The global distribution of reveals little evidence for frequent recent, human-mediated long distance dispersal events.

(BBTV; family Nanoviridae, genus ) is a multi-component single-stranded DNA virus, which infects banana plants in many regions of the world, often resulting in large-scale crop losses. We analyzed 171 banana leaf samples from fourteen countries and recovered, cloned, and sequenced 855 complete BBTV components including ninety-four full genomes. Importantly, full genomes were determined from eight countries, where previously no full genomes were available (Samoa, Burundi, Republic of Congo, Democratic Republic of Congo, Egypt, Indonesia, the Philippines, and the USA [HI]).

Evidence of inter-component recombination, intra-component recombination and reassortment in banana bunchy top virus.

Banana bunchy top virus (BBTV; family Nanoviridae, genus Babuvirus) is a multi-component, ssDNA virus, which causes widespread banana crop losses throughout tropical Africa and Australasia. We determined the full genome sequences of 12 BBTV isolates from the Kingdom of Tonga and analysed these together with previously determined BBTV sequences to show that reassortment and both inter- and intra-component recombination have all been relatively frequent occurrences during BBTV evolution. We found that whereas DNA-U3 components display evidence of complex inter- and intra-component recombination, all of the South Pacific DNA-R components have a common intra-component recombinant origin spanning the replication-associated protein gene.