bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Bipartite Geminivirus Infecting Tomatoes in Cuba
Authors: Martinez Y. , de Blas C. , Zabalgogeazcoa I. , Quiñones M. , Castellanos C. , Peralta E. L. , Romero J. 
Published: May 2007

Whitefly-transmitted geminiviruses have increased in their distribution and importance during the last decade, apparently due to a wider distribution of their vector Bemisia tabaci (Gennadius). In Cuba, symptoms of geminivirus disease have been observed since the early 1990s. A survey of geminivirus-caused diseases in tomato plants has been conducted since 1994 in the province of La Habana. The most severe symptoms were observed in the commercial varieties Campbell 28, Criollo Quivican, and HC 3880. In some plants the Israeli strain of tomato yellow leaf curl geminivirus (TYLCV) was detected (1). In other cases, a viral DNA with a genome size smaller than that of TYLCV that could not be amplified with primers specific for the Israeli strain was also detected by hybridization. In these samples a polymerase chain reaction amplification with broad-spectrum, degenerate primers designed for whitefly-transmitted bipartite geminivirus (2) was carried out. Two fragments of about 1.1 and 0.6 kb, corresponding to components A and B, respectively, were amplified, indicating that a bipartite geminivirus was present. The 1.1-kb fragment amplified from a sample showing strong leaf yellowing and slight curling was cloned and sequenced. A sequence of 1,174 nucleotides was obtained and compared with geminivirus sequences deposited in the GenBank, by multiple alignment (CLUSTAL W, European Bioinformatics Institute, Hinxton Hall, UK). Genetic distances were calculated by Kimura's two parameters method. Percentages of similarities obtained with the sequence were as follows: tomato mottle virus 78%, abutilon mosaic virus 73.8%, and tomato golden mosaic 61.8%. Partial sequences of the open reading frames AL1 and AR1 and the intergenic region were present. Percentages of similarities obtained with the intergenic region were as follows: tomato mottle virus 78.1%, sida golden mosaic virus 63%, bean dwarf mosaic virus 62.6%, abutilon mosaic virus 57.1%, and tomato golden mosaic virus 32%. These results suggest that we have detected in Cuban tomatoes a new bipartite geminivirus related to tomato mottle virus, and we propose that it be named Havana tomato virus. Frequency of distribution of viruses in commercial varieties and their relationship with the presence of whiteflies are currently being studied. References: (1) Y. Martinez et al. J. Phytopathol. 144:277, 1996. (2) M. R. Rojas et al. Plant Dis. 77:340, 1993.
First Report of Pratylenchus fallax on Turfgrass in Ontario
Authors: Yu Q. , Potter J. W. , Gilby G. A. 
Published: May 2007

During 1995 and 1997 surveys of golf courses throughout southern Ontario for plant parasitic nematodes, one Pratylenchus sp. with a heavily sclerotized cephalic area, lip region with three annules, females with spermatheca full of sperms, and crenate tail was found in 13 of 14 soil samples taken from fairways. Males were also found in the samples. Monoxenic cultures of the nematode were established on excised corn roots, each culture started from a single mature female. In cultures, males were common, averaging about one male per five females. Following a comparative microscope study of about 50 specimens (20 measured), the species was identified as Pratylenchus fallax Seinhorst, 1968. Bluegrass (Poa pratensis L.) was the main type of grass in the fairways surveyed. P. fallax may cause significant damage to turfgrass by directly destroying the roots, and the wounded roots become vulnerable to secondary infection by soilborne pathogens (1). The nematode has been found once in Quebec, Canada, in 1976 (2). This is the first report of Pratylenchus fallax in Ontario. References: (1) S. G. Fushtey and F. D. McElroy. Can. Plant Dis. Surv. 57:54, 1977. (2) P. W. Willis et al. Plant Dis. Rep. 60:207, 1976.
First Report of Banana Streak Badnavirus in Plantain Landraces in Southern Cameroon, Central Africa
Authors: Gauhl F. , Pasberg-Gauhl C. , Hughes J. d'A. 
Published: May 2007

