bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rose Dieback Caused by Trichothecium roseum in Argentina
Authors: Wright E. R. , Pizzingrilli P. , Caligaris M. V. , Cabral D. 
Published: May 2007

Rose (Rosa sp.) is one of the most important ornamentals in Argentina. Since 2002, a severe disease has been observed on crops cultivated for cut flowers and garden plants in Escobar, San Pedro, Río Negro, and the surrounding area of Buenos Aires and La Plata. Symptoms consisted of a stem dieback progressing to plant death. In some cases, stem cankers were observed on the dieback limits. Mean incidence of stem dieback was 8% regardless of location. The disease was associated with pruning or harvest wounds. The objective of this study was to identify the causal agent of the described symptoms. Small pieces of diseased tissues from cvs. Rafaela, Merlise, Confeti, Mini rosal, Exótica, Macarena, and Peckowo were surfaced sterilized with a 2-min immersion in 0.2% NaOCl, washed with sterile distilled water, the tissue blotted dry, placed on 2% potato dextrose agar (PDA), and incubated at 22°C. Pure salmon-colored fungal colonies developed within 72 h. Hyaline, two-celled (the upper cell slightly larger), ovoid to ellipsoid conidia formed in chains at the apex of simple, long, slender, septate conidiophores. These characteristics are consistent with the description of Trichothecium roseum (Pers.) Link ex Gray (1) The pathogenicity tests were carried out on 10 plants of cv. Rafaela and 10 plants of cv. Mini Rosal using a conidial suspension (2.4 × 105 spores/ml). All plants were pruned just before inoculation. Another 10 pruned plants (five from each cultivar) were sprayed with sterile water and served as controls. Inoculated and noninoculated plants were placed in a climatic chamber at 20°C and covered with polyethylene bags for 3 days to achieve a humid environment. Stem dieback was evident 7 days after inoculation on both cultivars and cankers appeared in 14 days. A dense, white mold that turned salmon-pink covered all the stems within 25 days. Inoculated plants died after 40 days. Symptoms did not develop on the control plants. The pathogen was recovered from inoculated stems, thus fulfilling Koch's postulates. To our knowledge, this is the first report of T. roseum causing a disease on rose in Argentina. Reference: (1) K. H. Domsch et al. Compendium of Soil Fungi. Academic Press. London, 1980.
First Report of Powdery Mildew Caused by Golovinomyces orontii (Erysiphe orontii) on Petunia × hybrida in Italy
Authors: Garibaldi A. , Bertetti D. , Gullino M. L. 
Published: May 2007

Petunia × hybrida (Solanaceae) includes several hybrids that are grown as ornamental plants and are very much appreciated for their long-lasting flowering period. Among those, the variety pendula is often selected because of its hanging growth habit that is favorable for balcony decoration. During the summer of 2005, severe outbreaks of a previously unknown powdery mildew were observed on all petunia plants in several gardens near Biella and Torino (northern Italy). Both surfaces of the leaves of affected plants were covered with white, dense mycelia and conidia. As the disease progressed, infected leaves turned yellow and died. Mycelia also were observed on stems and flowers. Conidia were hyaline, ellipsoid, borne in short chains (with a maximum of four conidia per chain), and measured 27 to 36 × 17 to 21 μm (average 31 × 19 μm). Conidiophores, 130 to 154 μm (average 140 μm) long, showed the foot cell (measuring 42 to 65 × 10 to 12 μm, average 52 × 11 μm) followed by three shorter cells measuring 27 to 30 × 13 to 17 μm (average 29 to 14 μm). Fibrosin bodies were absent. Chasmothecia were not observed in the collected samples. The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 (3) and sequenced. BLASTn analysis (1) of the 588 bp obtained showed an E-value of 0.0 with Golovinomyces orontii (Erysiphe orontii) (2). The nucleotide sequence has been assigned GenBank Accession No. DQ 987491. Inoculations were made by gently pressing diseased leaves onto leaves of five healthy Petunia × hybrida var. pendula plants, belonging to cv. Surfinia. Five noninoculated plants served as controls. Inoculated and noninoculated plants were maintained in a greenhouse at temperatures between 14 and 30°C. After 10 days, typical powdery mildew symptoms developed on inoculated plants. Noninoculated plants did not show symptoms. The pathogenicity test was carried out twice. To our knowledge, this is the first report of the presence of powdery mildew on P. × hybrida caused by G. orontii in Italy. A powdery mildew of P. × hybrida reported in 1966 in Romania has been attributed to E. cichoracearum (4), while Braun (2) reported P. × hybrida as a possible host of E. orontii. Specimens of this disease are available at AGROINNOVA Collection, University of Torino, Italy. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) U. Braun. A Monograph of the Erysiphaceae (Powdery Mildews). Cramer, Berlin, GDR, 1987. (3) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (4) E. Eliade. Reprium nov. Spec. Regni veg.73:43, 1966.
First Report of Pelargonium zonate spot virus from Tomato in the United States
Authors: Liu H.-Y. , Sears J. L. 
Published: May 2007

