bluuebunny/crossref_metadata_2025_split huggingface dataset:
Karnal Bunt of Wheat Newly Reported from the African Continent
Authors: Crous P. W. , Van Jaarsveld A. B. , Castlebury L. A. , Carris L. M. , Frederick R. D. , Pretorius Z. A. 
Published: May 2007

In December 2000 seed harvested from wheat (Triticum aestivum L.) cultivars SST 876 and SST 825 produced under sprinkler irrigation near Douglas, Northern Cape Province, South Africa, contained a substantial amount of partially bunted kernels. Kernel embryos contained black masses of teliospores, and in many instances the endosperm was partially degraded. Teliospores were brown to dark brown, densely echinulate, 25 to 45 μm in diameter with a short mycelial fragment on some of the spores. Hyaline, smooth-walled sterile cells were also present. Teliospores were soaked in sterile distilled water for 2 days, streaked on 2% water agar plates and incubated at 22°C in the dark. Teliospores germinated after 5 days, producing 50 to 250 filiform, nonconjugating, primary basidiospores and forcibly discharged allantoid, secondary basidiospores. Based on kernel appearance, a rotten fish odor in infected grain, teliospore morphology, and germination characteristics, the pathogen was identified as Tilletia indica Mitra, the cause of Karnal bunt (1). This morphological identification was confirmed at the USDA-ARS Systematic Botany and Mycology Laboratory, Beltsville, MD. Molecular verification of 12 South African isolates was provided by the Foreign Disease-Weed Science Research Unit at Fort Detrick, MD, using real-time polymerase chain reaction with the Tin3/Tin10 T. indica-specific primer set (2). Four additional isolates were confirmed as T. indica using the same primer set as well as ITS rDNA sequencing at the Beltsville laboratory. Reference specimens were deposited at the National Fungal Collection in Pretoria, South Africa (PREM 57214), and at Beltsville (BPI 748170). At present, the mode of introduction of T. indica into South Africa, as well as its precise distribution, is not known. It appears, however, that the pathogen is restricted to the Douglas production area in the Northern Cape where quarantine measures have been taken to contain and possibly eradicate the disease. References: (1) L. A. Castlebury and L. M. Carris. Mycologia 91:121, 1999. (2) R. D. Frederick et al. Phytopathology 90:951, 2000.
A Blight Disease of Dill in California Caused by Itersonilia perplexans
Authors: Koike S. T. , Tjosvold S. A. 
Published: May 2007

In 2000, a foliar disease was observed in commercial field plantings of dill (Anethum graveolens) in coastal California. Initial symptoms consisted of a gray-green discoloration and wilting of the tips of dill leaves. As disease developed, many of the leaves discolored and collapsed, which gave the foliage a blighted appearance and made the leaves unsuitable for harvest. A fungus was consistently isolated from symptomatic leaves. Slow growing colonies were cream-colored, velutinous, and flat with minimal aerial mycelium. Mycelium was hyaline and had clamp connections. Ovoid to subglobose sporogenous cells were abundant and measured 11 to 14 × 12 to 16 μm. Spores were ballistospores that were bilaterally symmetrical, lunate, 16 to 18 × 12 to 13 μm, and germinated with hyphae or secondary ballistospores. The fungus was identified as Itersonilia perplexans Derx (1,2). Pathogenicity was tested by preparing spore suspensions (1 × 104) and spray-inoculating potted dill plants. Plants were placed in a dew chamber for 24 h and then maintained in a greenhouse (23 to 25°C). After 10 days, leaves showed symptoms similar to those observed in the field and the same fungus was reisolated. Control plants sprayed with water did not develop symptoms. Inoculations were repeated and the results were the same. In another experiment, sets of dill plants and flowers of five cultivars of potted florist's chrysanthemum (Dendranthema × grandiflorum [= Chrysanthemum × morifolium]) and one cultivar of Leucanthemum paludosum (= C. paludosum) were spray-inoculated with several dill isolates and incubated as described previously. Dill plants developed symptoms and the fungus was reisolated. However, flowers of the six chrysanthemum cultivars did not develop any petal blight symptoms. Inoculations were repeated and the results were the same. These findings are consistent with previous studies that indicate I. perplexans consists of pathogenic forms that are host-specific to either chrysanthemum and closely related Compositae or to Apiaceae plants such as dill, carrot (Daucus carota subsp. sativus), parsley (Petroselinum crispum), and parsnip (Pastinaca sativa) (1,2,3). To our knowledge, this is the first report of I. perplexans on dill in California, and also appears to be the first record of this disease in North America. References: (1) T. Boekhout. Mycol. Res. 95:135, 1991. (2) T. Boekhout et al. Can. J. Microbiol. 37:188, 1991. (3) A. G. Channon. Ann. Appl. Biol. 51:1, 1963.
First Report of a Phytoplasma Disease of Almond (Prunus amygdalus) in Lebanon
Authors: Choueiri E. , Jreijiri F. , Issa S. , Verdin E. , Bové J. , Garnier M. 
Published: May 2007

