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Papaya ringspot virus

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Datasheet

Papaya ringspot virus

Summary

  • Last modified
  • 14 July 2018
  • Datasheet Type(s)
  • Invasive Species
  • Pest
  • Preferred Scientific Name
  • Papaya ringspot virus
  • Taxonomic Tree
  • Domain: Virus
  •   Unknown: "Positive sense ssRNA viruses"
  •     Unknown: "RNA viruses"
  •       Family: Potyviridae
  •         Genus: Potyvirus

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Pictures

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PictureTitleCaptionCopyright
Mosaic on papaya leaves in the field.
TitleSymptoms on leaves
CaptionMosaic on papaya leaves in the field.
CopyrightA.S. Costa
Mosaic on papaya leaves in the field.
Symptoms on leavesMosaic on papaya leaves in the field.A.S. Costa
Dark-green blisters and mosaic on papaya leaf.
TitleSymptoms on leaf
CaptionDark-green blisters and mosaic on papaya leaf.
CopyrightJ. Vega
Dark-green blisters and mosaic on papaya leaf.
Symptoms on leafDark-green blisters and mosaic on papaya leaf. J. Vega
Comparison of plant with leaf shoestring (left) with healthy plant (right). The leaf laminae of infected plants are markedly reduced in size, and may develop a shoestring appearance.
TitleSymptoms on leaves
CaptionComparison of plant with leaf shoestring (left) with healthy plant (right). The leaf laminae of infected plants are markedly reduced in size, and may develop a shoestring appearance.
CopyrightJorge A.M. Rezende
Comparison of plant with leaf shoestring (left) with healthy plant (right). The leaf laminae of infected plants are markedly reduced in size, and may develop a shoestring appearance.
Symptoms on leavesComparison of plant with leaf shoestring (left) with healthy plant (right). The leaf laminae of infected plants are markedly reduced in size, and may develop a shoestring appearance.Jorge A.M. Rezende
Comparison of leaf deformation caused by PRSV- P (left) with that caused by broad mite (Polyphagotharsonemus latus) (right).
TitleLeaf deformation
CaptionComparison of leaf deformation caused by PRSV- P (left) with that caused by broad mite (Polyphagotharsonemus latus) (right).
CopyrightJorge A.M. Rezende
Comparison of leaf deformation caused by PRSV- P (left) with that caused by broad mite (Polyphagotharsonemus latus) (right).
Leaf deformationComparison of leaf deformation caused by PRSV- P (left) with that caused by broad mite (Polyphagotharsonemus latus) (right).Jorge A.M. Rezende
Oily streaks on papaya stem; these streaks are frequently observed on the stem and leaf petioles of diseased plants.
TitleSymptoms on stem
CaptionOily streaks on papaya stem; these streaks are frequently observed on the stem and leaf petioles of diseased plants.
CopyrightA.S. Costa
Oily streaks on papaya stem; these streaks are frequently observed on the stem and leaf petioles of diseased plants.
Symptoms on stemOily streaks on papaya stem; these streaks are frequently observed on the stem and leaf petioles of diseased plants.A.S. Costa
Dark green, oily rings on papaya fruits; the number of rings on fruit can vary, and the rings become less distinct as the fruit mature and yellow.
TitleSymptoms on fruit
CaptionDark green, oily rings on papaya fruits; the number of rings on fruit can vary, and the rings become less distinct as the fruit mature and yellow.
CopyrightA.S. Costa
Dark green, oily rings on papaya fruits; the number of rings on fruit can vary, and the rings become less distinct as the fruit mature and yellow.
Symptoms on fruitDark green, oily rings on papaya fruits; the number of rings on fruit can vary, and the rings become less distinct as the fruit mature and yellow. A.S. Costa
Close-up of dark green, oily rings on papaya fruits.
TitleSymptoms on fruit
CaptionClose-up of dark green, oily rings on papaya fruits.
CopyrightA.S. Costa
Close-up of dark green, oily rings on papaya fruits.
Symptoms on fruitClose-up of dark green, oily rings on papaya fruits.A.S. Costa
Electron micrograph of PRSV- P particles.
TitleVirus particles
CaptionElectron micrograph of PRSV- P particles.
CopyrightJorge A.M. Rezende
Electron micrograph of PRSV- P particles.
Virus particlesElectron micrograph of PRSV- P particles.Jorge A.M. Rezende

Identity

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Preferred Scientific Name

  • Papaya ringspot virus

Other Scientific Names

  • papaw distortion ringspot virus
  • papaw mosaic virus
  • papaw ringspot virus
  • papaya distortion mosaic virus
  • papaya distortion ringspot virus
  • papaya leaf distortion virus
  • papaya ringspot potyvirus

International Common Names

  • English: cucurbits PRSV - strain W: watermelon; papaya PRSV - strain P: papaya

Local Common Names

  • Colombia: mancha anular de la papaya
  • Germany: Papaya Ringfleckenvirus; Wassermelonenvirus 1
  • Venezuela: deformación foliar y manchas en anillos; mosaico

English acronym

  • PRSV
  • PRSV-P
  • PRSV-W

EPPO code

  • PRSV00 (Papaya ringspot potyvirus)

Taxonomic Tree

Top of page
  • Domain: Virus
  •     Unknown: "Positive sense ssRNA viruses"
  •         Unknown: "RNA viruses"
  •             Family: Potyviridae
  •                 Genus: Potyvirus
  •                     Species: Papaya ringspot virus

Notes on Taxonomy and Nomenclature

Top of page Two strains of Papaya ringspot virus (PRSV) are recognized: PRSV-type P and PRSV-type W. PRSV-P and PRSV-W have been classified as strains of the same virus on the basis of morphological and serological similarities (Yeh et al., 1984). They also have a high percentage of nucleotide and amino acid sequence homologies on the NIb and coat protein genes (Quemada et al., 1990; Bateson and Dale, 1992; Wang and Yeh, 1992; Jain et al., 1998; Wang et al., 1998). They are distinguished only by host range. PRSV-P infects papaya and cucurbits, but causes a destructive disease only on papaya. PRSV-W infects cucurbits, but not papaya. Type W, which causes severe damage to cucurbits, was previously referred to as watermelon mosaic virus 1 (WMV-1) (Van Regenmortel, 1971). The International Committee on Taxonomy of Viruses still lists WMV-1 as a synonym for PRSV (Fauquet and Martelli, 1995). However, from recent results in Australia (J.L. Dale, personal communication, Queensland University of Technology, Australia, 1996), Brunt et al. (1996) treat PRSV and WMV-1 as separate viruses. The complete nucleotide sequence and genetic organization of the RNA genome of isolates of PRSV-P from Hawaii and Taiwan were determined by Yeh et al. (1992) and Wang and Yeh (1997), respectively. Based on the nucleotide sequence of the genomic RNAs, Wang and Yeh (1997) suggested that both PRSV-P strains were derived from different evolutionary pathways in different geographic areas.

Papaya ringspot disease was referred to as papaya mosaic in literature before the 1940s (Rezende, 1984). The latter name is presently associated with a disease caused by Papaya mosaic virus. The two viruses can be distinguished readily by particle morphology, the type of intracellular inclusion they induce in the host and by serological tests (Zettler et al., 1968; Purcifull et al., 1984). Also, Papaya mosaic virus does not have a known vector, being readily transmitted by mechanical inoculation.

Description

Top of page PRSV-P belongs to the the family Potyviridae, genus Potyvirus which typically have flexuous, filamentous particles, ca 760-800 nm long and 12 nm in diameter (Herold and Weibel, 1962; Purcifull et al., 1984; Murphy et al., 1995).

Distribution Table

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The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Continent/Country/RegionDistributionLast ReportedOriginFirst ReportedInvasiveReferenceNotes

Asia

BangladeshPresentAkanda et al., 1991; CABI/EPPO, 2003
ChinaPresentXiao et al., 1994; Xiao et al., 1997; CABI/EPPO, 2003
-FujianPresentKo et al., 1979; CABI/EPPO, 2003
-GuangdongPresentCABI/EPPO, 2003
-GuangxiPresentCABI/EPPO, 2003
-HainanPresentLu et al., 2008
-HenanPresentGu et al., 2008
-ShanxiPresentGu et al., 2008
IndiaPresentCapoor and Varma, 1948; CABI/EPPO, 2003
-Andhra PradeshPresentGourgopal and Jain, 2002
-BiharPresentCapoor and Varma, 1958; CABI/EPPO, 2003
-DelhiPresentCABI/EPPO, 2003
-Indian PunjabPresentCABI/EPPO, 2003
-KarnatakaPresentGude et al., 2008
-KeralaPresentRaj et al., 2007
-Madhya PradeshPresentRaj et al., 2007
-MaharashtraPresentLokhande and Moghe, 1991; CABI/EPPO, 2003; Verma et al., 2014
-RajasthanPresentSureka et al., 1977; CABI/EPPO, 2003
-Tamil NaduPresentJyoti et al., 2005
-Uttar PradeshPresentCapoor and Varma, 1958; CABI/EPPO, 2003
-West BengalPresentCapoor and Varma, 1958; CABI/EPPO, 2003
IndonesiaPresentSomowiyarjo, 1993; CABI/EPPO, 2003
-Irian JayaPresentDavis et al., 2002
IranPresentPourrahim et al., 2003
IsraelPresentCABI/EPPO, 2003
JapanPresentMaoka et al., 1995; CABI/EPPO, 2003
LebanonPresentKatul and Makkouk, 1987; CABI/EPPO, 2003
MalaysiaPresentWahab, 1991; CABI/EPPO, 2003
-Peninsular MalaysiaPresentCABI/EPPO, 2003
NepalPresentShrestha and Albrechtsen, 1992; CABI/EPPO, 2003
PakistanPresentAli et al., 2004; Noshad et al., 2015
PhilippinesPresentOpina, 1986; CABI/EPPO, 2003
SingaporePresentAVA, 2001; CABI/EPPO, 2003
Sri LankaRestricted distributionPerera et al., 1998; CABI/EPPO, 2003
SyriaPresentKatul and Makkouk, 1987; CABI/EPPO, 2003
TaiwanPresentWang et al., 1978; CABI/EPPO, 2003
ThailandPresentYeh and Gonsalves, 1994; CABI/EPPO, 2003
TurkeyPresentKöklü and Yilmaz, 2006
VietnamPresentCABI/EPPO, 2003
YemenPresentAlhubaishi et al., 1987; CABI/EPPO, 2003

