bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of Cucumber mosaic virus in Viola hederacea in France and Italy
Authors: Cardin L. , Moury B. 
Published: May 2007

Viola hederacea Labill. (Australian violet or trailing violet), family Violaceae, is native to eastern Australia and used for its ornamental quality in humid conditions, especially in terrariums. Mosaic and chlorotic ringspots associated with a mild crinkling on leaves of V. hederacea were observed in gardens in southeast France and La Mortola, Italy in 2001 and 2003, respectively. These symptoms were different from the small chlorotic spots reported in the same species in Queensland, Australia, from which a rhabdovirus was isolated (1). In samples collected from both locations, presence of Cucumber mosaic virus (CMV) was suspected on the basis of the symptoms exhibited by a range of inoculated plants (2) and the observation of isometric particles of approximately 30 nm with the electron microscope in sap preparations. This was confirmed by positive reactions with CMV polyclonal antiserum (3) in double-antibody sandwich-ELISA. Because of the viscosity of the V. hederacea extracts, 0.01% (w/v) of pectolyase in phosphate buffer was used to grind the samples and the homogenate was kept at room temperature for 2 h. In double-immunodiffusion analysis, each isolate was shown to belong to the group II of CMV. Tomato strains D and To were used as positive controls for CMV groups I and II, respectively. The virus was transmitted by aphids (Myzus persicae) in a nonpersistent manner from infected Nicotiana tabacum cv. Xanthi-nc plants to healthy Xanthi-nc plants. To determine if CMV was responsible for the symptoms observed, the French and Italian isolates were multiplied in Xanthi-nc tobacco plants after isolation from local lesions on Vigna unguiculata and mechanically inoculated to 10 plants of V. hederacea. A systemic vein clearing developed on leaves 10 days after inoculation, followed by mosaic and crinkling. CMV was detected in each plant 3 weeks after inoculation. To our knowledge, this is the first report of CMV in V. hederacea in France and Italy. References: (1) D. H. Gowanlock and R. G. Dietzgen. Australas. Plant Pathol. 24:215, 1995. (2) L. Cardin et al. Plant Dis. 87:200, 2003. (3) J.-C. Devergne et al. Ann. Phytopathol. 10:233, 1978.
First Report of Powdery Mildew of Parsley Caused by Erysiphe heraclei in Florida
Authors: Raid R. , Miller C. , Pernezny K. 
Published: May 2007

Parsley (Petroselinum crispum (Mill.) Nym. ex A.W. Hill) is an important leaf crop in the Everglades Agricultural Area of southern Florida. During the spring of 2005 and 2006, disease signs and symptoms resembling those incited by powdery mildew were observed on parsley at a commercial vegetable farm located 15 km east of Belle Glade. Symptoms consisted of leaf chlorosis, particularly in the dense lower canopy, and desiccation of affected tissue. A dense, white-to-light gray fungal growth was visible macroscopically on the surface of affected leaf tissue. Microscopic examinations revealed ectophytic hyphae with lobed appressoria and hyaline, straight conidiophores bearing single conidia. Conidia were short-cylindrical to cylindrical, measured 33 to 44 μm long and 13 to 16 μm wide, and lacked fibrosin bodies. Conidiophore foot cells were also cylindrical, straight, and measured 27 to 37 × 9 to 10 μm. Ascocarps of the teleomorph were not observed. The fungus closely matched the description of Erysiphe heraclei DC, a pathogen previously reported as attacking parsley on the U.S. West Coast (1,2). Pathogenicity was verified by inoculating adaxial leaf surfaces of 12 plants (cv. Dark Green Italian) with conidia collected from infected tissue by using a small brush. Inoculated plants and 12 noninoculated plants were lightly misted, held in a moist chamber for 48 h (22°C), and then incubated in a growth chamber for 4 weeks at 22°C with a photoperiod of 16 h. Symptoms that developed on inoculated plants were similar to those observed in the field, with no symptoms evident on the controls treated in a similar manner. To our knowledge, this is the first report of powdery mildew on parsley in Florida, even though parsley has been grown in the area for at least six decades. Noted as being somewhat unique among fungal pathogens because it favors dry rather than moist climatic conditions, it is probably no coincidence that powdery mildew was observed both years during the month of April, the height of Florida's dry season. The fact that monthly rainfall totals of 22 and 35 mm were recorded during April of 2004 and 2005, respectfully, well below the historical average of 72 mm, may have been a contributing influence. Glawe et al. (1), in issuing a first report of E. heraclei on carrots and parsley in the state of Washington and observing ascocarps on carrot tissue, mentioned the prospect of contaminated seed serving as a potential source of dissemination. Although they did not observe the teleomorph on parsley, prospects for its occurrence seem likely. With the bulk of parsley seed planted in Florida being produced in Washington, Oregon, or California, the observations reported herein may provide credence to such a hypothesis. References: (1) D. A. Glawe et al. Online publication. doi:10.1094/PHP-2005-0114-01-HN. Plant Health Progress, 2005. (2) S. T. Koike and G. S. Saenz. Plant Dis. 78:1219, 1994.
First Report of the Root-Rot Pathogen, Armillaria nabsnona, from Hawaii
Authors: Hanna J. W. , Klopfenstein N. B. , Kim M.-S. 
Published: May 2007

