Figure 3
From: The spike glycoprotein genes of porcine epidemic diarrhea viruses isolated in China
The phylogenetic trees based on the full-length or indicated fragments of PEDV S genes that have been analyzed in Figure 1. The blue squares indicate the virulent strains isolated outside of China. The red triangles indicate the cell culture-adapted vaccine strains or the pandemic strains used to make vaccines. The green upside-down triangles indicate the GI-c viral isolates.