bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of Natural Infection of Luffa acutangula by Watermelon bud necrosis virus in India
Authors: Mandal B. , Jain R. K. , Chaudhary V. , Varma A. 
Published: May 2007

In August 2002, ridge gourd (Luffa acutangula) plant samples exhibiting yellowing of leaves were collected from the experimental farm of Tamil Nadu Agricultural University, Coimbatore, India. Mechanical inoculations of ridge gourd seedlings using the above samples resulted in chlorotic spots on inoculated leaves and vein clearing followed by chlorotic rings and yellow netting along veins of newly developed leaves. The virus was reisolated from the chlorotic spots of the seedlings. Extracts from the field samples as well as mechanically inoculated seedlings reacted with antiserum to Watermelon silver mottle virus (WSMoV) in direct antigen coating enzyme-linked immunosorbent assay, suggesting the association of a tospovirus belonging to WSMoV serogroup (2). Symptomatic leaves from the second mechanical passage exhibiting yellow netting along the veins were subjected to reverse transcription-polymerase chain reaction (1) to identify the genus Tospovirus. Using the primer pair (5′TCTGTCCT(C/T) TTGAA (G/T) GTCCA3′ and 5′AGAGCAATCGAGGCGCT3′) derived from the conserved sequences of Groundnut bud necrosis virus (GBNV) and WSMoV, part of the nucleocapsid (N) protein gene and the complete noncoding region upstream of the N gene's coding sequence were cloned and sequenced. Comparative sequence analysis of 291-bp region of the N gene revealed that the genus Tospovirus infecting ridge gourd shared maximum identity both at nucleotide (94%) and amino acid (97%) levels with the corresponding region of Watermelon bud necrosis virus (WBNV), which is a distinct species of WSMoV serogroup infecting watermelon in India (1). In contrast, only 76 to 81% and 82% identity at nucleotide and amino acid levels, respectively, was observed with the corresponding region of the N genes of GBNV and WSMoV. Natural infection of WBNV in cucurbits except watermelon in India is not known. To our knowledge, this is the first report of natural infection of ridge gourd by WBNV. References: (1) R. K. Jain et al. Arch. Virol. 143:1637, 1998. (2) J. W. Moyer. Tospoviruses (Bunyaviridae). Pages 1803–1807 in: Encyclopedia of Virology. A. Granoff and R. G. Webster, eds. Academic Press, New York, 1999.
First Report of an Elm Yellows Subgroup 16SrV-C Phytoplasma Infecting Grapevine in Serbia
Authors: Duduk B. , Ivanovic M. , Dukic N. , Botti S. , Bertaccini A. 
Published: May 2007

During a 2002 survey in Serbia, samples of grapevine (Vitis vinifera) were collected from plants showing typical phytoplasma-like symptoms: leaf roll, leaf redness, vein chlorosis and necrosis, and absence of lignification. The material was collected from one viticultural region (Zupa Aleksandrovac), where the disease was recorded in 2000 and showed an increasing percentage of symptomatic plants every year. Total nucleic acid was extracted separately from leaf midveins and stem bark collected from 10 symptomatic and 2 asymptomatic plants. Phytoplasma infection was detected using polymerase chain reaction (PCR) assays with universal primer pair P1/P7 for the amplification of phytoplasma 16S rRNA gene, and primer pair FD9f2/FD9r followed by FD9f3/FD9r2 in nested PCR for specific amplification of the FD9 nonribosomal DNA fragment of the EY-group (1). Phytoplasmas were detected in 9 of 10 midvein extracts from symptomatic grapevines (three of cv. Plovdina, two of cv. Smederevka, and four of cv. Gamé). Also, 6 of 10 bark preparations representing stem collections from the same plants were positive (two samples of cv. Plovdina, both samples of cv. Smederevka, and two samples of cv. Gamé). Both collections of midveins and bark tissues from asymptomatic plants were negative. Fragments amplified with universal P1/P7 primers (16S-23S rDNA) were analyzed by restriction fragment length polymorphism with TruI and TaqI restriction enzymes. The phytoplasmas produced identical restriction profiles to those of 16SrV Elm Yellows group and 16SrV-C Flavescence doreé subgroup (2). To our knowledge, this is the first report of phytoplasma infecting grapevines in Serbia, and the first survey in progress to verify the presence of Scaphoideus titanus to determine if this grapevine yellows could be defined as Flavescence dorée. References: (1) E. Angelini et al. Vitis 40:79, 2001. (2) M. Martini et al. Mol. Cell. Probes 16:197, 2002.
