Identification of two novel poleroviruses and the occurrence of Tobacco bushy top disease causal agents in natural plants

AbstractTobacco bushy top disease (TBTD) is a devastating tobacco disease in the southwestern region of China. TBTD in the Yunnan Province is often caused by co-infections of several plant viruses: tobacco bushy top virus (TBTV), tobacco vein distorting virus (TVDV), tobacco bushy top virus satellite RNA (TBTVsatRNA) and tobacco vein distorting virus-associated RNA (TVDVaRNA). Through this study, two new poleroviruses were identified in two TBTD symptomatic tobacco plants and these two novel viruses are tentatively named as tobacco polerovirus 1 (TPV1) and tobacco polerovirus 2 (TPV2), respectively. Analyses of 244 tobacco samples collected from tobacco fields in the Yunnan Province through RT-PCR showed that a total of 80 samples were infected with TPV1 and/or TPV2, and the infection rates of TPV1 and TPV2 were 8.61% and 29.51%, respectively. Thirty-three TPV1 and/or TPV2-infected tobacco samples were selected for further test for TBTV, TVDV, TBTVsatRNA and TVDVaRNA infections. The results showed that many TPV1 and/or TPV2-infected plants were also infected with two or more other assayed viruses. In this study, we also surveyed TBTV, TVDV, TBTVsatRNA and TVDVaRNA infections in a total of 1713 leaf samples collected from field plants belonging to 29 plant species in 13 plant families and from 11 provinces/autonomous regions in China. TVDV had the highest infection rates of 37.5%, while TVDVaRNA, TBTV and TBTVsatRNA were found to be at 23.0%, 12.4% and 8.1%, respectively. In addition, TVDV, TBTV, TBTVsatRNA and TVDVaRNA were firstly detected of co-infection on 10 plants such as broad bean, pea, oilseed rape, pumpkin, tomato, crofton weed etc., and 1 to 4 of the TBTD causal agents were present in the samples collected from Guizhou, Hainan, Henan, Liaoning, Inner mongolia and Tibet autonomous regions. The results indicated that TBTD causal agents are expanding its host range and posing a risk to other crop in the field.

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Household transmission and incidence of positive SARS-CoV-2 RT-PCR in symptomatic healthcare workers, clinical course and outcome: a French hospital experience

Occupational and Environmental Medicine ◽

10.1136/oemed-2020-106866 ◽

2020 ◽

pp. oemed-2020-106866

Author(s):

Evguenia Krastinova ◽

Valérie Garrait ◽

Marie-Thérèse Lecam ◽

André Coste ◽

Emmanuelle Varon ◽

...

Keyword(s):

Healthcare Workers ◽

Current Smoker ◽

Infection Rates ◽

Rt Pcr ◽

Living Situation ◽

Household Transmission ◽

Occupational Profile ◽

Household Members ◽

French Hospital ◽

At Home

ObjectivesAlthough healthcare workers (HCWs) have been particularly affected by SARS-CoV-2, detailed data remain scarce. In this study, we investigated infection rates, clinical characteristics, occupational exposure and household transmission among all symptomatic HCWs screened by SARS-CoV-2 RT-PCR between 17 March (French lockdown) and 20 April.MethodsSARS-CoV-2 RT-PCR was proposed to symptomatic (new cough or dyspnoea) HCWs at Creteil Hospital in one of the Parisian suburbs most severely affected by COVID-19. Data on occupational profile, living situation and household, together with self–isolation and mask use at home were collected, as well as the number of cases in the household.ResultsThe incidence rate of symptomatic SARS-CoV-2 was estimated to be 5% (110/2188). A total of 110 (35%) of the 314 HCWs tested positive and 9 (8%) were hospitalised. On multivariate analysis, factors independently associated with positive RT-PCR were occupational profile with direct patient facing (OR 3.1, 95% CI 1.1 to 8.8), p<0.03), and presence of anosmia (OR 5.7, 95% CI 3.1 to 10.6), p<0.0001). Being a current smoker was associated with negative RT-PCR (OR 0.3, 95% CI 0.1 to 0.7), p=0.005). Transmission from HCWs to household members was reported in 9 (14%) cases, and 2 deaths occurred. Overall, self-isolation was possible in 52% of cases, but only 31% of HCWs were able to wear a mask at home.ConclusionThis is the first study to report infection rates among HCWs during the peak of the SARS-CoV-2 epidemic in France and the lockdown period, highlighting the risk related to occupational profile and household transmission.