Pelargonium zonate spot virus (PZSV) was first isolated from tomato in southern Italy in 1982 (1) and later was also reported from Spain (3) and France (2). Infected tomato plants showed stunting, malformation, yellow rings and line patterns on the leaves, and concentric chlorotic ringspots on the stems. In June of 2006, more than 100 tomato (Lycopersicon esculentum Mill.) plants exhibiting symptoms similar to PZSV were observed in seven acres of tomato fields in Yolo County, California. The causal agent was mechanically transmitted to several indicator species. Symptoms on infected plants included local lesions on Beta macrocarpa, Chenopodium amaranticolor, C. capitatum, C. quinoa, Cucumis melo, Cucurbita pepo, and Tetragonia expansa, and systemic infection on Capsicum annuum, Chenopodium murale, L. esculentum, Nicotiana benthamiana, N. clevelandii, N. glutinosa, N. tabacum, Physalis floridana, and P. wrightii. Two field-infected tomato plants and one each of the mechanically inoculated host plant were positive with double-antibody sandwich (DAS)-ELISA using a commercial PZSV IdentiKit (Neogen Europe Ltd., Ayr, Scotland, UK). Partially purified virions stained with 2% uranyl acetate contained spherical to ovate particles. The particle diameters ranged between 25 and 35 nm. Published sequences of PZSV (GenBank Accession Nos. NC_003649 for RNA1, NC_003650 for RNA2, and NC_003651 for RNA3) were used to design three sets of primer pairs specific for PZSV RNA1 (R1-F: 5′ TGGCTGGCTTTTTCCGAACG 3′ and R1-R: 5′ CCTAATCTGTTGGTCCGAACTGTC 3′), RNA2 (R2-F: 5′ GCGTGCGTATCATCAGAAATGG 3′ and R2-R: 5′ ATCGGGAGCAG AGAAACACCTTCC 3′), and RNA3 (R3-F: 5′ CTCACCAACTGAAT GCTCTGGAC 3′ and R3-R: 5′ TGGATGCGTCTTTCCGAACC 3′) for reverse transcription (RT)-PCR tests. Total nucleic acids were extracted from field-infected tomato plants and partially purified virions for RT-PCR. RT-PCR gave DNA amplicons of the expected sizes. The DNA amplicons were gel purified and sequenced. The sequenced amplicons had 92, 94, and 96% nt sequence identity to PZSV RNA1, RNA2, and RNA3, respectively. The symptomatology, serology, particle morphology, and nucleotide sequences confirm the presence of PZSV in a tomato field in California. To our knowledge, this is the first report of the occurrence of PZSV in the United States. References: (1) D. Gallitelli. Ann. Appl. Biol. 100:457, 1982. (2) K. Gebre-Selassie et al. Plant Dis. 86:1052, 2002. (3) M. Luis-Arteaga et al. Plant Dis. 84:807, 2000.
A Polish Isolate of Zucchini yellow mosaic virus from Zucchini is Distinct from Other European Isolates
Authors: Pospieszny H. , Hasiów B. , Borodynko N. 
Published: May 2007