Banana streak badnavirus (BSV) has been reported from Musa spp. in many parts of West Africa, including Benin, Côte d'Ivoire, Ghana, and Nigeria (1). Symptoms of BSV infection in Musa spp. are sometimes similar to and confused with those caused by cucumber mosaic virus (CMV). BSV is prevalent in areas of southern Nigeria bordering Cameroon, and the disease may also be present in other Central African countries. In June 1996, six leaf samples with viruslike yellow/chlorotic streak symptoms were collected from plantain in the four villages, Awae, M'Balmayo, Nkolfep, and Nkolfoulou, within a 60-km radius of Yaoundé, Cameroon's capital. The samples were indexed for BSV and CMV by both triple antibody sandwich indirect enzyme-linked immunosorbent assay (TAS-ELISA) and immunosorbent electron microscopy (ISEM) to ascertain the presence of these two viruses. The TAS-ELISA was performed with rabbit polyclonal antiserum (obtained from B. E. L. Lockhart, University of Minnesota) for trapping and mouse polyclonal antiserum (obtained from G. Thottappilly, IITA) for detection. Out of the six samples, one tested strongly positive (>×2 A405 of the healthy control) and four were weakly positive (<×2 but >×1.5 A405 of the healthy control) for BSV by TAS-ELISA. However, all six samples contained BSV particles when examined by ISEM with rabbit polyclonal antiserum (from B. E. L. Lockhart) for trapping. None of the samples tested positive for CMV. These results confirm that BSV is present in Cameroon and that BSV is likely to be the causal agent of the symptoms. Reference: (1) C. Pasberg-Gauhl et al. Plant Dis. 80:224, 1996.
First Report of Pythium myriotylum in a Tobacco Seedling Float System in South Carolina
Authors: Anderson M. G. , Fortnum B. A. , Martin S. B. 
Published: May 2007

Float bay production of seedlings accounts for approximately 62% of tobacco (Nicotiana tabacum L.) transplant production in South Carolina. Float systems utilize styrofoam trays containing soilless media that float in plastic-lined bays filled with nutrient solution. Oomycete fungi with motile zoospores, such as Pythium spp., can devastate plants grown hydroponically (3). This poses a serious concern for growers because no fungicides are labeled for control of Pythium spp. in nutrient solutions for tobacco greenhouse float systems. In May 1996, Pythium myriotylum Drechs. was recovered from diseased seedlings produced in float bays in Walterboro, SC. The pathogen was isolated on PAR selective medium (2). Koch's postulates were fulfilled by inoculating plants in an experimental float bay and then reisolating the pathogen on PAR from symptomatic plants. Diseased plants appeared chlorotic and stunted, with water-soaked lesions on the stem. Root systems were severely necrotic and infected plants could not be used as transplants. Disease development was confined to plants sharing a common nutrient solution in individual bays. Within affected bays nearly 100% of plants were diseased, suggesting pathogen spread through the nutrient solution. At the time of disease onset, the grower was attempting a second crop of transplants. The high late-season temperatures were favorable for P. myriotylum, which has a growth optimum of 37°C. Primary inoculum could potentially arise from contaminated media or water and/or improper sanitation procedures in greenhouse maintenance. Pathogenic isolates of several Pythium spp. were found in commercial potting media in North Carolina in 1995 (1). References: (1) D. K. Cartwright et al. Plant Dis. 79:538, 1995. (2) S. N. Jeffers and S. B. Martin. Plant Dis. 70:1038, 1986. (3) M. E. Stanghellini and S. L. Rasmussen. Plant Dis. 78:1129, 1994.
Preliminary Identification of Maize Stripe Tenuivirus in Thailand
Authors: Sdoodee R. , Teakle D. S. , Louie R. 
Published: May 2007

Maize stripe tenuivirus (MStV) and its planthopper vector, Peregrinus maidis, occur in many tropical and subtropical regions worldwide (2). However, MStV has not been reported from the southeastern Asia continent. In January 1990, five of 200 Sorghum bicolor plants growing in Hat Yai, Thailand, showed symptoms typical of MStV, i.e., chlorotic spots, streaks, and wide bands on the younger leaves. Colonies of P. maidis also were present in leaf whorls of both symptomatic and asymptomatic sorghum plants. In December 1991, two sweet corn plants (Zea mays cv. Thai Super Sweet Composite 1 DMR) growing in the same area showed similar symptoms and were infested with P. maidis. When examined by phase-contrast microscopy, sap from chlorotic leaf tissue of one sweet corn plant had needle-shaped crystals typical of MStV infection (1). Sap from asymptomatic sweet corn plants had no crystals. In April 1996. maize cv. Chieng Mai 90 with MSt-like symptoms and also infested by P. maidis was collected from Hat Yai. Leaves were freeze dried, sent to Ohio, and tested by F(ab′)2 enzyme-linked immunosorbent assay (ELISA). Positive control samples were fresh or freeze-dried leaves of sweet corn infected with MStV from Australia, Costa Rica, Malawi, Mauritius. and the U.S. Leaves of asymptomatic glasshouse-grown sweet corn seedlings were negative controls. In the ELISAs, the OD values at A 405 of the Thailand sample with MStV symptoms was 1.00, compared with 0.33 to 1.52 for the positive control samples and 0.00 to 0.02 for fresh or freeze-dried negative controls. The microscopic and serological results indicate the occurrence of MStV in Thailand. References: (1) O. E. Bradfute and J. H. Tsai. Phytopathology 80:715, 1990. (2) R. E. Gingery et al. J. Gen. Virol. 64:1765, 1983.
First Report of a Leaf Spot Caused by Cladosporium oxysporum on Greenhouse Tomato
Authors: Lamboy J. S. , Dillard H. R. 
Published: May 2007

