bluuebunny/crossref_metadata_2025_split huggingface dataset:
First Report of Phoma exigua as a Pathogen of Salal (Gaultheria shallon) in British Columbia, Canada
Authors: Shamoun S. F. , Zhao S. 
Published: May 2007

Salal (Gaultheria shallon Pursh.) is an ericaceous, evergreen, and rhizomatous shrub that competes for nutrients and moisture with young conifers in low elevation, coastal British Columbia (BC). A survey was conducted on southern Vancouver Island, BC during the summer of 1999 to find fungal pathogens of salal that might serve as biocontrol organisms (3). Phoma exigua Desmaz. (isolate PFC2705) near Parksville, BC proved to be pathogenic on salal. Identification of PFC2705 at the Centraalbureau voor Schimmelcultures was based on morphology and ITS sequences (GenBank Accession No. AY927784). Pathogenicity was determined with 24 salal seedlings (3-month-old) by inoculating with mycelial suspensions (20% v/v) or conidial suspensions (1 × 106 conidia per ml in 0.5% potato dextrose broth). Inoculated seedlings were placed in plastic bags and incubated in a greenhouse (16 to 23°C with natural light). Plastic bags were removed after 2 days. Initial disease symptoms were observed 2 days after inoculation. Brown, sunken lesions appeared on the surface of young leaves and stems and extended quickly. All seedlings were killed within 14 days. Twelve control plants showed no disease symptoms. With diseased salal leaves incubated at 23°C with 12-h fluorescent light/dark and 100% relative humidity, pycnidia appeared on leaf surfaces within 5 days. Conidia were hyaline, ellipsoid, one-celled, sometimes two- to three-celled, 2.5 to 3.8 × 5 to 12.5 μm, with a rounded base; the colony was gray or dark gray on potato dextrose agar after 5 to 7 days. Reisolation from the inoculated diseased leaves produced a mycelial colony that shared the same growth and morphological characteristics as the initial isolate. Phyllosticta gaultheriae Ellis & Everh., a widely reported foliar pathogen of salal, is distinct morphologically from P. exigua (1). To our knowledge, this is the first report of P. exigua as a pathogen of salal in Canada (2). A voucher specimen has been deposited at the Pacific Forestry Center Herbarium (DAVFP No. 28735). References: (1) J. Bissett and S. J. Darbyshire. No. 275 in: Fungi Canadenses, 1984. (2) D. F. Farr et al. Fungi on Plants and Plant Products in the United States. The American Phytopathological Society. St. Paul. MN, 1989. (3) S. F. Shamoun et al. Can. J. Plant Pathol. 22:192, 2000.
First Report of Rhizoctonia solani AG-4 and AG-2-2 on Lupinus angustifolius in Canada
Authors: Chang K. F. , Hwang S. F. , Gossen B. D. , Howard R. J. , Lopetinsky K. , Olson M. 
Published: May 2007

Narrow-leaved lupine (Lupinus angustifolius L.) is grown as a grain legume crop in Australia and Europe where it is used as feedstock in the livestock and aquaculture industries. During July 2003, a stem rot disease was observed in narrow-leaved lupine (cv. Arabella) plants in a research plot at the Crop Diversification Centre North (CDCN), Edmonton, Alberta, Canada. The disease was also found on cv. Rose at the CDCN and cv. Arabella in experimental fields near Devon, Ellerslie, and Westlock, Alberta during the late spring of 2004. Diseased plants showed dark brown-to-black stems with sunken and constricted lesions at the soil level. Young leaves became shrunken and twisted and seedlings collapsed. Rhizoctonia solani was consistently isolated from lesions on taproots and basal stems of diseased plants. Colonies of cream-colored mycelia grew close to the surface of potato dextrose agar (PDA). Most sclerotia formed inside the medium. Agar disks (1 cm in diameter) of isolates LP-11Bb, LP-24C, and LP-25C were attached to the opposite sides of basal stems (180° apart) of 1-month-old lupine seedlings (cv. Arabella). Inoculated plants were incubated for 2 days in black plastic bags under a greenhouse bench at approximately 20°C. All isolates caused brown lesions on the lower stems (extending up to 7 cm above ground level), girdling, and root rot. Plants wilted within 7 to 10 days after inoculation, and aerial mycelia appeared on the basal stems. R. solani was reisolated from the infected crown tissues using PDA to complete Koch's postulates. The isolates were paired with AG tester strains of R. solani. Isolates LP-11Bb and LP-24C were identified as AG-4 while isolate LP-25C was identified as AG-2-2. In another trial, eight isolates of R. solani (unknown AG types) were tested for virulence on L. angustifolius cv. Arabella using the inoculation method described above. All isolates were pathogenic, and disease severity that was based on a 0 to 4 scale ranged from 2.7 to 3.2. The most virulent strain was LP-24C, which caused a 77% loss in fresh weight compared with the noninoculated control plants. R. solani AG-8 is associated with Rhizoctonia disease of lupine in Australia (1) and also causes bare patch disease of wheat. To our knowledge, this is the first report of R. solani on lupine in Canada. This disease could have a significant impact on the commercial production of lupine in Alberta. Reference: (1) M. W. Sweetingham et al. Pages 466–486 in: Advances in Lupin Disease Management in Australia. Proc. Int. Lupin Conf., 8th. G. D. Hill, ed. International Lupin Association, Canterbury, New Zealand, 1999.
First Report of Fusarium oxysporum f. sp. canariensis Causing Fusarium Wilt on Phoenix canariensis in Sardinia, Italy
Authors: Migheli Q. , Balmas V. , Muresu M. , Otgianu L. , Fresu B. 
Published: May 2007