Zucchini yellow mosaic virus (ZYMV) is a member of the Potyvirus genus in the Potyviridae family, the largest group of plant viruses. Different isolates of this virus have been found in infected cucurbits throughout the world, including localities in Europe, America, Australia, and Asia. In August 2005, mosaic and yellowing of leaves, as well as yellow spots on green fruits, were observed on zucchini (Cucurbita pepo cv. giromontiina) growing in commercial fields in the Kujawsko-Pomorskie Region of Poland. Flexuous virus particles (~750 nm long), typical of potyviruses, were observed in leaf-dip preparations from symptomatic zucchini plants. The virus in the sap from symptomatic plants was mechanically transmitted and systemic infections were produced on Citrullus lanatus, Cucumis melo, Cucumis sativus, C. pepo cvs. giromontiina and patissoniana, C. maxima, and Nicotiana benthamiana. Severe symptoms such as severe malformation of leaves and stunting of plants were observed on zucchini plants (cv. giromontiina) infected mechanically with the virus and grown in the greenhouse. Double-antibody sandwich (DAS)-ELISA using an anti-ZYMV polyclonal antiserum (AS-0234; DSMZ, Braunschweig, Germany) identified the presence of ZYMV in mechanically infected C. pepo cv. giromontiina and N. benthamiana plants. Subsequently, a reverse transcription (RT)-PCR using a universal primer, Sprimer, designed from the consensus sequences that code for the conserved sequence GNNSGQP in the NIb region of Potyviridae family members and the M4 primer was performed (1). The 1740-bp PCR fragments were cloned into the pGEM-T vector (Promega, Madison, WI) and three randomly selected clones were sequenced on an ABI automatic sequencer. An 837-bp sequence representing the full length coat protein gene (GenBank Accession No. EF178505) was compared with homologous sequences from other ZYMV isolates using BioEdit and Mega 3.1 softwares. Genetic distances were calculated by Kimura's two-parameter method (2). Surprisingly, the Polish ZYMV isolate (ZYMV-Zug) was more closely related to ZYMV isolates from Asia than those from Europe. Pairwise comparisons of ZYMV-Zug with several other European ZYMV isolates (GenBank Accession Nos. DQ645729, AJ420020, AJ459956, AJ420014, AJ420019, DQ124239, and AJ420018) indicated an 81 to 82% nucleotide and 91 to 92% amino acid identity, while there was a 94% nucleotide and 99% amino acid identity with the Shanxi (GenBank Accession No. AY074808) and Shandong isolates (GenBank Accession No. AF513552) from China. References: (1) J. Chen et al. Arch. Virol. 146:757, 2001. (2) S. Kumar et al. Brie. Bioinform. 5:150, 2004.
A New Geminivirus Associated with a Leaf Curl Disease of Tomato in Tanzania
Authors: Chiang B.-T. , Nakhla M. K. , Maxwell D. P. , Schoenfelder M. , Green S. K. 
Published: May 2007

