The characterization of a virus responsible for peach rosette mosaic and grape decline in Michigan

摘要

Virus isolates obtained from peach with rosette mosaic and from grapes with lsquo;declinersquo; in Michigan have a similar host range and in vitro properties and morphology and are related serologically. Particles are isometrics averaging 28ensp;nm in diameter. Isolates of virus from both sources, where transmitted manually, induced rosette mosaic on peach and decline on grapes.The virus is seed-borne inChenopodium quinoaWilld., but it is not transmitted byCuscuta campestrisL. or byMyzus persicaeSulz. Partially purified virus preparations contain two infectious and serologically active components with sedimentation coefficients (s20,w) of 115 and 134, with molecular weight of 5.5 and 6.3 daltons, and with estimated values of 37 and 44 ribonucleic acid (RNA), respectively. The UV absorption at 254ensp;nm of the middle and bottom infectious components is not dependent on the time after inoculation ofC. quinoa, suggesting that the slowest component is not a precursor of the virus. Both components were reproduced when each was inoculated separately intoC. quinoa. Virus isolates recovered from infected grapes varied in virulence, and serological differences could be detected by cross absorption and immunodiffusion tests. The name peach rosette mosaic virus (PRMV) is proposed for the virus responsible for the grape decline. The cryptogram of the virus is(R)/*;*/*;S/S;S/Ne.