bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of Southern Blight Caused by Sclerotium rolfsii on Laurustinus
Authors: Polizzi G. , Vitale A. , Parlavecchio G. 
Published: May 2007

Laurustinus (Viburnum tinus L.), native to the Mediterranean Region, is an evergreen shrub commonly used as a specimen shrub or small tree or used in border plantings. During August 2003, a blight occurred on 2-year-old-plants of laurustinus growing in pots in a nursery in eastern Sicily (Italy). Disease incidence ranged from 2 to 5% across the field. Symptoms included 3 to 4 cm long lesions and the development of white mycelial strands and brown, 1.0 to 1.8 mm, nearly spherical sclerotia on the crown of plants at the soil line that are typical of Sclerotium rolfsii Sacc. The foliage of infected plants wilted, followed by a sudden collapse of the plant. The fungus was consistently isolated on acidified potato dextrose agar (PDA) (pH 4.5) by plating symptomatic tissues that were surface disinfested (1.2% NaOCl) for 1 min. and rinsed in sterile water. Pathogenicity tests were performed by sprinkling 50 sclerotia, obtained from infected oat kernels (2), on the soil surface around the collar of each of 10 healthy, potted 1-year-old plants of laurustinus. Five of the plants were previously wounded on the crown 1.5 cm above or below the soil line with a sterile needle. Five noninoculated plants served as controls. All plants were maintained at 25 ± 2°C and enclosed for 72 hr in polyethylene bags (90 to 95% relative humidity). Blight symptoms similar to those seen in nursery were observed on inoculated plants 20 to 25 days after inoculation, while no symptoms developed on control plants. Koch's postulates were fulfilled by reisolation of the fungus on acidified PDA from all infected laurustinus plants. S. rolfsii was previously recorded on Prague viburnum (Viburnum × pragense L.) as the causal agent of southern blight (1). To our knowledge, this is the first report of southern blight caused by S. rolfsii on laurustinus. References: (1) A. Hagan. Southern blight on flowers, shrubs, and trees. On-line publication ANR-1157. Alabama A & M, and Auburn University ( www.aces.edu/dept/extcomm/publications/html ). (2) R. Rodriguez-Kabana et al. Plant Dis. Rep. 59:5, 1975.
First Report of Downy Mildew on Basil (Ocimum basilicum) in Italy
Authors: Garibaldi A. , Minuto A. , Minuto G. , Gullino M. L. 
Published: May 2007

Sweet basil (Ocimum basilicum) is an economically important herb in several Mediterranean countries. Approximately 80 ha are grown annually in Italy for fresh and processed consumption. In 2003, a damaging foliar disease was observed in several greenhouses located in the Liguria Region of northern Italy. More that 50% of the plants were affected. Leaves of infected plants were initially slightly chlorotic, especially near the central vein. Within 2 to 3 days, a characteristic gray, furry growth was evident on the lower surface of infected leaves. These symptoms sometimes occurred on the top sides of leaves. Although the distribution of the disease was generally uniform, symptoms appeared first in a patchy pattern in the central part of the greenhouses where air temperature and relative humidity were highest. Where air circulation was apparently poor, bottom leaves were severely affected by the disease. Microscopic observations revealed conidiophores branching two to seven times. Conidiophores with a length of 250 to 500 μm (average 350 μm) ended with sterigmata bearing single conidia. Conidia measured 15 to 25 × 20 to 35 μm (average 22 × 28 μm) and were elliptical and grayish in mass. The pathogen was identified as a Peronospora sp. based on its morphological characteristics (3). Pathogenicity was confirmed by inoculating leaves of 40-day-old healthy plants with a conidial suspension (1 × 105 conidia per ml). Three containers containing 150 plants each of O. basilicum cv. Genovese gigante were used as replicates. Noninoculated plants served as controls. Inoculated and noninoculated plants were maintained in a growth chamber at 20°C (12 h of light per day) and 90 to 95% relative humidity. The pathogenicity test was carried out twice. After 6 days, typical symptoms of downy mildew developed on the inoculated plants and a Peronospora sp. was observed on the leaves. Noninoculated plants did not show symptoms. To our knowledge, this is the first report of a Peronospora sp. on basil in Italy. Peronospora sp. and P. lamii were previously reported on sweet basil in Uganda (1,2). References: (1) C. G. Hansford. Rev. Appl. Mycol. 12:421, 1933. (2) C. G. Hansford. Rev. Appl. Mycol. 17:345, 1938. (3) D. M. Spencer. The Downy Mildews. Academic Press, N.Y., 1978.
First Report of Chickpea Chlorotic Dwarf Virus Infecting Spring Chickpea in Syria
Authors: Kumari S. G. , Makkouk K. M. , Attar N. , Ghulam W. , Lesemann D.-E. 
Published: May 2007