During a survey conducted in October 1999 to establish the sanitary status of stone fruits in Lebanon, almond trees with symptoms of leaf yellowing, shoot proliferation, and dieback were observed in the Bekaa region. Because such symptoms are often associated with phytoplasma infections, samples were collected for analysis by PCR using universal primers for amplification of phytoplasma ribosomal RNA genes (2). DNA was extracted from the leaf midveins and/or bark phloem tissue from nine symptomatic trees and one symptomless tree in four different orchards as well as from healthy almond trees collected in France. PCR resulted in amplification of an expected 1.8 kbp rDNA fragment from all symptomatic samples but not from the healthy or symptomless samples. For characterization, the amplified DNA was analyzed by RFLP. Even though the restriction profiles were different from those published for other phytoplasmas and in particular from those infecting almond trees in Western Europe (1), sequence analysis of the amplified DNA revealed that it belongs to the pigeon pea witches' broom cluster (PPWB) (2). This is the first report of a phytoplasma infection in Lebanon and the first report for a PPWB group phytoplasma in almond trees. References: (1) W. Jarausch et al. J. Plant Pathol. 104:17–27, 1998. (2) B. Schneider et al. 1995. Molecular and diagnostic procedures in Mycoplasmology Vol. 1, 369–380, S. Razin and J. G. Tully, eds.
Stemphylium botryosum Pathogenic on Spinach Seed Crops in Washington
Authors: du Toit L. J. , Derie M. L. 
Published: May 2007

In September 2000, symptoms typical of leaf spot caused by Cladosporium variabile were observed on a spinach (Spinacea oleracea L.) seed crop in western Washington. Dry, bleached spots (1 to 20 mm) were most abundant on lower leaves. Two isolates of C. variabile and three isolates of Stemphylium were recovered by plating surface-sterilized (0.1% sodium hypochlorite) sections of symptomatic leaf tissue onto water agar and acidified potato dextrose agar (PDA). Transfers of each isolate were made to PDA, and cultures were kept at 24 ± 2°C on a lab bench (natural day/night cycle) for 10 to 14 days. Spore suspensions (105/ml) of the isolates of C. variabile were prepared in a 0.01% solution of Tween 80. Isolates of Stemphylium produced few spores, so mycelial suspensions (105 fragments/ml) were prepared. Five 8-week-old seedlings of each of the cultivars Winter Bloomsdale and Ozarka II were inoculated per fungal isolate by atomizing the inoculum onto each seedling until all leaves were covered with a thin film of droplets (4 to 5 ml of inoculum per seedling). Plants were enclosed in plastic bags on a greenhouse bench (24 ± 3°C) for 72 h (8 h/16 h day/night). Symptoms developed within 80 h of inoculation for both isolates of C. variabile and two isolates of Stemphylium. Small (1 to 2 mm) sunken spots turned white 24 to 48 h later and became dry and bleached. Lesions caused by isolates of Stemphylium enlarged and coalesced more rapidly than lesions caused by C. variabile, and were more irregular and usually not delimited by the thin brown margin typical of lesions caused by C. variabile. The differences in symptoms were consistent on both spinach cultivars. Symptoms were not observed on non-inoculated control plants nor on plants inoculated with the third isolate of Stemphylium. C. variabile and Stemphylium were reisolated from symptomatic leaf tissue. Colony morphology, conidiophores, and conidia of the pathogenic Stemphylium isolates were similar to those of pathogenic isolates of Stemphylium botryosum obtained from spinach plants in California (2). This is the first report of S. botryosum as a foliar pathogen of spinach seed crops in Washington. Although Correll et al. (1) noted Stemphylium to be damaging on mature spinach plants grown for seed production, S. botryosum may not have been diagnosed previously on spinach seed crops in Washington because of the similarity of symptoms caused by S. botryosum and C. variabile. S. botryosum was recently reported as a foliar pathogen of spinach in California (2). References: (1) J. C. Correll et al. Plant Dis. 78:653, 1994. (2) S. T. Koike et al. Plant Dis. 85:126, 2001.
First Report of Cryptocline taxicola Infecting Pacific Yew (Taxus brevifolia) in Eastern North America
Authors: Vujanovic Vladimir , St-Arnaud Marc 
Published: May 2007

