VIEW ARTICLE

Properties of a Strain of Tobacco Mosaic Virus Isolated from White Ash Trees. Allan O. Lana, Research Assistant, Department of Plant Pathology, University of Massachusetts, Amherst, 01002, Present address of senior author: Department of Agricultural Biology, University of Ibadan, Ibadan, Nigeria; George N. Agrios, Associate Professor, Department of Plant Pathology, University of Massachusetts, Amherst, 01002. Phytopathology 64:1490-1495. Accepted for publication 14 June 1974. DOI: 10.1094/Phyto-64-1490.

The properties and identity of a virus isolated from leaves of white ash trees showing chlorotic ring spots and line pattern foliar symptoms have been determined. This virus has a dilution end point of 10^–6 - 10^–7 and a thermal death point of 97 C in crude sap of infected Chenopodium and tobacco leaves, and produced symptoms on 26 out of 45 hosts tested. Electron microscopy of clarified sap of naturally infected ash leaves, and of purified virus preparation from inoculated tobacco, revealed that the virus particles were rodshaped and similar in size to those of tobacco mosaic virus (TMV). On sucrose density-gradient, the purified virus separated into one band which upon UV-monitoring gave a single infectious peak. Antiserum to the ash virus was produced which reacted positively with its homologous antigen and with two strains of TMV with a titer of 1:4,096.