Africa

Côte d'IvoirePresentDiallo et al., 2007
EgyptPresentOmar et al., 2011
MauritiusPresentGungoosingh-Bunwaree, 2001/2002
NigeriaPresentLana, 1980; CABI/EPPO, 2003
TanzaniaPresentCABI/EPPO, 2003
TunisiaPresentMnari-Hattab et al., 2008
UgandaPresentCABI/EPPO, 2003

North America

MexicoPresentBecerra, 1989; CABI/EPPO, 2003
USAWidespreadVidela, 1953; CABI/EPPO, 2003
-AlabamaPresentCABI/EPPO, 2003
-ArizonaPresentCABI/EPPO, 2003
-ArkansasPresentHander et al., 1993; CABI/EPPO, 2003
-CaliforniaPresentCABI/EPPO, 2003
-DelawarePresentCABI/EPPO, 2003
-FloridaPresentConover, 1964a; CABI/EPPO, 2003
-GeorgiaPresentCABI/EPPO, 2003
-HawaiiPresentParriss, 1938; Holmes et al., 1948; CABI/EPPO, 2003
-IllinoisPresentCABI/EPPO, 2003
-IndianaPresentCABI/EPPO, 2003
-KansasPresentCABI/EPPO, 2003
-LouisianaPresentFernandes et al., 1991; CABI/EPPO, 2003
-MainePresentCABI/EPPO, 2003
-MichiganPresentCABI/EPPO, 2003
-MissouriPresentCABI/EPPO, 2003
-New JerseyPresentCABI/EPPO, 2003
-New YorkPresentCABI/EPPO, 2003
-North CarolinaPresentCABI/EPPO, 2003
-OhioPresentCABI/EPPO, 2003
-OklahomaPresentCABI/EPPO, 2003
-PennsylvaniaPresentCABI/EPPO, 2003
-South CarolinaPresentCABI/EPPO, 2003
-TennesseePresentCABI/EPPO, 2003
-TexasPresentMiller, 1989; CABI/EPPO, 2003
-UtahPresentCABI/EPPO, 2003
-VermontPresentCABI/EPPO, 2003
-VirginiaPresentCABI/EPPO, 2003
-WashingtonPresentCABI/EPPO, 2003
-WisconsinPresentCABI/EPPO, 2003

Central America and Caribbean

BahamasPresentMcMillan et al., 1990; CABI/EPPO, 2003
British Virgin IslandsPresentCABI/EPPO, 2003
Costa RicaPresentRivera et al., 1993; CABI/EPPO, 2003
CubaPresentAcu±a & Zayas, 1940; CABI/EPPO, 2003; Mederos et al., 2015; Rodríguez-Martínez et al., 2015
Dominican RepublicPresentCiferri, 1930; Story and Halliwell, 1969
El SalvadorPresentRivas-Platero and Larios, 1994; CABI/EPPO, 2003
GuadeloupePresentCABI/EPPO, 2003
HondurasPresentEspinoza and McLeod, 1994; CABI/EPPO, 2003
JamaicaPresentAnon., 1995
Puerto RicoPresentADSUAR, 1947; CABI/EPPO, 2003
Saint Kitts and NevisPresentChin et al., 2008; Chin et al., 2008
Saint Kitts and NevisPresentChin et al., 2008; Chin et al., 2008
Trinidad and TobagoPresentBaker, 1938; CABI/EPPO, 2003
United States Virgin IslandsPresentCABI/EPPO, 2003

South America

BrazilPresentCABI/EPPO, 2003; Nakano et al., 2008
-BahiaWidespreadRezende and Costa, 1986; CABI/EPPO, 2003
-CearaWidespreadLima and Gomes, 1975; CABI/EPPO, 2003
-Espirito SantoWidespreadRezende and Costa, 1986; CABI/EPPO, 2003; Martins et al., 2016
-GoiasPresentKitajima et al., 1986; CABI/EPPO, 2003
-MaranhaoPresentCABI/EPPO, 2003
-ParanaPresentAlmeida and Carvalho, 1978; CABI/EPPO, 2003
-PernambucoWidespreadPaguio and Barbosa, 1979; CABI/EPPO, 2003
-Rio de JaneiroPresentKitajima et al., 1984; CABI/EPPO, 2003
-Rio Grande do NortePresentOliveira et al., 1992; CABI/EPPO, 2003
-Rio Grande do SulPresentVega and Robbs, 1988; CABI/EPPO, 2003
-RoraimaPresentHalfeld-Vieira et al., 2004
-Sao PauloPresentCosta et al., 1969; CABI/EPPO, 2003
ColombiaWidespreadTorres and Giacometti, 1966; CABI/EPPO, 2003
EcuadorPresentYeh et al., 1984; CABI/EPPO, 2003
VenezuelaPresentVidela, 1953; CABI/EPPO, 2003

Europe

CyprusPresentPapayiannis et al., 2005
FinlandPresent only under cover/indoorsEPPO, 2012EPPO Reporting Service, No. 2012/061. Under eradication.
FrancePresentVidela, 1953; CABI/EPPO, 2003
GermanyPresentVidela, 1953; CABI/EPPO, 2003
ItalyPresentVidela, 1953; CABI/EPPO, 2003
PolandPresentHasiów-Jaroszewska et al., 2010
SpainPresentCABI/EPPO, 2003

Oceania

AustraliaPresentThomas and Dodman, 1993; CABI/EPPO, 2003
-QueenslandPresentCABI/EPPO, 2003
Cook IslandsPresentDavis et al., 2005
French PolynesiaRestricted distributionSPC-PPS, 2003; Davis et al., 2005; IPPC, 2006
French PolynesiaPresentSPC-PPS, 2003; Davis et al., 2005; IPPC, 2006
Papua New GuineaPresentDavis et al., 2002
SamoaPresentCABI/EPPO, 2003
Solomon IslandsPresentSouth Pacific Commissionpersonal communication
TongaPresentSouth Pacific Commissionpersonal communication

Risk of Introduction

Top of page RISK CRITERIA CATEGORY

ECONOMIC IMPORTANCE High
DISTRIBUTION Worldwide
SEEDBORNE INCIDENCE Yes
SEED TRANSMITTED Disputed
SEED TREATMENT None

OVERALL RISK Low

Hosts/Species Affected

Top of page The host range of PRSV-P is limited to plants in the families Caricaceae, Cucurbitaceae and Chenopodiaceae.

In addition to the cultivated species Carica papaya, PRSV-P was also experimentally transmitted to C. goudotiana, C. horovitziana, C. microcarpa, C. monoica, C. parviflora and C. quercifolia (Conover, 1964a; Torres and Giacometti, 1966; Horovitz and Jiménez, 1967; Costa and Carvalho, 1971; Magdalita et al., 1988).

Within the family Cucurbitaceae, the following species were already tested with positive systemic infection with PRSV-P: Citrullus fistulosus; C. vulgaris [C. lanatus]; Cucumis anguria var. anguria, C. anguria var. longipes, C. melo var. reticulatus; C. metuliferus, C. sativus; Cucurbita maxima; C. pepo; C. pepo var. medullosa; C. pepo var. melopepo; C. moschata; Cyclanthera pedata; Diplocyclos palmatus; L. siceraria; Luffa acutangula; Melothria guadalupensis; M. pendula; Momordica charantia; and Trichosanthes anguina [T. cucumerina] (Capoor and Varma, 1948, 1958; Adsuar, 1950; Ishii and Holtzman, 1963; Conover, 1964b; Bokx, 1965; Story et al., 1968; Zettler et al., 1968; Costa et al., 1969; Cook, 1972; Pinto, 1972; Wang et al., 1978; Chang, 1979; Lana, 1980; Provvidenti and Gonsalves, 1982; Magdalita et al., 1990; Provvidenti, 1996; Kader et al., 1997).

Chenopodium amaranticolor and C. quinoa are reported as local lesion hosts of PRSV-P. However, local symptom expression on these species is apparently related to the virus strain and the 'variety' of the test plant.

Local lesions on both species have been reported for inoculation with PRSV-P strains from Ecuador, Florida (Yeh et al., 1984), Hawaii (Cook and Milbrath, 1971; Gonsalves and Ishii, 1980), India (Sureka et al., 1977), Nigeria (Lana, 1980) and Taiwan (Wang et al., 1978; Lin, 1980). Strains from Australia (Thomas and Dodman, 1993), Brazil (Lima and Gomes, 1975; A.S. Costa, Instituto Agronomico, Campinas, SP, Brazil, personal communication, 1985), Colombia (Sánchez de Luque and López, 1976, 1977), Dominican Republic (Story et al., 1968; Story and Halliwell, 1969) and Venezuela (Pinto, 1972) have failed to cause local symptoms on both species of Chenopodiaceae.

Rezende and Costa (1985) tested C. quinoa grown from seeds received from Taiwan, from the National Seed Storage Laboratory at Colorado State University, USA, and from a Brazilian stock. They showed that only plants originated from seeds obtained in the USA developed local lesions when inoculated with some Brazilian isolates of the virus. However, recent tests with other Brazilian isolates of PRSV-P failed to cause local lesions on the USA 'variety' of C. quinoa (J. A. M. Rezende, Universidade de Sao Paulo, Piracicaba, SP, Brazil, personal communication, 1983).

Growth Stages

Top of page Flowering stage, Fruiting stage, Seedling stage, Vegetative growing stage

Symptoms

Top of page Papaya plants are susceptible to PRSV-P at any age and generally show symptoms 2-3 weeks after inoculation.

