Iris Yellow Spot Tospovirus Detected in Onion (Allium cepa) in Israel

During March 1997, 20 to 30% of field-grown onion (Allium cepa), observed in Bet Shean Valley, Israel, had unusual viral symptoms of straw-colored ringspots on leaves and flower stalks. Leaf samples were analyzed by transmission electron microscopy (EM) of leaf dip preparations. Typical tospovirus-like particles were observed only with samples taken from symptomatic plants. Crude sap from symptomatic tissue was mechanically transmitted to Nicotiana benthamiana, Chenopodium quinoa, and Gomphrena globosa. On inoculated plants of N. benthamiana, chlorotic spots developed on inoculated leaves, followed by systemic necrosis, 4 and 7 days post inoculation (DPI), respectively. On inoculated plants of C. quinoa and G. globosa, necrotic local lesions developed by 4 to 5 DPI. EM studies with ultrathin sections of infected onion and N. benthamiana leaves revealed the presence of tospovirus-like particles. Virus was purified from mechanically infected N. benthamiana and identified as Iris yellow spot tospovirus (IYSV) by Western blots (immunoblots) and enzyme-linked immunosorbent assay (ELISA) (anti-IYSV antiserum was provided by D. Peters, Wageningen, the Netherlands). A high incidence of the disease observed in the surrounding fields and in other onion-growing areas in Israel was associated with large populations of the onion thrips (Thrips tabaci). Although characteristic symptoms have been noted on a frequent basis, effects on yield have yet to be determined. IYSV is known to occur in the Netherlands, where it has been occasionally detected in Iris (1) and leek (A. Porrum) (J. Verhoeven, personal communication). The detection of IYSV in Israel and the wide distribution of thrips in the natural vegetation may be an important constraint on onion and other bulb-crop production in Israel. Reference: (1) A. F. L. M. Derks and M. E. C. Lemmers. Acta Hortic. 432:132, 1996.

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First Report of Tomato Spotted Wilt Virus on Potatoes in Iran

Plant Disease ◽

10.1094/pdis.2001.85.4.442b ◽

2001 ◽

Vol 85 (4) ◽

pp. 442-442 ◽

Cited By ~ 14

Author(s):

R. Pourrahim ◽

Sh. Farzadfar ◽

A. A. Moini ◽

N. Shahraeen ◽

A. Ahoonmanesh

Keyword(s):

Tomato Spotted Wilt Virus ◽

Chenopodium Quinoa ◽

Plant Viruses ◽

Thrips Tabaci ◽

Enzyme Linked Immunosorbent Assay ◽

Leaf Extracts ◽

Systemic Necrosis ◽

First Report ◽

Tomato Spotted Wilt ◽

Wilt Virus

Severe leaf and stem necrosis before flowering was observed in potato (Solanum tuberosum) fields of Firouzkoh Province, Iran, during the summer of 1998. Infected plants died before the end of the growing season. Necrosis was more severe in cv. Agria than in cvs. Ajaxs and Arinda. A high population of Thrips tabaci was observed in August and September. Tomato spotted wilt virus (TSWV) (1) was detected in affected potatoes by using specific TSWV-IgG (from Bioreba) in double-antibody sandwich enzyme linked immunosorbent assay and by indicator plant reactions. Mechanical inoculation of indicator plants with leaf extracts of symptomatic potatoes produce necrotic local lesions in Chenopodium quinoa, C. amaranticolor, Gomphrena globosa, Vicia faba, Vigna sinensis, Phaseolus aureus var. Gohar, P. vulgaris, and Petunia hybrida. The virus caused systemic necrosis in Capsicum frutescens, Datura stramonium, D. metel, Nicotiana glutinosa, N. rustica, and Trapaeolum majus, preceded by systemic chlorotic spots. TSWV was reported from ornamental crops in Tehran and Absard areas near to Firouzkoh province (2), but this is the first report of TSWV occurrence on potatoes in Iran. References: (1) T. S. Ie. Descriptions of Plant Viruses. No. 39, 1970. (2) A. A. Moeini, et al. Iran. J. Plant Pathol. (In press.)

