bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of Flag Smut of Wheat Caused by Urocystis agropyri in the United Kingdom
Authors: Sansford C. E. , Beales P. A. , Clarkson J. D. S. 
Published: May 2007

An isolated occurrence of flag smut of wheat, caused by Urocystis agropyri (G. Preuss) J. Schröt., was confirmed in the county of Essex, UK, in autumn-sown winter wheat (Triticum aestivum L.) cv. Riband grown from certified seed. The origin of the infection is unknown. Symptoms were first observed on 22 May 1998. The presence of U. agropyri was confirmed on the basis of the macroscopic symptoms on the host and the morphology of the pathogen (2). Long gray-black streaks parallel with the veins were observed on leaf blades, especially the flag leaf, and on leaf sheaths. The streaks consisted of lines of fungal sori developing between the leaf veins, giving a striped appearance. Eruption of the sori through the epidermis of the leaves had caused them to fray, exposing dark brown to black powdery spore masses. Microscopic examination revealed spore balls measuring 20 to 28 μm in diameter containing 1 to 3 spores per ball. Spores were dark brown measuring 12 to 17.5 μm in diameter and were surrounded by light brown sterile cells measuring 7 to 7.5 μm. Affected plants were stunted to about half the height of healthy plants. Some affected plants tillered excessively and in some cases the ear failed to emerge from the boot. Some diseased leaves were twisted and, where the host epidermis had ruptured to expose the spore masses, the affected parts had the appearance of being covered in black soot. All of the symptoms are typical of flag smut on wheat. Flag smut has been observed on grasses in every continent except Antartica. However, the distribution of the pathogen on wheat is more limited. Flag smut of wheat is known to occur in at least some of the countries of the European Union as well as (e.g.) the USA and Australia. This finding is significant because it had been considered that U. agropyri on wheat had reached the limits of its ecoclimatic zone, since it requires specific environmental conditions for infection and disease development, particularly a mild winter and an arid summer (1). The climatic conditions in Essex between September 1997 when the affected crop was planted and May 1998 when symptoms were first observed were considerably drier and warmer than normal, thus favoring the pathogen. This is the first report of U. agropyri on wheat in the UK. References: (1) R. F. Line. 1998. Pages 49–60 in: Bunts and Smuts of Wheat: An International Symposium. No. Am. Plant Prot. Org., Ottawa. (2) J. E. M. Mordue and J. M. Waller. 1981. Urocystis agropyri. CMI Descriptions of Pathogenic Fungi and Bacteria, No. 716. Kew, England.
Lilac Witches'-Broom in North Dakota
Authors: Walla J. A. , Guo Y. H. 
Published: May 2007

Lilac witches'-broom (LWB), caused by the ash yellows (AshY) phytoplasma, was identified in common lilac (Syringa vulgaris L.) in Cass and Ransom counties in southeast North Dakota in 1997 and 1998. The infected plants were immature, naturally regenerating lilac in the understory of three 57- and 58-year-old Prairie States Forestry Project windbreaks that have lilac as a planted component. In late summer and early fall of 1997, the terminal ends of hardened-off, current-season shoots on more than 100 immature plants were dead, and two to three succulent, late-season shoots were present just below the dead tips. Succulent shoots collected from one such plant in each of two of the windbreaks (both in Ransom Co.) were positive for the AshY phytoplasma, using immunofluorescence (IF) with an AshY phytoplasma-specific monoclonal antibody (1). One of those shoots was also positive with a universal phytoplasma-specific primer pair (R16F2/R2) (2) in a polymerase chain reaction (PCR). Succulent shoots from a plant in the third windbreak (in Cass Co.) were IF negative. In late spring of 1998, more than 100 young plants in two of the same windbreaks (one each in Cass and Ransom counties) had abnormal shoot growth, including combinations of yellow, distorted leaves, multiple shoots, and twig dieback. A shoot from one of two plants sampled in the Ransom Co. windbreak was IF positive. Roots from two of four plants sampled in the Cass Co. windbreak were IF positive, while the other root samples and shoot samples from the same four plants were IF negative. A shoot from one of the IF positive plants was positive for phytoplasmas in a PCR. Witches'-brooms were not observed in the planted lilacs. This is the first report of LWB in North Dakota and in the Great Plains region of North America. While the AshY phytoplasma is known in green ash (Fraxinus pennsylvanica Marsh.) in the Great Plains, this report documents substantial extension of the known range of LWB westward from Wisconsin (3). Lilac is a very important shrub in both rural and urban plantings in the northern Great Plains and is the most commonly planted shrub in North Dakota. With this report, LWB should be considered among the possible damaging agents in lilac in this region. References: (1) Y. H. Guo and T. A. Chen. Phytopathology 83:243, 1993. (2) I.-M. Lee et al. Phytopathology 83:834, 1993. (3) W. A. Sinclair et al. Plant Dis. 80:468, 1996.
First Report of a Closterovirus-Like Particle Associated with Pineapple Plants (Ananas comosus cv. Smooth Cayenne) Affected with Pineapple Mealybug Wilt in Cuba
Authors: Borroto Eduviges G. , Cintra Mayra , González Justo , Borroto Carlos , Oramas Pedro 
Published: May 2007