The genus Armillaria (2) and Armillaria mellea sensu lato (3) have been reported previously from Hawaii. However, Armillaria species in Hawaii have not been previously identified by DNA sequences, compatibility tests, or other methods that distinguish currently recognized taxa. In August 2005, Armillaria rhizomorphs and mycelial bark fans were collected from two locations on the island of Hawaii. Stands in which isolates were collected showed moderate to heavy tree mortality and mycelial bark fans. Pairing tests (4) to determine vegetative compatibility groups revealed three Armillaria genets (HI-1, HI-7, and HI-9). Rhizomorphs of genet HI-1 were collected from both dead and healthy mature trees of the native 'Ohia Lehua (Metrosideros polymorpha) approximately 27 km west of Hilo, HI (approximately 19°40′49″N, 155°19′24″W, elevation 1,450 m). Rhizomorphs of HI-7 and HI-9 were collected, respectively, from dead/declining, mature, introduced Nepalese alder (Alnus nepalensis) and from an apparently healthy, mature, introduced Chinese banyan (Ficus microcarpa) in the Waipi'o Valley (approximately 20°03′29″N, 155°37′35″W, elevation 925 m). On the basis of somatic pairing tests and intergenic spacer-1 (IGS-1) nucleotide sequence identities of 99 to 100% with North American A. nabsnona (GenBank Accession No. AY509178), HI-1 (GenBank Accession No. DQ995356), HI-7 (GenBank Accession No. DQ995358), and HI-9 (GenBank Accession No. DQ995359) were identified as A. nabsnona, a pathogen of hardwoods (1). The IGS-1 sequences of A. nabsnona genets (HI-1, HI-7, and HI-9) had a greater similarity to North American collections of A. nabsnona than to the Asian A. nabsnona, even though the two introduced hosts originated from Asia. Phylogeographic studies could help determine the potential introduction and original source of A. nabsnona in Hawaii. Although A. nabsona was isolated from multiple hosts in declining stands, pathogenicity studies are needed to confirm whether this pathogen causes disease on diverse native and exotic tree species in Hawaii. References: (1) E. Allen et al. Pages 2–7 in: Common Tree Diseases of British Columbia. Natural Resources Canada. Canadian Forest Service, Victoria, BC, Canada, 1998. (2) D. E. Hemmes and D. E. Desjardin. Pages 129 and 153 in: Mushrooms of Hawaii. Ten Speed Press, Berkeley, CA, 2002. (3) F. F. Laemmlen and R. V. Bega. Plant Dis. Rep. 58:102, 1974. (4) Y. Wu et al. USDA Forest Service Tech. Rep. R2-58, 1996.
Canavirgella banfieldii Needlecast of Pinus strobus in Michigan
Authors: Merrill W. , Wenner N. G. , O'Donnell J. 
Published: May 2007