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First Report of a Tospovirus Infection of Peanuts in Iran

Plant Disease ◽

10.1094/pdis.2001.85.12.1286c ◽

2001 ◽

Vol 85 (12) ◽

pp. 1286-1286 ◽

Cited By ~ 6

Author(s):

A. R. Golnaraghi ◽

N. Shahraeen ◽

R. Pourrahim ◽

Sh. Ghorbani ◽

Sh. Farzadfar

Keyword(s):

Chenopodium Quinoa ◽

Datura Stramonium ◽

Enzyme Linked Immunosorbent Assay ◽

Leaf Extracts ◽

Systemic Necrosis ◽

First Report ◽

Severe Stunting ◽

Gomphrena Globosa ◽

Golestan Province ◽

Wilt Virus

During the summer of 2000, severe stunting, mosaic, bud necrosis, and chlorosis symptoms were observed on peanut (Arachis hypogaea cv. Gilan) plants growing in fields in the Golestan Province of Iran. Leaf extracts of peanut plants were infective (mechanical inoculation) causing necrotic local lesions on Chenopodium quinoa, C. amaranticolor, Gomphrena globosa, Phaseolus vulgaris cv. Talash, Vicia faba, and Vigna unguiculata cv. Mashad; systemic chlorotic spots were followed by systemic necrosis in Datura stramonium, D. metel, and Nicotiana rustica; chlorotic and necrotic spots were followed by top necrosis in Glycine max. About 2 weeks after inoculation, the chlorosis followed by stunting and bud necrosis observed in the field were reproduced in A. hypogaea cv. Gilan. Tomato spotted wilt virus (TSWV) was detected in the original peanut plants and in plant species that developed symptoms after inoculation with extracts from peanut plants, when analyzed by double-antibody sandwich enzyme-linked immunosorbent assay using TSWV-specific antisera (polyclonal antibody As-0526 and As-0580, DSMZ, Braunschweig, Germany). TSWV is one of the most important viruses in the world (2) and has been reported on potato (3) and tomato (1) in Iran. To our knowledge, this is the first report of TSWV infection of peanut in Iran. References: (1) K. Bananej et al. Iran. J. Plant Pathol. 34:30, 1998. (2) R. A. Mumford et al. Ann. Appl. Biol. 128:159, 1996. (3) R. Pourrahim et al. Plant Dis. 85:442, 2001.

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IRIS YELLOW SPOT VIRUS IN THE NETHERLANDS: OCCURRENCE IN ONION AND CONFIRMATION OF TRANSMISSION BY THRIPS TABACI

Acta Horticulturae ◽

10.17660/actahortic.2011.901.25 ◽

2011 ◽

pp. 199-206 ◽

Cited By ~ 2

Author(s):

K. Hoedjes ◽

J.T.J. Verhoeven ◽

R. Goldbach ◽

D. Peters

Keyword(s):

The Netherlands ◽

Thrips Tabaci ◽

Iris Yellow Spot Virus ◽

Yellow Spot ◽

Spot Virus

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Evaluation of Lisianthus as an Indicator Host for Iris yellow spot virus

Plant Disease ◽

10.1094/pdis-06-10-0473 ◽

2011 ◽

Vol 95 (12) ◽

pp. 1520-1527 ◽

Cited By ~ 3

Author(s):

Rajagopalbabu Srinivasan ◽

Stan Diffie ◽

Sivamani Sundaraj ◽

Stephen W. Mullis ◽

David Riley ◽

...

Keyword(s):

Transmission Rate ◽

Thrips Tabaci ◽

Iris Yellow Spot Virus ◽

Yellow Spot ◽

Effect Of Temperature ◽

Enzyme Linked Immunosorbent Assay ◽

Mechanical Transmission ◽

Symptom Expression ◽

Spot Virus ◽

Temperature Regimes

Iris yellow spot virus (IYSV) can severely affect onion production. IYSV is transmitted by the onion thrips, Thrips tabaci. However, information on IYSV–thrips–onion interactions is limited due to the difficulty associated with infecting onion plants experimentally. Lisianthus (Eustoma russellianum) was used as an indicator host to study mechanical transmission of IYSV, IYSV transmission by T. tabaci, IYSV distribution in the host plant, and the effect of temperature on IYSV symptom expression. Mechanical inoculation tests from IYSV-infected onion plants to noninfected lisianthus plants resulted in a mean transmission rate of 82.5 ± 6.9% (mean ± standard error), and from IYSV-infected lisianthus plants to noninfected lisianthus plants resulted in a mean transmission rate of 89.2 ± 7.1%. T. tabaci adults transmitted IYSV at a rate of 80.0 ± 8.3% from infected onion plants to noninfected lisianthus plants. To assess IYSV distribution in infected lisianthus plants, leaf sections, stems, and roots were tested by enzyme-linked immunosorbent assay (ELISA). All the plant parts tested positive for IYSV, but not on every plant assayed. Alternating night and day temperatures of 18 and 23°C, 25 and 30°C, and 30 and 37°C were evaluated for the effects on IYSV symptom expression. More severe symptoms developed on inoculated plants incubated at the 18 and 23°C or 25 and 30°C temperature regimes than at the 30 and 37°C regime, and symptoms were observed earliest on plants incubated at the 25 and 30°C temperature regime compared to the other temperature regimes.

