Bioassay and phylogeny of five Iranian isolates of Cucumber mosaic virus from different hosts based on CP gene sequence

Using double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA), Cucumber mosaic virus (CMV) was detected in 31 out of 132 symptomatic leaf samples collected from different hosts of Urmia province of Iran, during 2011-2012. In biological assays, five different host isolates caused severe mosaic in Nicotiana species and Capsicum annum without significant difference in severity. Based on phylogenetic analysis of coat protein nucleotide and deduced amino acid sequence, two isolates were clustered into subgroup IA, while other three isolates were grouped into IB subgroup of CMV. All Urmian isolates shared a common MspI, and no EcoRI and BsuRI restriction sites. In contrast to S-IA isolates, the second MspI site was found at 473-476 position of only S-IB isolates, which could be used to differentiate two S-IA and S-IB subgroups. Here, we report the first case of Abutilon theophrasti infection, as a new reservoir weed host for CMV in the world.