During May 2003, a high incidence of symptoms suggestive of virus infection in spring chickpea were observed in many fields in Al-Ghab Valley, Syria, the ICARDA farm (near Aleppo, Syria), as well as in other locations in northern Syria, including the Idleb governorate. Symptoms observed were yellowing, stunting, and necrosis. A total of 1,345 chickpea samples with these symptoms (331 from Al-Ghab Valley, 269 from the ICARDA farm, and 745 from the Idleb governorate) were collected and tested for the presence of five viruses with tissue-blot immunoassay (TBIA) (4) at the Virology Laboratory of ICARDA, using the following antisera: monoclonal antibodies for Faba bean necrotic yellows virus (FBNYV, genus Nanovirus) (1); Bean leafroll virus (BLRV, family Luteoviridae) (4B10) (3); Beet western yellows virus (BWYV, genus Polerovirus, family Luteoviridae [ATCC PVAS-647, American Type Culture Collection, Manassas, VA]); and Soybean dwarf virus (SbDV, family Luteoviridae, [ATCC PVAS-650]) and polyclonal antibodies for Chickpea chlorotic dwarf virus (CpCDV, genus Mastrevirus, family Geminiviridae, provided by H. J. Vetten, BBA, Braunschweig, Germany). The most common virus present was BWYV (detected in 54.1% of samples tested), followed by CpCDV (19.2%), BLRV (10.2%), and FBNYV (5.5%). SbDV was not detected in any of the samples tested. Using immunosorbent electron microscopy, infected chickpea samples revealed low numbers of geminivirus-like particles after 15 min of incubation on CpCDV antiserum-coated grids. When CpCDV was purified from infected chickpea plants, the virus coat protein was 32 kDa with sodium dodecyl sulfate-polyacrylamide gel electrophoresis typical of CpCDV coat protein (2) and reacted strongly with CpCDV antiserum in western blots. The CpCDV vector in Syria was found to be Orosius albicinctus Distant, and is thought to be similar to Orosius orientalis (Matsumura), the reported vector of CpCDV (2). FBNYV, BWYV, and BLRV infection of chickpea have been previously reported from Syria, but to our knowledge, this is the first report of CpCDV infecting chickpea in Syria. References: (1) A. Franz et al. Ann. Appl. Biol. 128:255, 1996. (2) N. M. Horn et al. Ann. Appl. Biol. 122:467, 1993. (3) L. Katul. Characterization by serology and molecular biology of bean leaf roll virus and faba bean necrotic yellows virus. Ph.D. thesis. University of Gottingen, Germany, 1992. (4) K. M. Makkouk and A. Comeau. Eur. J. Plant Pathol. 100:71, 1994.
First Report of Powdery Mildew Caused by Erysiphe viburni on Viburnum tinus in California
Authors: Koike S. T. , Shishkoff N. 
Published: May 2007

In June 2003, landscape and potted nursery plants of laurustinus (Viburnum tinus) in Monterey County, California, were found to be infected with a powdery mildew. White, ectophytic mycelial and conidial growth were present primarily on adaxial leaf sides with only sparse growth on abaxial surfaces. Severely infected leaves were buckled and slightly twisted. Affected leaf tissue exhibited slight purple-to-brown discoloration. Appressoria were opposite and lobed. Conidia were produced singly, cylindrical in shape, and measured 31 to 42 × 14 to 19 μm. No fibrosin bodies were observed in the conidia, and the conidia germinated at the ends. Ascomata were not observed. The fungus was identified as Erysiphe (section Microsphaera) viburni Duby (= Microsphaera sparsa Howe = Microsphaera penicillata [M. sparsa is not completely synonymous with M. penicillata because M. sparsa is defined as only those mildews that attack viburnum, whereas M. penicillata was defined as attacking dogwood, alder, etc.]) (1,2). Pathogenicity was demonstrated by gently pressing infected leaves with abundant sporulation onto recently expanded leaves of four, large, potted laurustinus in standard 5-gallon nursery containers (19 liters). Twelve leaves per plant were inoculated. The plants were incubated in a greenhouse (23 to 25°C). After 9 to 10 days, powdery mildew colonies developed on approximately 50% of the inoculated leaves. Such colonies were morphologically similar to the original fungus. Uninoculated control plants did not develop powdery mildew. Using the same technique, inoculating fully mature leaves of the same plants did not result in disease. To our knowledge, this is the first report of Erysiphe viburni infecting V. tinus in California. At some landscaped areas the powdery mildew was extremely severe, causing plants to take on a whitish appearance and resulting in all new foliage being misshapen. E. viburni has also been reported to infect V. japonicum in California. References: (1) U. Braun. The Powdery Mildews (Erysiphales) of Europe. Gustave Fischer. New York, 1995. (2) U. Braun and S. Takamatsu. Schlechtendalia 4:1, 2000.
First Report of White Mold Caused by Sclerotinia sclerotiorum on Blue Marguerite (Felicia amelloides) in Italy
Authors: Garibaldi A. , Minuto A. , Gullino M. L. 
Published: May 2007