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Potential factors contributing to the decline of Iris Yellow Spot Virus in organically grown onion crops in Canterbury and Hawke's Bay over three years

New Zealand Plant Protection ◽

10.30843/nzpp.2018.71.116 ◽

2018 ◽

Vol 71 ◽

pp. 39-44

Author(s):

Melanie M. Davidson ◽

Mette C. Nielson ◽

John D. Fletcher

Keyword(s):

New Zealand ◽

Allium Cepa ◽

Thrips Tabaci ◽

Iris Yellow Spot Virus ◽

Yellow Spot ◽

Spot Virus ◽

Potential Factors ◽

Organically Grown ◽

Organically Managed

The Tospovirus Iris yellow spot virus (IYSV), transmitted by thrips (predominantly Thrips tabaci), was first recorded in New Zealand in 2007. In March 2015, symptoms of the virus were relatively widespread in an organically managed onion crop in Canterbury. Onion plants were sampled for the presence of T. tabaci adults and larvae and for IYSV symptoms on an organically managed farm in Canterbury in 2014-2015, 2015-16 and 2016-17, and on a similar farm in Hawke's Bay in 2014-2015 and 2015-16. An immunoassay was used to confirm the presence of IYSV in some symptomatic plants. In Canterbury, IYSV symptoms were less apparent in 2015-16 and no symptoms were observed in 2016-17. No IYSV symptoms were observed in the Hawke's Bay onion crop, despite relatively high T. tabaci numbers. The virus symptoms declined from when they were first observed in March 2015 to undetectable levels in 2016-17 in Canterbury, which may be attributed to crop location, fewer thrips and the absence of a disease reservoir in volunteer Allium cepa plants or other hosts.

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First Report of Vidalia Onion (Allium cepa) Naturally Infected with Tomato spotted wilt virus and Iris yellow spot virus (Family Bunyaviridae, Genus Tospovirus) in Georgia

Plant Disease ◽

10.1094/pdis.2004.88.11.1285b ◽

2004 ◽

Vol 88 (11) ◽

pp. 1285-1285 ◽

Cited By ~ 19

Author(s):

S. W. Mullis ◽

D. B. Langston ◽

R. D. Gitaitis ◽

J. L. Sherwood ◽

A. C. Csinos ◽

...

Keyword(s):