First Report of a Field Outbreak of a Bacterial Leaf Spot of Cantaloupe and Squash Caused by Pseudomonas syringae pv. syringae in Georgia
Authors: Langston D. B. , Sanders F. H. , Brock J. H. , Gitaitis R. D. , Flanders J. T. , Beard G. H. 
Published: May 2007

In March 2000, a leaf spot was reported affecting yellow summer squash (Cucurbita pepo) and cantaloupe (Cucumis melo) in commercial fields in Colquitt, Echols, and Grady counties in Georgia. All of the crops affected were reported within a 10-day period, and average temperatures during that time were 8 to 22.5°C, which is very close to the 50-year normal temperatures for these areas located in southwest Georgia. Incidence in affected fields was 100%. Lesions on squash leaves appeared irregularly shaped, dark, water soaked, somewhat vein restricted, and were 5 to 10 mm in diameter. Lesions on cantaloupe were angular, light tan, and necrotic with a lesion diameter of 2 to 5 mm. A general chlorosis was observed around lesions of both crops. Leaf distortion was observed on squash. Four isolates collected were used in biochemical, pathogenicity, and physiological tests. Gram-negative, rod-shaped bacteria were isolated from diseased tissue from squash and cantaloupes. Bacteria were aerobic, catalase-positive, fluorescent on King's medium B (1), oxidase-negative, nonpectolytic on potato, arginine dihydrolase-negative, utilized sucrose as a carbon source, produced levan, and gave a hypersensitivity response on tobacco (HR). Analysis of fatty acid methyl ester (FAME) profiles using the Microbial identification system (Sherlock version 3.1, Microbial identification system, Newark, DE) characterized representative strains as Pseudomonas syringae (similarity indices 0.65 to 0.80). Upon further characterization, the strains were negative for l (+)-tartarate utilization but utilized l-lactate and betaine and also exhibited ice nucleation activity. These characteristics are consistent with those of Pseudomonas syringae pv. syringae. Squash and cantaloupes were grown in a greenhouse for 4 weeks. Bacteria were grown in nutrient broth, resuspended in sterile tap water, and standardized using a spectrophotometer. Plants were inoculated by infiltrating leaves with 1 ml of bacterial suspensions (1 × 107 CFU/ml) using sterile syringes. Sterile water was used as a negative control, and 1 ml was infiltrated into leaves of squash and cantaloupes. Water-soaked lesions developed in 4 to 6 days on squash and cantaloupes inoculated with bacterial suspensions, and Pseudomonas syringae pv. syringae was isolated from diseased tissue. No symptoms developed on squash and cantaloupes used as negative controls. This outbreak of Pseudomonas syringae pv. syringae did not cause significant economic damage to either crop as symptoms subsided once daily high temperatures reached 28 to 32°C. This disease has been isolated from several cucurbit transplants reared in greenhouses, but to our knowledge, this is the first report of this disease occurring in the field. Reference: (1) E. O. King et al. J. Lab. Clin. Med. 44:301, 1954.
Outbreaks of Alternaria Brown Spot of Citrus in Brazil and Argentina
Authors: Peres N. A. R. , Agostini J. P. , Timmer L. W. 