Symptoms may vary in intensity according to the age at which the plant becomes infected and the strain of the virus. Leaf symptoms are characterized by intense yellow mosaic and leaf distortion. The leaf laminae are markedly reduced in size, and may develop a shoestring appearance. The reduction of the leaf laminae can be confused with that caused by broad mite (Polyphagotarsonemus latus). Dark-green blisters may be present and mosaic may also occur on leaves.

Oily streaks on the stem and petioles of the leaves are frequently observed on diseased plants. Dark-green rings are almost always present on fruits. The number of rings on the fruit can vary, and the rings become less distinct as the fruit mature and yellow.

The canopy of diseased plants become smaller due to the development of smaller leaves, reduced petioles and stunting.

Fruit yield of affected plants is markedly lower than that of healthy plants. Trees infected at a very young age never produce marketable fruit but rarely die, except when infected with certain strains from Taiwan that cause wilting and sometimes death of young papaya trees (Gonsalves, 1994).

List of Symptoms/Signs

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SignLife StagesType
Fruit / abnormal patterns
Leaves / abnormal colours
Leaves / abnormal forms
Leaves / abnormal patterns
Leaves / necrotic areas
Stems / discoloration of bark
Whole plant / dwarfing

Biology and Ecology

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PRSV-P is transmitted in nature by several species of aphids in a non-persistant manner (Adsuar, 1947b; Jensen, 1949b; Namba and Kawanishi, 1966; Acosta, 1969; Bhargava and Khurana, 1970; Namba and Higa, 1975, 1977, 1981; Hwang and Hsieh, 1984; Purcifull et al., 1984; Hsieh and Hwang, 1986; Taya and Singh, 1997). More than 20 species of aphids have been experimentally tested for PRSV-P transmission with positive results, including Myzus persicae, Aphis coreopsidis, A. craccivora, A. fabae, A. gossypii and Toxoptera citricidus.

Although several species of Cucurbitaceae are susceptible to PRSV-P, they are apparently not important as alternative hosts for the virus. The spread of PRSV-P into and within an orchard is primarily from papaya to papaya. The introduction of the virus into a new orchard always comes from outside, primarily from diseased papaya trees. The amount of primary infection is directly related to the distance from the infected papaya (Wolfenbarger, 1966). Once the virus is introduced into the orchard, secondary infection will occur and all plants can become infected in 3-7 months (Ishii, 1972; Conover, 1976; Barbosa and Paguio, 1982; Rezende and Costa, 1984). A slower spread of PRSV-P can occur in areas with a reduced population of aphids, as was reported for a partially isolated region of Sao Paulo, Brazil (Rezende et al., 1986, 1987; Yuki et al., 1987).

Means of Movement and Dispersal

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Natural Dispersal (Non-Biotic)

Unknown.

Vector Transmission

This is the most important and efficient way of transmission of PRSV, through short and long distance. Several species of aphids can transmit this virus. The virus-vector relationship is non-persistant (Adsuar, 1947b; Jensen, 1949b; Namba and Kawanishi, 1966; Acosta, 1969; Bhargava and Khurana, 1970; Namba and Higa, 1975, 1977, 1981; Hwang and Hsieh, 1984; Purcifull et al., 1984; Hsieh and Hwang, 1986; Taya and Singh, 1997). More than 20 species of aphids have been experimentally tested for PRSV-P transmission with positive results, including Myzus persicae, Aphis coreopsidis, A. craccivora, A. fabae, A. gossypii and Toxoptera citricida. Weed hosts in papaya orchards may serve as reservoirs of aphid vectors of PRSV-P (Martins et al., 2016). 

Seedborne Spread

Until recently there was no experimental evidence to suggest that PRSV-P was seed-transmissible. However, tests carried out by Bayot et al. (1990) in the Philippines showed that two out of 1335 seedlings (0.15%) of 'Cavite' papaya grown from seeds taken from PRSV-P infected fruits showed symptoms similar to those of papaya ringspot. In another study, no seed transmission of the virus was detected in papaya (Prasad and Sarkar, 1989).

Agricultural Practices

Not known to be involved on the transmission of PRSV in the field.

Seedborne Aspects

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Tripathi et al. (2008) reported that PRSV is typically not seed transmitted; however, Laney et al. (2012) recorded a high incidence of seed transmission of the virus in Robinia pseudoacacia.

Pathogen Transmission

Tests carried out by Bayot et al. (1990) in the Philippines showed that two out of 1335 seedlings (0.15%) of 'Cavite' papaya grown from seeds taken from PRSV-P infected fruits showed symptoms similar to those of papaya ringspot. In another study, no seed transmission of the virus was detected in papaya (Prasad and Sarkar, 1989). Further studies are required for confirmation of seed transmissibility of PRSV-P.

Laney et al. (2012) reported a high incidence of seed transmission of PRSV in black locust (R. acacia) suggesting that this may be an important route for virus dissemination.

Plant Trade

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Plant parts liable to carry the pest in trade/transportPest stagesBorne internallyBorne externallyVisibility of pest or symptoms
Flowers/Inflorescences/Cones/Calyx Yes Pest or symptoms usually invisible
Fruits (inc. pods) Yes Pest or symptoms usually visible to the naked eye
Leaves Yes Pest or symptoms usually visible to the naked eye
Roots Yes Pest or symptoms usually invisible
Seedlings/Micropropagated plants Yes Pest or symptoms usually visible to the naked eye
Stems (above ground)/Shoots/Trunks/Branches Yes Pest or symptoms usually invisible
Plant parts not known to carry the pest in trade/transport
Bark
Bulbs/Tubers/Corms/Rhizomes
Growing medium accompanying plants
True seeds (inc. grain)
Wood

Impact

Top of page PRSV-P causes one of the most destructive diseases of papaya in nearly every region of the world where papaya is grown. The decline of the papaya industry due to papaya ringspot disease has been observed in some regions. In Taiwan, PRSV-P was first recorded in 1975 and within 4 years the virus had destroyed most of the papaya production along the west coast of the island. The total yield of papaya dropped from 41,595 tons in 1974 to 18,950 tons in 1977 (Yeh et al., 1988).

In Southern Tagalog, Philippines, where the virus was first detected in 1982, papaya production was reduced drastically from 36,000 metric tons in 1981 to 10,000 metric tons in 1987 (Bayot et al., 1990).

In Brazil, the disease caused by PRSV-P was responsible for the almost total disappearance of the papaya crop from the state of Sao Paulo. The area planted with papaya trees was reduced from aproximately 7188 ha in 1977 to 4374 ha in 1980, 906 ha in 1986 and 234 ha in 1989.

Diagnosis

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Symptoms induced by PRSV-P in Carica papaya can be used for detection and diagnosis, although they show certain variation depending on the stage of infection, plant vigour, temperature, virus strain and plant size. Key symptoms are the intense mosaic on leaves and the presence of oily streaks on the stems and petioles. Another key symptom, for plants bearing fruits, is dark-green rings on fruits.

The virus is a good immunogen and antisera with high titres have been produced. Liquid immunoprecipitin test (Webb and Scott, 1965), SDS-immunodiffusion test (Purcifull and Hiebert, 1979; Gonsalves and Ishii, 1980), ELISA (Gonsalves and Yshii, 1980; Ben-Ze'ev et al., 1988; Husain, 1997) and immunosorbent electron microcopy (ISEM) can be used for the detection of virus in infected tissues.

Particle morphology and cytoplasmic inclusions in the host tissue, viewed by electron microscopy, may also be used in diagnosis. Cytoplasmic inclusions are of two types: cylindrical and amorphous. The cylindrical inclusions are striated, with a periodicity of 5 nm, and are associated with scrolls. They aggregate to form fibrous structures that are clearly visible by light microscopy of epidermal strips stained with luxol brilliant green-calcomine orange (Purcifull et al., 1984).

RT PCR is identified as a rapid and important diagnosis method for PRSV by Vucurovic et al. (2009).

Detection and Inspection

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Symptoms of the disease are very characteristic and easily visible on plants infected in the field. During the early stage of infection PRSV can be identified by the presence of oily stains in the base of the petioles and in the stem (Cortez-Madrigal and Mora-Aguilera, 2007). When confirmation of the disease agent is required, leaf samples should be collected for identification using the methods described under Diagnostic methods.

Prevention and Control

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Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.

Introduction

Due to the economic importance of the papaya crop and the damage caused by papaya ringspot disease, scientists from different parts of the world have made efforts to develop methods to control or minimize the effects of the disease on papaya production. Different approaches have been investigated, such as planting in partially isolated areas and roguing; planting under screenhouses; breeding for resistance or tolerance to the virus; using virus-resistant transgenic plants; and cross protection.

Cultural Control

Planting in partially isolated areas and roguing
PRSV may be controlled by preventive practices that reduce or delay the spread of the virus within the orchard. These practices include the use of virus-free seedlings to start new crops, planting in partially isolated areas or as far as possible from old infected papayas, roguing of diseased plants once every 2 weeks, avoidance of cucurbit plants in or near the orchard, and systematic weed control to reduce the aphid population (Costa et al., 1969; Ishii, 1972; Martinez, 1980; Gonsalves, 1994). Practical application of these measures, especially roguing of diseased plants, has been reported in Hawaii (Namba and Higa, 1977; Gonsalves, 1994). In Brazil, roguing of diseased papayas allowed satisfactory control of the disease in orchards in Espírito Santo for more than 10 years, with an eradication rate of between 5 and 10% of diseased trees per year (JA Ventura, EMCAPA, Vitoria, ES, Brazil, personal communication, 1986). Due to the effectiveness of this practice, the state of Espírito Santo passed a law which requires all growers to adopt roguing of diseased papayas for control of the disease; failure to follow the rules can result in complete elimination of the orchard by official authorities.

