: May 2007

Box elder leaves affected by powdery mildew were collected from a single tree in an urban yard in the fall of 2006 in Madison, WI. As much as half of the area of the leaf blades, when viewed from above or below, was pale green-to-tan and necrotic. Mycelium was not visible to the eye on either the upper or lower leaf surfaces, but very sparse white mycelium was observed on the lower surface of leaves with the aid of a dissecting microscope. Chasmothecia were present singly or in groups of a few on the lower surface of leaves. Morphology of the chasmothecia, including simple and bifid appendages with uncinate to circinate apices, was sufficient to identify the pathogen to the genus Sawadaea (1). Other characters were not sufficiently distinct to make an identification of the species. However, DNA was extracted from the chasmothecia, and analysis of a 542-bp sequence of nuclear rDNA ITS (GenBank Accession No. EF122238) revealed a 100% match with the respective sequence obtained from Genbank for S. bicornis (Accession No. AB193380). A specimen from which these chasmothecia were obtained has been deposited in the U.S. National Fungus Collections (BPI 877328). S. bicornis is a European pathogen of maples, including box elder when grown there (1). Knowledge of the geographic distribution and hosts of Sawadaea powdery mildews in North America is extremely limited. S. bicornis was first reported in North America only recently, occurring in the states of Idaho and Washington on Norway maple (Acer platanoides) (3). The morphologically very similar European powdery mildew pathogen of maples, S. tulasnei, is known only from New York, Ohio, and Montreal, Canada (4), and an unidentified Sawadaea species on box elder has been reported from California (2). References (1) U. Braun. The Powdery Mildews (Erysiphales) of Europe. Gustav Fischer Verlag, Jena-Stuttgart-New York, 1995. (2) S. Hirose et al. Mycol. Res. 109:912, 2005. (3) C. Nischwitz and G. Newcombe. Plant Dis. 87:451, 2003. (4) J. Weiland and G. Stanosz. Plant Dis. 90:830, 2006.