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Comparison of ELISA and RT-PCR assays for the detection of Tomato spotted wilt virus in peanut

Peanut Science ◽

10.3146/ps08-024.1 ◽

2009 ◽

Vol 36 (2) ◽

pp. 133-137 ◽

Cited By ~ 1

Author(s):

P. M. Dang ◽

D. L. Rowland ◽

W. H. Faircloth

Keyword(s):

Tomato Spotted Wilt Virus ◽

Enzyme Linked Immunosorbent Assay ◽

Infection Rates ◽

Rt Pcr ◽

Chi Square ◽

Tomato Spotted Wilt ◽

Significant Difference ◽

Pcr Assays ◽

Chi Square Analysis ◽

Wilt Virus

Abstract Diagnosis of Tomato spotted wilt virus (TSWV) in peanut can be accomplished by enzyme-linked immunosorbent assay (ELISA) or reverse transcription polymerase chain reaction (RT-PCR) but there has been no report of a direct comparison of the success of the two assays in evaluating infection rates of field-grown peanut. We collected peanut root samples from field-grown plants, 76 in 2006 and 48 in 2007, and tested these samples by both ELISA and RT-PCR assays for the presence of TSWV. Out of 124 samples, 50 (40.3%) and 57 (46.0%) were positive for TSWV by ELISA and RT-PCR respectively. In 13.7% of these samples, ELISA and RT-PCR differed in their results. However, Chi square analysis showed no significant difference between the results for these two assays. This result supports the conclusion that ELISA and RT-PCR are comparable for detecting TSWV infection rates in field-grown peanuts.

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Development of RT-PCR and Nested PCR for Detecting Four Quarantine Plant Viruses Belonging to Nepovirus

Research in Plant Disease ◽

10.5423/rpd.2013.19.3.220 ◽

2013 ◽

Vol 19 (3) ◽

pp. 220-225 ◽

Cited By ~ 16

Author(s):

Siwon Lee ◽

Eun-Ha Kang ◽

Yong-Gil Shin ◽

Su-Heon Lee

Keyword(s):

Nested Pcr ◽

Plant Viruses ◽

Rt Pcr

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Viral Satellite RNAs for the Prevention of Cucumber Mosaic Virus (CMV) Disease in Field-Grown Pepper and Melon Plants

Plant Disease ◽

10.1094/pdis.1998.82.12.1298 ◽

1998 ◽

Vol 82 (12) ◽

pp. 1298-1303 ◽

Cited By ~ 20

Author(s):

M. S. Montasser ◽

M. E. Tousignant ◽

J. M. Kaper

Keyword(s):

Cucumber Mosaic Virus ◽

Mosaic Virus ◽

Plant Viruses ◽

Yield Reduction ◽

Satellite Rna ◽

Time Intervals ◽

Mild Strain ◽

Challenge Inoculation ◽

Satellite Rnas ◽

Cmv Disease

A benign viral satellite RNA, in combination with a mild strain of cucumber mosaic virus (CMV-S), was used as a “vaccine” or “preinoculum” to demonstrate the feasibility of protecting pepper (Capsicum annuum cv. California Wonder) and melon (Cucurbita melo cv. Janus des Canaries) against two severe CMV strains, CMV-D and CMV-16, in the final 2 years of a 4-year pilot field and greenhouse experiment. In the field, healthy pepper and melon seedlings challenged with CMV-D and CMV-16 reduced yields by 33 to 60%; CMV-S caused only limited yield reduction in pepper and had no effect on the yield of melon. Different time intervals between preinoculation of pepper and melon seedlings with CMV-S and challenge inoculation with the severe CMV strains were tested. All plants challenged 3 weeks after vaccination showed nearly complete protection from subsequent infection by severe strains. The yield from preinoculated and challenged pepper plants was 80% that of untreated plants, while the yield from preinoculated and challenged melon plants was increased slightly over the untreated control plants. The use of this technology for biological control of plant viruses is discussed.