In Sao Paulo, Brazil, Rezende et al. (1986, 1987) demonstrated that papayas could be grown satisfactorily in certain areas in the Ribeira Valley, which is situated in the south-east of the state between the coastal mountain range and the ocean. The spread of the virus in this region is slower than in other parts of the state due to the reduced aphid population and the partial isolation of areas with native forest (Yuki et al., 1987).

Planting under screenhouse
Several studies have been carried out in order to find chemical or physical methods of protecting papaya trees from aphid vectors. These methods include the use of insecticides, mineral oils, and protective barriers of other species of plants (Acosta, 1969; Harkness, 1967; Nakasone, 1980; Becerra Leon, 1989). None of these methods have been sufficiently effective in controlling papaya ringspot because of the large number of aphid species that may act as vectors and their non-persistant relationship with the virus.

Another alternative is to prevent viruliferous aphids landing on papaya trees by planting the crop under screenhouses. This technique was first tried in Taiwan and has produced satisfactory results (Rezende and Costa, 1995). Sheen et al. (1998) reported that Taiwan has more than 1000 ha of papayas growing under screenhouses (net-house) annually. The incidence of PRSV-P in the screenhouse was 0.3%, 6 months after transplanting, compared to 96% plants infected in the field.

Planting date and mineral nutrition
Studies in India have shown that transplanting papaya in October, with heavy but balanced fertilization, helped reduce the incidence and severity of papaya ringspot disease in plantations. The best fertilization dose consisted of 10 kg FYM, 2 kg castor cake, 1 kg cake-0-meal, 200 g N, 200 g K2O and 200 g P2O5 (Kudada and Prasad, 1999; Ray et al., 1999).

Effective microorganisms (EM), a mixture of beneficial microoganisms including lactic acid bacteria, yeasts, actinomycetes and photosynthetic bacteria, have been reported to reduce papaya ringspot incidence in Taiwan (Tsai, 1998).

Host-Plant Resistance

Resistance to PRSV-P does not occur within Carica papaya. Although high levels of resistance or immunity have been found in some wild species of Carica, interspecific reproductive barriers make it difficult to incorporate resistance genes into C. papaya (Horovitz and Jiménez, 1967; Nagai, 1980; Nakasone, 1980; Magdalita et al., 1988, 1997; Manshardt and Wenslaff, 1989a, b; Chen et al., 1991; Fitch et al., 1992; Drew et al., 1998).

The development of tolerant cultivars of C. papaya has minimized the damage caused by papaya ringspot. Conover et al. (1986) developed the cultivar Cariflora, which is tolerant to papaya ringspot in southern Florida, USA, and the Caribbean. In Taiwan, Lin et al. (1989) reported the development of the hybrid Tainung No. 5 with good level of tolerance to the disease and horticultural characteristics that satisfy both farmers and consumers.

Cross Protection

Cross protection has been used for the control of papaya ringspot in different countries with varying degrees of success. This technique involves the inoculation of papaya seedlings with a mild strain which protects plants against damage caused by infection with a severe strain of the virus in the field.

A nitrous acid-induced mutant of PRSV-P from Hawaii, designated HA 5-1, was introduced into Taiwan and used to protect papaya trees in the field (Yeh and Gonsalves, 1984, 1994; Yeh et al., 1988). Although cross protection has helped papaya growers to produce a fruitful crop during 8 years, there are several drawbacks including adverse effects of mild strains on papaya under cool and rainy conditions; the additional cost of inoculating and indexing the seedlings; difficulties in propagation and preservation of the inoculum; the possible occurrence of severe revertants; breakdown under severe disease pressure; and strain-specific protection (Yeh and Gonsalves, 1994; Sheen et al., 1998). Currently, the mild strain is sparsely used in Taiwan, mainly because it does not provide consistent economic returns to farmers (Gonsalves, 1998).

Extensive field trials on the Island of Oahu, Hawaii showed that cross protection with the mild strain HA 5-1 was more effective in Hawaii than in Taiwan, as protection is strain-specific. The mild strain HA 5-1 was selected from a common strain from Hawaii and therefore offers better protection against the parental strain. The mild strain HA 5-1 gave good protection in field experiments, although it produced noticeable symptoms on leaves and fruits, with the degree of symptom severity markedly dependent on the cultivar (Gonsalves, 1998). Cross protection has not been widely adopted on Oahu for several reasons including adverse effects of the mild strain on papaya cultivars, the extra cultural management and care required, and the reluctance of farmers to infect their trees with a virus (Gonsalves, 1998). The introduction of the mild strain to Thailand and Mexico did not show promising results, apparently due to strain-specific protection (Yeh and Gonsalves, 1994; Gonsalves, 1998).

In Brazil, attempts to control papaya ringspot by cross protection have failed due to the apparent instability of the selected mild strains (Rezende, 1985; Rezende and Costa, 1987; Rezende and Costa 1995; Rezende and Müller, 1995).

Transgenic papaya

The development of transgenic papaya, containing the coat protein gene of PRSV-P, has offered a new approach for controlling papaya ringspot. The first successful effort to develop transgenic papaya resistant to PRSV-P was initiated in late 1980s through a co-operative project involving Cornell University, the UpJohn Company, the University of Hawaii and the Papaya Administrative Committee from Hawaii (Gonsalves, 1998). Fitch et al. (1990, 1992) obtained a Sunset Solo-derived transgenic line, named 55-1, that expressed the coat protein gene from the mild strain PRSV-P HA 5-1, which was highly resistant to Hawaiian strains of the virus, but susceptible to strains outside Hawaii (Tennant et al., 1994). The transgenic papaya showed excellent resistance throughout the 2-year field trial in Hawaii (Lius et al., 1997). In 1998, two trangenic papaya varieties resistant to PRSV-P, Rainbow and Sun Up, were commercially released in the USA. Sun Up is line 55-1, which is homozygous for the coat protein transgene, and Rainbow is an F1 hybrid between Sun Up and the yellow-fresh variety, Kapoho Solo. These trangenic, resistant varieties promise to revive the Hawaiian papaya industry (Gonsalves, 1998).

Further studies with transgenic papaya have shown a breadth of resistance reactions to PRSV-P strains. Tennant et al. (1997) showed that SunUp has a broader spectrum of resistance than Rainbow or the R1 hemizygous 55-1, suggesting that gene dosage affects the resistance. Sunset Solo-derived transgenic line 63-1 has shown resistance to PRSV-P isolates from Brazil and Thailand (Souza et al., 1998; Souza, 1999). Yeh et al. (1997) obtained transgenic papaya expressing the coat protein gene from a Taiwanese PRSV-P isolate and resistant to isolates from Taiwan, Hawaii and Thailand. The production of PRSV-P resistant transgenic papaya plants expressing untranslatable versions of the coat protein gene (Souza and Gonsalves, 1998; Cai et al., 1999), together with results from northern blots and nuclear run on assays from line 55-1 (Tennant et al., 1997; Souza, 1999) suggested that post transcriptional gene silencing is the underlaying mechanism for the PRSV:transgenic papaya resistance system.

In 1992, a collaborative effort was initiated between Cornell University and the National Center for Research in Cassava and Tropical Fruits (CNPMF, EMBRAPA, Cruz das Almas, BA, Brazil) with the objective of developing transgenic papaya expressing the coat protein gene of a Brazilian isolate of PRSV-P. An initial evaluation revealed that some phenotypes were apparently immune to Brazilian isolates of the virus. The first field trial with transgenic papaya in Brazil was initiated in January 2000 (Souza and Gonsalves, 1998, 1999; Souza, 2000).

New transgenic lines expressing the coat protein genes of PRSV-P isolates from Jamaica, Thailand and Australia have been produced (Gonsalves, 1998).

According to Gonsalves (1998), proof of success in controlling papaya ringspot throughout transgenic resistant plants will be determined in the next few years, as the transgenic papaya is currently widely planted in Hawaii and as more transgenic papaya is produced and tested worldwide.

References

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Acosta JCM, 1969. Consideraciones sobre insectos vectores aphididae y la "deformacion foliar" (distortion ringspot virus) de Carica papaya en el Limon, Estado Aragua, Venezuela. Revista de la Facultad de Agronomia, Universidad Central de Venezuela, 3:77-108.

Acu±a J; De Zayas F, 1940. Fruta bomba o papaya. Revista de Agricultura (Cuba), 23:49-80.

ADSUAR J, 1947. Studies on virus diseases of Papaya (Carica papaya) in Puerto Rico. I. Property studies of Papaya mosaic virus. Journal of Agriculture of the University of Puerto Rico, 31(3):260-264.

ADSUAR J, 1947. Studies on virus diseases of Papaya (Carica papaya) in Puerto Rico. I. Transmission of Papaya mosaic. Journal of Agriculture of the University of Puerto Rico, 31(3):248-256.

ADSUAR J, 1947. Studies on virus diseases of Papaya (Carica papaya) in Puerto Rico. II. Transmission of Papaya mosaic by the green Citrus aphid (Aphis spiraecola Patch). Journal of Agriculture of the University of Puerto Rico, 31(3):257-259.

Adsuar J, 1950. Studies on virus diseases of papaya (Carica papaya) in Puerto Rico. IV. Preliminary studies on the host range of papaya mosaic. Agricultural Experiment Station, University of Puerto Rico. Technical Paper No. 5.

Akanda AM; Tsuno K; Wakimoto S, 1991. Serological detection of four plant viruses in cucurbitaceous crops from Bangladesh. Annals of the Phytopathological Society of Japan, 57(4):499-505

Alhubaishi AA; Walkey DGA; Webb MJW; Bolland CJ; Cook AA, 1987. A survey of horticultural plant virus diseases in the Yemen Arab Republic. FAO Plant Protection Bulletin, 35(4):135-143

Ali A; Natsuaki T; Okuda S, 2004. Identification and molecular characterization of viruses infecting cucurbits in Pakistan. Journal of Phytopathology, 152(11/12):677-682. http://www.blackwellpublishing.com/jph

Almeida AMR; Carvalho SLC, 1978. OcorrOncia do vfrus do mosaico do mamoeiro no Estado do Paran . Fitopatologia Brasileira, 3:65-68.