Leaf samples of tomato exhibiting yellow mottle, severe leaf curl, stunting, and upright stems were collected from Makutupora, Tanzania, in October 1994 by L. L. Black (AVRDC). Leaf tissue squashes on nylon membranes did not hybridize with DNA-A probes from tomato yellow leaf curl geminiviruses (TYLCVs) from Thailand (Thai) or Egypt (EG), an isolate of TYLCV-Isr (Israel). Polymerase chain reaction (PCR) with primer pair PAC1v1978/PAV1c715 (2), which specifically amplifies part of the rep (AC1) open reading frame (ORF), the intergenic region, and the cp (AV1) ORF of whitefly-transmitted geminiviruses, yielded a 1.5-kb fragment from a DNA extract of symptomatic tomato leaves. No virus-specific fragments were amplified from symptomless tomato leaves. The nucleotide sequence (GenBank accession no. U73478) of the PCR fragment (recombinant plasmid pAF1) was compared with the sequences of seven distinct subgroup III geminiviruses that infect tomato (1)—TYLCV-Isr, TYLCV-Sar (Sardinia), TYLCV-Thai, tomato leaf curl virus (TLCV)-;Aus (Australia), IndTLCV (India), TLCV-Ind (Bangalore I), and TLCV-Tai (Taiwan)—as well as three other subgroup III geminiviruses from the Old World: Indian cassava mosaic virus, African cassava mosaic virus, and mung bean yellow mosaic virus. Nucleotide sequence identities for the pairwise comparisons of the rep ORF (692 nucleotides) and the intergenic region (169 nucleotides) of this Tanzanian geminivirus with those of the 10 Old World geminiviruses showed low nucleotide identities, which were <79% for the rep ORF and <67% for the intergenic region. Since isolates of the same geminivirus usually have nucleotide sequence identities >90% (1), this Tanzanian geminivirus is considered to be different from all previously characterized Old World geminiviruses and is given the name TLCV-Tan. Further, tissue squash blots of samples previously collected from other areas in Tanzania gave strong positive reactions with the TYLCV-EG probe, so yet another geminivirus closely related to TYLCV-Isr may be present. References: (1) M. Padidam et al. J. Gen. Virol. 76:249, 1995. (2) M. R. Rojas et al. Plant Dis. 77:340, 1993.
First Report of Alternaria Brown Spot of Minneola Tangelo in Turkey
Authors: Canihos Y. , Erkilic A. , Timmer L. W. 
Published: May 2007

Minneola tangelo, a hybrid of Dancy tangerine and Duncan grapefruit, is widely grown in Turkey for export to Europe. In 1995, 2,000 ha of diseased Minneola tangelo trees were observed in the Cukurova region. Ninety percent of orchards in this region were diseased but disease severity depended upon the location and the disease control strategies employed in each orchard. Symptoms were typical of Alternaria brown spot (1). Fruit symptoms included light brown, slightly depressed spots to circular and dark brown areas on the external surface. On leaves, symptoms ranged from small brown circular spots to irregular blighted areas with characteristic yellow halos. The apices of some young shoots were defoliated. Infected young fruit and leaves often dropped from the tree and the mature fruit were unmarketable due to lesions on the fruit. Alternaria was consistently isolated from diseased leaves and fruit on potato dextrose agar and produced dark brown mycelia and pigmented septate conidia similar to those described previously (1). Detached immature Minneola leaves were inoculated with aqueous conidial suspensions of 15 isolates and maintained in a chamber at near 100% relative humidity for 3 days at 26°C. Thirteen of these isolates caused necrotic lesions on the leaves similar to those observed in the field, i.e., dark, necrotic spots with necrosis extending outward on some veins. Alternaria was reisolated from all infected leaves. This is the first report of Alternaria brown spot of Minneola tangelo in Turkey. Reference: (1) Z. Solel. Plant Pathol. 40:145, 1991.
First Report of Monosporascus cannonballus on Melons in Saudi Arabia
Authors: Karlatti R. S. , Abdeen F. M. , Al-Fehaid M. S. 
Published: May 2007

