Perpetuation of Powdery Mildew Infection and Identification of Erysiphe australiana as the Crape Myrtle Pathogen in Mid-Tennessee

The fungus Erysiphe lagerstroemiae is commonly known as the powdery mildew pathogen in crape myrtle (Lagerstroemiae indica) in the United States, and Erysiphe australiana is the powdery mildew pathogen reported in Japan, China, and Australia. The teleomorph often used to identify powdery mildew fungi rarely develops in crape myrtle, and in our observations, ascocarps never formed. Our study showed that the crape myrtle pathogen overwintered as mycelia on dormant buds. The internal transcribed spacer (ITS) regions of rDNA and the intervening 5.8S rRNA gene were amplified using standard polymerase chain reaction (PCR) protocols and the universal primer pairs ITS1 and ITS4. PCR products were analyzed by electrophoresis in a 1.5% agarose gel and sequenced, and the ITS PCR product was 666 bp from ITS1/ITS4 and 704 bp from ITS1-F/ITS4. BLAST analysis of the sequence of the PCR products showed identical similarity with E. australiana reported in Japan, China, and Australia. Comparison of ITS sequences with information in the GenBank on other powdery mildew fungi showed a closest alignment (93% similarity) to Erysiphe juglandis that infects walnut. Specific primers for E. australiana were developed and evaluated for use as diagnostic tools. Out of 12 specific primer pairs evaluated, four primer pairs and four double primer pairs were highly specific to E. australiana and did not amplify Erysiphe pulchra of dogwood, Erysiphe syringae of common lilac, Erysiphe circinata of maple, or Phyllactinia guttata of oak. The E. australiana-specific primers amplified 16 samples of crape myrtle powdery mildew collected from diverse locations in mid-Tennessee. These results clearly showed that the crape myrtle powdery mildew in mid-Tennessee was caused by E. australiana. Specific primers reported in this article provide a diagnostic tool and may be used to confirm the identity of crape myrtle powdery mildew pathogen in other areas in the United States and wherever the disease occurs.

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First Report of Powdery Mildew Caused by Podosphaera (Sphaerotheca) fusca on Euryops pectinatus in North America

Plant Disease ◽

10.1094/pdis.2000.84.9.1048a ◽

2000 ◽

Vol 84 (9) ◽

pp. 1048-1048 ◽

Cited By ~ 1

Author(s):

G. S. Saenz ◽

S. T. Koike ◽

N. Shishkoff

Keyword(s):

United States ◽

New York ◽

North America ◽

Powdery Mildew ◽

Fungal Growth ◽

The United States ◽

Voucher Specimen ◽

First Report ◽

Humidity Chamber ◽

Powdery Mildew Pathogen

Gray-leaved Euryops (Euryops pectinatus Cass., Asteraceae) is an evergreen shrub that is widely planted in landscapes in the United States. In the fall of 1999, powdery mildew was observed on E. pectinatus planted in landscapes in Redlands (San Bernardino County), CA. Symptoms consisted only of slight cupping of leaves. Fungal growth was observed on stems, leaves, petioles, and pedicels and was ectophytic and amphigenous. The white mycelium was patchy to effuse. Hyphal appressoria were indistinct (1). Conidiophore foot cells were cylindric and sometimes were tapered toward or constricted at the base. Foot cells measured 30 to 50 by 10 to 12 μm and were followed by one to two shorter cells. Conidia were cylindric to slightly doliform, borne in chains of two to three, and measured 26 to 38 by 14 to 18 μm. Conidial length to width ratios ranged from 1.7 to 2.4. Catenate conidia had crenate edge lines (3). Conidia possessed conspicuous fibrosin bodies and from their sides produced short germ tubes without appressoria. Cleistothecia were not observed. Based on these characters, the fungus was identified as Podosphaera fusca (Fr.) U. Braun & N. Shishkoff (Podosphaera sect. Sphaerotheca) (1,2). Pathogenicity was confirmed by gently pressing diseased leaves onto leaves of healthy E. pectinatus plants. Plants were incubated in a humidity chamber at 22 to 24°C and after 12 to 14 days powdery mildew colonies developed. E. pectinatus cv. Viridis, a cultivar that lacks the extensive pubescence of E. pectinatus, also developed disease when inoculated. This appears to be the first report of powdery mildew on E. pectinatus in North America. A voucher specimen has been deposited into the University of California Herbarium (accession # UC1738635). P. fusca was also observed on cv. Viridis in a nursery in New York in 1999. It is unclear where this pathogen originated. P. fusca parasitizes a large number of asteraceous species including dandelion (Taraxacum officinalis) and sowthistle (Sonchus spp.) weeds, which occur in the area and sometimes are infected with powdery mildew. The Euryops powdery mildew pathogen may be a race that is different than those found on other composites in the United States. The fungus was observed on plants in shaded areas but not on plants in full sun. References: (1) U. Braun. Nova Hedwigia 89:1, 1987. (2) U. Braun and S. Takamatsu. Schlechtendalia 4:1, 2000. (3) H. D. Shin and Y. J. La. Mycotaxon 46:445, 1993.