AVA, 2001. Diagnostic records of the Plant Health Diagnostic Services, Plant Health Centre, Agri-food & Veterinary Authority, Singapore.

Baker RED, 1938. Papaw mosaic diseases. Tropical Agriculture (Trinidad), 16:159-163.

Barbosa FR; Paguio OR, 1982. Vfrus da mancha anelar do mamoeiro: IncidOncia e efeito na produtao do mamoeiro (Carica papaya L.). Fitopatologia Brasileira, 7:365-373.

Bateson M; Dale J, 1992. The nucleotide sequence of the coat protein gene and 3' untranslated region of papaya ringspot virus type W (Aust). Archives of Virology, 123(1-2):101-109

Bateson MF; Henderson J; Chaleeprom W; Gibbs AJ; Dale JL, 1994. Papaya ringspot potyvirus: isolate variability and the origin of PRSV type P (Australia). Journal of General Virology, 75(12):3547-3553

Bayot RG; Villegas VN; Magdalita PM; Jovellana MD; Espino TM; Exconde SB, 1990. Seed transmissibility of papaya ringspot virus. Philippine Journal of Crop Science, 15(2):107-111

Becerra Leor EN, 1989. Preferred colour in papaya plants (Carica papaya L.) and roselle plant (Hibiscus sabdariffa L.) barriers as means for reducing papaya virosis transmission by aphids. Revista Mexicana de Fitopatologia, 7(2):218-222

Ben-Ze'ev IS; Frank A; Bar-Joseph M, 1988. Sensitive detection of two plant viruses by enzyme-amplified ELISA. Phytoparasitica, 16(4):343-349

Bhargava KS; Khurana SMP, 1970. Insect transmission of papaya viruses with special reference to papaya mosaic virus. Zentralblatt für Bakteriologie, Parasitenkunden Infektionskrankeiten und Hygiene, 124:688-696.

Bokx JA, 1965. Host and electron microscopy of two papaya viruses. Plant Disease Reporter, 49:742-746.

Brunt AA; Crabtree K; Dallwitz MJ; Gibbs AJ; Watson L (eds), 1996. Viruses of plants. Descriptions and lists from the VIDE database. Wallingford, UK: CAB INTERNATIONAL, 1484 pp.

CABI/EPPO, 2003. Papaya ringspot virus. Distribution Maps of Plant Diseases, No. 902. Wallingford, UK: CAB International.

Cai W; Gonsalves C; Tennant P; Fermin G, Souza Jr. MT, Saridu N, Jan FL, Zhu HY, Gonsalves D, 1999. A protocol for efficient transformation and regeneration of Carica papaya L. In Vitro Cellular & Development Biology - Plant 35:61-69.

Capoor SP; Varma PM, 1948. A mosaic disease of Carica papaya L. in the Bombay province. Current Science, 17:265-266.

Capoor SP; Varma PM, 1958. A mosaic disease of papaya in Bombay. Indian Journal of Agricultural Science, 27:225-233.

Chang CA, 1979. Isolation and comparison of two isolates of papaya ringspot virus in Taiwan. Journal of Agricultural Research of China, 28:207-216.

Chen MH; Chen CC; Wang DN; Chen FC, 1991. Somatic embryogenesis and plant regeneration from immature embryos of Carica papaya x Carica cauliflora cultured in vitro. Canadian Journal of Botany, 69:1913-1918.

Chin M; Rhodes L; Tennant P, 2008. Outbreak of Papaya ringspot virus in papaya orchards, in St. Kitts. Plant Pathology, 57(4):767. http://www.blackwell-synergy.com/loi/ppa

Ciferri R, 1930. Phytopathological survey of Santo Domingo. Journal of the Department of Agriculture of Puerto Rico, 14:5-44.

Conover RA, 1964. Distortion ringspot, a severe virus disease of papaya in Florida. Proceedings, Florida State Horticultural Society, 77:440-444.

Conover RA, 1964. Mild mosaic and faint mottle ringspot, two papaya virus diseases of minor importance in Florida. Proceedings of the Florida State Horticultural Society, 77:444-448.

Conover RA, 1976. A program for development of papayas tolerant to the distortion ringspot virus. Proceedings of the Florida State Horticultural Society, 89:229-231

Conover RA; Litz RE, 1978. Progress in breeding papayas with tolerance to papaya ringspot virus. Proceedings of the Florida State Horticultural Society, 91:182-184

Conover RA; Litz RE; Malo SE, 1986. `Cariflora'- a papaya ringspot virus-tolerant papaya for South Florida and the Caribbean. HortScience, 21:1072.

Cook AA, 1972. Virus diseases of papaya. Technical Bulletin, Institute of Food and Agricultural Sciences, Florida Agricultural Experiment Stations, No. 750:19 pp.

Cook AA; Milbrath GM, 1971. Virus diseases of papaya on Oahu (Hawaii) and identification of additional disgnostic host plants. Plant Disease Reporter, 55:785-788.

Cortez-Madrigal H; Mora-Aguilera G, 2007. Incidence of Papaya ringspot virus and aphid pupulations in Tabasco, Mexico. (Incidencia del virus de la mancha anular del papayo y captura de áfidos alados en Tabasco, México.) Manejo Integrado de Plagas y Agroecología, No.79/80:29-35.

Costa AS; Carvalho AM, 1971. O problema da resistOncia ao mosaico do mamoeiro. Revista da Sociedade Brasileira de Fitopatologia, 4:37-38.

Costa AS; Carvalho AM; Kamada S, 1969. Constatado o mosaico do mamoeiro em Sao Paulo. O Agronômico, 21:38-43.

Davis RI; Mu L; Maireroa N; Wigmore WJ; Grisoni M; Bateson MF; Thomas JE, 2005. First records of the papaya strain of Papaya ringspot virus (PRSV-P) in French Polynesia and the Cook Islands. Australasian Plant Pathology, 34(1):125-126.

Davis RI; Thomas JE; McMichael LA; Dietzgen RG; Callaghan B; James AP; Gunua TG; Rahamma S, 2002. Plant virus surveys on the island of New Guinea and adjacent regions of northern Australia. Australasian Plant Pathology, 31(4):385-390; 34 ref.

Diallo HA; Monger W; Kouassi N; Yoro DT; Jones P, 2007. First report of Papaya ringspot virus infecting papaya in Côte d'Ivoire. Plant Pathology, 56(4):718. http://www.blackwell-synergy.com/loi/ppa

Drew RA; O'Brien CM; Magdalita PM, 1998. Development of Carica interspecific hybrids. Acta Horticulturae, No. 461:285-291; 11 ref.

EPPO, 2012. EPPO Reporting Service. EPPO Reporting Service. Paris, France: EPPO. http://archives.eppo.org/EPPOReporting/Reporting_Archives.htm

Escudero J; Acosta A; Ramirez LV; Caloni IB; Sifre GR, 1994. Yield in three papaya genotypes and their tolerance to papaya ringspot virus in Puerto Rico. Journal of Agriculture of the University of Puerto Rico, 78(3/4):111-121

Espinoza HR; McLeod PJ, 1994. Use of row cover in cantaloupe (Cucumis melo L.) to delay infection of aphid-transmitted viruses in Honduras. Turrialba, 44(3):179-183

Fauquet CM; Martelli GP, 1995. Updated ICTV list of names and abbreviations of viruses, viroids, and satellites infecting plants. Archives of Virology, 140(2):393-413.

Fernandes FF; Valverde RA; Black LL, 1991. Viruses infecting cucurbit crops in Louisiana. Plant Disease, 75(4):431

Fitch MMM; Manshardt RM; Gonsalves D; Slightom JL; Sanford JC, 1990. Stable transformation of papaya via microprojectile bombardment. Plant Cell Report 9:189-194.

Fitch MMM; Manshardt RM; Gonsalves D; Slightom JL; Sanford JC, 1992. Virus resistant papaya plants derived from tissues bombarded with the coat protein gene of papaya ringspot virus. Bio/Technology, 10(11):1466-1472

Gonsalves D, 1994. Papaya diseases caused by virus. In: Ploetz RC, Zentmyer GA, Nishijima WT, Rohrbach KG, Ohr HD, eds. Compendium of Tropical Fruit Diseases. St. Paul, Minnesota, USA: APS Press, 66-68.

Gonsalves D, 1998. Control of papaya ringspot virus in papaya: a case study. Annual Review of Phytopathology, 36:415-437; 65 ref.

Gonsalves D; Ishii M, 1980. Purification and serology of papaya ringspot virus. Phytopathology, 70(11):1028-1032

Gourgopal Roy; Jain RK, 2002. Comparison of the coat protein genes of two papaya ringspot virus isolates with other isolates from different geographic locations. Indian Phytopathology, 55(3):335-337.

Gu QinSheng; Tian YanPing; Peng Bin; Liu LiFeng; Deng CongLiang; Liang XinMiao; Meng Juan, 2008. Molecular analysis of three cucurbit viruses based on coat protein gene sequences. Acta Phytopathologica Sinica, 38(4):357-363. http://zwblxb.periodicals.net.cn/default.html

Gude SR; Nagaraju; Pankaja NS; Ravikumar B; Anjula N, 2008. Occurrence of a strain of Papaya ring spot virus on cucurbitaceous crops around Bangalore. Environment and Ecology, 26(3):1066-1069.

Gungoosingh-Bunwaree A, 2001/2002. Status of major viruses affecting cucurbitaceous crops in Mauritius. Revue Agricole et Sucrière de l'Île Maurice, 80/81(3-1/3):98-103.

Halfeld-Vieira BA; Ramos NF; Rabelo Filho FAC; Gonçalves MFB; Nechet KL; Pereira PRVS; Lima JAA, 2004. Serological identification of virus species in watermelon in the state of Roraima. (Identificação sorológica de espécies de potyvirus em melancia, no estado de Roraima.) Fitopatologia Brasileira, 29(6):687-689. http://www.scielo.br/pdf/fb/v29n6/a18v29n6.pdf

Hander CA; McLeod PJ; Scott HA, 1993. Incidence of aphids (Homoptera: Aphididae) and associated potyviruses in summer squash in Arkansas. Journal of Entomological Science, 28(1):73-81.

