Isolation and phylogenetic analysis of the jimsonweed isolate of Turnip curly top virus

Turnip curly top virus (TCTV) is a type member of the genus Turncurtovirus previously reported from Iran. TCTV has a wide host range among vegetables and weeds. In this study, the TCTV infection of the symptomatic jimsonweed (Datura stramonium L.) showing general yellowing, severe curling and cup-shaped leaves was confirmed by PCR. Full-length genome of this isolate was amplified using combination of the PCR and rolling circle amplification (RCA) and cloned into the pJET1.2 vector. Resulted nucleotide sequence indicated that the jimsonweed isolate of TCTV shares maximum and minimum identities (85.8-99.2%) with turnip and radish isolates of TCTV, respectively. In spite of high similarity between full-length nucleotide sequence of jimsonweed and several GenBank isolates, predicted rep protein of the jimsonweed isolate has an additional 14 amino acid residues at the N-terminal. Among five TCTV strains, the jimsonweed isolate was classified in the strain C with turnip and leafhopper isolates of the virus. Results of this study again confirm wide host range of turncurtoviruses in weeds and the role of wild species in infection of vegetables.