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Pola sebaran tingkat infeksi bersama serotipe virus dengue di wilayah kajian RT-PCR Balai Besar Teknik Kesehatan Lingkungan dan Pengendalian Penyakit Yogyakarta: analisis data 2013-2015

Berita Kedokteran Masyarakat ◽

10.22146/bkm.11778 ◽

2016 ◽

Vol 32 (11) ◽

pp. 401

Author(s):

Fitria Wakano ◽

Lutfan Lazuardi ◽

Eggi Arguni ◽

Hari Kusnanto

Keyword(s):

Environmental Health ◽

Joint Infection ◽

Google Earth ◽

P Value ◽

Infection Rates ◽

Rt Pcr ◽

Regional Study ◽

Descriptive Research ◽

Virus Serotype ◽

Spread Of Infection

Pattern of concurrent infection of dengue virus serotype in the regional study areas of Yogyakarta Center for Environmental Health and Diseases Control: an analysis of 2013-2015 dataPurposeThis study aimed to determine the pattern in the spread of infection rates with dengue viral serotypes.MethodsThe study was a descriptive research with spatial mapping methods. Data of 132 respondents were collected based on RT-PCR in 2013-2015. The complete address of the village-level patient from the dengue arbovirosis surveillance data of the Center for Environmental Health and Diseases Control Yogyakarta were used to determine the coordinate points with utilization of RBI and Google Earth maps in searching addresses for distribution of case coordinate points. ResultsThere were similarities with the most complex quadruple joint infection rates of DEN in Semarang and Yogjakarta, while Kebumen obtained double DEN level. Three patterns of infection with DEN-1 and DEN-3 have p-value < 0.05 in Semarang in 2014, Sragen in 2015 and Semarang 2013 and 2 patterns in Gunung Kidul 2014 and Kulon Progo 2015. The patterns of infection with DEN-1, DEN-2 and DEN-3 in 2015 were covering Sragen and Semarang in 2013.ConclusionThe most complex areas of infection were Semarang and Yogyakarta. The pattern of most likely cluster infection with DEN-1 and DEN-3 and DEN-1, DEN-2 and DEN-3 allegedly was a result of two infected patients, different serotypes of different mosquitoes or infection of more than one serotype of Ae. aegypti or Ae. albopictus as the main vector.

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First Report on the Natural Occurrence of Cherry virus A in Mirabelle Plum (Prunus domestica var. insititia)

Plant Disease ◽

10.1094/pd-89-0433a ◽

2005 ◽

Vol 89 (4) ◽

pp. 433-433 ◽

Cited By ~ 5

Author(s):

L. Svanella-Dumas ◽

A. Marais ◽

P. Gentit ◽

J. Lamorte ◽

T. Candresse

Keyword(s):