In the winter of 1995 to 1996, browning and dieback of the 1995 needle complement of Pinus strobus L., resembling needlecast caused by Canavirgella banfieldii Merrill et al. (1), was observed in Antrim County, MI. (Needle dieback = distal portions of the needles die, but short basal segments remain living and diseased needles remain attached until normal shedding of the entire complement.) Affected needles at that time had not developed ascomata, but bore spent pycnidia resembling those of C. banfieldii. About 25% of the symptomatic needles collected on 7 June 1996 bore hysterothecia of C. banfieldii in various stages of development. On wetting about 8% of these opened and released mature ascospores. Voucher specimens are in BPI and PACMA. Heretofore, C. banfieldii has been known from western North Carolina to central New York, northern Vermont, and central and eastern Maine. This is the first report of this pathogen in the Lake States, a significant extension of its known distribution, and substantiates in part our belief that this long-overlooked fungus probably occurs throughout the natural range of P. strobus. Reference: (1) W. Merrill et al. Can. J. Bot. 74:1476, 1996.
First Report of Nematostoma artemisiae on Artemisia in the United States
Authors: Rossman A. Y. , Taylor N. J. 
Published: May 2007

A fungus associated with leaf hairs of Silver King also known as Silver Wormwood (Artemisia ludoviciana Nutt. subsp. albula (Wooton) Keck) from Missouri (Crawford County, near Bourbon) was identified as the loculoascomycete Nematostoma artemisiae Syd. and P. Syd. When the fungus is present, the leaf hairs become discolored due to the numerous dark ascocarps and eventually drop off and the living leaves lose their silvery appearance, detracting from the ornamental value of the plants. Undocumented observations suggest that the fungus occurred on this host in Ohio and other states of the Midwest in 1995. N. artemisiae was described from Japan on Artemisia indica Willd. and reported once from China on that host. The type specimen was recently redescribed and illustrated by Sivanesan (1) who provided an account of the genus of which this is the type species. The uniloculate fruiting bodies of N. artemisiae are solitary, superficial to basally immersed, dark brown, globose, 120 to 160 μm in diameter, with four to 10 black setae 125 to 175 (300) μm long extending from the thickened region around the ostiole. The bitunicate, cylindrical, 8-spored asci are 50 to 65 × 7 to 9 μm and contain pale brown, broadly fusiform, smooth ascospores, 14 to 18 × 4.5 to 5.0 μm, three-septate, slightly constricted at each septum. The anamorph pycnidia are similar in appearance to the ascomycete fruiting bodies and contain hyaline, broadly spherical conidia 3 to 5 μm in diameter. The specimen has been deposited at the U.S. National Fungus Collection (BPI 749199). Reference: (1) A. Sivanesan. Syst. Ascomycetum 6:201, 1987.
A Disease of Pearl Millet in Zimbabwe Caused by Pantoea agglomerans
Authors: Frederickson D. E. , Monyo E. S. , King S. B. , Odvody G. N. 
Published: May 2007

