scholarly journals Ralstonia solanacearum Race 3, Biovar 2 Strains Isolated from Geranium Are Pathogenic on Potato

Plant Disease ◽  
2002 ◽  
Vol 86 (9) ◽  
pp. 987-991 ◽  
Author(s):  
Lynn Williamson ◽  
Kazuhiro Nakaho ◽  
Brian Hudelson ◽  
Caitilyn Allen
Keyword(s):  
United States ◽  
Ralstonia Solanacearum ◽  
Ornamental Plants ◽  
Brown Rot ◽  
The United States ◽  
Enzyme Linked Immunosorbent Assay ◽  
Economic Damage ◽  
Biochemical Tests ◽  
Potato Brown Rot ◽  
Rot Disease

Ralstonia solanacearum race 3, biovar 2 is a soilborne bacterium that causes potato brown rot disease in temperate and subtropical climates. Recent outbreaks of this disease in Europe have caused serious losses, but the pathogen had not been identified in the United States. However, in 1999, strains of R. solanacearum were isolated from wilting geraniums growing in Wisconsin greenhouses. Physiological and biochemical tests of the Wisconsin strains and a similar strain from South Dakota demonstrated that the strains belong to R. solanacearum subgroup biovar 2, which is largely synonymous with the race 3 subgroup, a classification based on host range. These results were confirmed by polymerase chain reaction analyses in which race 3, biovar 2-specific primers amplified a fragment of the expected size. This is the first report of race 3, biovar 2 in the United States, and it is the first known occurrence of race 3, biovar 2 in Wiscon-sin. The geranium strains were highly pathogenic on both geranium and potato. The presence of R. solanacearum race 3, biovar 2 in the United States raises concern that the bacterium could move from ornamental plants into potato fields, where it could cause both direct economic damage and quarantine problems. A commercial indirect enzyme-linked immunosorbent assay for R. solanacearum produced some false negatives for these strains, indicating that current indexing may not be sufficient to identify this destructive pathogen.

scholarly journals Genome Resource: Ralstonia solanacearum Phylotype II Sequevar 1 (Race 3 Biovar 2) Strain UW848 From the 2020 U.S. Geranium Introduction

Plant Disease ◽  
2021 ◽  
Vol 105 (1) ◽  
pp. 207-208
Author(s):  
Veronica Roman-Reyna ◽  
Alicia Truchon ◽  
Parul Sharma ◽  
Francesca Peduto Hand ◽  
Reza Mazloom ◽  
...  
Keyword(s):  
United States ◽  
Ralstonia Solanacearum ◽  
Draft Genome ◽  
Brown Rot ◽  
The United States ◽  
Tropical Lowland ◽  
Global Pandemic ◽  
Pandemic Strains ◽  
Potato Brown Rot ◽  
Tomato Bacterial Wilt

Ralstonia solanacearum phylotype II sequevar 1 (RsII-1, formerly race 3 biovar 2) causes tomato bacterial wilt, potato brown rot, and Southern wilt of geranium. Strains in RsII-1 cause wilting in potato and tomato at cooler temperatures than tropical lowland R. solanacearum strains. Although periodically introduced, RsII-1 has not established in the United States. This pathogen is of quarantine concern and listed as a Federal Select Agent. We report a rapidly sequenced (<2 days) draft genome of UW848, a RsII-1 isolate introduced to the United States in geranium cuttings in spring 2020. UW848 belongs to the near-clonal cluster of RsII-1 global pandemic strains.

Protective Role of Copper Oxide-Streptomycin Nano-drug Against Potato Brown Rot Disease Caused by Ralstonia solanacearum

2021 ◽  
Author(s):  
Mohamed S. Attia ◽  
Naglaa M. Balabel ◽  
Ibtisam M. Ababutain ◽  
Mahmoud S. Osman ◽  
Mohamed M. Nofel ◽  
...  
Keyword(s):  
Copper Oxide ◽  
Ralstonia Solanacearum ◽  
Brown Rot ◽  
Protective Role ◽  
Potato Brown Rot ◽  
Rot Disease

scholarly journals Ralstonia solanacearum Race 3, Biovar 2, the Causal Agent of Brown Rot of Potato, Identified in Geraniums in Pennsylvania, Delaware, and Connecticut