During the summer of 2004, severe symptoms of wilt were observed on 25-year-old plants of Canary Island Date Palm (Phoenix canariensis Hort. ex Chabaud) located at the seafront of Poetto Beach in the metropolitan area of Cagliari, southern Sardinia, Italy. Symptoms consisted of one-sided leaflet dieback of fronds, necrotic and brown streaking on the lower rachis base of older leaves, and necrosis of vascular bundles. Of 300 palms, there were 90 plants that were symptomatic and at least 4 were dead. Fusarium oxysporum Schlecht. emend. Snyder & Hansen has been consistently isolated from surface-sterilized petioles of symptomatic leaves sampled from affected palms. The opportunistic pathogen Gliocladium vermoesenii (Biourge) Thom was frequently associated with F. oxysporum in diseased samples, confirming previous reports of a disease complex between these two fungi (1). Five F. oxysporum isolates collected from different symptomatic plants were analyzed with a polymerase chain reaction (PCR)-based assay with the F. oxysporum f. sp. canariensis-specific primers HK66 + HK67 (2). The thermocycling schedule was as follows: initial denaturation at 94°C for 5 min, 35 cycles each of 1 min at 94°C, 1 min at 62°C, 1 min and 30 s at 72°C, followed by a final extension at 72°C for 5 min. A 567-bp PCR product of the expected size was obtained from all tested F. oxysporum isolates, allowing their identification as F. oxysporum f. sp. canariensis. This disease was previously reported from other Italian regions (Sicily, Marche, and Liguria), but its presence in Sardinia should be considered carefully since it represents a serious threat to ornamental palms, which are abundant all over the island. The source of this outbreak may be related to the importation of seedlings from areas where F. oxysporum f. sp. canariensis is widely established. References: (1) H. D. Ohr. Pink rot (Gliocladium Blight). Pages 24–25 in: Diseases and Disorders of Ornamental Palms. A. R. Chase and T. K. Broschat, eds. The American Phytopathological Society, St. Paul, MN, 1991. (2) T. R. Plyler et al. Phytopathology 89:407, 1999.
First Report of Bean pod mottle virus in Soybean in Iran
Authors: Shahraeen N. , Ghotbi T. , Salati M. , Sahandi A. 
Published: May 2007

