Figure 3.

Phylogenetic tree of the nucleotide sequences of PEDV samples based on the ORF3 gene. Sequences of reference strains were obtained from the GeneBank database. GeneBank accession numbers were shown in Table 1. Tree topology was constructed using F84 model and bootstrap re-sampling (1,000 data sets) of the multiple alignments was used to test the statistical robustness of the trees obtained by NJ (using the program Neighbor from Mega v4.0 package) G1-G4: Divided groups by phylogenetic tree. The underlines represent the Fujian field samples in this study.