Plant Disease ◽  
2003 ◽  
Vol 87 (4) ◽  
pp. 450-450 ◽  
Author(s):  
S. H. Kim ◽  
T. N. Olson ◽  
N. W. Schaad ◽  
G. W. Moorman
Keyword(s):  
United States ◽  
Polymerase Chain Reaction ◽  
Bacterial Wilt ◽  
Ralstonia Solanacearum ◽  
The United States ◽  
Enzyme Linked Immunosorbent Assay ◽  
Chain Reaction ◽  
Carbohydrate Utilization ◽  
Tetrazolium Chloride ◽  
Polymerase Chain

The Plant Disease Diagnostic Laboratory of the Pennsylvania Department of Agriculture received diseased geranium (Pelargonium × hortorum) samples from several Pennsylvania (PA) greenhouses in 1999 and 2000 and from one Delaware (DE) greenhouse in 1999. Originating from Guatemala, plants exhibited yellowing, wilting, stunting, and bacterial oozing from the vascular tissues. Isolations on yeast dextrose-CaCO3 (YDC) and triphenyl-tetrazolium-chloride (TTC) agars resulted in off-white mucoid colonies and white, fluidal colonies with pink centers, respectively. Such colonies are typical of Ralstonia solanacearum (1). The disease was similar to a bacterial wilt of geranium caused by an unidentified biovar of R. solanacearum (3). Preliminary tests using Biolog MicroLog 3 (Hayward, Ca; 4.01A) and enzyme-linked immunosorbent assay (ELISA) (Agdia Inc., Elkhart, IN; BRA 33900/0500) identified the organism as R. solanacearum. For pathogenicity tests, a 10-μl droplet of water suspension containing 1 × 106 CFU of each of five geranium strains (PDA 22056-99, 81849-99, 81862-99, 51032-00, and 64054-00) per milliliter was placed on a stem wound made by cutting off the terminal growth of each of 4 6-leaf stage plants of geranium ‘Orbit Scarlet’, tomato ‘Rutgers’, potato ‘Russet Norkotah’, and eggplant ‘Black Beauty’ in a growth chamber at 28°C, 86% relative humidity, and 12 h light/dark cycle. Water was included as a control. The five strains caused severe yellowing and wilting within 10 days. Colonies typical of R. solanacearum were reisolated from symptomatic tissue on YDC and TTC. To determine the specific biovar, 20 pathogenic geranium strains from PA and DE plus a strain of R. solanacearum originally isolated from a geranium plant of Guatemalan origin received from Connecticut in 1995 were grown up to 28 days on Ayers mineral medium supplemented with a 1% final concentration of D-cellobiose, dextrose, meso-inositol, lactose, maltose, D-ribose, trehalose, mannitol, sorbitol, or dulcitol (1). Acid was produced by 21 test strains from the first five carbohydrates only. Such carbohydrate utilization is typical of bv 2 (1). Bv 2 identification was confirmed by real-time polymerase chain reaction using bv 2-specific primers and probes (N. Schaad, unpublished) designed from a bv 2-specific DNA fragment (2). All tested strains were positive using ELISA. In contrast, strains of bv 2 from geraniums in Wisconsin and South Dakota were reported to be negative using ELISA (4). From our results, it appears that bv 2 was introduced into the United States on geraniums from Guatemala in 1995 and 1999. This cool climate bv 2, a regulated agent by the Agricultural Bioterrorism Protection Act of 2002, has caused extensive crop loss in potatoes in Europe, but has not been found in potatoes in the United States. References: (1) T. P. Denny and A. C. Hayward. Ralstonia solanacearum. Pages 151–174 in: Lab Guide for Identification of Plant Pathogenic Bacteria. N. W. Schaad et al. eds. 3rd ed. The American Phytopathological Society, St. Paul, MN, 2001. (2) M. Fagen et al. Development of a diagnostic test based on the polymerase chain reaction (PCR) to identify strains of R. solanacearum exhibiting the Biovar 2 genotype. Pages 34–43 in: Bacterial Wilt Disease: Molecular and Ecological Aspects. P. H. Prior et al. eds. Springer-Verlag, Berlin, 1998. (3) D. L. Strider et al. Plant Dis. 65:52, 1981. (4) L. Williamson et al. (Abstr.) Phytopathology 91 (Suppl.):S95, 2001.

