Abstract
Aphid transmissible Japanese isolate of caulifiower mosaic virus M (CaMV-M) was cloned into pUC19 and its ORF II region was sequenced. Comparison of this sequence with that of CM1841 (non-aphid transmissible isolate of CaMV) showed that there were nine base changes, four of which gave rise to alterations in the predicted amino acid sequence. Characterization of in vitro recombined hybrid viruses between CaMV-M and CM1841 showed that 5' half of ORF II was responsible for the lack of aphid transmissibility in CM1841 and this region influenced the amount of accumulation of ORF II product in the infected leaves.