Pineapple mealybug wilt (PMW) was first described in Hawaii in 1910 and has since spread wherever pineapple is cultivated. PMW is currently one of the most important field diseases of pineapple in Cuba, causing up to 40% crop loss. Leaves of plants affected with PMW turn bronze-red and lose turgidity, and the tips curve down. Root system size is decreased and fruits are unmarketable because the flesh is fibrous and sour. Leaves from wilt-affected pineapple plants were selected from the Experimental Station “Tomás Roig” at Ciego de Avila, Cuba. Asymptomatic plants derived from meristem tissue and cultivated under greenhouse conditions were also collected. Both samples were analyzed by several virus purification procedures and finally purified with a protocol modified from Gunashinge and German (1). Partially purified samples from symptomatic and asymptomatic plants were negatively stained and examined by a JEOL (JEM-2000 EX) transmission electron microscope at a magnification of ×30,000. Sixteen, long, flexuous, rod-shaped, viruslike particles (estimated length 1,200 to 1,450 nm; width about 12 nm) were observed in symptomatic leaves, using electron microscope micrographs. These particles were similar to those of the pineapple clostero-like virus found in Hawaii (1) and Australia (2). Particles were observed from symptomatic plants but not from plants propagated by primary meristem culture. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of viral proteins indicated that the coat protein has a molecular mass of approximately 23 kDa. This is the first report of closterovirus-like particles associated with pineapple plants (Ananas comosus cv. Smooth Cayenne) affected with PMW in Cuba. References: (1) U. B. Gunasinge and T. L. German. Phytopathology 79:1337, 1989. (2) W. Wakman et al. Aust. J. Agric. Res. 46:947, 1995.
Occurrence of Potato Tuber Necrotic Ringspot Disease (PTNRD) in Italy
Authors: Tomassoli L. , Lumia V. , Cerato C. , Ghedini R. 
Published: May 2007

Potato tuber necrotic ringspot disease, caused by a tuber necrotic isolate of potato virus YN named PVYNTN, was originally described in Hungary in 1980; later on, the disease spread throughout northern and eastern Europe (1). Recently, the virus was reported in Portugal (2) on fresh-market potatoes. During the summer of 1997, the disease appeared in the north of Italy, causing serious damage in processing and fresh-market potatoes. After harvesting, we observed in most of the potato cultivars tubers showing the typical superficial necrotic rings and areas. These viral lesions were predisposed to secondary infection by fungi and bacteria. Moreover, PVYNTN causes degradation of tuber starch into simple carbohydrates. This metabolic activity resulted in undesirable browning in chips. In different areas of northern Italy, samples were collected from 48 stocks of cv. Hermes, the most important processing cultivar in Italy, and from 12 stocks of other potato cultivars (Ernterstolz, Liseta, Monalisa, Primura, Kennebec). The original seed of the stocks came from five different European countries: Austria, Italy, Scotland, Switzerland, and The Netherlands. Samples were serologically tested by indirect enzyme-linked immunosorbent assay with specific monoclonal antibodies to tobacco venial necrosis strain group of PVY. The results showed that 37 out of 60 analyzed stocks were infected by an isolate belonging to PVYN group, 7 stocks were infected by a common isolate of PVY, and 16 were PVY free. To distinguish the tuber-necrosis isolate (PVYNTN) from the PVYN isolates, reverse transcription-polymerase chain reaction (RT-PCR) and immunocapture-RT-PCR were carried out with specific primers for PVYNTN (3). Both tuber and leaf sap were tested. RT-PCR was performed on tuber sap and immunocapture-RT-PCR on leaf sap. Leaf and tuber sap of healthy, PVY-infected, and PVYNTN-infected tobacco was used in each experiment. At least two tubers from each of 32 PVYN-infected stocks were included in the molecular assay. All samples showed an amplified product of the characteristic size for PVYNTN (835 bp), whereas neither the healthy control nor the PVY sample gave a product. All tested cultivars were infected and all countries from which tuber seed came revealed infected stocks. The high proportion of samples in which PVYNTN was detected suggests that the virus is now endemic to potato-growing regions of northern Italy. The weather in these regions during 1997 was mild and drought in winter-spring and very warm in late summer; these conditions were ideal for disease diffusion by vectors and for symptom development. This is the first report of the occurrence of PVYNTN in Italy. References: (1) C. Kerlan. Le Pomme de Terre Française 498:40, 1997. (2) M. C. Serra and H. L. Weidemann. Plant Dis. 81:694, 1997. (3) H. L. Weidemann and E. Maiss. Z. Pflanzenkrank. Pflanzenschutz 103:337, 1996.
Reoccurrence of Rose Bloom Caused by Exobasidium oxycocci in Cranberry in Massachusetts
Authors: Caruso F. L. 
Published: May 2007