Published: May 2007

Alternaria alternata (Fr.) Keissler causes lesions on leaves, twigs, and fruit and reduces yield and fruit quality of many tangerines (Citrus reticulata) and their hybrids (2). Severe outbreaks of Alternaria brown spot were observed on ‘Murcott’ tangor (Citrus reticulata × Citrus sinensis) trees in southern São Paulo, southern Minas Gerais states in Brazil, and in Misiones and Corrientes provinces in Argentina. A single diseased ‘Fortune’ tangerine tree was observed in a grove in Misiones. On young leaves, brown-to-black lesions often expanded to cover large parts of the leaf, causing abscission of young shoots and dieback of twigs. Lesions were often surrounded by yellow halos. On fruit, dark specks from 0.2 to 0.5 cm were observed, and severe infection caused premature fruit abscission. Isolations were made on potato dextrose agar (PDA) after surface sterilization of leaf and fruit tissues in 1.5% sodium hypochlorite for 1 min. Plates were incubated at 27°C in the dark for 1 week. Isolated colonies were olive brown to black, and the fungus was stimulated to form conidia by scraping the surface of the mycelium. The pathogen was a typical small-spored Alternaria species, and the morphological characteristics of the conidia and conidiophores fit the description of A. alternata. Inoculation of three detached young shoots of ‘Murcott’ with a conidial suspension (105 conidia per ml) confirmed pathogenicity of three isolates obtained from widely separated groves in southern and eastern São Paulo State in Brazil and one from Misiones Province in Argentina. A control treatment with an equal number of shoots was sprayed with distilled water only. After 48 h, all isolates caused dark lesions on the leaves, characteristic of the disease. Symptoms were observed on inoculated, but not on control shoots. Koch's postulates were satisfied by reisolation of the fungus from symptomatic tissue in all cases. Although Alternaria brown spot was reported previously in neighboring Rio de Janeiro, Brazil on ‘Dancy’ and ‘Ponkan’ tangerines (1), serious disease problems now occur on ‘Murcott’, an important commercial variety in the major production area in Brazil. To our knowledge, this is the first report of Alternaria brown spot in Argentina. References: (1) A. de Goes et al. Fitopatologia Brasileira 26(Suppl.):386, 2001. (2) L. W. Timmer et al. Pages 19–21 in: Compendium of Citrus Diseases. 2nd ed. L. W. Timmer, S. M. Garnsey, and J. H. Graham, eds. The American Phytopathological Society, St. Paul, MN, 2000.
Occurrence of Nigrospora Lint Rot Caused by Nigrospora oryzae on Cotton in Alabama
Authors: Palmateer A. J. , McLean K. S. , van Santen E. , Morgan-Jones G. 
Published: May 2007

During 2000 and 2001, a lint rot of cotton bolls (Gossypium hirsutum L.) was reported in the coastal region of Alabama when precipitation was 55% lower than the 5-year average. Bolls at an early stage of opening contained gray mycelium within the locules. At maturity, the lint within the infected locules was discolored, and the fibers were compact resulting in the characteristic “gray lock” sign and symptom attributed to Nigrospora oryzae (Berk. & Broome) Petch. Roots, petioles, leaves, and bolls when present were sampled at the seedling, first bloom, full bloom, and maturity stages of cotton development. A total of 640 sections of tissue (approximately 5 mm2) were surface sterilized for 20 s in 95% ethanol followed by 60 s in 0.525% NaOCl and aseptically plated on potato dextrose agar. Plates were incubated in the dark at 25°C for 3 to 10 days. N. oryzae was isolated at low frequencies from all plant tissues beginning at first bloom. Developing bolls at full bloom were colonized at a frequency of 48%. N. oryzae conidiophores were branched, flexuous, and pallid to brown with smooth walls 4 to 7 (5) μm thick. Conidiogenous cells were monoblastic, single, and 6 to 9 (7.5) μm in diameter. Conidia were single, smooth, broadly ellipsoidal, dark brown to black, single-celled, and 11 to 16 (14) μm in diameter (2). Principal component analysis was used to examine the relationship between disease incidence and weather parameters. Weather data was obtained from Auburn University Mesonet located in fields where the samples were collected. Principal components from weather data were ambient and soil maximum, minimum, and average temperature, maximum, minimum, and average relative humidity and precipitation. The first principal component, which is temperature, accounted for 61% of total joint variation among original observations. The second principal component, which was related to the moisture variables, accounted for 19% of the variation. The abundance of N. oryzae was correlated with the principal component factor moisture (r = -0.78**). The dry conditions experienced in this region were conducive to N. oryzae lint rot of cotton. This disease has been reported on cotton primarily in arid climates typical of the southwestern United States (1). To our knowledge, this is the first report of N. oryzae lint rot in the southeastern United States. References: (1) W. E. Batson. Boll rots. Pages 36–38 in: Compendium of Cotton Diseases. T. L. Kirkpatrick and C. S. Rothrock, eds. The American Phytopathological Society, St. Paul, MN. 2001. (2) M. B. Ellis. Dematiaceous Hyphomycetes, CAB, Kew, Surrey, England, 1971.
