Abstract
Chrysanthemum plants infected with tomato aspermy virus (TAV) produce severely distorted and discoloured flowers but show only slight leaf mottle.TAV infected twenty‐five of forty‐five species (belonging to seventeen genera) tested and was transmitted by the aphid species Aulacorthum solarti, Macrosiphoniella sanborni and Myzus persicae.Sap from infected tobacco leaves lost infectivity when diluted more than 1 in 10,000, when heated for 10 min. at above 65°C. and when stored for more than 42 hr. at 16–18°C.Partial protection was obtained between TAV and two strains of cucumber mosaic virus. Evidence was obtained that this was true protection between related viruses and serological tests confirmed the view that TAV is a strain of cucumber mosaic virus. Evidence was obtained that this was true protection between related viruses and serological tests confirmed the view that TAV is a strain of cucumber mosaic virus.