VIEW ARTICLE

Enhancement of the Infectivity, Nucleoprotein Concentration, and Multiplication Rate of Cowpea Chlorotic Mottle Virus in Manganese-Treated Cowpea. W. O. Dawson, Department of Plant Pathology and Plant Genetics, University of Georgia, Athens 30601, Present address: Department of Plant Pathology, University of California, Berkeley 94720; Phytopathology 62:1206-1209. Accepted for publication 1 May 1972. DOI: 10.1094/Phyto-62-1206.

The infectivity of cowpea chlorotic mottle virus was markedly enhanced in systemically infected cowpea leaves treated with toxic concentrations of manganese. The infectivity of sap from plants whose stems were maintained in 0.005 M MnSO₄ for 14 days beginning immediately after inoculation increased 2-fold. When treatment began 30 days after inoculation by maintenance of excised stems in 0.01 M MnSO₄, the sap infectivity increased 7-fold, the specific infectivity increased 8-fold, the virus nucleoprotein concentration increased 10-70%, and the rate of ³²P incorporation into virus particles increased 5- to 7-fold after 14 days of treatment.