Populus genotypes differ in infection by, and systemic spread of, Poplar mosaic virus

Abstract

The spatial and temporal dynamics of Poplar mosaic virus (PopMV) infection were investigated using four different genotypes of Populus. Four Populus clones were vegetatively propagated under sterile conditions and used as hosts for PopMV infection in controlled growth‐room experiments. The presence of PopMV RNA was assessed using reverse transcriptase PCR. The presence of infectious PopMV particles was assessed by the ability of extracts from Populus leaves to generate PopMV symptoms on the propagation host, Nicotiana megalosiphon. Neither PopMV RNA nor infectious particles accumulated to detectable levels in one of the four clones (CT6009), suggesting that this clone had preformed resistance to PopMV. PopMV RNA and infectious particles were restricted to the inoculated leaf in two of the clones (AP37 and NM6), suggesting that these clones restricted either the rate of virus accumulation or the spread of PopMV itself. In contrast, PopMV systemically infected one clone (52‐226), indicating that this host was either fully susceptible, or had delayed resistance.