In a commercial greenhouse in upstate New York, dark brown, angular lesions were first observed in April on lower, older leaves of 4-month-old tomato plants (Lycopersicon esculentum Mill. ‘Jumbo’). Chlorosis frequently developed around the lesions. Removal of the infected leaves reduced the rate of epidemic development. However, by July, lesions were present throughout the plant canopy, up to 2 m. The irregularly shaped lesions varied in size from 1 to 5 mm, frequently with tan-colored centers initially. Conidia developed in the center of the lesions, primarily on the outer, or adaxial side of the leaf, but were infrequent on the abax-ial surface. This contrasts with Cladosporium leaf mold caused by Fulvia fulva, in which the conidia develop as a velvety brown patch in lesions on the abaxial, or underside of the leaf, accompanied by chlorosis on the upper side of the leaf (1). The conidia ranged in shape from oval or li-moniform (5 to 6 μm in diameter) to cylindrical (5 to 6 μm wide, 7 to 20 μm long). The fungus was identified as Cladosporium oxysporum Berk. & M. A. Curtis (3) by C. J. K. Wang and J. M. McKemy of the State University of New York College of Environmental Science and Forestry in Syracuse, NY. Koch's postulates were fulfilled with a tuft of mycelium and conidia grown on potato dextrose agar as inoculum on fully expanded leaves of 5-week-old tomato plants, cv. Jumbo. Two weeks later, characteristic sporulating lesions developed on inoculated plants, about 1 cm from the inoculation site. Within 3 weeks, in the research greenhouse, the disease spread to healthy tomato plants in the vicinity, confirming the highly infectious nature observed in the commercial greenhouse. The fungus was reisolated from inoculated leaves and also from the adjacent naturally infected plants. C. oxysporum was previously reported as the causal agent of a leaf spot disease of pepper (2) and also a storage disease of ripe tomato fruit (4). To the best of our knowledge this is the first report of C. oxysporum causing disease on tomato foliage. References: (1) E. E. Chamberlain. N.Z. J. Agric. 45:136, 1932. (2) A. M. Hammouda. Plant Dis. 76:536, 1992. (3) J. M. McKemy and G. Morgan-Jones. Mycotaxon 41:397, 1991. (4) S. Singh et al. Indian J. Microbiol. 23:133, 1983.
First Report of Powdery Mildew Caused by Erysiphe heraclei on Celery in North America
Authors: Koike S. T. , Saenz G. S. 
Published: May 2007

Since 1994, a fungal disease has been affecting celery (Apium graveolens) grown for seed in the central coast region of California. White, ectophytic mycelia and conidia, characteristic of a powdery mildew, were present on compound umbels, including the involucre, rays, raylets, flowers, and fruits. Celery with powdery mildew had twisted flower petals, and the disease possibly contributed to premature senescence and drying of the fruits. Powdery mildew was not observed on leaves. Mycelial growth was effused and amphigenous and had lobed appressoria. Conidiophores were straight, and cylindrical foot cells were followed by a longer cell and one or two shorter cells. Conidia were produced singly and were 36 to 44 × 11 to 16 μm. Fibrosin bodies were not observed. Germ tubes were located at the ends of conidia and formed lobed appressoria. Cleistothecia were not present. Based on these characteristics, the fungus was identified as Erysiphe heraclei (1). In California, parsley (Petroselinum crispum) is a host of E. heraclei (4), and parsley is grown in the same region as celery seed crops. To determine if parsley was an alternative host of the celery powdery mildew, infected celery umbels were gently pressed onto adaxial surfaces of leaves on 2-month-old greenhouse grown parsley cvs. Italian Plain and Triple Curled. Inoculated plants were incubated 48 h in a moist chamber at 22°C, then transferrred to a greenhouse at 22 ± 2°C / 16 ± 2°C day/night temperatures, 75% relative humidity, and natural light. After 12 to 14 days, powdery mildew was observed on both parsley cultivars. Uninoculated control plants did not develop the disease. This is the first report of powdery mildew on celery in North America. Previous reports list E. heraclei on celery in Chile, the former Czechoslovakia, France, Iraq, Italy, and the former USSR (Georgia region). In the U.S., E. heraclei is reported on carrot (Daucus carota) (2), parsley (4), meadow parsnip (Zizia aptera and Z. aurea) (3), and now celery. References: (1) H. J. Boesewinkel. Bot. Rev. 46:167, 1980. (2) D. F. Farr et al. Fungi on Plants and Plant Products in the United States. American Phytopathological Society, St. Paul, MN. (3) K. A. Hirata. Host Range and Geographic Distribution of the Powdery Mildew Fungi. Jpn. Scientif. Soc. Press, Tokyo. (4) S. T. Koike and G. S. Saenz. Plant Dis. 78:1219, 1994.
First Report of Marssonina brunnea f. sp. brunnea on Hybrid Poplar in the Pacific Northwest
Authors: Newcombe G. , Callan B. E. 
Published: May 2007

