bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of Botryosphaeria dothidea on Sycamore, Red Oak, and English Oak in Northwestern Italy
Authors: Turco E. , Marianelli L. , Vizzuso C. , Ragazzi A. , Gini R. , Selleri B. , Tucci R. 
Published: May 2007

The Parco Nord Milano, Italy is a 600-ha green area (45°53′71″N, 9°20′97″E). Since the spring of 2002, extensive and unknown decline was observed on 20-year-old sycamore (Acer pseudoplatanus), red oak (Quercus rubra), and English oak (Q. robur) plantations. The trees showed branch and twig dieback associated with bark cankering along the whole stem and an irregular to wilted crown. A closer inspection of the inner part of the symptomatic trunk and roots revealed a dark bluish tissue discoloration. From the symptomatic trunk and root tissue, a dark gray abundant mycelium was consistently isolated on potato dextrose agar (PDA). The sequenced internal transcribed spacer (ITS) regions of rDNA (GenBank Accession Nos. DQ198265, DQ198266, and DQ198267) showed 99% identity to Botryosphaeria dothidea strain CBS110302 (GenBank Accession No. AY259092). A Fusicoccum sp. with black pycnidia was consistently collected from the cankers. The conidia were hyaline, aseptate, fusiform to narrowly ellipsoidal, with a truncate base (22 × 4.5 μm), referred to as Fusicoccum aesculi (CBS identification), the anamorph of B. dothidea (2). Pathogenicity tests were conducted for all three hosts by stem inoculation on 18-month-old seedlings growing in plastic pots containing a 2:1 turf/sand mixture. Two experiments were conducted using two inoculation techniques. In the first trial, 6-mm-diameter mycelial plugs of B. dothidea were applied to 6-mm-long bark wounds. The same inoculation method was used for application to bark without wounding. Control seedlings were inoculated with sterile agar plugs in a similar fashion as above. Inoculated and control seedlings were kept in a growth chamber and watered once per week. In the second trial, segments of branches 15-cm long were inoculated with 6-mm-diameter B. dothidea plugs (1), with and without any wounding. Control segments of branches were treated with sterile agar plugs in place of fungal mycelium. The branches were incubated at 23°C in moist chambers. For both experiments, the inoculated stem portions were wrapped with Parafilm to prevent desiccation. There were three replicate seedlings per inoculation technique, experiment, and plant species. After 2 months, all seedlings showed bark cankers and pycnidial formation, while the controls were symptomless. An inner dark bluish stem tissue discoloration was observed. The symptoms were more abundant on the segment of branches where the inoculum was applied to the wounded bark. B. dothidea was successfully reisolated, confirming Koch's postulates. To our knowledge, although it is accepted as synonymous of B. berengeriana (2), this is the first report of B. dothidea on sycamore, red oak, and English oak in Italy. The fungus was previously reported in Italy to cause canker on Platanus spp. References: (1) M. E. Sanchez et al. Plant Dis. 87:1515, 2003. (2) B. Slippers et al. Mycologia 96:83, 2004.
First Report of the Barley Root-Knot Nematode Meloidogyne naasi Infecting Annual Bluegrass on a Golf Course in Quebec, Canada
Authors: Bélair G. , Simard L. , Eisenback J. D. 