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First Report of Powdery Mildew Caused by an Oidium sp. on Banana Shrub (Michelia figo)

Plant Disease ◽

10.1094/pdis.1999.83.2.198c ◽

1999 ◽

Vol 83 (2) ◽

pp. 198-198 ◽

Cited By ~ 1

Author(s):

G. E. Holcomb

Keyword(s):

United States ◽

Powdery Mildew ◽

Baton Rouge ◽

The United States ◽

Sexual Stage ◽

First Report ◽

Leaf Chlorosis ◽

Leaf Surfaces ◽

Powdery Mildew Fungi ◽

Severity Of The Disease

Banana shrub (Michelia figo (Lour.) Spreng.) is an evergreen grown in southern landscapes in hardiness zones 7 to 9. A powdery mildew disease has been observed sporadically on this plant for several years in the Baton Rouge area during fall months, but symptoms were always mild. During the summer and fall of 1998, banana shrub plants were observed with moderately severe powdery mildew infections that resulted in leaf chlorosis, distortion, and some defoliation. An Oidium sp. was present on both leaf surfaces, but sporulation was more abundant on the abaxial surfaces. Conidia were ellipsoid, produced in chains, devoid of conspicuous fibrosin bodies, and averaged 37 × 19 μm. No sexual stage was found. Conidia brushed from infected leaves to healthy leaves of a potted banana shrub maintained in a greenhouse caused new infections in 5 to 8 days. Factors responsible for the increased severity of the disease in 1998 are unknown, but the unusually dry summer may have contributed to the increased incidence of this disease. An Oidium sp. was listed on M. figo in Australia and the United States (1), but no other reports were found to confirm this. This is the first report of the occurrence of a powdery mildew on M. figo in the United States. Reference: (1) K. Amano. Host Range and Geographical Distribution of the Powdery Mildew Fungi. Japan Scientific Press, Tokyo, 1986.

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Mosquito and Tick-borne Illnesses in the United States. Guidelines for the Recognition and Empiric Treatment of Zoonotic Diseases in the Wilderness.

Infectious Disorders - Drug Targets ◽

10.2174/1871526518666180626123340 ◽

2019 ◽

Vol 19 (3) ◽

pp. 238-257

Author(s):

Suresh Antony

Keyword(s):

United States ◽

Lyme Disease ◽

Spotted Fever ◽

Disease Process ◽

Rocky Mountain ◽

The United States ◽

Health Care Facilities ◽

Diagnostic Tools ◽

Rocky Mountain Spotted Fever ◽

Number Of Patients

Background:In the United States, tick-borne illnesses account for a significant number of patients that have been seen and treated by health care facilities. This in turn, has resulted in a significant morbidity and mortality and economic costs to the country.Methods:The distribution of these illnesses is geographically variable and is related to the climate as well. Many of these illnesses can be diagnosed and treated successfully, if recognized and started on appropriate antimicrobial therapy early in the disease process. Patient with illnesses such as Lyme disease, Wet Nile illness can result in chronic debilitating diseases if not recognized early and treated.Conclusion:This paper covers illnesses such as Lyme disease, West Nile illness, Rocky Mountain Spotted fever, Ehrlichia, Tularemia, typhus, mosquito borne illnesses such as enteroviruses, arboviruses as well as arthropod and rodent borne virus infections as well. It covers the epidemiology, clinical features and diagnostic tools needed to make the diagnosis and treat these patients as well.