Necrosis at the leaf tips and margins of pearl millet (Pennisetum glaucum (L.) R. Br.) was observed in 1995 in a Pseudomonas syringae resistance screening nursery near Bulawayo, Zimbabwe. Straw-colored lesions with a chlorotic edge often extended the leaf length, and were atypical of the round spots, with a brown margin, caused by P. syringae (1). Bacteria were isolated from cut lesions macerated in water by dilution streaking onto King's medium B and nutrient agar. A gram-negative, nonfluorescent, fermentative, rod-shaped bacterium, forming yellow colonies on nutrient agar was consistently observed. Three pots of 10, 2-to 3-week-old seedlings of a susceptible cultivar, 852B, were inoculated with a 108 CFU per ml suspension from cultures by misting or injection into the whorl. In three experiments, the treatment and uninoculated control were incubated at 25°C and 95% relative humidity for 48 h before transfer to the greenhouse. The original symptoms of watersoaking at leaf tips and margins were observed after 4 days. Necrotic lesions surrounded by chlorotic tissue were observed a day later. Fluorescence on King's medium B, and levan, oxidase, potato-rot, arginine dihydrolase, 2-keto gluconate, nitrate reduction, gelatin, phenylalanine deaminase, and acid from starch tests were negative. Tobacco hypersensitivity, acid from sucrose and glycerol, aesculin hydrolysis, lipase, indole production, and growth on tetrazolium chloride were positive. The identification of the pathogen to the species level as Pantoea agglomerans (Ewing and Fife 1972) Gavini et al. 1989, formerly Erwinia herbicola, was by fatty acid analysis by the International Mycological Institute (Egham, Surrey, UK). P. agglomerans was recorded as a pathogen of pearl millet in India in 1958 (2). References: (1) G. N. Odvody and A. K. Vidaver. Sorghum Newsl. 23:134, 1980. (2) C. K. S. Rajagopalan and G. Rangaswami. Curr. Sci. 27:30, 1958.
New Hosts of Potato Y Potyvirus (PVY) Identified in the Canary Islands
Authors: Espino de Paz A. I. , Mendez Pérez P. , Jordá-Gutiérrez C. 
Published: May 2007

Potato Y potyvirus (PVY) causes annual epidemics with 30 to 40% production losses in tomato crops of the Canary Islands in autumn. Two strains of the virus were diagnosed: PVY-0 and PVY-N. To identify hosts in areas where the virus is prevalent, and to establish the role of weeds in the epidemiology of this virus and its vector, plants were collected, chosen randomly and by viruslike symptom expression. Eighty-two samples of 30 plant species were tested for PVY-0 and PVY-N by double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) with commercial antibodies made against PVY (INGENASA, Madrid), PVY-0/C (ADGEN, Auchincruive, UK), and PVY-N (BIOREBA, Reinach, Switzerland). Twenty-five weed species were found to be infected with PVY-0 and 12 plants were identified as new hosts (1) including the following: Argyranthemum gracile, Calendula arvensis, Convolvulus althaeoides, Foeniculum vulgare, Forsskaolea angustifolia, Hedypnois cretica, Hirschfeldia incana, Malva parviflora, Patellifolia patellaris, Sonchus oleraceus, Urospermum picroides, and Lavandula canariensis. Argyranthemum gracile and Lavandula canariensis were hosts only of PVY-N strain. References: (1) J. R. Edwarson. Fla. Agric. Exp. Stn. Monog. 5:96, 1974.
First Report of Erwinia amylovora on Crataegus monogyna and Pyrus pyraster in Bulgaria
Authors: Bobev S. G. , Crepel C. , Maes M. 
Published: May 2007

Typical symptoms of fire blight, caused by Erwinia amylovora, were observed in late June of 1998 on Crataegus monogyna Jacq. (hawthorn) and Pyrus pyraster Burgsd. (syn. P. caucasia, wild or thorny pear) in the region of Plovdiv. Symptoms observed on hawthorn were shepherd's-crook shoots, necrotic flowers and fruitlets, and dried amber ooze droplets. On thorny pear, only infected shoots were detected. Isolation on King's B medium (2 days, 26°C) resulted in the appearance of whitish, glistening, rounded colonies. Based on their cultural characteristics, positive hypersensitive response (HR) on tobacco leaves, successful laboratory inoculations of hosts' shoots and pear fruitlets, positive serological reaction (slide agglutination), and target-specific polymerase chain reaction (PCR; 23S rDNA), the isolates from both species were placed in the E. amylovora group. The bacterium has also been isolated by the first author from Cydonia oblonga, Pyrus communis, Mespilus germanica, and Malus sylvestris within the 5-year period of 1989-1993 (1). To our knowledge this is the first official report of fire blight on C. monogyna and P. pyraster in Bulgaria. Reference: (1) S. G. Bobev. 1995. Pages 121–126 in: Jubilee Scientific Session, Higher Agricultural Institute of Plovdiv, vol. 3, bk. 1. (In Bulgarian.)
Powdery Mildew of Field-Grown Tomato in Florida
Authors: Pernezny K. , Sonoda R. M. 
Published: May 2007