Harkness RW, 1967. Papaya growing in Florida. Agricultural Experiment Station, Institute of Food and Agricultural Sciences, University of Florida. Circular S-180.

Hasiów-Jaroszewska B; Borodynko N; Rymelska N; Pospieszny H, 2010. First report of Papaya ringspot virus infecting zucchini plants in Poland. Plant Disease, 94(5):633. http://apsjournals.apsnet.org/loi/pdis

Hendrix JW, 1948. The influence of papaya ringspot on the growth and yield of papaya trees. Report of the Hawaii Agricultural Experiment Station, University of Hawaii. 1946-1948.

Herold F; Weibel J, 1962. Electron microscopic demonstration of papaya ringspot virus. Virology, 18:302-311.

Higa SY; Namba R, 1970. Vectors of the papaya mosaic virus in Hawaii. Proceedings of the Hawaiian Entomological Society, 21(1):93-96

Holmes FO; Hendrix JW; Ikeda W; Jensen DD; Lindner RC; Storey WB, 1948. Ringspot of papaya (Carica papaya) in the Hawaiian Islands. Phytopathology, 38:310-312.

Horovitz S; JimTnes H, 1967. Cruzamientos interspecificos e intergenericos en Caricaceaes y sus implicaciones fitotecnicas. Agronomia Tropical (Venezuela), 17:323-343.

Hsieh FK; Hwang JS, 1986. Some ecological aspects of the green peach aphid transmitting papaya ringspot virus in Taiwan. Plant Protection Bulletin, Taiwan, 28(3):273-287

Hwang JS; Hsieh FK, 1984. Studies on aphid transmission of papaya ringspot virus. Plant Protection Bulletin, Taiwan, 26(4):395-400

IPPC, 2006. IPP Report No. PF-5/1. Rome, Italy: FAO.

IPPC, 2006. IPP Report No. PF-6/1. Rome, Italy: FAO.

Ishii M, 1972. Observation on the spread of papaya ringspot virus in Hawaii. Plant Disease Reporter, 56:331-333.

Ishii M; Holtzman OV, 1963. Papaya mosaic disease in Hawaii. Plant Disease Reporter, 47:947-951.

Jain RK; Pappu HR; Pappu SS; Varma A; Ram RD, 1998. Molecular characterisation of papaya ringspot potyvirus isolates from India. Annals of Applied Biology, 132(3):413-425; 31 ref.

Jensen DD, 1949. Papaya ringspot virus and its insect vector relationships. Phytopathology, 39:212-220.

Jensen DD, 1949. Papaya virus disease with special reference to papaya ringspot. Phytopathology, 39:191-211.

Jyoti Sharma; Jain RK; Ramiah M; Varma A, 2005. Natural spread of Papaya ringspot virus to new areas: occurrence in Coimbatore, Tamil Nadu. Indian Phytopathology, 58(2):245-249.

Kader KA; Muqit A; Akanda AAM, 1997. Detection of plant viruses from ribbed gourd. Bangladesh Journal of Plant Pathology, 13(1/2):39-40; 11 ref.

Katul L; Makkouk KM, 1987. Occurrence and serological relatedness of five cucurbit potyviruses in Lebanon and Syria. Phytopathologia Mediterranea, 26(1):36-42

Kitajima EW; Mattos JKA; Parente TV; Marinho VLA, 1986. OcorrOncia do vfrus do mosaico do mamoeiro ("papaya ringspot virus") no Distrito Federal. Fitopatologia Brasileira, 11:357.

Kitajima EW; Ribeiro R de LD; Lin MT; Ribeiro MISD; Kimura O; Costa CL; Pimentel JP, 1984. Annotated list of viruses and mycoplasma-like organisms on cultivated and wild plants in the State of Rio de Janeiro. Fitopatologia Brasileira, 9(3):607-625

Ko C; Chen H; Chen YC; Chang LJ, 1979. Electron microscopic observations of papaya ringspot mosaic disease in Fujian. Acta Phytopathologica Sinica, 9(1):31-34; 65-66

Kudada N; Prasad SM, 1999. Effect of planting time on the incidence of papaya ringspot virus disease and yield of fruits. Indian Phytopathology 52(3):224-227.

Köklü G; Yilmaz Ö, 2006. Occurrence of cucurbit viruses on field-grown melon and watermelon in the Thrace region of Turkey. Phytoprotection [Proceedings of meetings of the Quebec Society for Plant Protection. Quebec, Canada.], 87(3):123-130. http://www.phytoprotection.ca

Lana AF, 1980. Transmission and properties of viruses isolated from Carica papaya in Nigeria. Journal of Horticultural Science, 55(2):191-197

Laney AG; Avanzato MV; Tzanetakis IE, 2012. High incidence of seed transmission of Papaya ringspot virus and Watermelon mosaic virus, two viruses newly identified in Robinia pseudoacacia. European Journal of Plant Pathology, 134(2):227-230. http://springerlink.metapress.com/link.asp?id=100265

Lima JAA; Gomes MNS, 1975. Identification of papaw ringspot virus in Fortaleza, Ceara. Fitossanidade, 1(2):56-59

Lin CC, 1980. Strains of papaya ringspot virus and their cross protection. PhD Thesis. Taipei, Taiwan: National Taiwan University.

Lin CC; Su HJ; Wang DN, 1989. The control of papaya ringspot virus in Taiwan R.O.C. Technical Bulletin - ASPAC, Food and Fertilizer Technology Center, No. 114:1-13

Lius S; Manshardt RM; Fitch MMM; Slightom JL; Sanford JC; Gonsalves D, 1997. Pathogen-derived resistance provides papaya with effective protection against papaya ringspot virus. Molecular Breeding, 3(3):161-168; 19 ref.

Lokhande NM; Moghe PG, 1991. Nutrients and hormonal effect on growth promotion and productivity in ringspot infected papaya crop. South Indian Horticulture, 39(1):23-26

Lu YaWei; Shen WenTao; Tang QingJie; Niu YanMei; Zhou Peng, 2008. Sequence analysis of the complete genome of papaya ringspot virus Hainan isolate. Chinese Journal of Virology, 24(2):152-154.

Magdalita PM; Bayot RG; Villegas VN, 1990. Diplocyclos palmatus L. Jeffrey: a new weed host of papaya ringspot virus. Philippine Journal of Crop Science, 15(3):163-168

Magdalita PM; Persley DM; Godwin ID; Drew RA; Adkins SW, 1997. Screening Carica papaya x C. cauliflora hybrids for resistance to papaya ringspot virus-type P. Plant Pathology, 46(6):837-841; 24 ref.

Magdalita PM; Villegas VN; Pimentel RB; Bayot RG, 1988. Reaction of papaya (Carica papaya L.) and related Carica species to ringspot virus. Pilippine Journal of Crop Science, 13(3):129-132

Manshardt RM; Wenslaff TF, 1989. Enterspecific hybridization of papaya with other Carica species. Journal of the American Society for Horticultural Science, 114:689-694.

Manshardt RM; Wenslaff TF, 1989. Zygotic polyembryony in interspecific hybrids of Carica papaya and C. cauliflora. Journal of the American Society for Horticultural Science, 114:684-689.

Maoka T; Kawano S; Usugi T, 1995. Occurrence of the P strain of papaya ringspot virus in Japan. Annals of the Phytopathological Society of Japan, 61(1): 34-37.

Martinez JA, 1980. Estudo da viabilidade prática e econômica do controle das viroses do mamoeiro pela erradicatao sistem tica das plantas afetadas. In: Anais 1° Simpósio brasileiro sobre a cultura do mamoeiro. Faculdade de CiOncias Agrárias e Veterinária, Jaboticabal, Brazil, 211-217.

Martins Ddos S; Ventura JA; Paula Rde CAL; Fornazier MJ; Rezende JAM; Culik MP; Ferreira PSF; Peronti ALBG; Carvalho RCZde; Sousa-Silva CR, 2016. Aphid vectors of Papaya ringspot virus and their weed hosts in orchards in the major papaya producing and exporting region of Brazil. Crop Protection, 90:191-196. http://www.sciencedirect.com/science/journal/02612194

Martorell LF; Adsuar J, 1952. Insects associated with papaya virus diseases in the Antilles and Florida. Journal of Agriculture of the University of Puerto Rico, 36:319-329.

McMillan Jr RT; Gonsalves D; Kendal PHJ, 1990. Commercial use of cross-protection by a mild mutant of papaya ringspot virus for control of ringspot disease of Solo papaya in the Bahamas. Proceedings, Florida State Horticultural Society, 103:318.

Mederos DC; Giolitti FJ; Portal O, 2015. First report of Papaya ringspot virus w infecting Momordica charantia in Cuba. Journal of Plant Pathology, 97(1):211. http://sipav.org/main/jpp/index.php/jpp/article/view/3282

Miller ME, 1989. Virus diseases of muskmelons in the Lower Rio Grande Valley. Journal of the Rio Grande Valley Horticultural Society, 42:19-23

Mnari-Hattab M; Jebari H; Zouba A, 2008. Identification and distribution of viruses responsible for mosaic diseases affecting cucurbits in Tunisia. (Identification et distribution des virus responsables de mosaiques chez les cucurbitacées en Tunisie.) Bulletin OEPP/EPPO Bulletin, 38(3):497-506. http://www.blackwell-synergy.com/loi/epp

Mora-Aguilera G; Nieto-Angel D; Teliz D; Campbell CL, 1993. Development of a prediction model for papaya ringspot in Veracruz, Mexico. Plant Disease, 77(12):1205-1211

Murphy FA; Fauquet CM; Bishop DHL; Ghabrial SA; Jarvis AW; Martelli GP; Mayo MA; Summers MD, 1995. Virus taxonomy: classification and nomenclature of viruses. Sixth report of the International Committee on Taxonomy of Viruses. Virus taxonomy: classification and nomenclature of viruses. Sixth report of the International Committee on Taxonomy of Viruses., viii + 586 pp.; [^italic~Archives of Virology, Supplement 10^roman~].