First Report of Web Blight on Yellow-Sage (Lantana camara) Caused by Rhizoctonia solani in Europe
Authors: Garibaldi A. , Minuto A. , Bertetti D. , Nicoletti R. , Gullino M. L. 
Published: May 2007

Lantana camara is increasingly grown in northern Italy as a potted plant and contributes to the diversification of offerings in the ornamental market. During the spring of 2001, selections of L. camara cuttings growing at a commercial farm located at Albenga (Riviera coast) exhibited tan leaf spots of irregular size and shape. Spots were at first isolated, 4 to 8 mm in diameter, and later coalesced and affected the entire plant. Heavily infected leaves, stems, and branches became blighted and were killed. Infected rooted cuttings also eventually died. Diseased cuttings showed a progressive reduction (to less than 20%) in rooting ability. Isolations from infected leaves and stems on potato dextrose agar (PDA), supplemented with 100 mg/liter of streptomycin sulphate, consistently yielded a fungus with mycelial and cultural characteristics resembling Rhizoctonia solani. The fungal isolates were further characterized as R. solani Kühn AG-4 based on hyphal anastomoses with several AG-4 tester isolates. Pathogenicity tests were performed by placing 5-day-old-fungal mycelial plugs, grown on PDA, at the base of five healthy yellow-sage stems and holding plants in a dew chamber at 18 to 22°C. After 2 days, foliage blight appeared on leaves of inoculated plants, and after 3 days, stems also became infected and entire plants wilted. Five noninoculated plants remained healthy. The fungal pathogen was reisolated from all inoculated plants. R. solani has been observed on L. camara in the United States (1) and the Philippines (2). To our knowledge, this is the first report of R. solani on L. camara in Europe. 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) F. T. Orillo and R. B. Valdez. Philipp. Agric. A. 42:292, 1958.
First Report of Sirococcus conigenus on Deodar Cedar in Oregon
Authors: Bronson J. J. , Stanosz G. R. , Putnam M. L. 
