Complete genome sequence analysis of two Citrus tatter leaf virus (CTLV) isolates from China

In order to understand molecular characterization of Citrus tatter leaf virus (CTLV) isolated from China, full-length cDNAs of CTLV-MTH and CTLV-XHC from Citrus reticulata and Citrus sinensis were cloned and sequenced based on whole-genome amplification by RT-PCR. The complete nucleotide sequences of CTLV-MTH and CTLV-XHC were determined to be 6 497 nucleotides in length and shared 79.9–91.0% and 78.8–98.0% nucleotide sequence identity, respectively, with other Apple stem grooving virus (ASGV) or CTLV strains available in GenBank. Unexpectedly, CTLV-MTH showed the highest nucleotide sequence identity (91%) with an apple isolate of ASGV, followed by 86.5% with ASGV-HH and 85.7% with ASGV-CHN. Furthermore, CTLV-MTH and three ASGV strains were grouped to a separate cluster in the phylogenetic tree, suggesting it has a closer relationship to ASGV than to CTLV. Therefore, it can be concluded roughly that CTLV may be not a distinct strains of ASGV. We proposed that Citrus tatter leaf virus should be renamed Apple stem grooving virus.