Nagai H, 1980. Espécies de Carica sp. resistentes ao mosaico. In: Anais 1° Simpósio brasileiro sobre a cultura do mamoeiro. Faculdade de CiOncias Agrárias e Veterinária, Jaboticabal, Brazil, 219-224.

Nakano DH; Sansini DMF; Buriolla JE; Junqueira NTV; Kitajima EW; Rezende JAM, 2008. Psiguria triphylla: a new natural host of Papaya ringspot virus - type W in Brazil. Plant Pathology, 57(2):398. http://www.blackwell-synergy.com/doi/abs/10.1111/j.1365-3059.2007.01629.x

Nakasone HY, 1980. A situanao do vfrus do mamao no Havaf. In: Anais 1° Simpósio brasileiro sobre a cultura do mamoeiro. Faculdade de CiOncias Agrárias e Veterinária, Jaboticabal, Brazil, 199-209.

Namba R; Higa SY, 1973. Papaya mosaic virus transmission as affected by the duration of the preliminary fasting and virus acquisition feeding of Myzus persicae. Proceedings of the Hawaiian Entomological Society, 22(1):113-117

Namba R; Higa SY, 1975. Retention of the inoculativity of the papaya mosaic virus by the green peach aphid. Proceedings of the Hawaiian Entomological Society, 22(3):491-494

Namba R; Higa SY, 1978. Papaya mosaic transmission as affected by the duration of the acquisition probe of the green peach aphid - Myzus persicae (Sulzer). Proceedings of the Hawaiian Entomological Society, 23(3):431-433

Namba R; Kawanishi CY, 1966. Transmission of papaya mosaic virus by the green peach aphid. Journal of Economic Entomology, 59:669-671.

Noshad QQ; Zafar Y; Khan MA; Neelam Rashid; Nafeesa Zahid; Tanveer Bashir; Zahid Ali; Saadia Naseem, 2015. First record of Papaya ring spot virus (PRSV) strain in Malir District Sindh and in Islamabad Pakistan. International Journal of Agriculture and Biology, 17(2):399-402. http://www.fspublishers.org/published_papers/21841_..pdf

Oliveira FC; Madeira MCB; Pinheiro CSR; Kitajima EW; Padovan I, 1992. OcorrOncia e estudos ultramicroscópicos do vfrus do mosaico do mamoeiro ("Papaya ringspot virus") no estado do Rio Grande do Norte. Fitopatologia Brasileira, 17:195.

Omar AF; El-Kewey SA; Sidaros SA; Shimaa AK, 2011. Egyptian isolates of Papaya ringspot virus form a molecularly distinct clade. Journal of Plant Pathology, 93(3):569-576. http://sipav.org/main/jpp/index.php/jpp/article/view/1224

Opina OS, 1986. Studies on a new virus disease of papaya in the Philippines. Plant virus diseases of horticultural crops in the tropics and subtropics Taipei, Taiwan; Food and Fertilizer Technology Centre for the Asian and Pacific Region, 157-168

Paguio OR; Barbosa FR, 1979. Constatanao do "papaya ringspot virus" no Estado de Pernambuco. Fitopatologia Brasileira, 4:133.

Papayiannis LC; Ioannou N; Boubourakas IN; Dovas CI; Katis NI; Falk BW, 2005. Incidence of viruses infecting cucurbits in Cyprus. Journal of Phytopathology, 153(9):530-535. http://www.blackwell-synergy.com/servlet/useragent?func=showIssues&code=jph

Parris GK, 1938. A new disease of papaya in Hawaii. Proceedings of the American Society for Horticultural Science, 36:263-265.

Parris GK, 1941. Disease of papaya in Hawaii and their control. In: Papaya production in the Hawaiian Islands. Hawaii Experiment Station Bulletin 87, 32-44.

Perera WGS; Suetsugu T; Saito N, 1998. Occurrence of papaya ring spot potyvirus strain P in Sri Lanka. JICA/NPQS Occasional Paper, No. 1:14 pp.; 5 ref.

Pinese B; Lisle AT; Ramsey MD; Halfpapp KH; Faveri Sde, 1994. Control of aphid-borne papaya ringspot potyvirus in zucchini marrow (Cucurbita pepo) with reflective mulches and mineral oil-insecticide sprays. International Journal of Pest Management, 40(1):81-87

Pinto OL, 1972. Identification de las virosis de la lechosa (Carica papaya L.) en Venezuela. Revista de la Facultad de Agronomia, 6:5-36.

Pourrahim R; Farzadfar S; Golnaraghi AR; Shahraeen N, 2003. First report of Papaya ringspot virus on papaya in Iran. Plant Disease, 87(9):1148.

Prasad SM; Sarkar DP, 1989. Some ecological studies on papaya ringspot virus in Ranchi. Indian Journal of Virology, 5(1-2):118-122

Provvidenti R, 1996. A Taiwan strain of papaya ringspot virus from Carica papaya causing prominent symptoms on cultivated cucurbits. Report - Cucurbit Genetics Cooperative, No. 19:83-84; 9 ref.

Provvidenti R; Gonsalves D, 1982. Resistance to papaya ringspot virus in Cucumis metuliferus and its relationship to resistance to watermelon mosaic virus 1. Journal of Heredity, 73(3):239-240

Purcifull DE; Hiebert E, 1979. Serological distinction of watermelon mosaic virus isolates. Phytopathology, 69(2):112-116

Purcifull DF; Edwardson JR; Hiebert E; Gonsalves D, 1984. Papaya ringspot virus. CMI/AAB. Description of Plant Viruses, No. 292, Wellesbourne, UK: Association of Applied Biologists.

Quemada H; L'Hostis B; Gonsalves D; Reardon IM; Heinrikson R; Hiebert EL; Sieu LC; Slightom JL, 1990. The nucleotide sequences of the 3-terminal regions of papaya ringspot virus strains W and P. Journal of General Virology, 71(1):203-210

Raj Verma; Ram RD; Tomer SPS, 2007. Survey and surveillance of Papaya ring spot virus disease in India. Journal of Maharashtra Agricultural Universities, 32(2):277-278.

Ray PK; Yadav JP; Kumar A, 1999. Effect of transplanting dates and mineral nutrition on yield and susceptibility of papaya to ringspot virus. Horticultural Journal, 12(2):15-26; 12 ref.

Rezende JAM, 1984. Mosaico ou mancha anular do mamoeiro: qual a melhor designatao no Brasil? Fitopatologia Brasileira, 9:455-565.

Rezende JAM, 1985. Tentativas de premunizanao para o controle do mosaico do mamoeiro. MS Thesis. Piracicaba, Brazil, Universidade de Sao Paulo.

Rezende JAM; Costa AS, 1984. Disseminatao do vfrus do mosaico do mamoeiro em duas regioes do Estado de Sao Paulo. Fitopatologia Brasileira, 9:407.

Rezende JAM; Costa AS, 1985. Produtao de lesoes locais em Chenopodium quinoa pelo potyvirus causador do mosaico do mamoeiro no Brasil depende da origem das sementes. Summa Phytopathologica, 11:39-42.

Rezende JAM; Costa AS, 1986. Viroses do mamoeiro. Informe Agropecuário (Brazil), 12:44-48.

Rezende JAM; Costa AS, 1987. Symptom intensification makes it difficult to control pawpaw ringspot by pre-immunization. Fitopatologia Brasileira, 12(1):100-101

Rezende JAM; Costa AS, 1993. Papaya diseases caused by viruses and mycoplasmas. Summa Phytopathologica, 19(2):73-79

Rezende JAM; Costa AS; Martins ALM; Tulman Neto A; Soares NB, 1985. Segreganao de tolerância ao vfrus do mosaico do mamoeiro na variedade IAC-98 observada em ensaio de progOnies. Summa Phytopathologica, 11:42-45.

Rezende JAM; Costa AS; Soares NB; De Negri JD, 1987. Plantios-piloto de mamoeiros em Registro completam um ano sem incidOncia de mosaico. Summa Phytopathologica, 13:27.

Rezende JAM; Costa AS; Yuki VA, 1986. Menor disseminatao do vfrus do mosaico do mamoeiro em Pariquera-Anu oferece possibilidade para a produnao de mamao em Sao Paulo. Summa Phytopathologica, 12:11.

Rezende JAM; Costa ßS, 1995. Alternatives for integrated control of papaya ringspot. Acta Horticulturae, No. 370:129-132; 28 ref.

Rezende JAM; Mnller GW, 1995. Mecanismos de protetao entre vfrus e controle de viroses de vegetais por premunizanao. Revisao Anual de Patologia de Plantas, 3:185-226.

Rivas Platero GG; Larios JF, 1994. Epidemiology of papaya ringspot virus (PRSV) in Zapotitan, El Salvador. Manejo Integrado de Plagas, No. 32:5-7

Rivera C; Villalobos W; Sanchez MV; Zumbado C; Rodriguez CM, 1993. Identification and distribution of melon-infecting viruses and their vectors in two provinces of Costa Rica. Turrialba, 43(3):210-215

Rodríguez-Martínez D; Figueira Ados R; Duarte Pde SG; Galvino-Costa SBF; Olmedo JG, 2015. First report and molecular characterization of an isolate of Papaya ringspot virus (PRSV-W) detected in pumpkin in Cuba. Bioscience Journal, 31(4):1133-1142. http://www.seer.ufu.br/index.php/biosciencejournal/article/view/26181/16734

Sajid Husain, 1997. Detection of papaya ringspot virus from rings of unripe papaya fruit by penicillinase enzyme based ELISA. Indian Journal of Virology, 13(1):41-42; 6 ref.

