Maize stripe virus: characteristics of a member of a new virus class.

An unusual filamentous nucleoprotein about 3 nm in diameter was consistently associated with maize stripe-diseased maize. Antiserum to purified nucleoprotein neutralized the infectivity of extracts from maize stripe-diseased plants suggesting that the nucleoprotein was the maize stripe virus (MStpV). The rate-zonal sedimentation pattern of the nucleoprotein on sucrose gradients was polydisperse between 51 and 70 S. CsCl isopycnic centrifugation of combined nucleoprotein zones from sucrose gradients resulted in a single band of 1.28 g/ml. The nucleoprotein consisted of 5.2% RNA and a single capsid protein of molecular weight 32,700 daltons. Large quantities of a noncapsid protein of molecular weight 16,300 daltons were also found in MStpV-infected tissue. MStpV was transovarially transmitted by its vector, Peregrinus maidis. Other species susceptible to MStpV in addition to Zea mays were Rottboellia exaltata and Sorghum bicolor. The similarities between MStpV and rice stripe virus are discussed. We conclude that these viruses represent a new virus class.