Published: May 2007

Annual bluegrass, Poa annua L., is an important component of the vegetation on golf course greens and fairways throughout Canada and is widely distributed across the world (2). The barley root-knot nematode, Meloidogyne naasi Franklin, infects and damages cereals such as barley (Hordeum vulgare), sorghum (Sorghum vulgare), and wheat (Triticum durum and T. vulgare), mainly in Europe. Of the root-knot species, M. naasi in particular, prefers grasses over other hosts, and infestations of this nematode can reduce the growth and vigor of turfgrasses (1). In July 2005, annual bluegrass at Beaconsfield Golf Club in Pointe Claire (45°26′N, 73°50′W), Quebec showed signs of an unidentified disease. Irregular yellowish/chlorotic patches were observed on the collar of one golf green. Lower turfgrass density in the turf areas with symptoms was noted. When roots were examined under a dissecting microscope, galling was observed. Upon dissection of washed galls, root-knot nematode egg masses and mature females inside the roots were observed. Nematode extractions of the soil from two samples of 50 g from the green and around the collar and perimeter were also done by the modified Baermann pan method. No juveniles were recovered from soil samples from the healthy area and an average of 400 and 1,500 juveniles/kg dry soil were counted in collar and perimeter samples of the patches. Morphological identification of mature females and juveniles were performed and confirmed to be M. naasi. Currently, there are no regulations to control the introduction of this nematode into Canada. To our knowledge, this is the first report of the occurrence of M. naasi in Canada where it is causing noticeable damage to turfgrass in Quebec. A soil survey is currently underway to examine the distribution of this nematode on golf course turfgrasses in Ontario and Quebec. References: (1) R. Cook and G. W. Yeates. Nematode pests of grassland and forage crops. Pages 305–350 in: Plant Parasitic Nematodes in Temperate Agriculture. K. Evans et al., eds. CAB International, Wallingford, UK, 1993. (2) S. I. Warwick. Can. J. Plant Sci. 59:1053, 1979.
First Report of Acidovorax avenae subsp. citrulli Infecting Edible Seed Watermelon (Citrullus lanatus var. lanatus) in China
Authors: Ren Y. Z. , Li H. , Li G. Y. , Wang Q. Y. , Li J. Q. 
Published: May 2007

Edible seed watermelon, Citrullus lanatus var. lanatus, is a type of watermelon from which only the seeds are consumed. Between 2003 and 2005, a bacterial disease was discovered on this type of watermelon in several regions of Xinjiang Province in western China, with a diseased area of 40,000 ha. The average disease incidence on fruit and seedlings was approximately 30 and 20%, respectively. Symptoms were most noticeable on fruit. Lesions on the fruit rind were first noticeable as small pinpoint water-soaked areas. As the lesions rapidly enlarged, black, starshaped cracks formed in the rind, and the rind along with the flesh around the spots hardened. If no secondary invaders or saprophytes entered through the cracks, the inside flesh often disintegrated into dry stiff cavities. The fruit with necrotic spots became markedly malformed. The pathogen also infected seedlings. First symptoms on the seedling appeared as dark, water-soaked lesions on the underside and edge of the cotyledons. As the cotyledon expanded, the lesions become necrotic and often extended along the length of the midrib and eventually merged into large, black, withered areas. To determine the causal agent of the disease, 54 bacterial strains were isolated from cotyledons, fruits, or seeds of edible seed watermelon. By spray inoculation, these strains were inoculated onto edible seed watermelon cv. Xinzigua1 at the two-true-leaf stage with bacterial concentrations at 107 CFU/ml. All strains were strongly virulent to cv. Xinzigua1, which is planted in large areas in Xinjiang, by forming many water-soaked spots on cotyledons and true leaves. There were no symptoms in the control that was sprayed with sterile deionized water. Through biological and biochemical characteristics, including Gram reaction and tests for catalase, oxidase, and oxygen requirement, all strains were identified as Acidovorax avenae subsp. citrulli. To verify pathogen identification, specific polymerase chain reaction was also carried out. One set of 16S primers, WFB1/WFB2 for A. avenae subsp. citrulli, was used (1). A single unique band of approximately 360 bp was amplified for all strains tested. To our knowledge, this is the first report of A. avenae subsp. citrulli infecting edible seed watermelon. Reference: (1) R. R. Walcott and R. D. Gitaitis. Plant Dis.84:470, 2000.
First Report of Crown Rot of Gazania rigens Caused by Sclerotinia sclerotiorum in Louisiana
Authors: Holcomb G. E. 