Felicia amelloides (Asteraceae family), also known as blue marguerite, is cultivated as a potted plant in Italy and increasingly used for ornamental purposes. In winter 2002, plants grown outdoors in 14-cm-diameter pots (2 liters) in commercial farms near Albenga (northern Italy) showed leaf yellowing. At the soil level, soft and watery tissues covered with whitish mycelium were evident. Later, dark brown sclerotia differentiated from the mycelium. As necrosis progressed, infected plants wilted and died. Sclerotinia sclerotiorum (1) was consistently recovered from infected stem pieces of F. amelloides that were disinfested for 1 min in 1% NaOCl and plated on potato dextrose agar (PDA) amended with 100 ppm of streptomycin sulfate. Sclerotia produced on PDA were ellipsoid and measured 1.3 to 6.1 × 1.1 to 3.3 mm (average 2.9 × 2.3 mm) (2). Pathogenicity of three isolates (used as a mixture and obtained from infected plants from the same farm) was confirmed by inoculating 90-day-old plants grown in 14-cm-diameter pots. Inoculum that consisted of wheat kernels infested with mycelium and sclerotia of each isolate was placed on the soil surface around the base of each of 20 plants. Ten noninoculated plants served as controls. The inoculation trial was repeated. All plants were kept outdoors at temperatures ranging between 5 and 26°C and watered as needed. All inoculated plants developed symptoms of leaf yellowing, followed by the appearance of white mycelium within 15 days, and then eventually wilted. Control plants remained symptomless. White mycelium and sclerotia developed on infected tissues, and S. sclerotiorum was reisolated from inoculated plants. To our knowledge, this is the first report of white mold of F. amelloides caused by S. sclerotiorum in Italy as well as elsewhere in the world. References: (1) N. F. Buchwald. Den. Kgl. Veterin.er-og Landbohojskoles Aarsskrift, 32:75, 1949. (2) C. M. Messiaen et al. Les Maladies des Plantes Maraichères. INRA, Paris, 1991.
Occurrence of Turnip Scab Caused by Phytotoxin-Producing Streptomyces spp.
Authors: Embleton Jean , King Russell R. , Lawrence Harold C. 
Published: May 2007

Turnips (Brassica rapa L var. rapifera) purchased from a New Brunswick supermarket in the winter of 2003 contained discernable corky scab-like lesions on their surfaces. The turnips were surface-disinfested with a warm-water rinse, and microorganisms from excised lesions were isolated with methodologies developed for the specific isolation of Streptomyces spp. (1). Nine isolates morphologically characteristic of Streptomyces scabies strains (2) were subsequently examined for pathogenicity on potato mini-tubers and production of the scab phytotoxin, thaxtomin A (1). Four of the nine isolates proved pathogenic on potato mini-tubers. When grown on an oatmeal broth medium, only the pathogenic isolates generated thin-layer chromatographic detectable quantities of the requisite phytotoxin, thaxtomin A (1). Previous greenhouse studies have demonstrated the ability of pathogenic Streptomyces spp. isolated from scab lesions on potatoes to infect turnips (2). To our knowledge, this is the first investigation to confirm the presence of thaxtomin A producing isolates on field-grown turnips. References: (1) R. R. King et al. Am. Potato J. 68:675, 1991. (2) R. Loria et al. Plant Dis. 81:836, 1997.
Witches'-broom of Bakraee (Citrus reticulata hybrid) in Iran
Authors: Djavaheri M. , Rahimian H. 
Published: May 2007