scholarly journals Genome-Enabled Phylogeographic Investigation of the Quarantine Pathogen Ralstonia solanacearum Race 3 Biovar 2 and Screening for Sources of Resistance Against Its Core Effectors

2015 ◽  
Vol 105 (5) ◽  
pp. 597-607 ◽  
Author(s):  
Christopher R. Clarke ◽  
David J. Studholme ◽  
Byron Hayes ◽  
Brendan Runde ◽  
Alexandra Weisberg ◽  
...  
Keyword(s):  
Resistance Genes ◽  
Ralstonia Solanacearum ◽  
Genetic Resistance ◽  
Brown Rot ◽  
The United States ◽  
South American ◽  
Sources Of Resistance ◽  
Quarantine Pathogen ◽  
Potato Brown Rot ◽  
Core Effectors

Phylogeographic studies inform about routes of pathogen dissemination and are instrumental for improving import/export controls. Genomes of 17 isolates of the bacterial wilt and potato brown rot pathogen Ralstonia solanacearum race 3 biovar 2 (R3bv2), a Select Agent in the United States, were thus analyzed to get insight into the phylogeography of this pathogen. Thirteen of fourteen isolates from Europe, Africa, and Asia were found to belong to a single clonal lineage while isolates from South America were genetically diverse and tended to carry ancestral alleles at the analyzed genomic loci consistent with a South American origin of R3bv2. The R3bv2 isolates share a core repertoire of 31 type III-secreted effector genes representing excellent candidates to be targeted with resistance genes in breeding programs to develop durable disease resistance. Toward this goal, 27 R3bv2 effectors were tested in eggplant, tomato, pepper, tobacco, and lettuce for induction of a hypersensitive-like response indicative of recognition by cognate resistance receptors. Fifteen effectors, eight of them core effectors, triggered a response in one or more plant species. These genotypes may harbor resistance genes that could be identified and mapped, cloned, and expressed in tomato or potato, for which sources of genetic resistance to R3bv2 are extremely limited.

scholarly journals Estimating economic damage from climate change in the United States

Science ◽  
2017 ◽  
Vol 356 (6345) ◽  
pp. 1362-1369 ◽  
Author(s):  
Solomon Hsiang ◽  
Robert Kopp ◽  
Amir Jina ◽  
James Rising ◽  
Michael Delgado ◽  
...  
Keyword(s):  
Climate Change ◽  
United States ◽  
Climate Science ◽  
The United States ◽  
Process Models ◽  
Economic Damage ◽  
Global Mean Temperature ◽  
Flexible Architecture ◽  
Econometric Analyses ◽  
Business As Usual

Estimates of climate change damage are central to the design of climate policies. Here, we develop a flexible architecture for computing damages that integrates climate science, econometric analyses, and process models. We use this approach to construct spatially explicit, probabilistic, and empirically derived estimates of economic damage in the United States from climate change. The combined value of market and nonmarket damage across analyzed sectors—agriculture, crime, coastal storms, energy, human mortality, and labor—increases quadratically in global mean temperature, costing roughly 1.2% of gross domestic product per +1°C on average. Importantly, risk is distributed unequally across locations, generating a large transfer of value northward and westward that increases economic inequality. By the late 21st century, the poorest third of counties are projected to experience damages between 2 and 20% of county income (90% chance) under business-as-usual emissions (Representative Concentration Pathway 8.5).