Marssonina brunnea (Ellis and Everh.) Magnus f. sp. brunnea Spiers is the most damaging Marssonina sp. affecting Populus spp. in the world (1). First described from eastern North America at the turn of the century, it subsequently became a serious disease of hybrid poplar in Europe in the 1960s and in New Zealand in 1976 (1). It causes punctiform black spots on both leaf surfaces and lesions on petioles and young stems. Symptoms are typically most severe in the lower portion of the crown of trees. Not observed in the Pacific Northwest on hybrid poplar until recently, it is still only present in a few locations. Voucher specimens from near Ilwaco, WA, at the mouth of the Columbia River, and from near Har-rison Mills, British Columbia, were deposited in the Herbarium at the Pacific Forestry Centre (DAVFP 25202 and 24958, respectively). The fungus was identified as M. brunnea by its conidial morphology. Conidia were hyaline, uniseptate, mostly straight, and narrowly obovoid, and, when measured in lactoglycerol, averaged 16.1 μm × 5.0 μm (WA collection) and 15.7 μm × 5.6 μm (BC collection). The septum is located about 30% of the total conidium length from the conidium base. Inoculations of leaf disks (1) proved that the species was pathogenic to hybrids but not to local P. tremuloides Michx., and thus the fungus was identified as M. brunnea f. sp. brunnea. Variation in resistance, from light spotting to severe, was noted both among 12 P. trichocarpa Torr. & A. Gray × P. deltoides J. Bartram ex. Marsh. hybrid clones in the Ilwaco plantation and among 56 hybrid clones in the inoculation study. Reference: (1) A. G. Spiers. Eur. J. For. Pathol. 18:140, 1988.
Broccoli Raab as a Host of Alternaria brassicae in California
Authors: Koike S. T. 
Published: May 2007

In the fall of 1996, commercial plantings of broccoli raab or rappini (Brassica rapa subsp. rapa) in the Salinas Valley, Monterey County, were damaged by a disease previously unreported in California. Symptoms consisted of small (7 to 8 mm in diameter), circular to oblong, brown to light tan leaf spots that contained characteristic concentric rings. An Alternaria sp. having conidia with prominent beaks and spores produced singly or in chains of two was consistently observed on and isolated from the host. Conidia from naturally infected broccoli raab measured 144.5 to 194.5 × 22.2 to 30.6 μm (beak length ranged from 33.3 to 75.0 μm). The isolates were identified as Alternaria brassicae (Berk.) Sacc. (2). Pathogenicity was confirmed by culturing five representative isolates on sterilized 20% V8 juice solution for 10 days under a 12-h light/12-h dark cycle, filtering the suspensions through cheesecloth, obtaining spore concentrations of 30,000 conidia per ml, and spraying suspensions onto 6-week-old seedlings of broccoli raab cv. Spring Raab. Plants were incubated in a humid chamber for 48 h and then maintained in a greenhouse. After 5 to 7 days, leaf spots similar to the original symptoms developed on all inoculated plants. The pathogen was reisolated and identified as A. brassicae. Control plants sprayed with distilled water remained symptomless. The inoculation test was repeated and results were the same. Because of the extensive plantings of cole crops in the Salinas Valley, isolates from broccoli raab were inoculated onto two sets each of broccoli (Brassica oleracea subsp. italica cv. Greenbelt), Chinese cabbage (Brassica campestris subsp. pekinensis cv. Cha-Cha), and Japanese mustard (Brassica campestris subsp. nipposinica cv. Mizuna), using the method described above. After 5 to 7 days, similar leaf spots developed on all inoculated plants and A. brassicae was reisolated and identified. Control plants sprayed with distilled water remained symptomless. This fungus does not appear to be a pathogen specific to particular cole crops in this area (1). For California, this is the first report of black spot caused by A. brassicae on commercially grown broccoli raab. References: (1) S. T. Koike. Plant Dis. 80:822, 1996. (2) E. G. Simmons. Mycotaxon 55:55, 1995.
First Report of Banana Streak Virus Infecting Sugarcane and Arrowroot in Colombia
Authors: Reichel H. , Belalcázar S. , Múnera G. , Arévalo E. , Narváez J. 
Published: May 2007