Cranberry (Vaccinium macrocarpon Ait.) vines (cv. Howes) from a commercial cranberry bed on Nantucket Island displayed typical symptoms of rose bloom disease in June, 1997. The affected area (1.5 × 30.0 m) consisted of less than 1% symptomatic uprights and was not covered by sprinkler heads of the chemigation system. The same area that did not receive insecticides or fungicides was damaged by black-headed fireworm (Rhopobota naevana) feeding during the 1996 growing season. The surface of the leaves on the abnormal branches displayed the typical white, powdery external appearance, which consisted of basidia and basidiospores of the pathogen Exobasidium oxycocci Rostr. ex Shear that were hyaline, fusiform with a slight curvature, and measured 14 to 18 × 2 to 3 μm, matching a previous description (2). Plants showing symptoms had been infected during 1996. Abnormal lateral shoots with swollen pink leaves grew from infected axillary buds on the previous year's wood (3). Cranberry plants were inoculated with basidiospores but symptoms may take longer than 1 year to develop. Rose bloom was formerly a common disease affecting cranberry in Massachusetts and control strategies were addressed in the disease management recommendations sent out by the Cranberry Experiment Station to growers through 1954. Bergman (1) reported that the disease was found almost every year before 1945, but since then there were no serious outbreaks, possibly due to changes in cultural practices. The fungicide ferbam (ferric dithiocarbamate) largely replaced Bordeaux mixture as a fungicide to combat fruit rot in the late 1940s. The disease was not brought in with imported vines from the Pacific Northwest, where the disease is common, because the vines in this bed were planted in 1910. The disease has not been observed in either wild or abandoned cranberry beds that have not received fungicide applications. This is the first report of this disease in Massachusetts in nearly 50 years. References: (1) H. F. Bergman. 1953. Yearbook of Agriculture, p. 792. (2) F. L. Caruso and D. C. Ramsdell, eds. 1995. Compendium of Blueberry and Cranberry Diseases. American Phytopathological Society, St. Paul, MN. (3) C. L. Shear et al. 1931. U.S. Dep. Agric. Tech. Bull. 258.
First Report of Black-Foot Disease, Caused by Cylindrocarpon obtusisporum, of Grapevine in California
Authors: Scheck H. J. , Vasquez S. J. , Gubler W. D. , Fogle D. 
Published: May 2007