scholarly journals Meningococcal Antigen Typing System (MATS)-Based Neisseria meningitidis Serogroup B Coverage Prediction for the MenB-4C Vaccine in the United States

mSphere ◽  
2017 ◽  
Vol 2 (6) ◽  
Author(s):  
Gowrisankar Rajam ◽  
Maria Stella ◽  
Ellie Kim ◽  
Simon Paulos ◽  
Giuseppe Boccadifuoco ◽  
...  
Keyword(s):  
United States ◽  
Vaccine Coverage ◽  
Binding Protein ◽  
The United States ◽  
Factor H ◽  
Enzyme Linked Immunosorbent Assay ◽  
Immune Reactivity ◽  
Content Type ◽  
Efficacy Trials ◽  
Typing System

ABSTRACT The meningococcal antigen typing system (MATS) is an enzyme-linked immunosorbent assay (ELISA)-based system that assesses the levels of expression and immune reactivity of the three recombinant MenB-4C antigens and, in conjunction with PorA variable 2 (VR2) sequencing, provides an estimate of the susceptibility of NmB isolates to killing by MenB-4C-induced antibodies. MATS assays or similar antigen phenotype analyses assume importance under conditions in which analyses of vaccine coverage predictions are not feasible with existing strategies, including large efficacy trials or functional antibody screening of an exhaustive strain panel. MATS screening of a panel of NmB U.S. isolates (n = 442) predicts high MenB-4C vaccine coverage in the United States. Neisseria meningitidis is the most common cause of bacterial meningitis in children and young adults worldwide. A 4-component vaccine against N. meningitidis serogroup B (MenB) disease (MenB-4C [Bexsero]; GSK) combining factor H binding protein (fHBP), neisserial heparin binding protein (NHBA), neisserial adhesin A (NadA), and PorA-containing outer membrane vesicles was recently approved for use in the United States and other countries worldwide. Because the public health impact of MenB-4C in the United States is unclear, we used the meningococcal antigen typing system (MATS) to assess the strain coverage in a panel of strains representative of serogroup B (NmB) disease in the United States. MATS data correlate with killing in the human complement serum bactericidal assay (hSBA) and predict the susceptibility of NmB strains to killing in the hSBA, the accepted correlate of protection for MenB-4C vaccine. A panel of 442 NmB United States clinical isolates (collected in 2000 to 2008) whose data were down weighted with respect to the Oregon outbreak was selected from the Active Bacterial Core Surveillance (ABCs; CDC, Atlanta, GA) laboratory. MATS results examined to determine strain coverage were linked to multilocus sequence typing and antigen sequence data. MATS predicted that 91% (95% confidence interval [CI95], 72% to 96%) of the NmB strains causing disease in the United States would be covered by the MenB-4C vaccine, with the estimated coverage ranging from 88% to 97% by year with no detectable temporal trend. More than half of the covered strains could be targeted by two or more antigens. NHBA conferred coverage to 83% (CI95, 45% to 93%) of the strains, followed by factor H-binding protein (fHbp), which conferred coverage to 53% (CI95, 46% to 57%); PorA, which conferred coverage to 5.9%; and NadA, which conferred coverage to 2.5% (CI95, 1.1% to 5.2%). Two major clonal complexes (CC32 and CC41/44) had 99% strain coverage. The most frequent MATS phenotypes (39%) were fHbp and NHBA double positives. MATS predicts over 90% MenB-4C strain coverage in the United States, and the prediction is stable in time and consistent among bacterial genotypes. IMPORTANCE The meningococcal antigen typing system (MATS) is an enzyme-linked immunosorbent assay (ELISA)-based system that assesses the levels of expression and immune reactivity of the three recombinant MenB-4C antigens and, in conjunction with PorA variable 2 (VR2) sequencing, provides an estimate of the susceptibility of NmB isolates to killing by MenB-4C-induced antibodies. MATS assays or similar antigen phenotype analyses assume importance under conditions in which analyses of vaccine coverage predictions are not feasible with existing strategies, including large efficacy trials or functional antibody screening of an exhaustive strain panel. MATS screening of a panel of NmB U.S. isolates (n = 442) predicts high MenB-4C vaccine coverage in the United States.

scholarly journals First Report of Sclerotinia sclerotiorum on Campanula carpatica and Schizanthus × wisetonensis in Italy

