Fig. 2.

Phylogenetic tree constructed with MEGA 4.1 illustrating the relationships among Bangladeshi IBDV isolates (GB1 and GB3) and 75 other strains of different geographical origins. Distance matrices were constructed using the Kimura's two-parameter model and trees were constructed using the neighbor-joining (NJ) algorithm based on the pairwise nucleotide differences in the VP2 variable region. Units at the bottom of the tree indicate the number of substitution events. The length of each pair of branches represents the distance between sequence pairs. The dataset was resampled 1,000 times using the bootstrap method. Accession numbers of the sequences and countries of origin are marked at end of strains when known.