Trabalho apresentado no 10º National Meeting of Virology, 2º Mercusul Meeting of Virology, Curitiba, 1999

OLIVEIRA, E.

SCHONS, J.

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RT-ll: CURRENT VESICULAR DISEASES IN LATIN AMER}CA VETERlNARY MEDIClNEl. VESICULAR STOMATITISAlcjandro LopesCcmro Panarnericano de Febre Aftosa. RJ2. THE DlFFERENTIAL DIAGNOSIS OF VESICULAR DISEASESJorge W. LópezFoot and Mouth Dlsease Center, Rio de Janeiro. BrasilThere are four vesicular diseases of domesuclivestock: Foot and MOUlh Disease (FMD). VesicularStomatitis, Swine Vesicuíar Disease and Vesicular Examhemaof Swine. The typical lesion is a vesic\e and laboratoryassistance is required for a differenúal diagnosis.ln addition there are hemorrhagic diseases with mucosalerosions like in Bluetongue. Akabane. EpizooricHemorrhagic Oisease of Deer and Ibarak.i. Also there arediseases of the respiratory tract that can produce lesions inthe mucos as as in Malignanl Catharral Fever and IBR.Ulcerative gastroenteritis can also produce lesions in themucosal surfaces as in BVO. Rinderpest, Peste de PeruRuminunts, Jembrana Oisease and mycotoxicoses. Finallythere are non-vesicular diseases with primary lesion in lheskin as the poxviruses infections. Herpes Marnillitis.Sweating Sickness and fungal toxins (Bocopa). Some ofthese diseases are exotic 10 South Ameriea.With the new epidemiological situarion of FMO in lhecominent and the perspecuve of disease eradication, everyoutbreak showing sick animais with lesions cornpatible witha vesicular condition must be carefully studied and a finaldiagnosis reponed promptly so lhe strict sanitary measurescan be lifted.There are direct and indirect tests. With lhe direct tests lheviral panieles or their components as nuc1eie acids andproteins can be detected in the sample. These tests inc1udevirus isolation, electron microscopy. ELISA. eomplementfixauon. irnmunohistoquirnica, in si tu hybridization and PCR.The indirecr tests detect the immune response of the hOSIagainst the vira! infection. Some ofthese rnethods are AGID.virus neutralization, ELISAs. hernoagglutinauon and EITB.The final diagnosis should be obtained with lhe use of lhecornbination of direct and indirect tests that better fit lheparticular needs and conditions of lhe laboratory.3. OFFIClAL DlAGNOSTIC USED IN LEGAL LA80RATORIES TO VESICULAR DISEASESCid de AlcncarLAPA.PERT-12: VIRUSESCONTROL BREAKTHROUGH IN TROPICAL FRUlTS AND GRAMINEOUS1. GRAMINAE'S VIROSIS IN BRAZILE.Oliveira'; lSchons1'Embrapa Milho e Sorgo - CP 151.35701-970. Sete Lagoas MG. Brazil.bethrêcnpms.embrapa.br, ~UPF - CP 611.9900 1-970. Passo Fundo. RSMore than 40 viruses infect economical crops, pastures andweeds in Graminae family (Poaceae). Many of them arerestricted 10 this family.ln Brazillhe most importam Poaceaespecies that can be affected by virosis are: Maize (12millionsha); sugarcane (5 millions na); rice (3,2 millions ha); wheat(1.3 millions ha); sorghum (300 lhousand haja barley. oat,and pastures. lnfonnation about virosis in these species arescarcc. The viruses identified are: maize dwarf mosaic (poryj;maize mosaic (nucleorhabdo); maize rayado fino (marafl);maize rough dwarf (fiji gr. 2); sugarcane mosaic (potyj;sugarcane bacillifonn (badna); barley yellow dwarf (luteo);wheat spindle streak mosaie (byrno): soil bome wheat mosaic(furo). brome mosaic (bramo). The potyvlrus-indaced-mosaic reduces maize plams production around 50'1. Theseviroses are transmined by aphids and can infect many Poaceaespecies. Their erop outbreaks can be up 10 100% of incidence.They are largely disseminated in agricultural areas, Nucleicacid and aminoacids studies from maize potyvirus showedsimilarities of81.8 and 89.2% with SCMV-SC and 86.3 and87,4% with MDMV-B. respectively. The majority of rnaizecultivars are susceptible to these viruses however, resistancesources are available. The peroxidase activity increased inmaize plants infected by these viruses. It was possible.without infection, 10 discriminare 82% of suscepribleinbredlines by the low levels of peroxidase acuvity, Thernaize rough dwarf vírus was detected in Foz do Iguaçú andCascavel in 1986. This needs confirmation and evaluauonincidence in maize and wheat. Some years ago lhe poryvirus-34mduced-mosaic was very imponanl in sugarcane and wascornrolled by geneuc resistance. Nowadays il is again aproblem to sugarcane, sorghum and maize. Among 5serorypes of barley yellow dwarf. lhe mosi common in whe:nare: BYDV-pav (transrniued by Rhopalosiphum padi)2. PAPAYA RINGSPOT VIRUSPaulo Emesto Meissner FilhoEmbrapa Cassava and Tropical FruitsIn Brazil, lhe disease k.nown as papaya mosaic iscaused by lhe papaya ringspot vírus (PRSV). which producedchlorosis of upper leaves, oily streaks on lhe stem, rings inlhe Iruits, mosaico leaf deformation and stunting of lhe planLThe virus belongs to lhe family Potyviridae, genus Potyvirus,ha..