Tomato Spotted Wilt Virus ◽

Thrips Tabaci ◽

Iris Yellow Spot Virus ◽

Yellow Spot ◽

Unknown Etiology ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

Spot Virus ◽

Tomato Spotted Wilt ◽

Wilt Virus

Vidalia onion is an important crop in Georgia's agriculture with worldwide recognition as a specialty vegetable. Vidalia onions are shortday, Granex-type sweet onions grown within a specific area of southeastern Georgia. Tomato spotted wilt virus (TSWV) has been endemic to Georgia crops for the past decade, but has gone undetected in Vidalia onions. Tobacco thrips (Frankliniella fusca) and Western flower thrips (Frankliniella occidentalis) are the primary vectors for TSWV in this region, and a number of plant species serve as reproductive reservoirs for the vector or virus. Iris yellow spot virus (IYSV), an emerging tospovirus that is potentially a devastating pathogen of onion, has been reported in many locations in the western United States (2,4). Thrips tabaci is the known vector for IYSV, but it is unknown if noncrop plants play a role in its epidemiology in Georgia. During October 2003, a small (n = 12) sampling of onions with chlorosis and dieback of unknown etiology from the Vidalia region was screened for a variety of viruses, and TSWV and IYSV infections were serologically detected. Since that time, leaf and bulb tissues from 4,424 onion samples were screened for TSWV and IYSV using double antibody sandwich-enzyme linked immunosorbent assay (DAS-ELISA) with commercial kits (Agdia Inc., Elkhart, IN). Samples were collected from 53 locations in the Vidalia region during the growing season between November 2003 and March 2004. Plants exhibiting stress, such as tip dieback, necrotic lesions, chlorosis or environmental damage were selected. Of these, 306 were positive for TSWV and 396 were positive for IYSV using positive threshold absorbance of three times the average plus two standard deviations of healthy negative onion controls. Positive serological findings of the onion tissues were verified by immunocapture-reverse transcription-polymerase chain reaction (IC-RT-PCR) for TSWV (3) and RT-PCR for IYSV (1). In both instances, a region of the viral nucleocapsid (N) gene was amplified. The PCR products were analyzed with gel electrophoresis with an ethidium bromide stain in 0.8% agarose. Eighty-six percent (n = 263) of the TSWV ELISA-positive samples exhibited the expected 774-bp product and 55 percent (n = 217) of the IYSV ELISA-positive samples exhibited the expected 962-bp product. The reduced success of the IYSV verification could be attributed to the age and deteriorated condition of the samples at the time of amplification. Thrips tabaci were obtained from onion seedbeds and cull piles within the early sampling (n = 84) and screened for TSWV by the use of an indirect-ELISA to the nonstructural (NSs) protein of TSWV. Of the thrips sampled, 25 were positive in ELISA. While the incidence of IYSV and TSWV in the Vidalia onion crop has been documented, more research is needed to illuminate their potential danger to Vidalia onions. References: (1) I. Cortês et al. Phytopathology 88:1276, 1998. (2) L. J. du Toit et al. Plant Dis. 88:222, 2004. (3) R. K. Jain et al. Plant Dis. 82:900, 1998. (4) J. W. Moyer et al. (Abstr.) Phytopathology 93(suppl.):S115, 2003.

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Lisianthus Leaf Necrosis: A New Disease of Lisianthus Caused by Iris yellow spot virus

Plant Disease ◽

10.1094/pdis.2000.84.11.1185 ◽

2000 ◽

Vol 84 (11) ◽

pp. 1185-1189 ◽

Cited By ~ 31

Author(s):

A. Kritzman ◽

H. Beckelman ◽

S. Alexandrov ◽

J. Cohen ◽

M. Lampel ◽

...

Keyword(s):

Polyclonal Antibodies ◽

Iris Yellow Spot Virus ◽

Yellow Spot ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

Spot Virus ◽

Systemic Necrosis ◽

Nucleocapsid Gene ◽

Pcr Product ◽

Wilt Virus

Unusual viral symptoms were seen on lisianthus (Eustoma russellianum) grown in the Besor area in Israel. Symptoms included necrotic spots and rings on leaves and systemic necrosis. Preliminary analyses suggested that the disease was caused by a tospovirus. Virus particles typical of a tospovirus were observed with electron microscopy in samples taken only from symptomatic leaves. Double-antibody sandwich enzyme-linked immunosorbent assay tests of leaf sap, extracted from lisianthus and mechanically inoculated indicator plants, gave a strong positive reaction to Iris yellow spot virus (IYSV). Polyclonal antibodies prepared against IYSV enabled specific detection of the virus in crude sap from infected plants. Western blot analysis showed that IYSV was serologically distinct from Tomato spotted wilt virus (TSWV). Primers specific to the nucleocapsid gene of IYSV were used in a reverse transcription-polymerase chain reaction assay (RT-PCR) to verify the presence of IYSV. RT-PCR gave an expected PCR product of approximately 850 bp. The sequence of the cloned nucleocapsid gene confirmed the identity of IYSV, thus confirming IYSV infection of lisianthus. This is the first report of IYSV infection in dicotyledons.

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First Report of Onion (Allium cepa) Naturally Infected with Iris yellow spot virus in Peru

Plant Disease ◽

10.1094/pd-90-0377a ◽

2006 ◽

Vol 90 (3) ◽

pp. 377-377 ◽

Cited By ~ 8

Author(s):

S. W. Mullis ◽

R. D. Gitaitis ◽

C. Nischwitz ◽

A. S. Csinos ◽

Z. C. Rafael Mallaupoma ◽

...

