Analysis of the sequence of Dioscorea alata bacilliform virus; Comparison to other members of the badnavirus group

The complete nucleotide sequence of the genome of Dioscorea alata bacillifo rm virus (DaBV) has been determined from cloned fragments. Features of the genome confirm DaBV to be a pararetrovirus of the genus Badnavirus which is more similar to other mealy-bug transmitted badnaviruses, in particular to cacao swollen shoot virus, than to rice tungro bacilliform virus. Sequence variability between cloned fragments suggests that the genetic variability of the virus may be quite high (up to 11% nucleotide sequence variation fo r some small regions of the genome) although the overall variability detect ed was 4.2% at the nucleotide level.