Published: May 2007

Cedrus deodara is a highly valued conifer widely grown as an ornamental in the Pacific Northwest and southern United States. C. deodara in the Pacific Northwest is normally problem free but occasionally is damaged by dieback of shoot tips, which has been associated with a fungus resembling Sirococcus conigenus. In February 2002, bleeding cankers were observed on 2- to 4-year-old stems of potted nursery stock of C. deodara cv. Karl Fuchs from Clackamas County, OR. Cankers were dark with indistinct margins, shallow, and up to 30 cm long. Infection appeared to have originated with small twigs that had died. Cultures isolated from discolored bark on streptomycin-amended potato dextrose agar (PDA) produced conidiomata with hyaline, fusiform, two-celled conidia typical of S. conigenus (1,3). Inter-simple sequence repeat-polymerase chain reaction fingerprints of an isolate from one of these trees were consistent with the P group of S. conigenus (mostly from hosts in Picea and Pinus spp.) (2). This isolate (02–04, ATCC MYA-2969) was used to inoculate two shoots on each of 12 3-year-old potted deodar cedars in each of two trials. Removing a needle wounded each shoot, and an agar plug colonized with mycelium was placed over the wound and held in place for 2 weeks with Parafilm. Sterile agar plugs were applied to two wounded control shoots on each tree in each trial. After 10 weeks, 25 of 48 inoculated shoots were blighted and drooped with yellow to brown needles that eventually dropped. The pathogen was reisolated from 24 of 25 symptomatic shoots but not from asymptomatic or control shoots. To our knowledge, this is the first confirmed report of S. conigenus as a pathogen of C. deodara. References: (1) P. F. Cannon and D. W. Minter. Taxon 32:572, 1983. (2) D. R. Smith et al. For. Pathol. 33:141, 2003. (3) B. Sutton. The Coelomycetes. Commonw. Mycol. Inst., Kew, Surrey, England, 1980.
First Report of Heterobasidion parviporum (S Group of H. annosum sensu lato) on Tsuga spp. in Asia
Authors: Dai Y. C. , Korhonen K. 
Published: May 2007

Members of the Heterobasidion annosum (Fr.) Bref. complex are among the most important pathogens in coniferous forests of Europe and North America. Three intersterile groups (P, S, and F) have been found in this complex from Europe (1) and were recently segregated into three species based on intersterility, host preferences, and morphology (4). In a survey of wood-rotting fungi in China in 2002, Heterobasidion spp. were found on Tsuga chinensis (Franch.) Pritz and T. dumosa (D. Don) Eichl. in natural forests from the northern Sichuan Province of southwestern China (32°43′ to 33°11′ N, 103°50′ to 103°53′ E.). Basidiocarps of the fungus were relatively common on decayed wood in roots of dead trees, stumps, and fallen trunks. We collected four basidiocarps (Dai 4045, 4051, 4214, and 4224 in the Institute of Applied Ecology, Chinese Academy of Sciences, IFP) from three stands of mixed coniferous forests and made 40 homokaryotic, single-basidiospore cultures (02046, 02047, 02050, and 02051 in the Finnish Forest Research Institute). Two homokaryons from each basidiocarp were paired with homokaryotic tester strains of European H. annosum (P group), H. parviporum Niemelä & Korhonen (S group), and H. abietinum Niemelä & Korhonen (F group). The pairings showed that the progeny from the four basidiocarps are H. parviporum. The Chinese isolates did not form clamp connections with H. annosum sensu stricto, and a strong demarcation line developed in all these pairings. In contrast, the Chinese isolates formed clamp connections in almost every pairing with European H. parviporum, the clamp connections developed in both sides of the pairings, and no distinct demarcation line was present in most of these pairings. The Chinese homokaryons were also compatible with European H. abietinum, but in most of these pairings, clamp connections were found in the isolate from China but not in the European tester, and a demarcation line was present in most of the pairings. In contrast to H. annosum sensu stricto, the Chinese basidiocarps had smaller pores (4.5 to 6 per mm versus 3 to 4.5 per mm), and a thin tomentum on the pileal surface in contrast to the basidiocarps of H. abietinum. Previously, H. parviporum was found in Asia on coniferous hosts such as Abies, Larix, Picea and Pinus spp. (2). The North American S group of H. annosum sensu lato attacks species of Tsuga spp. in western North America (3), but to our knowledge, this is the first report of H. parviporum on native species of Tsuga spp. outside North America. References: (1) P. Capretti et al. Eur. J. For. Pathol. 20:231, 1990. (2) Y. C. Dai and K. Korhonen. Eur. J. For. Pathol. 29:273, 1999. (3) G. M. Filip and D. J. Morrison. North America. Pages 405–427 in: Heterobasidion annosum. Biology, Ecology, Impact and Control. CAB International, Wallingford, UK, 1998. (4) T. Niemelä and K. Korhonen. Taxonomy of the genus Heterobasidion. Pages 27–33 in: Heterobasidion annosum. Biology, Ecology, Impact and Control. CAB International, Wallingford, UK, 1998.