Published: May 2007

Gazania rigens (L.) (treasure flower, Asteraceae) is grown as a winter and summer annual bedding plant in Louisiana and the lower southern United States. In March 2006, cv. Kiss Mix was observed in a wholesale nursery with symptoms of leaf yellowing, wilt, crown rot, and death. White mycelia and black sclerotia were present on some infected and dead plants. The plants had been grown outdoors and approximately 2% of 1,120 plants had been lost. Petiole and crown tissue from infected plants were surface disinfected in 70% ethyl alcohol, and sections were placed on acidified potato dextrose agar (PDA). A fungus that produced white mycelia and black sclerotia consistently grew from tissue pieces. Other characteristics included production of numerous sclerotia (32 to 71 per dish from 10 dishes) that were oval to oblong and formed in a ring at the periphery of culture dishes. Sclerotia measured 3 to 7 mm long (mean = 4.4, standard error = 0.15, N = 50) × 2 to 4 mm wide (mean = 3.0, standard error = 0.06, N = 50). Cells of sclerotial rinds were globose and lacked erect tomentum hyphae (1). Growth rate of the fungus at 26°C on PDA ranged from 1.3 to 3.1 cm/day (mean = 2.2, standard error = 0.05, N = 45) and mycelia covered the dishes after 3 days (2). On the basis of these characteristics, the fungus was identified as Sclerotinia sclerotiorum (Lib.) de Bary. Fungal inoculum for pathogenicity tests was grown on twice-sterilized wheat grains and 1 g of 10-day-old inoculum, consisting of fungus mycelia and sclerotia, was placed at the base of six G. rigens cv. Daybreak Mix plants. Inoculated and noninoculated control plants were placed in a dew chamber held at 22°C for 48 h and then moved to a greenhouse where temperatures ranged from 20 to 25°C. Leaf yellowing, wilt, and crown rot developed after 3 to 4 days on all inoculated plants followed by death after 6 days. S. sclerotiorum was reisolated from all inoculated plants. Noninoculated plants remained healthy. Sclerotinia crown rot of G. rigens was first reported in the United States from California (3) and has also been reported from Italy and Argentina (4). To our knowledge, this is the first report of Sclerotinia crown rot on G. rigens in Louisiana. References: (1) L. M. Kohn. Phytopathology 69:881, 1979. (2) G. Li et al. Mycol. Res. 104:232, 2000. (3) V. M. Muir and A. H. McCain. Calif. Plant Pathol. 16:1, 1973. (4) S. M. Wolcan. J. Plant Path. 86:263, 2004.
First Report of Phytophthora citrophthora on Penstemon barbatus in Italy
Authors: Garibaldi A. , Bertetti D. , Minerdi D. , Gullino M. L. 
Published: May 2007

Penstemon barbatus (Cav.) Roth (synonym Chelone barbata), used in parks and gardens and sometimes grown in pots, is a plant belonging to the Scrophulariaceae family. During the summers of 2004 and 2005, symptoms of a root rot were observed in some private gardens located in Biella Province (northern Italy). The first symptoms resulted in stunting, leaf discoloration followed by wilt, root and crown rot, and eventually, plant death. The diseased tissue was disinfested for 1 min in 1% NaOCl and plated on a semiselective medium for Oomycetes (4). The microorganism consistently isolated from infected tissues, grown on V8 agar at 22°C, produced hyphae with a diameter ranging from 4.7 to 5.2 μm. Sporangia were papillate, hyaline, measuring 43.3 to 54.4 × 26.7 to 27.7 μm (average 47.8 × 27.4 μm). The papilla measured from 8.8 to 10.9 μm. These characteristics were indicative of a Phytophthora species. The ITS region (internal transcribed spacer) of rDNA was amplified using primers ITS4/ITS6 (3) and sequenced. BLASTn analysis (1) of the 800 bp obtained showed a 100% homology with Phytophthora citrophthora (R. & E. Sm.) Leonian. The nucleotide sequence has been assigned GenBank Accession No. DQ384611. For pathogenicity tests, the inoculum of P. citrophthora was prepared by growing the pathogen on autoclaved wheat and hemp kernels (2:1) at 25°C for 20 days. Healthy plants of P. barbatus cv. Nano Rondo, 6 months old, were