Symptoms, resembling those of witches'-broom disease of lime (WBDL), consisting of proliferation and growth of spindly shoots, rosetting, development of stunted, pale green, cupped leaves, and long thin thorns were observed on some bakraee (Citrus reticulata hybrid) trees, the major rootstock species in Ghazi-Ghale (Hormozgan Province) and Kahnouj (Kerman Province) in southern Iran. Vein clearing, mottling, and mild to severe yellowing of leaves was evident on some rosetted flushes. The disease occurred sporadically, and only some branches of the tree displayed the symptoms. Sour lime (Citrus aurantifolia) trees with symptoms of WBDL were also encountered in adjacent citrus groves in the area where an association of “Candidatus Phytoplasma aurantifolia” with diseased trees was previously established. Total nucleic acids were extracted from symptomatic as well as apparently healthy bakraee (1). The nucleic acids were subjected to nested polymerase chain reaction (PCR) amplification with the universal primers R16mF2/R16mR1, followed by R16F2n/R16R2 (2). The PCR program consisted of an initial denaturation at 94°C for 2 min, followed by 40 cycles of 1 min at 94°C, 2 min at 55°C, and 3 min at 72°C. After a final extension of 10 min at 72°C, the samples were electrophoresed on agarose gels, and the DNA fragments were stained with ethidium bromide and visualized under ultraviolet light. An expected 1.2-kb product was amplified in DNA preparations from broomed bakraee and WBDL-affected sour lime trees. No such amplicon was detected in similar DNA extracts of asymptomatic trees. These results demonstrated an association of a phytoplasma with witches'-broom disease of bakraee. However, its relationship with “Candidatus Phytoplasma aurantifolia” remains to be determined. References: (1) S. L. Dellaporta et al. Plant Mol. Biol. Rep.1:19, 1983. (2) I. M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998.
First Report of Tomato mosaic virus on Hibiscus rosa-sinensis in China
Authors: Huang J. G. , Fan Z. F. , Li H. F. , Tian G. Z. , Hu J. S. 
Published: May 2007

Hibiscus rosa-sinensis Linn., family Malvaceae, is an attractive horticultural plant originating from China. Five viruses infecting H. rosa-sinensis that have been characterized previously are Hibiscus chlorotic ringspot virus (HCRSV, genus Carmovirus), Hibiscus latent ringspot virus (HLRSV, genus Nepovirus), Hibiscus yellow mosaic virus (genus Tobamovirus), Eggplant mottled dwarf virus (EMDV, genus Nucleorhabdovirus), and Okra mosaic virus (OkMV, genus Tymovirus) (2). Recently, two novel tobamoviruses infecting H. rosa-sinensis were characterized in Singapore and Florida (1). In this study, viral symptoms were observed on H. rosa-sinensis in Nanyang City in Henan Province, China. The systemic symptoms included dark and light green mosaic in young leaves, leaf puckering and malformation on older leaves, and significant stunting. Rod-shaped virus particles were isolated from H. rosa-sinensis expressing systemic symptoms. The virus was transmitted mechanically to 10 species from three families. Symptoms expressed on these plants included systemic leaf chlorosis and distortion on Lycopersicum esculentum, systemic mosaic on Capsicum annuum, Nicotiana tabacum, and Physalis floridana, and systemic chlorosis on Glycine max. N. tabacum-Xanthi nc and Datura stramonium were asymptomatic. The virus also produced chlorotic and necrotic local lesions on Chenopodium quinoa, C. amaranticolor, and C. murale. The virus was propagated in L. esculentum, N. tabacum, and P. floridana. Virions purified from systemically infected N. tabacum contained a single-stranded RNA of approximately 6.4 kb and a coat protein (CP) of approximately 17.6 kDa. The double-stranded RNA profile revealed a single band of approximately 6.4 kb. Sap extracted from virus-infected plants reacted positive with an antiserum prepared against Tobacco mosaic virus (TMV) using an antigen-coated plate enzyme-linked immunosorbent assay. The CP gene was amplified by reverse transcription-polymerase chain reaction with primers specific to Tomato mosaic virus (ToMV) and sequence data obtained from the resulting amplification product. The CP gene consisting of 159 amino acids (GenBank Accession No. AY313136) shared 99.37% identity with the ToMV Queensland isolate (GenBank Accession No. AF332868). On the basis of biology, serology, properties of virions, and the sequence of the CP gene, we conclude that the virus isolated from H. rosa-sinensis in China is Tomato mosaic virus(ToMV). References: (1) S. Adkins et al. Plant Dis. 87:1190, 2003. (2) M. H. V. van Regenmortel et al., eds. Virus Taxonomy. 7th Report of the ICTV, Academic Press, NY, 2000.
Borage (Borago officinalis) is a New Host of Pseudomonas cichorii in the Ebro Valley of Spain
Authors: Cambra M. A. , Palacio-Bielsa A. , López M. M. 
Published: May 2007