Black-foot disease, caused by Cylindrocarpon obtusisporum (Cook & Harkn.) Wollenweb., impacts young table and wine grape (Vitis vinifera) plantings throughout California. Two- to 5-year-old grapevines showed reduced vigor with small-sized trunks, shortened internodes, uneven wood maturity, sparse foliage, and small leaves with interveinal chlorosis and necrosis. In cross-section, trunks showed dark brown to black streaking in a few to most of the vascular elements. Symptoms included a reduction in root biomass and root hairs with sunken, necrotic root lesions. Pith of affected vines was compacted and discolored. Isolations made from roots, vascular elements, and pith tissue consistently yielded colonies of C. obtusisporum as verified by descriptions in standard texts. Koch's postulates were completed by dipping the roots of cv. Carignane seedlings in a 108 spore per ml suspension for 30 min. Plants were repotted in an artificial soil mix and held in a controlled environment facility at 24°C. Typical black-foot symptoms developed on 92% of the plants within 8 weeks. Control plants dipped in distilled water remained healthy. Cylindrocarpon destructans, a species closely related to C. obtusisporum, was first reported to cause “black-foot disease” on young vines in 1961 (2). In 1975, C. obtusisporum was reported to produce similar “black-foot” symptoms (1). We propose the common name Cylindrocarpon black-foot disease be used with both species. References: (1) S. Grasso et al. Vitis 14:36, 1975. (2) D. R. Maluta and P. Larignon. Viticulture 11:71, 1991.
Occurrence of Ergot (Sugary Disease) Incited by a Sphacelia sp. on Sorghum in Mississippi in 1997
Authors: Zummo N. , Gourley L. M. , Trevathan L. E. , Gonzalez M. S. , Dahlberg J. 
Published: May 2007

Ergot (sugary disease) incited by a Sphacelia sp. was observed on Sorghum bicolor (L.) Moench var. Sweet Leaf II at Leland and Pop-larville, MS, in October 1997. The disease was characterized by droplets of a thick, sticky, semi-transparent secretion similar to aphid honeydew. The caryopsis of infected florets was converted to relatively soft, chalky pink, tumescent, immature sclerotia (1.5 to 1.7 × 4 mm) with blunt ends. Abundant conidia (11 to 17 × 5 to 7 μm) were produced on stromatic tissue and in large numbers in the sugary secretion. This fungus is similar to that described by Zummo in West Africa (2). Velazquez-Valle et al. (1) recently reported the distribution of Claviceps africana Frederiksen, Mantle & de Milliano in the United States in 1997. The Sphacelia stage of the fungus found in Mississippi is similar to that reported from other areas of the U.S. Our report extends the range for this fungus, which is contiguous to those areas reported by Velazquez-Valle et al. (1). References: (1) R. Velazquez-Valle et al. 37th Annu. Mtg. Carib. Div., Am. Phytopa-thol. Soc., San Jose, Costa Rica, No. 77, 1997. (2) N. Zummo. 1984. Sorghum Diseases in West Africa. An Illustrated Text. USDA/USAID, Zaria, Nigeria.
Purple Blotch, Caused by Alternaria porri, on Leek Transplants in California
Authors: Koike S. T. , Henderson D. H. 
Published: May 2007

In 1997, a foliar disease was detected on leek (Allium porrum) grown as transplants in California greenhouses. Initial symptoms consisted of small (less than 5 mm in diameter), circular, white leaf spots. Spots later enlarged, and became elliptical to oblong in shape and purple with tan borders in color. When spots coalesced, the leaf tips desiccated and wilted. Singly borne, brown conidia from leaves were obclavate in shape with slender, unbranched beaks extending from the narrow end of the spore body. Spore body dimensions measured 81 to 120 (96 mean) µm × 14 to 19 (16 mean) µm, and beaks measured 11 to 56 (30 mean) µm × 3 to 6 (4 mean) µm. Spore bodies had 6 to 9 transverse septa and occasionally 1 longitudinal septum. The fungus was identified as Alternaria porri (Ellis) Cif. (1). The same fungus was also consistently isolated from the margins of the spots. For pathogenicity tests, isolates were grown for 6 weeks on potato dextrose agar under a combination of one cool white and one Vita-Lite fluorescent tube on a 12 h light/dark cycle. Conidial suspensions (1.0 × 10 e 4 conidia/ml) were sprayed onto 2-month-old leek (cvs. Broad London and Gavilan). Plants were incubated in a moist chamber for 48 h and then kept in a greenhouse. After 14 days, leaf spots similar to the original symptoms developed on inoculated plants, and the pathogen was reisolated. Control plants sprayed with distilled water remained symptomless. The experiment was repeated and the results were similar. The isolates also caused leaf spots on onion (Allium cepa cv. Stockton Early Yellow) and chives (Allium schoenoprasum). This is the first report of purple blotch caused by A. porri on commercially grown leeks in California. The occurrence of this disease on leeks in enclosed greenhouses strongly suggested that the primary inoculum was seed-borne. Reference: (1) M. B. Ellis and P. Holliday. C.M.I. Descriptions No. 248, 1970.
First Report of St. John's-Wort Anthracnose Caused by Colletotrichum gloeosporioides in Hungary
Authors: Schwarczinger I. , Vajna L. 
Published: May 2007