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338. Analysis of Etiologies of Aseptic Meningitis within a Nation-Wide Hospital Network

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.533 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S239-S239

Author(s):

Arunmozhi S Aravagiri ◽

Scott Kubomoto ◽

Ayutyanont Napatkamon ◽

Sarah Wilson ◽

Sudhakar Mallela

Keyword(s):

United States ◽

West Nile Virus ◽

Aseptic Meningitis ◽

Epidemiologic Study ◽

The United States ◽

Positive Test ◽

Diagnostic Tools ◽

West Nile ◽

Varicella Zoster ◽

The Us

Abstract Background Aseptic meningitis can be caused by an array of microorganisms, both bacterial and non-bacterial, as well as non-infectious conditions. Some etiologies of aseptic meningitis require treatment with antibiotics, antiviral, antifungals, anti-parasitic agents, immunosuppressants, and or chemotherapy. There are limited diagnostic tools for diagnosing certain types of aseptic meningitis, therefore knowing the differential causes of aseptic meningitis, and their relative percentages may assist in diagnosis. Review of the literature reveals that there are no recent studies of etiologies of aseptic meningitis in the United States (US). This is an epidemiologic study to delineate etiologies of aseptic meningitis in a large database of 185 HCA hospitals across the US. Methods Data was collected from January 2016 to December 2019 on all patients diagnosed with meningitis. CSF PCR studies, and CSF antibody tests were then selected for inclusion. Results Total number of encounters were 3,149 hospitalizations. Total number of individual labs analyzed was 10,613, and of these 262 etiologies were identified. 23.6% (62) of cases were due to enterovirus, 18.7% (49) due to HSV-2, 14.5% (38) due to West Nile virus, 13.7% (36) due to Varicella zoster (VZV), 10.5% (27) due to Cryptococcus. Additionally, we analyzed the rate of positive test results by region. Nationally, 9.7% of tests ordered for enterovirus were positive. In contrast, 0.5% of tests ordered for HSV 1 were positive. The southeastern United States had the highest rate of positive tests for HSV 2 (7% of tests ordered for HSV 2 were positive). The central United States had the highest rate of positive test for West Nile virus (11% of tests ordered for West Nile were positive). The northeastern region and the highest rate of positive tests for varicella zoster (18%). Table 1: Percentage of positive CSF tests (positive tests/tests ordered) Table 2: Lists the number of HIV patients and transplant patients that had positive CSF PCR/serologies Figure 1: Percentage of positive CSF tests in each region Conclusion Approximately 40% of aseptic meningitis population had treatable etiologies. A third of the Cryptococcus meningitis population had HIV. Furthermore, enteroviruses had the majority of cases within the US, which are similar to studies done in other parts of the world. Disclosures All Authors: No reported disclosures

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Corrected Genome Sequence of Acinetobacter baumannii Strain AB0057, an Antibiotic-Resistant Isolate from Lineage 1 of Global Clone 1

Genome Announcements ◽

10.1128/genomea.00836-17 ◽

2017 ◽

Vol 5 (35) ◽

Cited By ~ 7

Author(s):

Mohammad Hamidian ◽

Pratap Venepally ◽

Ruth M. Hall ◽

Mark D. Adams

Keyword(s):

United States ◽

Acinetobacter Baumannii ◽

Genome Sequence ◽

The United States ◽

Targeted Sequencing ◽

Resistant Isolate ◽

Illumina Hiseq ◽

Antibiotic Resistant ◽

Content Type ◽

Pcr Products

ABSTRACT Extensively antibiotic-resistant Acinetobacter baumannii isolate AB0057 recovered in the United States in 2004 was one of the first global clone 1 isolates to be completely sequenced. Here, the complete 4.05-Mb genome sequence (chromosome and one plasmid) has been revised using Illumina HiSeq data and targeted sequencing of PCR products.