Borage (Borago officinalis L.) is an important vegetable crop for consumption in the Ebro Valley of northeastern Spain. During the autumn and spring of the last 10 years, black necrotic lesions were observed in leaf petioles of white-flowered borage plants in greenhouses and seedbeds in Zaragoza, Spain. These lesions developed from the soil line and spread upward to the central vein of leaves. Severely infected leaves of mature and occasionally young plants become rotted. Longitudinal sections through the crown revealed severely necrotic cortical, vascular, and pith tissues. Isolations from infected roots, petioles, and leaves onto King's B medium yielded a gram-negative, rod-shaped bacterium with colonies that were fluorescent under UV light. Bacterial colonies were purified and characterized. The isolates were strictly aerobic, negative for levan production, soft rot of potato, and arginine dihydrolase activity, oxidase positive, and induced hypersensitive reaction in tobacco leaves (2). The bacteria were further identified as Pseudomonas cichorii by comparison of the 49 carbohydrate utilization profiles, API 50 CH (bioMérieux, Marcy l'Etoile, France), with the reference strain ICPPB 2827. Ten lettuce plants used as indicators and borage plants were inoculated by root and petiole injections of bacterial suspensions (108 CFU/ml) of the borage strains and the P. cichorii reference strain ICPPB 2827. Inoculated plants and controls were maintained in a growth chamber at 20 to 25°C with nearly 100% relative humidity. Symptoms of varnish spot, described in lettuce (1), and the black lesions initially observed in borage roots, petioles, and leaves were evident on all inoculated plants at 7 and 5 days after inoculation, respectively. No symptoms developed on control plants. A bacterium with identical characteristics to those described above was reisolated from the black lesions on inoculated plants. To our knowledge, this is the first report of P. cichorii as a pathogen of B. officinalis. Successful infection of borage plants was dependent on high humidity conditions, which is present because of the greater density of mature crops. References: (1) R. G. Grogan et al. Phytopathology 67:957, 1977. (2) R. A. Lelliot et al. J. Appl. Bacteriol. 29:470, 1966.
Southern Blight of Jerusalem Artichoke Caused by Sclerotium rolfsii in California
Authors: Koike S. T. 
Published: May 2007

Jerusalem artichoke or sunchoke (Helianthus tuberosus) is a specialty vegetable that is grown commercially in California. The fleshy tubers are harvested and used as a fresh salad ingredient or cooked vegetable. During 2003, field plantings of Jerusalem artichoke in coastal California (Santa Cruz County) showed symptoms of an unfamiliar disease. Initial symptoms consisted of wilting of new shoots and leaves followed by browning and collapse of all foliage. Crown and lower stem tissues turned tan to brown. In advanced stages of the disease, crown and stem tissues were colonized internally and externally by white, cottony mycelium. Tan, spherical sclerotia that measured approximately 1 mm in diameter formed on the surfaces of the affected crowns and stems. Mycelia and sclerotia also grew on the soil adjacent to infected plants. Isolations from symptomatic crowns, mycelia, and sclerotia produced colonies that were identified as Sclerotium rolfsii. Pathogenicity was tested using two methods that included sclerotial inocula collected from five isolates grown on potato dextrose agar plates. With the first method, sclerotia of each isolate were applied to sets of tubers (10 tubers per isolate) prior to planting tubers into a soilless, peat moss-based medium in pots. With the second method, 3-week-old potted plants were inoculated by placing sclerotia of each isolate adjacent to stem tissue that was 3 cm below the surface of the soilless medium. Noninoculated controls were included for both methods. All plants were incubated in a greenhouse at 21 to 24°C. For the first method, by the third week after planting, 10 to 40% of plants did not emerge because the tubers were rotted and decayed. For the plants that did emerge, wilting of foliage and browning of crown and stem tissue occurred approximately 6 weeks after planting and by 10 weeks, all plants were diseased. S. rolfsii was reisolated from all necrotic tuber, crown, and stem tissues. For the second method, disease symptoms and signs of the pathogen occurred 5 weeks after inoculation and by week 10, 75% of test plants were symptomatic. S. rolfsii was again reisolated from all necrotic tuber, crown, and stem tissues. Symptoms were not observed on any of the noninoculated plants. To my knowledge, this is the first report of southern blight of Jerusalem artichoke in California. This disease has been reported on Jerusalem artichoke in several southern U.S. states (1,2). The two inoculation methods demonstrated that the pathogen could infect propagation organs (tubers) and also emergent stems of this host. References: (1) D. F. Farr et al. Fungi on Plants and Plant Products in the United States. The American Phytopathological Society, St. Paul, MN, 1989. (2) S. M. McCarter and S. J. Kays. Plant Dis. 68:299, 1984.