RELATIONSHIPS AMONG VIRUSES IN THE TOMBUSVIRUS GROUP - NUCLEIC-ACID HYBRIDIZATION STUDIES

RNAs of definitive tombusviruses are about 4700 nucleotides in length; those of tentative members of the tombusvirus group, turnip crinkle virus (TCV) and glycine mottle virus (GMeV) are about 3900 nucleotides and those of saguaro cactus virus (SCV) and galinsoga mosaic virus (GMV) are about 3500 nucleotides. Hybridization with cDNA showed that there is some homology between the nucleic acids of different definitive tombusviruses. Analysis of the melting behaviour of heterologous cDNA:RNA hybrids suggests that different parts of the genome may be involved in hybrids between different combinations of tombusviruses. There is no homology between the nucleic acids of definitive tombusviruses and those of GMV, GMeV, SCV or TCV