Natural Infection ◽

Plant Viruses ◽

Natural Occurrence ◽

Prunus Domestica ◽

Rt Pcr ◽

Pcr Assay ◽

First Report ◽

Specific Pcr ◽

Specific Pcr Assay ◽

Prunus Spp

Cherry virus A (CVA) is a member of the Capillovirus genus (2). It was discovered serendipitously during cloning of the little cherry agent (2) and has since been shown to be relatively widespread in sweet and sour cherry (Prunus cerasus and P. avium) (2,3). It is currently unclear whether CVA is associated with any specific symptoms in these hosts. Although it can be transmitted by grafting and thus propagated in peach, it has not been reported to naturally infect any host other than cherry. Using a degenerate reverse transcription-polymerase chain reaction (RT-PCR) technique targeting a conserved region of the RNA-dependent RNA polymerase (RdRp) and allowing the amplification of members of the Trichovirus, Capillovirus, and Foveavirus genera of filamentous plant viruses (1), a number of symptomatic Prunus spp. germplasm were evaluated. Among these, a cv. Mirabelle dorée accession (Prunus domestica var. insititia P332) of French origin exhibited severe symptoms of rosetting, severe leaf and fruit deformation, and yellow mosaic occasionally turning necrotic. RT-PCR conducted on symptomatic samples produced an amplification product of the expected size (362 bp) in several independent experiments. Sequencing of these products yielded a single sequence (GenBank Accession No. AY792509) with 88.1% nucleotide identity and 93.2% amino acid identity with the type strain of CVA (2). Presence of a CVA isolate was independently confirmed using a CVA-specific PCR assay directly on the original plum material or following experimental transmission by grafting on several new hosts including apricot (P. armeniaca cv. Priana) and plum (P. domestica cv. Prune d'Ente). To our knowledge, this is the first report of natural infection of CVA in plum. The symptoms observed in the infected plum are reminiscent of those caused by severe Prune dwarf virus (PDV) strains. Infection by PDV was confirmed using a PDV-specific PCR assay. The contribution, if any, of CVA to the symptoms observed remains to be evaluated. These findings suggest that the possible presence of CVA in noncherry Prunus spp. hosts should be taken into consideration by quarantine and certification programs. References: (1) X. Foissac et al. Acta Hortic. 550:3743, 2001. (2) W. Jelkmann. J. Gen. Virol. 76:2015, 1995. (3) M. J. Kirby et al. Plant Pathol. 50:6, 2001.

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A Survey of Five Plant Viruses in Weeds and Tobacco in Poland

Agronomy ◽

10.3390/agronomy11081667 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1667

Author(s):

Grażyna Korbecka-Glinka ◽

Marcin Przybyś ◽

Beata Feledyn-Szewczyk

Keyword(s):

Mosaic Virus ◽

Potato Virus Y ◽

Plant Viruses ◽

Current Status ◽

Viral Pathogens ◽

Climate Conditions ◽

Tomato Spotted Wilt ◽

Tobacco Production ◽

Infected Tobacco ◽

Das Elisa

Weeds may contribute to the spread of plant virus epidemics by acting as reservoirs of viruses or/and their vectors. The aim of this research was to study the prevalence of five viral pathogens in weeds in the fields of solanaceous crops in six provinces in Poland differing with soil and climate conditions. Most of the sampled sites were associated with tobacco production. The total number of 157 samples of tobacco and 600 samples of weeds were subjected to DAS-ELISA detection of tomato spotted wilt orthotospovirus (TSWV), cucumber mosaic virus (CMV), potato virus Y (PVY), tobacco mosaic virus (TMV) and tobacco ringspot virus (TRSV). Twenty nine percent of samples of weeds were infected with at least one virus. TSWV and TMV were the most frequently detected in 17.5% and 14.7% of samples, respectively. In most provinces where infected tobacco was found, the same virus was also detected in weeds. Results of this survey are discussed in the context of the current status of virus epidemics in tobacco fields in Poland.

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First Report of the Green Rosette Variant of Groundnut Rosette Disease in Kenya

Plant Disease ◽

10.1094/pdis.1999.83.8.782a ◽

1999 ◽

Vol 83 (8) ◽

pp. 782-782 ◽

Cited By ~ 2

Author(s):

A. W. Wangai ◽

S. S. Pappu ◽

H. R. Pappu ◽

N. Okoko ◽

C. M. Deom ◽

...

Keyword(s):