In the late summer of 1996, a root rot and vine decline was noticed on greenhouse grown melons (Cucumis melo L.) at the National Agriculture and Water Research Center, Riyadh, Saudi Arabia. Melons were grown on sandy clay soil and peat moss was spot applied as organic manure. The pH of the soil was 7.8. Disease symptoms first appeared at early stage of fruit maturity of the crop. Diseased vines exhibited stunting, yellowing, and, at a late stage, complete collapse of the leaf canopy. The roots showed discoloration, discrete lesions on all root systems, and loss of secondary and tertiary feeder roots. Numerous perithecia were observed on the secondary and tertiary roots only. Each ascus contained one large spherical ascospore. The fungus was isolated on potato dextrose agar and identified as a Monosporascus sp. (2). A pure culture was confirmed as Monosporascus cannonballus Pollack & Uecker. IMI (373485(01)) by IMI, Surrey, U.K. Pathogenicity was confirmed in a temperature-controlled growth chamber on the melon cv. Red Queen(F1). A medium that consisted of 3 liters of sand, 275 g of dried ground oat hulls, and 450 ml of distilled sterile water (1) was inoculated and incubated for 40 days. The colonized medium (100 ml) was mixed with a pasturized potting mix (sand/peat moss; 1:1) in 17-cm-diameter plastic pots. Five seeds were planted in each pot and, 15 days after germination, seedlings were thinned to one per pot. Noninfested pots were inoculated with sterile sand/oat hull medium. The pots were placed in chambers maintained at 30/20°C, day/night. At various intervals, the onset and severity of symptom expression were recorded. The isolate caused stunting and root necrosis. The fungus was reisolated from symptomatic plants. This report extends the known range of M. cannonballus to include Saudi Arabia. Other reports of this fungus are from India, Israel, Japan, Libya, Mexico, Spain, Taiwan, Tunisia, and the U.S. References: (1) J. C. Mertely et al. Plant Dis. 77:667, 1993. (2) F. G. Pollack and F. A. Uecker. Mycologia 66:346, 1974.
First Report of Cucurbit Aphid-borne Yellows Luteovirus in Lebanon
Authors: Abou-Jawdah Y. , Sobh H. , Fayyad A. 
Published: May 2007

Recently, Lecoq et al (1992) reported a new yellowing disease of cucurbits in France caused by cucurbit aphid-borne yellows luteovirus (CABYV) (1). Yellowing of older leaves of cucurbits has been observed in Lebanon for the past few years. Transmission tests showed that the disease incitant could be transmitted by Aphis gossypii in a persistent, circulative manner from muskmelon plants (Cucumis melo) to cucumber (C. sativus), muskmelon (C. melo), and squash (Cucurbita pepo) plants. Extracts from these plants reacted positively in enzyme-linked immunosorbent assays (ELISAs) with an antiserum prepared to a French isolate of CABYV. Surveys conducted in 1995 and 1996 showed that CABYV was widely distributed in the major cucurbit-growing areas along the Lebanese coast from north to south, and in the Beqaa plain. It was detected year round, alone or in mixed infections with mosaic-inducing viruses. The highest frequencies were recorded between May and October. CABYV and zucchini yellow mosaic potyvirus (ZYMV) were the most commonly detected viruses in outdoor cucurbits, including squash, cucumber, and melon. However, in protected cultivations (plastic tunnels), only a small proportion of cucumber plants showing similar yellowing symptoms reacted positively with CABYV antiserum in ELISAs, suggesting another cause to account for these symptoms. Reference: (1) H. Lecoq et al. Plant Pathol. 41:479, 1992.
A Vascular Wilt of Fragrant Sumac Caused by Fusarium oxysporum
Authors: O'Mara J. , Tisserat N. 
Published: May 2007

A branch from a wilting fragrant sumac tree (Rhus aromatica Aiton) in an established ornamental planting was submitted to the Plant Disease Diagnostic Laboratory in 1994. The branch exhibited dark brown streaks in the sapwood. Fusarium oxysporum Schlechtend.:Fr. was subsequently isolated from the discolored wood. To confirm pathogenicity, 2-year-old potted sumacs (0.5 to 1 m high)—fragrant, skunkbrush (R. trilobata Nutt. ex Torr. & A. Gray), smooth (R. glabra L.), and staghorn (R. typhina L.) species—were inoculated with the isolate by cutting into the bark to the xylem with a scalpel and applying approximately 0.1 ml of a 106 conidia/ml suspension into the wound. Inoculated trees were then placed on a greenhouse bench. Three trees of each species were inoculated and the experiment was repeated once. All inoculated skunkbrush and fragrant sumacs wilted and died within 3 months, whereas none of the smooth and staghorn sumacs were affected. F. oxysporum was consistently reisolated from wilted, but not healthy, trees. The host range of this isolate (FRC 0-1916) is different from that of F. oxysporum f. sp. rhois W. C. Synder, Toole, & Hepting, which was reported to be pathogenic to staghorn but not other sumac species (1). This is the first report of F. oxysporum causing wilt of fragrant and skunkbrush sumacs. Reference: (1) E. R. Toole. Phytopathology 39:754, 1949.
Expanded Range of Cylindrocladium colhounii in the United States
Authors: El-Gholl N. E. , Schubert T. S. , Walker S. E. , Stone J. K. 
Published: May 2007

