Genome analysis of a severe and a mild isolate of Papaya ringspot virus-type W found in Brazil.

Papaya ringspot virus-type W (PRSV-W) is one of the most economically threatening viruses of cucurbits in Brazil. Premunization is one of the most effective PRSV control measures currently applied in squash and zucchini crops. PRSV-W-1, a mild and premunizing strain of PRSV has been successfully used to protect cucurbits against both the severe PRSV-W-C strain and other Brazilian PRSVs.