Powdery mildew was observed affecting mature, field-grown, fresh-market tomatoes in southeastern Florida (St. Lucie, Martin, Palm Beach, and Broward counties). Outbreaks were noted in May of 1996 and throughout the spring of 1997. Affected leaves were generally yellow and, in some cases, developed a purplish cast. Whitish areas of fungal growth were often seen in the middle of lesions, but were less prominent than that reported for powdery mildew of field tomato in Hungary (2). Microscopic examination revealed that conidia were produced in chains, contained no fibrosin bodies, and were not dimorphic. Conidial measurements were 33.2 × 15.6 μm, based on 21 samples of five conidia taken from five different fields. These measurements were similar to those for an Erysiphe sp. causing powdery mildew of greenhouse tomato in New York (1). Greenhouse-grown tomato plants, cv. Sunny, in the fourth-true-leaf stage were inoculated with conidia scraped from lesions gathered in commercial fields. A single-edged razor blade was used to transfer the fungus to the adaxial surface of the test plants. Powdery mildew symptoms were observed within 10 days of inoculation. Morphology and size of conidia taken from greenhouse plants were similar to those for original field samples. This is the first report of powdery mildew of field-grown tomato in Florida. References: (1) D. M. Karasevicz and T. A. Zitter. Plant Dis. 80:709, 1996. (2) L. Kiss. Plant Dis. 80:224, 1996.
First Report of Downy Mildew (Race 2) of Sunflowers in Italy
Authors: Zazzerini A. , Tosi L. 
Published: May 2007

During a survey in the spring of 1997, sunflower (Helianthus annuus L.) plants with characteristic symptoms (stunting and veinal chlorosis of leaves) of downy mildew caused by Plasmopara helianthi Novot. were observed in two experimental fields in the central Italian region of Umbria. In the first field, used to evaluate 58 commercial sunflower hybrids, fewer than 1% of plants displayed typical downy mildew symptoms. In a second field, planted with the old susceptible cultivar Ala, disease incidence was 12%. The inoculum of P. helianthi (one isolate from each field) was obtained either from downy mildew-infected leaves or infested soil (from around the roots of diseased plants). All were collected according to a random distribution. From this collection, two isolates were identified as race 2 by the whole-seedling immersion technique (2) with differential cultivars: HA 89, AD 66, CM 90 RR, RHA 265, RHA 274, HIR 34, DM-2, and HA 335. All differential lines were tested twice with 30 seeds per replicate (four replicates per line). Two weeks after inoculation the percentage of susceptible seedlings (showing sporulation on cotyledons and/or first true leaves) was determined. Race 2 has long occurred in some European countries, but this is the first report of this race from Italy. Extensive field surveys carried out in the last 10 years revealed that race 1 is the only one occurring in central Italy. An isolate apparently comparable to race 2 was reported in experimental plots in 1975 (1) where only Pl1 cultivars were susceptible. Differential lines, at that time, were not available and race identification was not carried out. Italy imposes importation regulations for sunflower seed that include treatment with metalaxyl. In greenhouse trials we have not observed a reduction in sensitivity to this systemic fungicide used as seed treatment against P. helianthi race 2. Consequently, the susceptibility of some commercial hybrids, indicated as resistant to downy mildew by importers, could be attributed to irregularity in the production of seeds. Also, an insufficient seed dressing with metalaxyl does not completely control the pathogen. References: (1) M. D'Armini et al. Atti Giornate Fitopatol. 1:659, 1975. (2) T. J. Gulya et al. Helia 14:11, 1991.
Southerly Extension of Poplar Leaf Blight (Linospora tetraspora) in the Pacific Northwest
Authors: Newcombe G. 
Published: May 2007