Sub Saharan Africa ◽

Satellite Rna ◽

Rt Pcr ◽

Crop Season ◽

Production Constraints ◽

Pcr Product ◽

Arachis Hypogaea L ◽

Disease Surveys ◽

Polymerase Chain ◽

Sub Saharan

Groundnut (Arachis hypogaea L.) is an important food crop in sub-Saharan Africa. One of the major production constraints is groundnut rosette disease, which is caused by a complex of two viruses, groundnut rosette assistor luteovirus (GRAV) and groundnut rosette umbravirus (GRV) together with the associated satellite RNA (satRNA) (1). Two main forms of the disease have been described: chlorotic and the green rosette. Variants of the satRNA have been shown to be largely responsible for the different forms of the disease (1). Chlorotic rosette has been the predominant form in all of sub-Saharan Africa while green rosette has been reported in the western and southern regions of Africa (2). During the 1997-1998 crop season, disease surveys conducted in Kenya showed the incidence of the rosette disease in farmers' fields to be 24 to 40% in a total of 23 fields surveyed in the western regions of the country (Homabay, Kendubay, Kisumu) and 30% in 8 fields sampled in the Rift Valley (Cheplamus, Marigat) regions. Representative peanut plants showing rosette symptoms were analyzed for the presence of GRV by reverse transcription polymerase chain reaction (RT-PCR). With primers specific to a portion of ORF4 of GRV RNA (3), RT-PCR gave a product of expected size (approximately 300 bp). The PCR product was cloned in pGEM-T vector and sequenced. The sequenced region showed 89% nucleotide sequence identity with published GRV sequences. Green rosette was observed on groundnut cultivars Nyaela Red and Homabay Local in the Kendu Bay region. The incidence of the green rosette was 5.3% of the plants with rosette symptoms. References: (1) A. F. Murant and I. K. Kumar. Ann. Appl. Biol. 117:85, 1990. (2) R. A. Naidu et al. Ann. Appl. Biol. 132:525, 1998. (3). M. E. Taliansky et al. J. Gen. Virol. 77:2335, 1996.

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Virus Assessment of Ajuga reptans Cultivars Reveals Alfalfa Mosaic, Tobacco Streak, and Cucumber Mosaic (CMV) Viruses, and a CMV Satellite RNA

HortScience ◽

10.21273/hortsci.35.2.230 ◽

2000 ◽

Vol 35 (2) ◽

pp. 230-234 ◽

Cited By ~ 2

Author(s):

J.R. Fisher ◽

S.T. Nameth

Keyword(s):

Cdna Probe ◽

Alfalfa Mosaic Virus ◽

Northern Hybridization ◽

Enzyme Linked Immunosorbent Assay ◽

Mixed Infections ◽

Satellite Rna ◽

Rt Pcr ◽

Ajuga Reptans ◽

Tomato Spotted Wilt ◽

Cucumber Mosaic Cucumovirus

Ajuga reptans L. is an herbaceous ornamental mint grown in borders or as a groundcover, and is commonly propagated vegetatively and by seed. Three hundred and fifty-six A. reptans samples were obtained from growers in Washington, Michigan, Iowa, and Ohio, and screened for alfalfa mosaic virus (AMV), tobacco streak ilarvirus (TSV), cucumber mosaic cucumovirus (CMV), tomato aspermy cucumovirus (TAV), tomato spotted wilt tospovirus (TSWV), impatiens necrotic spot tospovirus (INSV), tobacco mosaic tobamovirus (TMV), potato virus × potexvirus (PVX), and 80 potyviruses, using direct antibody sandwich (DAS) and indirect enzyme-linked immunosorbent assay (ELISA). Viral-associated double-stranded ribonucleic acid (dsRNA) analysis was used to detect an apparent satellite (sat) RNA, and northern hybridization using a digoxigenin (DIG) labeled (S) CARNA-5 cDNA probe was used to confirm the identity of the apparent satRNA. No incidences of TAV, TMV, TSWV, INSV, PVX, or potyviruses were detected. CMV was detected in 11%, AMV in 22.2%, TSV in 3.7%, and mixed infections of CMV and AMV in 1.1% of the samples. SatRNA was detected in 36 A. reptans `Royalty', two `Rainbow', and two `Burgundy Glow' samples by dsRNA analysis, and confirmed by hybridization in 29 `Royalty' and one `Burgundy Glow' samples. Sixteen A. reptans `Royalty' seedlings grown from seed harvested from CMV-infected plants were tested by ELISA for CMV, AMV, and TSV. All were positive for CMV, and two were positive for a mixed infection of CMV and AMV. SatRNA was detected in all 16 seedlings by RT-PCR.