Soybean (Glycine max (L.) Merr.) has been increasing in importance and acreage for the past 5 years in Iran and is now planted on approximately 108,000 ha. Previous surveys in Iran of viruses infecting soybean failed to identify Bean pod mottle virus (BPMV), but the incidence of other common viruses of soybean in the field has been reported (1). During October 2004, symptoms characteristic of those caused by BPMV including mosaic, puckering of trifoliate leaves, and delayed maturity of stems or green stems were observed in soybean fields in the Takhti Mahaleh, Versen, and Hashemabad areas located in the Gorgan Province. Sporadic incidence of plants infected with BPMV has been usually of minor importance to growers. Symptoms were often overlooked or considered to be physiological disorders. A visual assessment was made to determine incidence of green stem in the commonly grown soybean cv. Sahar. Forty soybean plants showing symptoms of crinkling, mottling, green stem, and retaining green leaves were sampled by collecting one trifoliate leaf near the top of the plant. All samples were tested in parallel for BPMV using double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). BPMV was detected in 40% of the samples. Seven of the samples shown to be infected with BPMV using DAS-ELISA were mechanically (2) transferred to soybean seedlings in the greenhouse. These plants developed systemic mottle symptoms typical of those caused by BPMV and tested positive for BPMV using DAS-ELISA. The distribution of BPMV within soybean-growing regions, exploration of potential virus reservoirs, and economic impact of this virus have yet to be determined. There is no published report on the presence of potential BPMV vectors including the bean leaf beetle (Cerotoma trifurcata) from soybean fields in Iran. To our knowledge, this is the first report of BPMV in Iran. References: (1) A. R. Golnaraghi et al. Plant Dis.88:1069, 2004. (2) R. Louie et al. Plant Dis.84:1133, 2000.
First Report of Powdery Mildew Caused by Leveillula taurica on Tomato and Pepper in Bolivia
Authors: Correll J. C. , Villarroel M. I. , McLeod P. J. , Cazon M. I. , Rivadeneria C. 
Published: May 2007

Chlorotic and necrotic lesions typical of powdery mildew caused by L. taurica were observed in several tomato (Lycopersicon esculentum) and pepper (Capsicum annuum) fields in Santa Cruz State, Bolivia near the town of Mairana during September 2004. The tomato cultivars affected were Santa Clara, Superman, and Cool 45. Symptoms included bright yellow chlorotic lesions or brown necrotic lesions on different age leaves. Examination of samples collected from several fields revealed sporulation of L. taurica on abaxial leaf surfaces. The fungus had branched conidiophores, a tapered or pyriform apical conidium, with other conidia being more cylindrical (1,2). Conidial size was approximately 60 × 18 μm. Only the Oidiopsis stage was observed. Disease severity was high and caused a significant amount of leaf necrosis and partial defoliation on tomato. Only sporadic lesions were observed on pepper cv. YoloWonder and no significant foliar damage was observed. The growing region receives approximately 75 mm of rainfall annually with most of the rainfall occurring between October and April. Thus, powdery mildew was observed near the end of the normal 5-month dry season. It is likely that the disease has been in the region for some time based on observations from field personnel. Although reported from several other South American countries, to our knowledge, this is the first report of this disease in Bolivia. References: (1) H. J. Boesewinkel. Bot. Rev. 46:167, 1980; (2) J. C. Correll et al. Plant Dis. 71:248, 1987.
Verticillium Wilt Incited by Verticillium dahliae in Eggplant Grafted on Solanum torvum in Italy
Authors: Garibaldi A. , Minuto A. , Gullino M. L. 
Published: May 2007

Eggplant cultivars grafted on rootstocks resistant to root-knot nematodes (Meloidogyne spp.) are increasingly grown in Italy to reduce nematode infection. During the winter of 2003-2004, eggplants (cv Black Bell and Mirabell) grafted on the nematode-resistant rootstock Solanum torvum were observed with symptoms of a wilt disease in several greenhouses in Sicily (southern Italy). The vascular tissue in stems of affected plants appeared brown. These plants were stunted and developed yellow leaves with brown or black streaks in the vascular tissue. The wilt appeared in several greenhouses at a very low incidence (0.01 to 0.05%). Later, during the fall of 2004, disease incidence was approximately ten times greater in the same greenhouses on new crops. Verticillium dahliae was consistently and readily isolated from symptomatic vascular tissue of the rootstock (S. torvum) and the scion (cv Black bell) when cultured on potato dextrose agar (PDA) (1). Healthy, 50-day-old plants of S. torvum and eggplant (cv. Black Bell) were separately inoculated by root dip with a conidial suspension (1 × 107 CFU/ml) of two isolates of V. dahliae obtained from the rootstock and the scion of the infected grafted plants and with a known pathogenic isolate of V. dahliae from nongrafted eggplant. Noninoculated S. torvum and eggplant served as control treatments. Plants (30 per treatment) were grown in a glasshouse at temperatures ranging between 12 and 41°C (weekly average 15 to 36°C) and relative humidity ranging between 36 and 99% (weekly average 54 to 95%). The first wilt symptoms and vascular discoloration in the roots, crowns, and veins developed 26 and 21 days after inoculation on S. torvum and eggplant, respectively. Seventy-two days after inoculation, 20, 26, and 27% of S. torvum plants and 97, 100, and 87% of the eggplants showed symptoms caused by V. dahliae isolates obtained from the scion of diseased grafted plants, the rootstock of diseased grafted plants, and nongrafted eggplants, respectively. Noninoculated plants remained healthy. To our knowledge, this is the first report in Italy of Verticillium wilt on eggplant grafted on S. torvum rootstocks under commercial conditions. Use of eggplant grafted on the nematode-resistant rootstock of S. torvum presents an interesting opportunity to control the root-knot nematode but has to be carefully considered when dealing with soils severely infested by V. dahliae. Reference: (1) G. F. Pegg and B. L. Brady. Verticillium Wilts. CABI Publishing, Wallingford, UK, 2002.
First Report of Sapwood Rot of Peach Caused by Schizophyllum commune in China
Authors: Dai Y. C. 
Published: May 2007