Plant pathologists in Florida and Oregon have recently found Cylindrocladium colhounii for the first time on two new ornamental plant species. Brown, pinpoint leaf spots were observed on Callistemon rigidus (stiff bottlebrush) in a Florida nursery. C. colhounii was isolated consistently from these lesions. To confirm Koch's postulates, 25 ml of aconidial suspension at 96,000 conidia per ml was used to spray a 38.1-cm branch of C. rigidus. Plants were maintained in a moist chamber at room temperature (25 ± 2°C). Symptoms appeared within 3 days, and included brown, pinpoint spots (1 mm or less) occurring on both leaf surfaces, sunken blotches, and blight. The fungus was consistently reisolated from symptomatic tissue. In Oregon, the first detection of C. colhounii was from leaf spots on Gaultheria procumbens (wintergreen) in a nursery. No proof of pathogenicity was done in Oregon on G. procumbens. C. colhounii has now been reported on 14 host genera in 10 families from Australia, India, Mauritius, South Africa, and the U.S. (FL, HI, LA, NC, OR, SC) (1–4). References: (1) P. W. Crous and M. J. Wingfield. Mycopathologia 122:45, 1993. (2) A. Peerally. Mycotaxon 40:323, 1991. (3) A. Y. Rossman. Mycol. Pap. No. 150, Commonw. Mycol. Inst., Kew, Surrey, England, 1983. (4) J. Y. Uchida and M. Aragaki. Plant Dis. 81:298, 1997.
Detection of a Severe Isolate of Impatiens Necrotic Spot Virus Infecting Lisianthus in Florida
Authors: McGovern R. J. , Polston J. E. , Harbaugh B. K. 
Published: May 2007

In May 1997, inclusions typical of a tospovirus were visualized by light microscopy in leaf tissue of lisianthus (Eustoma grandiflorum) exhibiting stunting, necrotic ringspots, leaf distortion, and systemic necrosis. Wilting and plant death were the final symptoms observed. Affected plants occurred at low incidence (<0.1%) in greenhouse-grown lisianthus in Manatee County, FL. Symptomatic tissue tested positive for impatiens necrotic spot virus (INSV) and negative for tomato spotted wilt virus (TSWV) with enzyme-linked immunosorbent assay (ELISA; Agdia, Elkhart, IN). Mechanical transmission of the virus to lisianthus and tomato was attempted by triturating 1 g of symptomatic leaf tissue in 7 ml of a buffer consisting of 0.01 M Tris and 0.01 M sodium sulfite, pH 7.3. Six plants of lisianthus cv. Maurine Blue and three of tomato (Lycopersicon esculentum) cv. Lanai at the second true-leaf stage were inoculated following abrasion of leaves with Carborundum. An equal number of controls were inoculated with buffer alone. Plants were maintained in a controlled environment chamber with a 12-h photoperiod, day/night temperatures of 21/16°C, and light intensity of 120 μE · s-l · m-2. Transmission rates were 100 and 0% to lisianthus and tomato, respectively. Chlorotic local lesions followed by chlorotic ringspots were observed in inoculated lisianthus leaves 4 days after inoculation. Stunting, leaf distortion, and necrotic ringspots appeared in noninoculated leaves of lisianthus plants within 3 to 4 weeks after inoculation. Buffer-inoculated lisianthus and all tomato plants remained symptomless and tested negative for INSV by ELISA. All symptomatic lisianthus tested positive for INSV by ELISA. The symptoms we observed in lisianthus due to infection by INSV were more severe than those previously reported in this host (1,2). The occurrence of such strains of INSV at high incidences could pose a significant threat for commercial lisianthus production. References: (1) M. K. Hausbeck et al. Plant Dis. 76:795, 1992. (2) H. T. Hsu and R. H. Lawson. Plant Dis. 75:292,1991.