Poplar leaf blight caused by Linospora tetraspora G. E. Thompson (Ascomycetes, Valsaceae) is widespread on Populus balsamifera in Canada from Quebec to British Columbia (1). The only United States records of this northerly fungus are from Vermont, Wisconsin, and Alaska (1,2). There are no records of this fungus on the Pacific Coast south of British Columbia, despite the presence of susceptible hosts (i.e., Populus trichocarpa and its hybrids). However, in September of 1997, the disease was observed in a hybrid poplar plantation at latitude 47.9°N and longitude 122.1°W near Snohomish, Washington. Blight affected the lower crown of trees in their second year of growth. Leaf lesions, with their characteristic black stromata, were easily distinguished from symptoms of other diseases. Some individual lesions of L. tetraspora affected entire leaf laminae, but there appeared to be little premature defoliation at the time of observation. Populus trichocarpa × P. deltoides hybrids were more commonly blighted than were P. trichocarpa × P. maximowiczii hybrids (i.e., 13/18 clones affected versus 4/11, respectively). A voucher specimen was deposited in the Herbarium at the Pacific Forestry Centre (DAVFP 25289). References: (1) M. E. Barr. Mycol. Mem. No. 7:130, 1978. (2) D. F. Farr. et al. 1989. Fungi on Plants and Plant Products in the United States. American Phytopathological Society, St. Paul, MN.
First Report of Cassava Common Mosaic Potexvirus Infecting Chaya (Cnidoscolus chayamansa) in Tuvalu
Authors: Jones P. , Devonshire J. , Dabek A. , Howells C. 
Published: May 2007

Chaya (Cnidoscolus chayamansa McVaugh) was introduced into Tu-valu as a leaf vegetable in the early 1990s (1) with the primary objective of alleviating vitamin A and C deficiencies, which at that time were prevalent throughout the population. Although there are no definitive quarantine records, we believe that the crop originated from vegetative cuttings introduced into Funafuti atoll from Kiribati. In the years following its introduction, chaya was distributed as cuttings taken from the original, introduced germplasm, to other islands and atolls of Tuvalu. The occurrence of yellow patches on the mature leaves of chaya cultivated in Funafuti had previously been attributed to iron deficiency, which was the inevitable consequence of growing the crop on coral atoll soils that are well known to be poor sources of metallic ions, notably iron, zinc, and copper. Following heavy cyclonic rains in March 1997, young, emerging chaya leaves were noted to exhibit an angular mosaic of the leaf lamina, characteristic of virus infections. Negatively stained sap from mosaic-affected leaves, when examined in the transmission electron microscope, was found to contain many rod-shaped virus particles similar in morphology to those of the Potexviridae (approximately 510 × 15 nm). The virus was transmitted mechanically to Chenopodium amaranticolor, in which it induced local lesion symptoms. The virus was found to be more closely related serologically to cassava common mosaic potexvirus (CsCMV) from Brazil than to that from Colombia, by immunosorbent electron microscopy with antisera kindly provided by F. Morales. Recently, CsCMV particles have been found in mosaic-affected chaya derived from the original Funafuti mother plants on Vaitupu Island. Similar symptoms have been observed on chaya being cultivated in Nui and Nanumaga islands. We conclude that CsCMV must now have been distributed throughout the atolls and islands of Tuvalu by infected planting material. We believe this to be the first report of the occurrence of CsCMV outside Central America and the first record of a plant virus from Tuvalu. Reference: (1) C. Howells and M. Bainbridge. 1996. South Pacific Commission, Pacific Island Forests and Trees. Page 10.