We have recently reported on the presence of banana streak virus (BSV) affecting plantains (Musa spp.) in Colombia (2). BSV is serologically related to sugarcane bacilliform virus and has been found to be transmitted by the pink mealybug (Saccharicoccus sacchari) from sugarcane to banana (1). In the vicinity of affected plantain crops in the localities of Andes (Antioquia) and Montenegro (Quindio), we observed sugarcane (Saccharum officinarum L.) plants with chlorotic streaks on their leaves, as well as arrowroot (Canna edulis Ker-Gawl.) plants with mild mosaic symptoms. The foliar tissue of symptomatic plants of these two species was tested for BSV and cucumber mosaic virus (CMV) by double antibody sandwich-enzyme-linked immunosorbent assay with commercial polyclonal antisera (Agdia Inc., Elkhart, IN). BSV was detected in samples of both plant species, whereas CMV was not detected in either one. Immunosorbent electron microscopy analysis of BSV-infected, symptomatic, foliar tissue of sugarcane showed the presence of viral-like bacilliform particles measuring approximately 150 × 30 nm, typical of BSV. This is the first report of BSV infecting Saccharum officinarum in Colombia and the first report of Canna edulis as a host for this virus. References: (1) B. E. L. Lockhart and L. J. C. Autrey. Plant Dis. 72:230, 1988. (2) H. Reichel et al. Plant Dis. 80:463, 1996.
Occurrence of Vine Decline Diseases of Melons in Honduras
Authors: Bruton B. D. , Miller M. E. 
Published: May 2007

A survey of vine decline diseases of melons (Cucumis melo L.) was conducted on three geographically separate farms (12 fields) in the area of San Lorenzo, Honduras, during the spring of 1996. Symptoms were typical of the vine declines in that the leaves began yellowing and collapsing in the crown just prior to harvest and the decline radiated outward. Crown lesions, typical of many of the vine declines, were observed infrequently. Most plants exhibited no crown lesion. Roots exhibited brown lesions and root corking, and were generally lacking root hairs, although the roots were not macerated. Fruit were small sized, low in sugars, and sunburned. Isolations were made from the crown area, primary root, and secondary roots of affected plants by excising 3- to 5-mm pieces and surface sterilizing for 30 to 60 s with 0.5% sodium hypochlorite. Four tissue pieces from each plant part were placed on 2.0% water agar plus 0.1 g of streptomycin sulfate per liter and their identity maintained. Plates were examined for fungal growth daily for 5 days and hyphal tips from all colonies were transferred to potato dextrose agar and Synthetischer nährstoffärmer agar (2) to allow for sporulation. Rhizoctonia solani Kühn was the predominant fungus isolated from affected plants in several fields, with an incidence as high as 75%. A Pythium sp. was isolated from primary and secondary roots of 50% of the plants on the Santa Rosa farm. Vines exhibiting tan to light brown crown lesions either on one side of the vine or encompassing the crown, but without gumming, always produced colonies of Fusarium semitectum Berk. & Ravenel. Fusarium solani (Mart.) Appel & Wollenweb. emend. W. C. Snyder & H. N. Hans. was isolated from roots of more than 30% of the plants, although this is not unusually high. Crown lesions typical of charcoal rot were observed in some fields, with Macrophomina phaseolina (Tassi) Goidanich being isolated from 65% of the plants in one field. Charcoal rot was a minor problem in all fields but one. Didymella bryoniae (Auersw.) Rehm was not isolated from any of the plants. A Stagonospora-like fungus, which has been demonstrated recently as a potential contributor to vine decline (1), was isolated on 17% of the plants from five fields on the Embarcadero Farm. Monosporascus cannonballus Pollack & Uecker was isolated infrequently in one field on the Santa Rosa Farm. This is the first report of M. cannonballus and a Stagonospora-like fungus in Honduras. References: (1) M. E. Miller et al. Phytopathology 86:S3, 1996. (2) H. I. Nirenberg. Mitt. Biol. Bundesanst. Land Forstwirtsch. Berlin-Dahlem. 169:1, 1976.