To our knowledge, this is the first report of Cryptocline taxicola (Allesch.) Petrak (Coelomycetes) on Pacific yew (Taxus brevifolia Nuttall) and the first observation of the fungus infecting living needles. C. taxicola is known to occur on needles of Taxus baccata in Europe (on T. baccata var. fastigiata) and North America (Vermont) (on T. baccata var. canadensis) (2). In August 1999 and 2000, chlorotic and necrotic current and second-year needles of Pacific yew were observed to have fruiting bodies, sometimes greater than 400 per needle, on the upper surface. Acervuli were circular to subcircular, yellowish, surrounded by brown circles, subcuticular to intraepidermal, at first covered, later exposed by the fissure of the cuticule, and 150 to 350 μm wide. Hyphae in host tissue were septate, brownish, and 3 to 4.5 μm in diameter. Conidiophores were phialidic, cylindrical, hyaline, 10 to 20 × 2.5 to 4.5 μm. Mature conidia were ellipsoidal to oval, truncate at the base, obtuse at the apex, hyaline to slightly pigmented, 8 to 17 × 4 to 5 μm. From these symptomatic needles, C. taxicola was often isolated (>85%) on potato dextrose agar. Koch's postulates were completed for C. taxicola by spraying current-year living needles, on one twig of each of separate plants (five) of T. brevifolia with a conidial suspension of 4 × 103 conidia per ml. Five control twigs were sprayed with sterile, distilled water. Twigs were covered with black sterile plastic bags and incubated outdoors for 24 h, when the bags were removed. Within 3 weeks, inoculated needles exhibited chlorotic and necrotic symptoms similar to those originally observed, but symptoms were never observed on control twigs. The fungus was reisolated (91%) only from the symptomatic needles. T. brevifolia trees growing in the Montreal Botanical Garden (Quebec, Canada) are clones originating from the Pacific Coast of the United States. We found that Pacific yew was colonized more frequently on the dry rock outcrops in the Alpine and Chinese Garden tree plantations. We believe that inappropriate stand selection, unfavorable humid conditions, and a thin organic soil layer may predispose Pacific yew to infection by this fungal species. A similar effect has been reported in Europe (1) for Cryptocline pseudotsugae causing serious levels of disease in a Pseudotsuga menziesii plantations. References: (1) T. L. Cech. Forstschutz Aktuell. 25:13, 2000. (2) G. Morgan-Jones. Can. J. Bot. 51:309, 1973.
First Report of Meloidogyne partityla on Pecan in New Mexico
Authors: Thomas S. H. , Fuchs J. M. , Handoo Z. A. 
Published: May 2007

For several years, decline was observed in mature pecan (Carya illinoensis (F.A. Wangenheim) K. Koch) trees in an orchard in Dona Ana County, New Mexico despite normal fertilization and irrigation practices. Affected trees were growing in sandy soil in two widely separated irrigation terraces and exhibited chlorosis of foliage and substantial die-back of branches in the upper canopy. Examination of feeder roots revealed the presence of numerous small galls and egg masses, with root-knot nematode females often visibly protruding from root tissue. Attempts to culture the nematode on tomato (Lycopersicon esculentum Mill. ‘Rutgers’) were unsuccessful. Females and egg masses were collected from fresh pecan roots and sent to the USDA Nematology Laboratory in Beltsville, MD, in October 2000, where specimens were identified as Meloidogyne partityla Kleynhans (1) based on morphological examination. This is the first report of M. partityla from New Mexico, and the second report of this nematode outside South Africa. Starr et al. (2) first reported M. partityla from pecan in the United States in 1996, after recovering the nematode from five orchards in Texas. In their study, the host range of M. partityla was limited to members of the Juglandaceae, which may explain the inability of the New Mexico population to reproduce on tomato. Additional information is needed regarding distribution of this nematode within pecan-growing regions throughout North America. References: (1) K. P. N. Kleynhans. Phytophylactica 18:103, 1986. (2) J. L. Starr et al. J. Nematol. 28:565, 1996.
Detection of Cucurbit Yellow Vine Disease in Squash and Pumpkin in Massachusetts
Authors: Wick R. L. , Lerner J. , Pair S. D. , Fletcher J. , Mitchell F. , Bruton B. D. 
Published: May 2007