Plant Disease ◽  
2002 ◽  
Vol 86 (1) ◽  
pp. 71-71
Author(s):  
A. Garibaldi ◽  
A. Minuto ◽  
M. L. Gullino
Keyword(s):  
United States ◽  
Sclerotinia Sclerotiorum ◽  
Ornamental Plants ◽  
Soil Surface ◽  
The United States ◽  
First Report ◽  
Potted Plants ◽  
Initial Symptoms ◽  
Stem Necrosis ◽  
Campanula Carpatica

The production of potted ornamental plants is very important in the Albenga Region of northern Italy, where plants are grown for export to central and northern Europe. During fall 2000 and spring 2001, sudden wilt of tussock bellflower (Campanula carpatica Jacq.) and butterfly flower (Schizanthus × wisetonensis Hort.) was observed on potted plants in a commercial greenhouse. Initial symptoms included stem necrosis at the soil line and yellowing and tan discoloration of the lower leaves. As stem necrosis progressed, infected plants growing in a peat, bark compost, and clay mixture (70-20-10) wilted and died. Necrotic tissues were covered with whitish mycelia that produced dark, spherical (2 to 6 mm diameter) sclerotia. Sclerotinia sclerotiorum was consistently recovered from symptomatic stem pieces of both plants disinfested for 1 min in 1% NaOCl and plated on potato dextrose agar amended with streptomycin sulphate at 100 ppm. Pathogenicity of three isolates obtained from each crop was confirmed by inoculating 45- to 60-day-old C. carpatica and Schizanthus × wisetonensis plants grown in containers (14 cm diameter). Inoculum that consisted of wheat kernels infested with mycelia and sclerotia of each isolate was placed on the soil surface around the base of previously artificially wounded or nonwounded plants. Noninoculated plants served as controls. All plants were maintained outdoors where temperatures ranged between 8 and 15°C. Inoculated plants developed symptoms of leaf yellowing, followed by wilt, within 7 to 10 days, while control plants remained symptomless. White mycelia and sclerotia developed on infected tissues and S. sclerotiorum was reisolated from inoculated plants. To our knowledge, this is the first report of stem blight of C. carpatica and Schizanthus × wisetonensis caused by S. sclerotiorum in Italy. The disease was previously observed on C. carpatica in Great Britain (2) and on Schizanthus sp. in the United States (1). References: (1) D. F. Farr et al. Fungi on Plants and Plant Products in the United States. The American Phytopathological Society, St. Paul, MN, 1989. (2) J. Rees. Welsh J. Agric. 1:188, 1925.

scholarly journals First Report of Lolium latent virus in Ryegrass in the United States

Plant Disease ◽  
2006 ◽  
Vol 90 (4) ◽  
pp. 528-528 ◽  
Author(s):  
C. J. Maroon-Lango ◽  
J. Hammond ◽  
S. Warnke ◽  
R. Li ◽  
R. Mock
Keyword(s):  
United States ◽  
Lolium Perenne ◽  
The United States ◽  
Latent Virus ◽  
Hybrid Population ◽  
Enzyme Linked Immunosorbent Assay ◽  
Rt Pcr ◽  
High Sequence Identity ◽  
Lolium Perenne L ◽  
Pcr Test