grown in 3-liter pots (one plant per pot) using a steam disinfested substrate (peat/pomix/pine bark/clay 5:2:2:1) in which 200 g of kernels per liter of substrate were mixed. Noninoculated plants served as control treatments. Three replicates were used. Plants were maintained at 15 to 20°C in a glasshouse. The first symptoms, similar to those observed in the gardens, developed 21 days after inoculation, and P. citrophthora was consistently reisolated from infected plants. Noninoculated plants remained healthy. The pathogenicity test was carried out twice with similar results. A nonspecified root and crown rot of Penstemon spp. has been reported in the United States. (2). To our knowledge, this is the first report of P. citrophthora on P. barbatus in Italy as well as in Europe. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997 (2) F. E. Brooks and D. M. Ferrin. Plant Dis. 79:212, 1995. (3) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (4) H. Masago et al. Phytopathology 67:425, 1977.
First Report of Melon necrotic spot virus in Panama
Authors: Herrera J. A. , Cebrián M. C. , Jordá C. 
Published: May 2007

Melon (Cucumis melo L.) represents an important crop in Panama where 1,449 ha were cultivated in 2005 with 920.4 ha of this crop planted in Los Santos Province (southeast region of Panama). During April 2005 and January 2006, several melon plants in commercial fields in that area showed stem necrosis at the crown level, and less frequently, small necrotic spots on leaves. In some cases, wilting and plant death were observed. Symptoms were similar to those caused by the carmovirus Melon necrotic spot virus (MNSV). Cysts of Olpidium bornovanus also were observed in the roots of all affected melon plants. Roots from eight symptomatic plants collected in seven fields were positive using doubleantibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) with an antiserum specific for MNSV (BIO-RAD, Life Sciences, Barcelona, Spain). To confirm these results, total RNA was extracted from symptomatic plants and used in one-step reverse transcription-polymerase chain reaction (RT-PCR) with Platinum Taq (Invitrogen Life Technologies, Barcelona, Spain). MNSV specific primers designed to amplify a region of the coat protein gene were used in the assays. Amplicons of the expected size (651 bp) were generated from symptomatic plant tissue, but were not produced from healthy plants or the water used as negative controls. To establish the authenticity of this virus, RT-PCR products were purified with the High Pure PCR Product Purification Kit (Roche Diagnostics, Mannheim, Germany) and directly sequenced. Nucleotide sequences were analyzed by using the basic local alignment search tool (BLAST) (1). The primers produced two amplicons with different but similar sequences. One sequence (GenBank Accession No. DQ443546) showed 92% identity to the coat protein gene of the MNSV Spanish isolate (GenBank Accession No. AY330700) and the MNSV Dutch isolate (GenBank Accession No. M29671) and 88% identity to the Japanese isolate (GenBank Accession No. AB189944). The second sequence (GenBank Accession No. DQ443547) was 93% identical with the Spanish and Dutch MNSV isolates, 88% identical with the Japanese isolate, and 100% identical with sequences from commercial melon seed previously isolated in our laboratory (GenBank Accession No. DQ443545). Infected seed may be a concern with regard to long distance spread of the virus independent of the vector (3) and should be considered in disease management strategies. MNSV has been previously reported in Japan, the Netherlands, the United Kingdom, the United States (2), Guatemala (4), Mexico, Honduras, and Uruguay (C. Jordá, unpublished). To our knowledge, this is the first report of MNSV in Panama. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) A. A. Brunt et al. Plant Viruses Online: Descriptions and Lists from the VIDE Database. Online Publication, 1996. (3) R. N. Campbell et al. Phytopathology 86:1294, 1996. (4) C. Jordá et al. Plant Dis. 89:338, 2005.