Commercial plantings of summer squash in Charlemont, Franklin County, MA, were decimated in 1999 by 100% incidence of a yellowing disease resembling cucurbit yellow vine disease (CYVD) (1). Both plantings were established in the same field during the third week of May, one with transplants and the second by direct-seeding. Each planting consisted of four 30-m rows each of yellow zucchini (Cucurbita pepo cv. Gold Rush), summer squash (C. pepo cv. Seneca Prolific), and zucchini (C. pepo cv. Condor). Crops were produced organically and pyrethrum was used to control a high infestation of squash bugs, Anasa tristis (De Geer) (Heteroptera:Coreidae), a putative vector of CYVD (3). Just prior to fruit set, during the first two weeks of June, plants began showing symptoms of foliar chlorosis, plant stunting, or both. All of the plants in the field eventually wilted and collapsed. Cross-sections of the below-ground stem and primary root revealed a honey-brown phloem discoloration and healthy appearing xylem, symptoms characteristic of CYVD. Plants yielded marketable fruit for only about 1 week. When plant samples were tested by polymerase chain reaction (PCR) with CYVD bacterium specific primers (2), a band of the expected size for the CYVD bacterium, identified as Serratia marcescens based on 16s rDNA and groE sequence analyses (4), was amplified in every case. Since all plant samples collected were symptomatic and PCR positive for S. marcescens, asymptomatic greenhouse plants were run simultaneously as a control. All control plants tested negative. A third planting, similar to the two disease-affected plantings and containing the same three squash cultivars from the same seed lot, was established at about the same time approximately 3 km away. No symptoms of CYVD occurred at this site, further evidence that the pathogen is not seed-borne (1). Furthermore, squash bugs were not observed in this field. In 2000, the disease was observed in a planting of ‘Atlantic Giant’ pumpkin in Erving, Franklin County, MA, and confirmed by PCR. Until now, CYVD has been reported only in the states of Oklahoma, Texas, and Tennessee. Confirmation of the disease in Massachusetts significantly increases the known geographical range of CYVD to include the New England area. References: (1) B. D. Bruton et al. Plant Dis. 82:512–520, 1998. (2) U. Melcher et al. Phytopathology 89:S95, 1999. (3) S. D. Pair et al. Pages 145–148 in: Proc. 19th Ann. Hort. Conf., Okla. State Univ. (4) J. Rascoe et al. Phytopathology 90:S63, 2000.
First Report of Aflatoxin in Dried Yam Chips in Benin
Authors: Bassa S. , Mestres C. , Champiat D. , Hell K. , Vernier P. , Cardwell K. 
Published: May 2007

Dried yam (Dioscorea spp.) chips are widely consumed in Bénin but are often attacked by molds. Invasion of food by Aspergillus flavus may lead to aflatoxin contamination. We report here the result of a survey on the sanitary quality of dried yam chips in Bénin. During July and August 2000, 50 dried yam chips samples were collected from different points in the marketing chain; 10 samples were collected from each of 5 stages: producers, wholesalers, retailers, dried yam-based food sellers and consumers. Aflatoxin content was assayed by the bio-luminescence method (1) after methanol/water extraction. Aflatoxins were detected in all dried yam chip samples, with levels ranging from 2.2 to 200 ppb and a mean value of 14 ppb. An aflatoxin concentration higher than the European Union's maximum residue limit (MRL) of 4 ppb was found in 98% of the samples (N = 50), while 6% had an aflatoxin concentration higher than the World Health Organization's MRL of 20 ppb. Molds were analyzed from two samples, each with aflatoxin levels around 5 ppb, on colony unit medium specific for A. flavus (2). Aspergillus spp. were detected in the inner part of dried yam chips of both samples, with a mean level of 9,000 CFU/g. Fusarium colonies were also present but were not identified to species. References: (1) D. Champiat and J. Larpent. Bio-chimie-luminescence: Principes et Applications. Masson, Paris, France. 1993. (2) P. J. Cotty. Mycopathologia 125:157, 1994.
First Report of Alfalfa mosaic virus in Physostegia virginiana
Authors: Cardin L. , Onesto J.-P. , Moury B. 
Published: May 2007