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First Report of Powdery Mildew Caused by Erysiphe aquilegiae var. aquilegiae on Aquilegia flabellata in Italy

Plant Disease ◽

10.1094/pdis.2004.88.6.681a ◽

2004 ◽

Vol 88 (6) ◽

pp. 681-681

Author(s):

A. Garibaldi ◽

D. Bertetti ◽

M. L. Gullino

Keyword(s):

United States ◽

Powdery Mildew ◽

The United States ◽

Northern Italy ◽

American Phytopathological Society ◽

First Report ◽

Powdery Mildews ◽

The Family ◽

White Mycelium ◽

The University

Aquilegia flabellata Sieb. and Zucc. (columbine) is a perennial garden species belonging to the family Ranunculaceae. During the summer of 2003, a severe outbreak of a previously unknown powdery mildew was observed in several gardens near Biella (northern Italy). Upper surfaces of leaves were covered with a white mycelium and conidia, and as the disease progressed infected leaves turned yellow and died. Foot cell was cylindric and appressorium lobed. Conidia were hyaline, ellipsoid, and measured 31.2 to 47.5 × 14.4 to 33 μm (average 38.6 × 21.6 μm). Fibrosin bodies were not present. Cleistothecia were globose, brown, had simple appendages, ranged from 82 to 127 (average 105) μm in diameter, and contained one to two asci. Ascocarp appendages measured five to eight times the ascocarp diameter. Asci were cylindrical (ovoidal) and measured 45.3 to 58.2 × 30.4 to 40.2 μm. Ascospores (three to four per ascus) were ellipsoid or cylindrical and measured 28.3 to 31.0 × 14.0 to 15.0 μ;m. On the basis of its morphology, the pathogen was identified as Erysiphe aquilegiae var. aquilegiae (1). Pathogenicity was confirmed by gently pressing diseased leaves onto leaves of five, healthy A. flabellata plants. Five noninoculated plants served as controls. Inoculated and noninoculated plants were maintained in a garden where temperatures ranged between 20 and 30°C. After 10 days, typical powdery mildew symptoms developed on inoculated plants. Noninoculated plants did not show symptoms. To our knowledge, this is the first report of the presence of powdery mildew on Aquilegia flabellata in Italy. E. communis (Wallr.) Link and E. polygoni DC. were reported on several species of Aquilegia in the United States (2), while E. aquilegiae var. aquilegiae was previously observed on A. flabellata in Japan and the former Union of Soviet Socialist Republics (3). Specimens of this disease are available at the DIVAPRA Collection at the University of Torino. References: (1) U. Braun. Nova Hedwigia, 89:700, 1987. (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) K. Hirata. Host Range and Geographical Distribution of the Powdery Mildews. Faculty of Agriculture, Niigata University, 1966.

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Alternanthera mosaic virus Found in Scutellaria, Crossandra, and Portulaca spp. in Florida

Plant Disease ◽

10.1094/pd-90-0833c ◽

2006 ◽

Vol 90 (6) ◽

pp. 833-833 ◽

Cited By ~ 11

Author(s):

C. A. Baker ◽

L. Breman ◽

L. Jones

Keyword(s):