Types A and B of Beet necrotic yellow vein virus Occur in Poland
Authors: Borodynko N. 
Published: May 2007

Beet necrotic yellow vein virus (BNYVV) is the type member of the genus Benyvirus and the causal agent of rhizomania disease of sugar beet. Since 1999, BNYVV is becoming one of the most important viruses of sugar beet in Poland. BNYVV is represented by three types, frequently A and B and rarely P, however, in Poland, type A only was recorded (2). In 2005, a survey was conducted to determine the incidence of types A and B of BNYVV in Poland. Thirty samples of sugar beet plants with rhizomania-like symptoms were collected from six fields in the western, southern, and northern areas of Poland. All samples were analyzed by double antibody sandwich-enzyme linked immunosorbent assay (DAS-ELISA) with commercial antiserum (Bio-Rad, Hercules, CA). Infection of BNYVV was found in 26 samples. The presence of the virus in these samples was confirmed by reverse transcription-polymerase chain reaction (RT-PCR). The total RNA extracted from sugar beet was tested with specific primers designed to amplify a fragment of the RNA2 for BNYVV (1). Multiplex (m) RT-PCR with two sets of primers, rhizo AF/rhizo AR and rhizo BF/rhizo BR (2), was used to distinguish A and B types of BNYVV. Two obtained mRT-PCR products were sequenced and compared with other sequences available in GenBank. A 121-nt amplicon sequence (GenBank Accession No. DQ 228872) had 100% nucleotide and amino acid sequence identity with all BNYVV type B sequences (e.g., Stourton-GenBank Accession No. AY682695) (2). A 171-nt amplicon sequence (GenBank Accession No. DQ228871) had 100% nucleotide and amino acid sequence identity with all BNYVV type A sequences (e.g., Ravenna-GenBank Accession No. AY 654282) (2). Type A was detected in 23 BNYVV-infected sugar beet plants from five fields located in western and southern Poland while type B was found in three samples from one field in northern Poland. To my knowledge, this is the first report of the natural occurrence of BNYVV type B in Poland. References: (1) A. Maunier et al. Appl. Environ. Microbiol. 69:2356, 2003. (2) C. Ratti et al. J. Virol. Methods 124:41, 2005.
First Report of Colletotrichum acutatum Causing a Leaf Spot on Myrica cerifera in Florida
Authors: Mackenzie S. J. , Takahashi L. M. , Mertely J. C. , Seijo T. E. , Peres N. A. 
Published: May 2007

Wax myrtle (Morella cerifera (synonym Myrica cerifera) (L.) Small) is a native tree used in Florida landscapes. In the summer of 2005 and spring of 2006, small necrotic spots were observed on young leaves in two commercial nurseries in central Florida. Lesions were dark brown-to-black and eventually coalesced to form large, irregular necrotic areas. Leaves with large lesions abscised prematurely, defoliating the entire plant. Conidia formed on acervuli were observed on the surface of the largest lesions and were tentatively identified as a Colletotrichum sp. Isolations from the edges of lesions were made on potato dextrose agar (PDA) after surface disinfestation of leaf pieces in 0.6% NaOCl for 30 sec. Red chromogenic colonies developed after 5 days of incubation at 24°C. Colonies produced hyaline, oblong conidia with pointed ends averaging 14 × 4 μm and were identified as Colletotrichum acutatum J.H. Simmonds (1). The sequence from internal transcribed spacer regions 1 and 2 and the 5.8s rRNA gene of the rDNA repeat for an isolate (GenBank Accession No. DQ839609) was 100% identical to sequence from the same region of 36 C. acutatum isolates in the NCBI database. These isolates came from at least 16 different hosts, including seven ornamental hosts. There were three isolates from blueberry among the matches (Accession Nos. AB219029, AJ301911, and AJ301905), and the rDNA sequence was also identical to the sequence obtained in our laboratory for a chromogenic C. acutatum isolate from blueberry. Three single-spore isolates were tested for pathogenicity on potted plants in the greenhouse. Two young shoots were spray inoculated with a suspension (1 × 106 conidia/ml) of each isolate. Shoots were covered with a plastic bag for 24 h and maintained at 26.5°C. Two shoots were sprayed with sterile water as a control and similarly covered. All isolates produced brown spots on the youngest leaves 3 to 5 days after inoculation; no symptoms developed on control shoots. The fungus was reisolated from all inoculated shoots. To our knowledge, this is the first report of C. acutatum on wax myrtle in Florida. The disease has a potential to spread and become a significant problem for the cultivation of this species in ornamental nurseries in Florida. Reference: (1) J. H. Simmonds. Qld. J. Agric. Anim. Sci. 22:437, 1965.