First Report of Papaya ringspot virus on Papaya in Iran
Authors: Pourrahim R. , Farzadfar Sh. , Golnaraghi A. R. , Shahraeen N. 
Published: May 2007

Papaya, a popular fruit crop native to the American tropics, was introduced to the southern tropical provinces of Iran in the 1990s and its cultivation is widely increasing in these areas. During April 2000, severe leaf distortion and mottling were observed on papaya trees (Carica papaya) in Hormozgan Province in southern Iran. Affected trees were stunted and yielded less fruit. Samples of papaya leaf extracts (1:10 wt/vol) in 0.01 M potassium phosphate buffer (pH 7.0) were mechanically inoculated on indicator host plants, causing local lesions on Chenopodium amaranticolor and C. quinoa and chlorotic spots followed by systemic mosaic symptoms on Cucurbita pepo. Papaya ringspot virus (PRSV) was detected in the leaf samples of papaya plants and the inoculated Cucurbita pepo plants using double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) with PRSV-specific antisera (polyclonal antibody AS-0086 and PV-0244, DSMZ, Braunschweig, Germany). PRSV causes one of the most destructive diseases of papaya worldwide (1). PRSV has been previously reported from Citrullus vulgaris and Cucumis melo from Iran as Watermelon mosaic virus 1 (2), but to our knowledge, this is the first report of occurrence of PRSV on papaya in Iran. References: (1) D. E. Purcifull et al. Papaya ringspot virus. No. 292. CMI/AAB, Surrey, England, 1984. (2) F. Ebrahim-Nesbat. Phytopathol. Z. 79:352, 1974.
First Report of Raspberry bushy dwarf virus on Red Raspberry and Grapevine in Slovenia
Authors: Mavrič I. , Marn M. Viršček , Koron D. , Žežlina I. 
Published: May 2007

In 2002, severe vein yellowing and partial or complete yellowing of leaves was observed on some shoots of red raspberry (Rubus idaeus) cvs. Golden Bliss and Autumn Bliss. Sap of infected plants of cv. Golden Bliss was inoculated onto Chenopodium quinoa and Nicotiana benthamiana. Faint chlorotic spots were observed on inoculated leaves of C. quinoa approximately 14 days after inoculation but no systemic symptoms appeared. No symptoms were observed on N. benthamiana. Raspberry bushy dwarf virus (RBDV) was detected in the original raspberry plant using double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) with polyclonal antiserum (Loewe Biochemica, Sauerlach, Germany). Systemic infections of inoculated C. quinoa and N. benthaminana were confirmed using DAS-ELISA. In 2001 and 2002, unusual virus symptoms were observed on grapevine grafts (Vitis vinifera) of cv. Laški Rizling. Symptoms appeared as curved line patterns and yellowing of the leaves. No nepoviruses were found in symptomatic plants, but RBDV was confirmed using DAS-ELISA. RBDV infection was later confirmed in grapevine cv. Štajerska Belina with similar symptoms. RBDV was transmitted mechanically from grapevine to C. quinoa where it was detected by immunocapture-reverse transcription-polymerase chain reaction (IC-RT-PCR). IC-RT-PCR was used to amplify a part of the coat protein gene of the virus from raspberry and grapevine, and the amplification products were sequenced (1). The obtained sequence shared at least 93% nucleotide sequence identity with other known RBDV sequences, which confirmed the serological results. To our knowledge, this is the first report of the natural occurrence of RBDV in grapevine and also of RBDV infection of red raspberry in Slovenia. Reference: (1) H. I. Kokko et al. Biotechniques 20:842, 1996.