Electron Microscopy ◽

United States ◽

Mosaic Virus ◽

Plant Species ◽

The United States ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

Indicator Plants ◽

Partial Identity ◽

Pcr Products

In the fall of 1998, the Division of Plant Industry (DPI) received vegetative propagations of Scutellaria longifolia (skullcap) with symptoms of foliar mosaic, chlorotic/necrotic ringspots, and wavy line patterns from a nursery in Manatee County. Flexuous particles approximately 500 nm long were found with electron microscopy. The plants tested positive for Papaya mosaic virus (PaMV) in an enzyme-linked immunosorbent assay (ELISA) test with antiserum to PaMV (Agdia, Elkhart, IN). However, in immunodiffusion tests (antiserum from D. Purcifull, University of Florida), this virus gave a reaction of partial identity indicating it was related but not identical to PaMV (1). The original infected plants were kept in a greenhouse. In January 2005, a specimen of Crossandra infundibuliformis (firecracker plant) with mosaic symptoms was submitted to the DPI from a nursery in Alachua County. Inclusions found with light microscopy and particles found with electron microscopy indicated that this plant was infected with a potexvirus. This was confirmed by reverse transcription-polymerase chain reaction (RT-PCR) with primers designed to detect members of the virus family Potexviridae (3). These plants reacted positive to PaMV antiserum in ELISA and gave a reaction of partial identity to PaMV in immunodiffusion. A specimen of Portulaca grandiflora (moss rose) with distorted leaves found at a local retail store was also tested and gave the same results. Leaves from each of the three plant species were rubbed onto a set of indicator plants using Carborundum and potassium phosphate buffer. Total RNA was extracted from symptomatic indicator plants of Nicotiana benthamiana. RT-PCR (3) was performed, and PCR products were sequenced directly. Sequences of approximately 700 bp were obtained for all three plant species and showed 98% identity with each other. BLAST search results showed that these sequences were 93% identical to an Alternanthera mosaic virus (AltMV) sequence at the nucleotide level but only 76% identical to PaMV. The amino acid sequences were 98 and 82% identical to AltMV and PaMV, respectively. The PCR products of the virus from Scutellaria sp. were cloned, resequenced, and the sequence was entered into the GenBank (Accession No. DQ393785). The bioassay results matched those found for AltMV in Australia (2) and the northeastern United States (4), except that the Florida viruses infected Datura stramonium and Digitalis purpurea (foxglove). The virus associated with the symptoms of these three plants appears to be AltMV and not PaMV. AltMV has been found in ornamental plants in Australia, Italy, and the United States (Pennsylvania, Maryland, and now Florida). Since this virus is known to infect several plants asymptomatically and can be easily confused with PaMV serologically, it is likely that the distribution of this virus is much wider than is known at this time. References: (1) L. L. Breman. Plant Pathology Circular No. 396. Fla. Dept. Agric. Consum. Serv. DPI, 1999. (2) A. D. W. Geering and J. E. Thomas. Arch Virol 144:577, 1999. (3) A. Gibbs et al. J Virol Methods 74:67, 1998. (4) J. Hammond et al. Arch Virol. 151:477, 2006.

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First Report of Peanut mottle virus in Forage Peanut (Arachis pintoi) in the United States

Plant Health Progress ◽

10.1094/php-12-17-0076-br ◽

2018 ◽

Vol 19 (1) ◽

pp. 13-14

Author(s):

K. K. Dey ◽

L. Hassell ◽

C. Li ◽

M. Elliott ◽

X. Sun

Keyword(s):

United States ◽

The United States ◽

Mottle Virus ◽

Arachis Glabrata ◽

First Report ◽

Arachis Pintoi ◽

Reverse Transcription Pcr ◽

The World ◽

Pcr Products ◽

The Many

Arachis pintoi is one of the many perennial peanuts grown in many tropical and subtropical countries around the world. Although Peanut mottle virus (PeMoV) was reported in Arachis glabrata from Georgia in 2007, there are no reports of PeMoV infecting A. pintoi in the United States. In June 2017, samples of A. pintoi that originated from Hardee County, FL, plants showed a variety of symptoms ranging from yellowing to dark islands, green vein banding, and mild mottling. They tested positive initially with broad-spectrum lateral flow antibody immunoassay and later were confirmed by sequencing the reverse-transcription PCR products. Detection of PeMoV in A. pintoi is significant because it is transmitted by aphids in a nonpersistent manner and is seed-borne in A. hypogea. It is not known if PeMoV is seed-borne in A. pintoi. However, A. pintoi is commonly vegetatively propagated using stolon cuttings. It is possible that PeMoV can spread to A. pintoi in Florida by all these means, making maintenance of virus-free propagation stock plants important. To our knowledge, this is the first report of PeMoV in A. pintoi the United States.