First Report of Iris yellow spot virus on Onion (Allium cepa) in Texas
Authors: Miller M. E. , Saldana R. R. , Black M. C. , Pappu H. R. 
Published: May 2007

Iris yellow spot virus (IYSV; family Bunyaviridae, genus Tospovirus) has emerged as a potentially devastating and widespread virus of onion. IYSV was first reported in the United States from Idaho in 1993 and has since spread to many of the onion-producing areas (1). In South America, the most recent reports of the virus on onion were from Peru and Chile (2,4). In 2005, onion plants in Uvalde County, Texas exhibited necrotic lesions on leaves typical of IYSV and disease incidence approached 100% in some fields with yield loss and quality problems. Five of six plants tested were positive for IYSV with double antibody sandwich-enzyme linked immunosorbent assay (DAS-ELISA; Agdia Inc., Elkhart, IN). In 2006, similar lesions were observed on onion plants in Uvalde County and approximately 400 km south in Hidalgo and Cameron counties. Infection points generally started as a single plant near the edge of fields and spread to plants in a 3- to 4-m area after 1 to 2 weeks. Early-season disease incidence was low in onions grown for bulbs and transplants, <10% in 2006. Disease incidence increased in some fields until the crop was harvested. Leaves of symptomatic plants were tested for IYSV and Tomato spotted wilt virus (TSWV) using DAS-ELISA, and 18 of 23 samples from the Hidalgo County area and 12 of 21 samples from the Uvalde County area were positive for IYSV. All samples tested for TSWV from these counties were negative. Virus infection in some ELISA-positive plants was verified by reverse transcription-polymerase chain reaction (RT-PCR) using primers derived from the small RNA of IYSV. The primers flanked the IYSV nucleocapsid (N) gene (5′-TAA AAC AAA CAT TCA AAC AA-3′ and 5′-CTC TTA AAC ACA TTT AAC AAG CAC-3′ (3). RT-PCR gave a PCR product of expected size (approximately 1.2 kb). The DNA amplicon was cloned and sequenced (GenBank Accession No. DQ658242). Nucleotide sequence analysis confirmed the identity of the amplicon as that of IYSV N gene and sequence comparisons with known IYSV N gene sequences showed 95 to 98% sequence identity. The primary vector of IYSV, onion thrips (Thrips tabaci), is a widespread and destructive pest of onion in south Texas. The year-to-year incidence of IYSV and the severity of the disease will probably depend on the onion thrips population levels. Bulb yield reduction could be severe during years with high thrips populations. More research is needed to determine the impact of IYSV on bulb yield in Texas, the relationship between IYSV incidence and T. tabaci population levels, and oversummering hosts. To our knowledge, this is the first known report of IYSV in Texas. References: (1) D. H. Gent et al. Plant Dis. 88:446, 2004, (2) S. W. Mullis et al. Plant Dis. 90:377, 2006, (3) H. Pappu et al. Arch. Virol. 151:1015, 2006. (4) M. Rosales et al. Plant Dis. 89:1245, 2005.