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First Report of Lettuce big-vein associated virus (Varicosavirus) Infecting Lettuce in Mexico

Plant Disease ◽

10.1094/pdis-07-13-0761-pdn ◽

2014 ◽

Vol 98 (4) ◽

pp. 573-573 ◽

Cited By ~ 3

Author(s):

D. L. Ochoa-Martínez ◽

J. Alfonsina-Hernández ◽

J. Sánchez-Escudero ◽

D. Rodríguez-Martínez ◽

J. Vera-Graziano

Keyword(s):

Mosaic Virus ◽

Consensus Sequence ◽

Leaf Tissue ◽

Plant Viruses ◽

Australian Isolate ◽

Healthy Plant ◽

Rt Pcr ◽

First Report ◽

Chlorotic Spot ◽

Spanish Isolate

Lettuce (Lactuca sativa) is a common consumed vegetable and a major source of income and nutrition for small farmers in Mexico. This crop is infected with at least nine viruses: Mirafiori lettuce big-vein virus (MiLBVV), Lettuce big-vein associated virus (LBVaV), both transmitted by the soil-borne fungus Olpidium brassicae; Tomato spotted wilt virus (TSWV), Tomato chlorotic spot virus (TCSV), Groundnut ringspot virus (GRSV), Lettuce mottle virus (LMoV), Cucumber mosaic virus (CMV), Bidens mosaic virus (BiMV), and Lettuce mosaic virus (LMV) (1). From March to May 2012, a disease on lettuce was observed in the south region of Mexico City displaying mild to severe mosaic, leaf deformation, reduced growth, slight thickening of the main vein, and plant death. At the beginning of the epidemic there were just a few plants with visible symptoms and 7 days later the entire crop was affected, causing a loss of 93% of the plants. It was estimated by counting the number of severely affected or dead plants in three plots. No thrips, aphids, or whiteflies were observed in the crop during this time. Twenty plants with similar symptoms were collected and tested by RT-PCR using the primers LBVaVF 5′-AACACTATGGGCATCCACAT-3′ and LBVaVR 5′-GCATGTCAGCAATCAGAGGA-3′ specific for the coat protein gene of LBVaV, amplifying a 322-bp fragment. Primers CP829F 5′-CCWACTTCATCAGTTGAGCGCTG-3′ and CP1418R 5′-TATCAGCTCCCTACACTATCCTCGC-3′ were used to detect MiLBVV (2). No amplification was obtained for MiLBVaV in any plants tested. PCR products of approximately 300 bp were obtained from four out of 20 symptomatic lettuce samples tested for LBVaV, but not from healthy plant and water controls. These results suggest the presence of another virus in symptomatic lettuce plants. Amplicons were gel-purified and sequenced using LBVaVF and LBVaVR primers. A consensus sequence was generated using the Bioedit v. 5 program. Both sequences of these Mexican lettuce isolates were 100% identical (Accession Nos. KC776266.1 and KC776267.1) and had identities between 94 and 99% to all sequences of LBVaV available in GenBank. Additionally, when alignments were made using ClustalW, these sequences showed identities of 99.7% to Almeria-Spanish isolate (Accession No. AY581686.1); 99.4% to Granada-Spanish isolate (AY581689.1); 99.1% to Dutch isolate (JN710441.1), Iranian isolate (JN400921.1), Australian isolate (GU220725.1), Brazilian isolate (DQ530354.1), England isolate (AY581690.1), and American isolate (AY496053.1); 96.2% to Australian isolate (GU220722.1); 96.3% to Japanese isolate (AB190527.1); and 92.8% to Murcia-Spanish isolate (AY581691.1). Twenty lettuce plants were mechanically inoculated with leaf tissue taken from the four plants collected in the field and tested positive for LBVaV by RT-PCR; 12 days after inoculation, mosaic symptoms were observed in all inoculated plants and six of them were analyzed individually by RT-PCR obtaining a fragment of the expected size. To our knowledge, this is the first report of LBVaV infecting lettuce in Mexico. Further surveys and monitoring of LBVaV incidence and distribution in the region, vector competence of olpidium species, and impact on the crop quality are in progress. References: (1) P. M. Agenor et al. Plant Viruses 2:35, 2008. (2) R. J. Hayes et al. Plant Dis. 90:233, 2006.

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