Peach,Prunus persica (L.) Batsch, is widely cultivated in gardens and plantations in northern China. During the summer of 2002, a severe sapwood rot of 5-year-old saplings was observed in a commercial nursery near Tieling, Liaoning Province, northeast China, 42°24′N, 123°55′E. More than 80% of saplings were infected and 35% were dead. Leaves were chlorotic or necrotic and dry, and wood discoloration and white sapwood rot were observed in cross sections of infected trees. Basidiocarps on the diseased trees were identified as Schizophyllum commune Fr.:Fr. (2); on potato dextrose agar (PDA), isolates obtained from decayed wood yielded colonies characteristic of S. commune as well (3). Basidiocarps had been initiated in early June and sometimes fruited over the entire length of the stem and some parts of major branches. Liaoning Province had an abnormally cold winter in 2001 and freeze injury may have predisposed the saplings to S. commune. In addition to P. persica, P. pseudocerasus Lindl. and P. salicina Lindl. were symptomatic. Pathogenicity was confirmed by inoculation of healthy saplings of peach in the greenhouse. Saplings were subjected to freezing for 1 week and 15 were inoculated with S. commune and five were inoculated with agar. Mycelial plugs, grown for 9 days on PDA, were the inoculum for stem wounds. The inoculated area was then covered by wet cotton and wrapped in Parafilm for 2 weeks. Symptoms developed on 14 of 15 inoculated saplings after 6 weeks. Symptoms progressed from chlorotic leaves to decayed bark and wood. After 10 weeks, 11 saplings were dead. The pathogen was reisolated from 13 of 14 symptomatic saplings, and fruiting bodies of S. commune developed on eight saplings. Control saplings remained symptomless. In China and the United States, S. commune is widely reported as a saprotroph or opportunistic pathogen of many woody angiosperms (4) and some gymnosperms (1). To our knowledge, this is the first report of S. commune causing sapwood rot of P. persica in China. References: (1) D. F. Farr et al. Fungal Databases, Systematic Botany and Mycology Laboratory. On-line publication. ARS, USDA, 2005. (2) J. P. Lindsey et al. Bibl. Mycol. 63:1, 1978. (3) M. K. Nobles. Can. J. Res. Sect. C Bot. Sci. 26:281, 1948. (4) F. L. Tai. Sylloge Fungorum Sinicorum. Science Press, Beijing, 1979.
Six Races of Venturia inaequalis are Found Causing Apple Scab in Spain
Authors: Martínez-Bilbao A. , Murillo J. 
Published: May 2007