Physostegia virginiana Benth. (false dragon head) is a perennial plant from the family Lamiaceae cultivated as an ornamental in gardens and for cut-flower production. In 2000, stunting of plants and yellow-to-brown ringspots on leaves were observed in cut-flower production in the Alpes Maritimes Department (southeast France). These symptoms greatly decreased the commercial value of the stems. The disease was attributed to Alfalfa mosaic virus (AMV) because extracts of infected plant tissues revealed typical bacilliform particles by electron microscopy, produced symptoms typical of AMV after inoculation of a range of previously described test plants (1), and reacted positively in enzyme-linked immunosorbent assays (ELISA) with antibodies raised to a tomato strain of AMV (from G. Marchoux, INRA, France). After isolation from single local lesions on Vigna unguiculata, the AMV isolate was multiplied in cv. Xanthinc tobacco, where it induced local and systemic ringspot symptoms. Infected Xanthinc plants served as sources of inocula for subsequent mechanical- and aphid (Myzus persicae)-transmission tests to healthy seedlings of P. virginiana (seeds from the botanic garden of Nancy, France; 36 plants for each inoculation procedure). Chlorotic and necrotic local lesions were observed in 25% of mechanically inoculated plants. Three months after inoculation, uninoculated leaves of all mechanically inoculated plants and 30.5% of aphid-inoculated plants tested positive for AMV based on ELISA. During the first year after inoculation, less than 10% of infected plants showed typical systemic symptoms. This proportion reached 40% during the second year. Recently, we observed similar symptoms in P. virginiana plants cultivated in public gardens in Intercourse (Pennsylvania), Toronto (Ontario, Canada) and Montreal (Quebec, Canada). Using ELISA, AMV was detected in symptomatic plants from these three additional locations. Reference: (1) L. Cardin and B. Moury. Plant Dis. 84:594, 2000.
First Report of White Fir Dwarf Mistletoe on Mountain Hemlock
Authors: Mathiasen R. 
Published: May 2007

White fir dwarf mistletoe (Arceuthobium abietinum Engelm. ex Munz f. sp. concoloris Hawksw. & Wiens) is a serious and common pathogen of white fir (Abies concolor (Gord. & Glend.) Hildebr.), grand fir (A. grandis (Dougl. ex D. Don) Lindl.), and Low's fir (A. lowiana (Gord.) A. Murr.) in the western United States (1). In August 2002, this dwarf mistletoe was observed parasitizing mountain hemlock (Tsuga mertensiana (Bong.) Carr.) growing among severely infected grand fir near the trailhead to Cabot Lake in the Mount Jefferson Wilderness Area, Oregon at 44°34′27″N, 121°43′43″W, elevation 1,340 m. Only 2 of 27 mountain hemlocks observed in this area were infected. One tree had four infections, and one tree had two infections. Several fully developed male plants were found on one of the infected branches of mountain hemlock and were morphologically similar to those growing on the nearby grand fir. Other dwarf mistletoes that commonly parasitize mountain hemlock (Arceuthobium tsugense subsp. mertensianae and Arceuthobium laricis) were not observed in the area. In addition, white fir dwarf mistletoe can be distinguished from these mistletoes by its larger, yellowish shoots (1). Specimens of the mistletoe from mountain hemlock have been deposited in the Deaver Herbarium, Northern Arizona University, Flagstaff. To my knowledge, this is the first report of white fir dwarf mistletoe on mountain hemlock (1). Reference: (1) F. Hawksworth, and D. Wiens. Dwarf mistletoes: biology, pathology, and systematics. USDA Agric. Handb. 709, 1996
First Report of the Cyst Nematode (Globodera tabacum) Complex on Flue-Cured Tobacco in Spain
Authors: Espárrago G. , Blanco I. 
Published: May 2007

The Globodera tabacum complex infects tobacco (Nicotiana tabacum L.) fields in the United States. In August 2001, plants of flue-cured tobacco cv. K326 from a field of the La Vera Region of Spain displayed a premature wilting and yellowing of foliage, but the roots looked healthy. In the laboratory under the microscope, nematode cysts were observed on the roots. At harvest in September 2001, soil and root samples were collected to identify the nematode and to quantify the population in the soil. Identification of the nematode was based on morphological characteristics of second-stage juveniles collected from cysts and perineal patterns of cysts recovered from the roots (2). Cysts were collected from roots, and second-stage juveniles were extracted from crushed cysts. The nematode population was extracted from the soil and quantified as described by Barker (1). The nematode population was identified as Globodera tabacum. Soil density of the nematode was 5,307 cysts per liter of soil, 64,286 eggs per liter of soil, and 16,071 second-stage juveniles per liter of soil. To our knowledge, this is the first report of G. tabacum complex in Spain. References: (1) K. R. Barker. Nematode extraction and bioassays. Page 19 in: An Advanced Treatise on Meloidogyne. Vol II, Methodology. K. R. Barker, C. C. Carter, and J. N. Sasser, eds. North Carolina State University Graphics, Raleigh, 1985. (2) R. H. Mulvey and A. Morgan Golden, J. Nematol. 15:1, 1983.