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Steam Generator Asset Management Program

18th International Conference on Nuclear Engineering: Volume 1 ◽

10.1115/icone18-29471 ◽

2010 ◽

Author(s):

Padmanabha J. Prabhu ◽

Damian A. Testa

Keyword(s):

United States ◽

Steam Generator ◽

Asset Management ◽

Strategic Plan ◽

The United States ◽

Management Program ◽

Diagnostic Tools ◽

Steam Generators ◽

Pressurized Water

The Steam Generator Asset Management Program (SGAMP) is a long term program designed to maximize the performance and reliability of the steam generators. The SGAMP focuses on plant specific conditions and hence is applicable to the original or the replacement steam generators. It is recommended that the utility and the vendor form a joint steam generator management team (SGMT) to develop, monitor and implement a long-term plan to address steam generator operation, maintenance and life extension goals. The SGMT will consist of representatives from operations, chemistry, maintenance and engineering functions and will be responsible for making decisions related to the steam generators. The charter of the SGMT is to develop a steam generator strategic plan that will cost-effectively manage steam generator options. The strategic plan is consistent with the Steam Generator Program Guidelines (NEI 97-06 in the United States). The strategic plan is a living document and is revised periodically to incorporate inspection results, new technology developments, lessons learned and industry experience. Cost-benefit analyses of strategies may be performed to prolong steam generator operability through steam generator performance modeling (tube degradation, fouling, etc.), diagnostic tools, regulatory strategy, condition monitoring and operational assessment strategy, and maintenance strategy. The SGMT will provide input regarding potential maintenance of the steam generators with schedule and cost impacts for each outage. It will also recommend engineering evaluations to be performed in support of program goals and will develop short- and long-term recommendations. These recommendations will address action plans, performance measures and results. Secondary side inspection and cleaning strategy should be developed (techniques and frequency) to maximize performance cost-effectively. This paper is based on Westinghouse experience gained by working with several pressurized water reactor (PWR) plant operators in the United States (US).

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Development of a diagnostic assay for race differentiation of Podosphaera macularis

Plant Disease ◽

10.1094/pdis-06-20-1289-re ◽

2020 ◽

Author(s):

Mary Block ◽

Brian Knaus ◽

Michele S. Wiseman ◽

Niklaus J. Grünwald ◽

David H. Gent

Keyword(s):

Powdery Mildew ◽

Pacific Northwest ◽

The United States ◽

Epidemiological Studies ◽

Locked Nucleic Acid ◽

Nucleotide Polymorphisms ◽

Practical Applications ◽

Powdery Mildew Fungi ◽

Perfect Discrimination ◽

Podosphaera Macularis

Hop powdery mildew (caused by Podosphaera macularis) was confirmed in the Pacific Northwest in 1996. Before 2012, the most common race of P. macularis was able to infect plants that possessed powdery mildew resistance based on the R-genes Rb, R3, and R5. After 2012, two additional races of P. macularis were discovered that can overcome the resistance gene R6 and the partial resistance found in the cultivar Cascade. These three races now occur throughout the region, which can complicate management and research efforts because of uncertainty on which race(s) may be present in the region and able to infect susceptible hop genotypes. Current methods for determining the races of P. macularis are labor intensive, costly, and typically require more than 14 days to obtain results. We sought to develop a molecular assay to differentiate races of the fungus possessing virulence on plants with R6, referred to as V6-virulent, from other races. The transcriptomes of 46 isolates of P. macularis were sequenced to identify loci and variants unique to V6-isolates. Fourteen primer pairs were designed for 10 candidate loci that contained single nucleotide polymorphisms (SNP) and short insertion-deletion polymorphisms. Two differentially-labeled locked nucleic acid probes were designed for a contig that contained a conserved SNP associated with V6-virulence. The resulting duplexed real-time PCR assay was validated against 46 V6 and 54 non-V6 P. macularis isolates collected from the United States and Europe. The assay had perfect discrimination of V6-virulence among isolates of P. macularis originating from the western U.S. but failed to predict V6-virulence in three isolates collected from Europe. The specificity of the assay was tested with different species of powdery mildew fungi and other microorganisms associated with hop. Weak non-specific amplification occurred with powdery mildew fungi collected from Vitis vinifera, Fragaria sp., and Zinnia sp.; however, non-specification amplification is not a concern when differentiating pathogen race from colonies on hop. The assay has practical applications in hop breeding, epidemiological studies, and other settings where rapid confirmation of pathogen race is needed.

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