•ficxuous panicles. ssRNA positive sense. The virus RNApossesses only one open reading frame, which is translatedin a polyprotein U\llt is proteolytic processed in llDolherviralproreins. PRSV infects Chenopodiaceae, Caricaceae andCucurbitaceae and has two strains, strain "p" ínfects papayaand cueurbit and "w" infeets only cucurbit. The 3' terminalof PRSV -p and w has 98,2% in aminoacid homology in NIbgene and 97.7% homology at CP gene, this result confirmthat they are strains of the same virus. This virus isdisseminated by aphids in lhe field from papaya to papayafollowed by SYDV-mav and BYDV-sgv (both transmiuedby Silobion aveane). The soil bome whear mosaic virus.transmiued by polymixa graminis has high incidence inwheat. Until now. there are no virosis identified in lhebrazilian rice crop.and mechanically transmited in experimental conditions.PRSV-p causes reduction in degree Brix and yield loss of72%. The vírus is quickly disseminate and being able lO infectin less than scvcn months, an entirc orchard. For PRSVcomrol different strategies ean be used, as: a) roguing. b)using tolerante cultivars, like Cariflora, c) producingseedlings or growing papaya protected from vectors. d)growing around and ín lhe papaya fields com and Hibiscusspp .• e) using premunized plants and O producing papayatransgenics plants resistant to PRSV. 50 faro lhe tests withtransgenic papayas with CP gene showed that these plantsare resistam to some isolates ofPRSV. At the momento thereare several ways to control papaya ringspot and this usedepends on PRSV epidemiology in each region. econornicalviability of control and available technology.J. TROPICAL FRUIT VIRUSES 1N THE NORTHEAST OF BRAZILJ. Albersio A. LimaUniversidade Federa! do Ceará. Dept. de Fitotecnia.Laboratério de Virologia Vegetal, Cx. Postal 12.168 Fortaleza, CE60.356.000. e-mail:albersio@ufc.br. Fone: (-85) 227.0842The Northeast of Brazil has a great potential toproduce tropical fruits ali year around. inc\uding papaya,Carica papaya, passiontruit, Pssiflora edulis and banana.Musa spp. The passionfruit is a very importam fruit crop inthe Nonheast, but it has been iníected wilh lhe passion-Iruuwoodiness virus (PWV) which is· responsible for greatdamage in the crop production in several Brazilian States.The absence of satisfactory control measures and lhe lack ofsources of resistance for the vírus in lhe genus PassiJlorahave Stimulated lhe studies to isolare and develop mild strainsto be used in eross-protection programs. as a biologicalcontrol for lhe virus. A possible mild sttain of PWV wasisolated from passionfruit in Ibiapaba Mountain, Ceará.Severa! other viruses of minor imponance have also beendetected in passionfroit in Brazil. The cucumber mosaic vírus(CMV) ís one of the most cornrnon in lhe Nonheast and itean be found in mixed infection witb PWV. causing severesyrnptoms. The passionfruit veinelearing virus (PVCV)family Rhabdoviruiae was also found infecting passionfruitin lhe Nonheast, but its imponance in lhe Region needs tobe evaluated,Papaya is consumed ali over lhe world not only by itsnutritional values but also by its medicinal importance.Several íactors inhibit lhe expansion and productivity of thiscrop, and among them. lhe vírus diseases are considered ofgreat imponance. The papaya ringspot virus (PRSV-P) andpapaya lethal yellowing virus (PLYV) are lhe most imponantviruses in lhe Nonheast. The PRSV -P is considered a limitingfactor for papaya production in ali lhe countries where papayais cultivated, and it was detected in several Brazilian States.The vinis was found to reduce lhe number and weight offruits per plant by 22% and 60%, respectively. The PRSV-Phost range is restticted to Caricaceae and Cucurbitaceaespecies. The PLYV was first detected in lhe State ofPemambuco, but it was already identified in Sabia. RioGrande do Norte, Ceará and Paraíba. The syrnptorns causedby PLYV initiate as leaf yellowing on lhe superior part oflhe plant and with the disease evolution, lhe leaves becamedistoned and chlorotics. The fruits present circular greenspots lhat became yellowing wilh the time. The PLYV hostrange is, probably, restricted to lhe genus Carica. The viruswas purified and reeent results demonstrated that infectivevírus panicles ean be found in the soil, in green-houseirrigated water and in the seed surface from infected fruits.A new papaya disease named Stick C"Meleira") is probablyeaused by a virus and it represents a Iimiting factor for papayaproduction where it occurs.Although present in severa! banana plantations in Brazil. lhevírus diseases are not considered of great importance, as aconsequence of limited informations in the literature. The35 ,

Graminae's virosis in Brazil.

http://www.alice.cnptia.embrapa.br/alice/bitstream/doc/483552/1/Graminaesvirosis.pdf

Graminae's virosis in Brazil.

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