Sheen TF; Wang HL; Wang DN, 1998. Control of papaya ringspot virus by cross protection and cultivation techniques. Journal of the Japanese Society for Horticultural Science, 67(6):1232-1235; 11 ref.

Shrestha SK; Albrechtsen SE, 1992. Outbreaks and new records. Nepal. Identification of new virus diseases in Nepal. FAO Plant Protection Bulletin, 40(4):167-170

Somowiyarjo S, 1993. Detection and identification of cucurbit viruses in Yogyakarta. Ilmu Pertanian, 5(3):657-663; 16 ref.

Souza Jr. MT, 1999. Analysis of the resistance in genetically engineered papaya against papaya ringspot potyvirus, partial characterization of the PRSV, Brazil, Bahia isolates, and development of transgenic papaya for Brazil. (Ph.D. Dissertation). Ithaca. Cornell University. USA.

Souza Jr. MT, 2000. Transgenic papaya (Carica papaya L.) expressing the coat protein (CP) gene of papaya ringspot virus (PRSV) and with broad spectrum of resistance to Brazilian isolates of the virus. Virus Reviews and Research 5(2):22-25.

Souza Jr. MT, Gonsalves, D, 1998. Development of trangenic Carica papaya L. resistant to the Brazilian isolate of PRSV: a case of technology transfer between Cornell University and EMBRAPA. Phytopathology 88:S137.

Souza Jr. MT, Gonsalves, D, 1999. Genetic engineering resistance to plant virus diseases, an effort to control papaya ringspot virus in Brazil. Fitopatologia Brasileira 24(4):485-502.

Souza Jr. MT, Tennant P, Gonsalves, D, 1998. Number of coat protein (cp) inserts, gene dosage , and cp sequence affect resistance of transgenic papaya to papaya ringspot virus (PRSV). Phytopathology 88:S84.

SPC-PPS, 2003. Papaya ringspot disease confirmed in French Polynesia. Pest Alert No. 32. Suva, Fiji Islands: Plant Protection Service Secretariat of the Pacific Community.

Sßnchez de Luque C; L=pez GM, 1976. Reconocimiento del virus de la mancha anular de la papaya (Carica papaya L.) en Colombia. Revista do Instituto Colombiano Agropecu rio, 11:205-220.

Sßnchez de Luque C; L=pez GM, 1977. Identificacion de plantas hospedantes del virus de la mancha anular de la papaya. Fitopatologia Colombiana, 6:112-121.

Story GE; Halliwell RS, 1969. Identification of distortion ringspot virus disease of papaya in the Dominican Republic. Plant Disease Reporter, 53:757-760.

Story GE; Walliwell RS; Smith LR, 1968. Investigacion de los virus de papaya (Carica papaya L.) en la Republic Dominicana, con apuntes especiales sobre la associacion de un organismo del tipo mycoplasma con la enfermedad "bunchy top", Division de Investigaciones Agricolas, Instituto Superior de Agricultura. Boletim No. 14.

Sureka SK; Mathur K; Shukla DD, 1977. Virus diseases of papaya (Carica papaya) in Udaipur. Indian Journal of Mycology and Plant Pathology, 7(2):115-121

Taya RS; Singh JP, 1997. Studies on the transmission of papays ring spot virus by Aphis craccivora Koch. Indian Journal of Agricultural Research 31(4):237-240.

Teliz D; Mora G; Nieto D; Gonsalves D; Garcia E; Matheis L; Avila C, 1991. Papaya ringspot virus in Mexico. Revista Mexicana de Fitopatologia, 9(1):64-68

Tennant PF; Fitch MMM; Manshardt R; Slightom JL; Gonsalves D, 1997. Resistant against papaya ringspot virus isolates in coat protein trangenic papaya is affected by transgene dosage and plant development. Phytopathology 87:S96.

Tennant PF; Gonsalves C; Ling KS; Fitch M; Manshardt R; Slightom JL; Gonsalves D, 1994. Differential protection against papaya ringspot virus isolates in coat protein gene transgenic papaya and classically cross-protected papaya. Phytopathology, 84(11):1359-1366

Thomas JE; Dodman RL, 1993. The first record of papaya ringspot virus-type P from Australia. Australasian Plant Pathology, 22(1):2-7

Torres MR; Giacometti DC, 1966. Virosis de la papaya (Carica papaya L.) en el valle del Cauca. Agricultura Tropical (Colombia), 22:27-38.

Tripathi S; Suzuki JY; Ferreira SA; Gonsalves D, 2008. Papaya ringspot virus-P: characteristics, pathogenicity, sequence variability and control. Molecular Plant Pathology, 9(3):269-280. http://www.blackwell-synergy.com/doi/full/10.1111/j.1364-3703.2008.00467.x

Trujillo Pinto G; Vegas A; Monteverde E, 1989. Control of the distortion ringspot virus (DRSV) in papaya by spraying with white oil. Revista de la Facultad de Agronomia, Universidad Central de Venezuela, 15(1-2):141-155

Tsai CT, 1998. EM application protected papaya culture. Journal of the Chinese Society for Horticultural Science 44(1):93-101.

Van Regenmortel MHV, 1971. Watermelon mosaic virus. CMI/AAB. Description of Plant Viruses No. 63. Wellesbourne, UK: Association of Applied Biologists, 4 pp.

Vega J; Robbs CF, 1988. Detectao do vfrus do mosaico em mamoeiros do Rio Grande do Sul através de microscopia electrônica. Summa Phytopathologica, 14:32.

Verma R; Gaikwad P; Mungekar D; Tripathi S; Datar V; Singh J, 2014. First report of mixed infection of Papaya ringspot virus and phytoplasma in papaya in India. Journal of Plant Pathology, 96(2):438. http://www.sipav.org/main/jpp/

Videla REP, 1953. Las virosis de la lechoza (Carica papaya L.) en Venezuela. I. Transmission del "mosaico". Agronomia Tropical (Venezuela), 2:241-251.

Vucurovic A; Bulajic A; Ðekic I; Ristic D; Berenji J; Krstic B, 2009. Presence and distribution of oilseed pumpkin viruses and molecular detection of Zucchini yellow mosaic virus. (Prisustvo i rasprostranjenost virusa uljane tikve i molekularna detekcija virusa zutog mozaika cukinija.) Pesticidi i Fitomedicina, 24(2):85-94.

Wahab N, 1991. Papaya ringspot virus disease (PRV) is here in Malaysia. MAPPS Newsletter, 15(3):36

Wang CH; Yeh SD, 1992. Nucleotide sequence comparison of the 3-terminal regions of severe, mild, and non-papaya infecting strains of papaya ringspot virus. Archives of Virology, 127(1-4):345-354

Wang CH; Yeh SD, 1997. Divergence and conservation of the genomic RNAs of Taiwan and Hawaii strains of papaya ringspot potyvirus. Archives of Virology, 142(2):271-285; 59 ref.

Wang DN, 1982. Screen of papaya varieties for ringspot virus tolerance. Journal of Agricultural Research of China, 31:162168

Wang HL; Wang CC; Chiu RJ; Sun MH, 1978. A preliminary study of papaya ringspot virus in Taiwan. Plant Protection Bulletin, 20(2):133-140

Wang HL; Yeh SD; Chiu RJ; Gonsalves D, 1987. Effectiveness of cross-protection by mild mutants of papaya ringspot virus for control of ringspot disease of papaya in Taiwan. Plant Disease, 71(6):491-497

Wang JJ; Yeh SD; Wang JJ; Yeh SD, 1998. Characterization of the papaya ringspot virus W type isolates collected from different areas of Taiwan by host reactions, immunodiffusion tests and TR-PCR. Plant Protection Bulletin Taipei 40(4):383-395.

Wolfenbarger DO, 1966. Incidence-distance and incidence-time relationships of papaya virus infections. Plant Disease Reporter, 50:908-909.

Xiao HuoGen; Tetsuo MaoKa; Luo XueHai, 1997. Investigation and identification of papaya ringspot virus and papaya leaf - distortion mosaic virus in South China. Journal of South China Agricultural University, 18(4):52-53 (Ch), 58 (En); 5 ref.

Xiao-HG; Fan-Huai Zhong; Xiao-HG; Fan HZ, 1994. Studies on the cross-protection among strains of papaya ringspot virus. Chinese Journal of Virology, 10:164-171.

Yeh SD; Cheng YH; Bau HJ; Yu TA; Yang JS, 1997. Coat-protein transgenic papaya immune or highly resistant to different strains of papaya ringspot virus. Phytopathology 87:S107.

Yeh SD; Gonsalves D, 1984. Evaluation of induced mutants of papaya ringspot virus for control by cross protection. Phytopathology, 74(9):1086-1091

Yeh SD; Gonsalves D, 1994. Practices and perspective of control of papaya ringspot virus by cross protection. Advances in Disease Vector Research, 10:237-257

Yeh SD; Gonsalves D; Provvidenti R, 1984. Comparative studies on host range and serology of papaya ringspot virus and watermelon mosaic virus 1. Phytopathology, 74(9):1081-1085

Yeh SD; Gonsalves D; Wang HL; Namba R; Chiu RJ, 1988. Control of papaya ringspot virus by cross protection. Plant Disease, 72(5):375-380

Yeh SD; Jan FJ; Chiang CH; Doong TJ; Chen MC; Chung PH; Bau HJ, 1992. Complete nucleotide sequence and genetic organization of papaya ringspot virus RNA. Journal of General Virology, 73(10):2531-2541

Yuki VA; Costa AS; Souza-Dias JAC de; Rezende JAM, 1987. Baixa populatao alada, em revoadas, de affdeos vetores de fitovfrus em Pariquera-Atu. XI Congresso Brasileiro de Entomologia. Campinas, Brazil. Volume 1, 144.

Zettler FW; Edwardson JR; Purcifull DE, 1968. Ultramicroscopic differences in inclusions of papaya mosaic virus and papaya ringspot virus correlated with differential aphid transmission. Phytopathology, 58:332-335.

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