In 1997, we observed high incidence of severe disease symptoms in a plantation of St. John's-wort (Hypericum perforatum L.) that has been cultivated as a medicinal plant in Hungary. Symptoms were characterized by brown, 2- to 15-mm-diameter, sunken lesions that girdled the stems and, when occurring near the base, killed the plants. Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. in Penz. was consistently isolated from lesions. Acervuli containing conidia and dark setae emerged from the lesions. Perithecia of the teleomorph Glomerella cingulata (Stoneman) Spauld. & H. Schrenk also appeared on stems. Plants were inoculated with conidial suspension of the fungus (2 × 107/ml), then incubated in a moist chamber for 24 h, and subsequently transferred to the greenhouse. The first symptoms appeared on stems and leaves 7 days after inoculation. Chlorotic spots grew into circular and buff-colored lesions that coalesced and then desiccated. The fungus caused severe defoliation and plant death within 2 weeks. Koch's postulates was completed by consistently reisolating the pathogen from inoculated plants. This disease on St. John's-wort has not previously been reported in Hungary. However, an anthracnose disease caused by Glomerella cingulata (Stoneman) Spauld. & H. Schrenk var. migrans Wollenweber (Gloeosporium orbiculare Berk. & Mont.) was reported in Germany in 1949 (1). Reference: (1) H. W. Wollenweber and H. Hochapfel. Z. Parasitenkd. 14:181, 1949.
First Report of Phytophthora nicotianae Causing Leaf Blight, Fruit Rot, and Root Rot of Papaya in American Samoa
Authors: Roberts P. D. , Trujillo E. 
Published: May 2007

Papaya trees (Carica papaya) were observed in 1997 with symptoms of acute chlorosis and wilting of foliage, circular whitish lesions with necrotic centers on fruits, and root and trunk rots that killed the diseased trees. Identical symptoms were observed on many trees in fields interplanted with other crops and in home gardens on two of the five islands of American Samoa. A Phytophthora sp. was consistently isolated on water agar from symptomatic stems, fruits, and roots. The fungus was grown in pure culture on V8 juice medium at 25°C under continuous fluorescent illumination, and was identified, on the basis of spherical to broadly ovoid (34 to 67 × 40 to 50 µm), intercalary to terminal sporangia, chlamydospores (20 × 40 µm), and uniform to uneven hyphae (5 to 7 µm wide), as Phytophthora nicotianae Breda de Haan (= P. parasitica Dastur) (1,2). Ten 4-week old papaya seedlings grown on pasteurized soil in 15-cm pots were inoculated with a 2-ml suspension of 100 sporangia per ml in sterile water applied to the soil surface. Six uninoculated plants were used as controls. Two mature fruit that had reached the climacteric point were inoculated with 200 µl of sterile water containing approximately 20 sporangia. Inoculum was placed inside a 1-cm-diameter rubber circle that had been attached to the surface of the fruit to prevent run-off. Two uninoculated fruits served as controls. Inoculations of seedlings and fruit were conducted three times. Wilting symptoms developed on inoculated plants in less than 5 days and plant death accompanied by crown rot occurred in 14 days. Inoculated fruit developed lesions covered with a whitish fungal growth within 10 days after inoculation. Plants and fruits exposed to sterile water were healthy. The pathogen was reisolated from the diseased plants and fruits and it was morphologically identical to the original isolate, confirming its role as the causative agent of the disease. The wide distribution of diseased plants over an estimated one-quarter of the area of the island of Tutuila (approximately 24 sq. km) and on the adjacent island of Ofu indicates that the disease was not of recent introduction. References: (1) H. H. Hob et al. The genus Phytophthora in Taiwan. Inst. Bot., Ac. Sinica, Monogr. Ser. 15., 1995. (2) G. M. Waterhouse and J. M. Waterhouse. C.M.I. Descriptions of Pathogenic Fungi and Bacteria No. 34, 1964.