Apple scab, caused by the ascomycete Venturia inaequalis, is an important disease of apple (Malus domestica) worldwide and is generally managed with intensive applications of fungicides or, for specific markets, by planting of resistant cultivars. Currently, eight races of the pathogen have been defined on the basis of their ability to overcome sources of resistance used by plant breeders (2). We undertook the identification of apple scab races present in Spain as a necessary step for the deployment of resistant cultivars. Spore suspensions (2.5 × 105 spores per ml) were prepared from fresh lesions of apple scab collected from apple trees in commercial or domestic orchards located in the northeastern Spanish provinces of Gerona, Guipúzcoa, and Navarra. To identify races 1 to 7, the suspensions were used to inoculate cv. Gala and six differential apple clones with five replicates. Cultivar Gala was used as a universal susceptible control. The differential apple clones included X2250, X2253 (Geneva), X2249, X2225, X2596 (Prima), and X6518 (M. floribunda 821) (1,4). All leaves were assessed on each inoculated shoot 17 days after inoculation, and the type of symptoms were scored using the scale of Chevalier et al. (3). Sporulation was evaluated on seven replicate leaf discs (1 cm in diameter) for each combination of inoculum and plant host (4). All the inocula tested produced typical apple scab symptoms and sporulation (>106 conidia per cm2) on cv. Gala. Races 2, 3, 5, and 6 were identified on the basis of the elicitation of typical disease symptoms with abundant sporulation (>3 × 106 conidia per cm2) on clones X2250, X2253, X2225, and X2596, respectively. Races 2 and 6 were present in inocula from Gerona, Guipúzcoa, and Navarra, whereas races 3 and 5 were identified only in an inoculum from Tudela, Navarra. An inoculum from La Tallada, Gerona, was assigned to race 1 because it produced typical disease symptoms and sporulation only on cv. Gala, while the differential clones were scored as resistant. In Santesteban, Navarra, a monosporic isolate of V. inaequalis, designated VIP28, was obtained in the field from a single lesion in a 2-year-old tree of clone 2.1.1, which is resistant to race 1. VIP28 produced lesions typical of weak virulence in clone X6518 and produced a significant degree of sporulation (0.8 × 106 conidia per cm2), whereas the differential clones for races 2 to 6 were scored as resistant, indicating that this isolate can be classified as race 7 (1). To our knowledge, this is the first report of races of V. inaequalis present in Spain. References: (1) G. Bénaouf and L. Parisi. Phytopathology 90:236, 2000. (2) V. G. M. Bus et al. New Phytol. doi:10.1111/j.1469-8137.2005.01395.x, 2005. (3) M. Chevalier et al. Plant Pathol. 40:249, 1991. (4) L. Parisi et al. Phytopathology 83:533, 1993.
First Report of Tobacco as a Natural Host of Tomato yellow leaf curl virus in Spain
Authors: Font M. I. , Córdoba C. , García A. , Santiago R. , Jordá C. 
Published: May 2007

Two begomovirus species, Tomato yellow leaf curl Sardinia virus (TYLCSV) and Tomato yellow leaf curl virus (TYLCV), have been identified as causal agents of tomato yellow leaf curl disease (TYLCD) in Spain. TYLCSV was reported in Spain in 1992 and TYLCV in 1997 on tomato crops (3). TYLCV was also reported in common bean (Phaseolus vulgaris L.) and pepper (Capsicum annuum L.) crops in southern Spain in 1997 and 1999, respectively. During the summer of 2004, symptoms of yellowing, crumpling, and necrosis of new leaves were observed sporadically in young, field-grown tobacco (Nicotiana tabacum L.) plants in the Badajoz Province. These tobacco plants were next to tomato crops where TYLCV was detected for the first time in Badajoz in 2003. In September 2004, four symptomatic tobacco plants were selected for double antibody sandwich enzyme linked immunosorbent assay (DAS-ELISA) and polymerase chain reaction (PCR) identification analyses. Serological analyses were carried out in two repetitions and with the following polyclonal antisera: Potato virus Y (PVY) (Loewe Biochemica, Sauerlach, Germany); Tobacco mild green mosaic virus (produced in our laboratory); Tobacco mosaic virus (BIO-RAD, Marnes-La-Coquette, France); and Tomato spotted wilt virus (Loewe Biochemica). A simplified method of duplex PCR was used for a rapid, sensitive, and simultaneous detection of TYLCSV and TYLCV (2). Mixed infections of PVY and TYLCV were detected in all four tobacco samples tested. TYLCV infection was confirmed using the primer pair TY-1/TY-2 specific for the coat protein (CP) gene of begomoviruses (1). The CP fragment was digested with the restriction enzyme AvaII, and the pattern obtained corresponded to that obtained from TYLCV-infected tomato that served as a positive control. Two PCR products from different tobacco samples were sequenced and both showed 100% identity with the corresponding region (Almería) of TYLCV (GenBank Accession No. AJ489258) and 99% with TYLCV-Mild (Spain) (GenBank Accession No. AJ519441), confirming the diagnosis. The symptoms observed in the tobacco plants can not be attributed solely to TYLCV since the virus was present in a mixed infection with PVY. However, tobacco infected with TYLCV may serve as an important alternate host for TYLCV in the tomato cropping system. To our knowledge, this is the first report of N. tabacum as a natural host of TYLCV in Spain. References: (1) G. P. Accotto et al. Eur. J. Plant Pathol. 106:179, 2000. (2) P. Martínez-Culebras et al. Ann. Appl. Biol. 139:251, 2001. (3) J. Navas-Castillo et al. Plant Dis. 81:1461, 1997.