Cloning and sequencing of banana bunchy top virus genome component I.
A fragment of Banana bunchy top virus (BBTV) component Ⅰ (about 500bp) was amplified by PCR using total DNA from infected banana tissues as template and oligonuleotides designed from the published component Ⅰ sequence as primers. Sequence analysis showed that it was about half region of BBTV component Ⅰ. With an adjacent pair of primers designed based on the sequenced half of component Ⅰ and the same template as the above, a 1,104kb fragment was produced by PCR. The sequence analysis indicated that this fragment is full-length component Ⅰ of BBTV. Sequence comparison revealed that the component Ⅰ of Zhangzhou isolate shared homologies of 89.0% and 96% with those of the Australian and Chinese Taiwan isolates, respectively.