Initial reports of the presence of Lolium latent virus (LLV) in Lolium perenne L. and L. multiflorum Lam. breeding clones in Germany, the Netherlands, France (2), and recently the United Kingdom (3,4; described as Ryegrass latent virus prior to identification as LLV) prompted us to evaluate clonally propagated Lolium plants from the United States. Four genetically distinct plants (viz., MF22, MF48, MF125, and MF132) that have been maintained clonally for 5 years from a Lolium perenne × L. multiflorum hybrid population established in the United States exhibited either no symptoms or mild chlorotic flecking that coalesced to form chlorotic to necrotic streaking on the leaves. All four clonal plants tested positive using reverse transcription-polymerase chain reaction (RT-PCR) with the Potexvirus group PCR test (Agdia, Inc., Elkhart, IN), whereas all clones but MF48 tested positive using the Potyvirus group PCR test (Agdia, Inc.). No amplicons were obtained when the same plants were tested for tobamovirus, carlavirus, and closterovirus using appropriate virus group-specific primers. Cloning and sequencing of the potexviral amplicons revealed very high sequence identity with the comparable region of LLV-UK (GenBank Accession No. DQ333886), whereas those of the potyviral amplicons (GenBank Accession Nos. DQ355837 and DQ355838) were nearly identical with the comparable region of Ryegrass mosaic virus (RGMV), a rymovirus first reported from the United States in 1957 (1). Using indirect enzyme-linked immunosorbent assay (ELISA), extracts from all four Lolium clonal propagations tested positive for LLV using the antiserum raised to LLV-Germany (courtesy of Dr. Huth), whereas the potyvirus-positive results from RT-PCR of the three clones were confirmed using indirect ELISA with the broad spectrum potyvirus monoclonal antibody, PTY-1. LLV from singly or dually infected Lolium clones was transmitted to Nicotiana benthamiana Domin. but not to N. tabacum L. by mechanical inoculation. LLV was purified from infected N. benthamiana. Similar sized flexuous rods were observed using electron microscopy in leaf dip samples from Lolium clones and aliquots of the virions purified from N. benthamiana. References: (1) G. W. Bruehl et al. Phytopathology 47:517, 1957. (2) W. Huth et al. Agronomie 15:508, 1995. (3) R. Li et al. Asian Conf. Plant Pathol. 2:89, 2005. (4) C. Maroon-Lango et al. Int. Congr. Virol. 13:63, 2005.

scholarly journals Cucumber Mosaic Virus, Tobacco Streak Virus, and Cucumber Mosaic Virus Satellite RNA Associated with Mosaic and Ringspot Symptoms in Ajuga reptans in Ohio

Plant Disease ◽  
1997 ◽  
Vol 81 (10) ◽  
pp. 1214-1214 ◽  
Author(s):  
J. R. Fisher ◽  
S. T. Nameth
Keyword(s):  
United States ◽  
Molecular Weight ◽  
Cucumber Mosaic Virus ◽  
Mosaic Virus ◽  
The United States ◽  
Negative Control ◽  
Enzyme Linked Immunosorbent Assay ◽  
Low Molecular Weight ◽  
Streak Virus ◽  
Ajuga Reptans

Creeping bugleweed (Ajuga reptans L.) is a perennial ornamental commonly grown as a ground cover in temperate climates. Commercial samples of the A. reptans cultivars Royalty, var. Atropurpurea Bronze, Bronze Beauty, and Burgundy Glow showing mosaic and ringspot symptoms were tested for the presence of virus infection by direct antibody sandwich enzyme-linked immunosorbent assay (ELISA) and viral-associated double-stranded (ds) RNA analysis. Cucumber mosaic cucumovirus (CMV) was detected by ELISA and dsRNA analysis in symptomatic samples of all cultivars tested. ELISA values were considered positive if the absorbance values were twice the negative control. Negative control values were established with asymptomatic tissue of the cv. Bronze Beauty. Tobacco streak ilarvirus (TSV) was detected only by ELISA in symptomatic samples of all cultivars except Royalty. No dsRNA suggestive of TSV was detected. Alfalfa mosaic virus (AMV) was detected by ELISA and dsRNA analysis in symptomatic samples of all cultivars tested except Royalty and var. Atropurpurea Bronze. dsRNA analysis also indicated the presence of a low molecular weight, possible satellite (sat) RNA associated with all symptomatic and asymptomatic Royalty and var. Atropurpurea Bronze plants tested. Northern (RNA) blot analysis with a digoxigenin-labeled full-length clone of the (S) CARNA-5 (-) CMV satRNA (ATCC no. 45124) confirmed that the low molecular weight RNA associated with the Royalty and var. Atropurpurea Bronze cultivars was indeed CMV satRNA. Only AMV has been previously reported in A. reptans in the United States (1). This is the first report of CMV and its satRNA, as well as TSV, in A. reptans in the United States. Reference: (1) W. T. Schroeder and R. Provvidenti. Plant Dis. Rep. 56:285, 1972.

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

Plant Disease ◽  
2006 ◽  
Vol 90 (6) ◽  
pp. 833-833 ◽  
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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