Keyword(s):

The United States ◽

Thrips Tabaci ◽

Iris Yellow Spot Virus ◽

Yellow Spot ◽

N Gene ◽

Enzyme Linked Immunosorbent Assay ◽

Spot Virus ◽

First Report ◽

The Impact ◽

Das Elisa

Onions have become an important export crop for Peru during the last few years. The onions produced for export are primarily short-day onions and include Grano- or Granex-type sweet onions. The first of two growing seasons for onion in Peru occurs from February/March until September/October and the second occurs from September/October to December/January. Iris yellow spot virus (IYSV [family Bunyaviridae, genus Tospovirus]), primarily transmitted by onion thrips (Thrips tabaci), has been reported in many countries during recent years, including the United States (1,2). In South America, the virus was reported in Brazil during 1999 (3) and most recently in Chile during 2005 (4). During 2003, an investigation of necrotic lesions and dieback in onions grown near the towns of Supe and Ica, Peru led to the discovery of IYSV in this region. Of 25 samples of symptomatic plants collected from five different fields near Supe, 19 tested strongly positive and an additional three tested weakly positive for IYSV using double antibody sandwich-enzyme linked immunosorbent assay (DAS-ELISA) (Agdia Inc., Elkhart, IN). None of the samples tested positive for Tomato spotted wilt virus (TSWV). A number of onions with necrosis and dieback symptoms were also observed during 2004 and 2005. During September 2005, 25 plants with symptoms suspected to be caused by IYSV or TSWV in the Supe and Casma valleys were collected and screened for both viruses using DAS-ELISA. All plants screened were positive for IYSV. There was no serological indication of TSWV infection in these samples. The positive samples were blotted onto FTA cards (Whatman Inc., U.K.) to bind the viral RNA for preservation and processed according to the manufacturer's protocols. The presence of IYSV was verified by reverse transcription-polymerase chain reaction (RTPCR) using (5′-TCAGAAATCGAGAAACTT-3′) and (5′-TAATTATATCTATCTTTCTTGG-3′) as forward and reverse primers (1), respectively. The primers amplify the nucleocapsid (N) gene of IYSV, and the RT-PCR products from this reaction were analyzed with gel electrophoresis with an ethidium bromide stain in 0.8% agarose to verify the presence of this amplicon in the samples. Subsequent to the September 2005 sampling, 72 additional samples from regions in northern and southern Peru were analyzed in the same manner. The amplicons obtained were cloned, sequenced, and compared with known IYSV isolates for further verification. Onions have become a significant export crop for Peru, and more research is needed to determine the impact of IYSV on the Peruvian onion export crop. To our knowledge, this is the first report of IYSV in onion in Peru. References: (1) L. du Toit et al. Plant Dis. 88:222, 2004. (2) S. W. Mullis et al. Plant Dis. 88:1285, 2004. (3) L. Pozzer et al. Plant Dis. 83:345, 1999. (4) M. Rosales et al. Plant Dis. 89:1245, 2005.

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Hospedantes alternos de Iris yellow spot virus y trips en cultivos de cebolla de Morelos y Michoacán, México

Revista Mexicana de Fitopatología Mexican Journal of Phytopathology ◽

10.18781/r.mex.fit.1701-1 ◽

2017 ◽

Vol 35 (2) ◽

Author(s):

Norma Ávila Alistac ◽

Sergio Ramírez Rojas ◽

Ángel Rebollar Alviter ◽

Remigio Anastacio Guzmán Plazola

Keyword(s):

Allium Cepa ◽

Ricinus Communis ◽

Thrips Tabaci ◽

Iris Yellow Spot Virus ◽

Yellow Spot ◽

Rt Pcr ◽

Spot Virus ◽

Das Elisa

El objetivo de la investigación fue identificar hospedantes alternos de Iris yellow spot virus (IYSV) y establecer el rango de hospedantes del putativo vector(es) en regiones productoras de cebolla (Allium cepa) de Morelos y Michoacán, México. En 10 localidades de ambos estados se muestrearon cultivos de cebolla y arvenses, en presencia y ausencia del cultivo. Las plantas de cebolla se analizaron por RT-PCR y las arvenses por DAS-ELISA. Las arvenses se identificaron a nivel especie, los trips colectados de las mismas se establecieron colonias para su identificación por PCR, con iniciadores específicos que amplifican un segmento del gen de citocromo oxidasa I (COI). Se analizaron e identificaron 295 arvenses agrupadas en 56 especies (23 familias), todas resultaron negativas para IYSV. Se detectaron trips en 75 arvenses agrupadas en 17 especies. Se analizaron 33 poblaciones de trips (22 de Morelos y 11 de Michoacán). La secuenciación indicó identidad con Thrips tabaci con una homología superior a 97 %. Las arvenses Ricinus communis y Acalypha ostryifolia registraron el mayor número de T. tabaci. En cebolla se confirmó la presencia de IYSV con RT-PCR en las 10 parcelas muestreadas. Este es el primer reporte de la presencia de IYSV en el estado de Michoacán.

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