Comparative studies on tomato aspermy and cucumber mosaic viruses: III. Further studies on relationship and construction of a virus from parts of the two viral genomes

Abstract

Although the V strain of tomato aspermy virus (TAV) and the Q strain of cucumber mosaic virus (CMV) do not show any detectable serological relationship or nucleotide base sequence homology, it was possible to construct a pseudo-recombinant virus from parts of their RNA genomes. The pseudo-recombinant from the two largest RNA molecules of TAV (T 1 and T 2) when combined with the third largest molecule of CMV (C 3) formed a stable virus whose coat protein was like that of CMV, but it induced symptoms on several plants indistinguishable from those produced by TAV. It is concluded that TAV and CMV have functionally divided genomes and that the coat protein cistron is located on RNA component 3, whereas the cistron or cistrons determining host reactions are located on either RNA component 1 or 2, or on both 1 and 2.