Molecular Characterization of Tomato Leaf Curl Hainan Virus, a New Begomovirus, and Evidence for Recombination Z et al. Molecular Characterization of Tomato Leaf Curl Hainan Virus.

Virus isolates HaNHK7 and HaNHK8 were obtained from tomato plants showing leaf curl symptoms in Hainan Province of China. The complete DNA sequences of both isolates were determined to be 2748 nucleotides, with all the characteristic features of begomovirus genome organization. The two isolates share 99.8% identity with each other but have <88.3% nucleotide sequence identity with other begomoviruses. Consequently, HaNHK7 and HaNHK8 are considered to be isolates of a novel Begomovirus species, for which the name Tomato leaf curl Hainan virus (ToLCHnV) is proposed. ToLCHnV is most closely related to Papaya leaf curl China virus (PaLCuCNV, ) (88.3% in total nucleotide sequences). However, the AC2 gene more resembles that of Ageratum leaf curl virus (ALCuV, ) and AC1 and AC4 genes resemble those of Tomato leaf curl Vietnam virus (ToLCVV, ). Sequence analyses suggest that ToLCHnV may have arisen by recombination between viruses related to PaLCuCNV, ALCuV and ToLCVV. Neither the DNA-B component nor the DNA-β molecule was found to be associated with ToLCHnV isolates. [ABSTRACT FROM AUTHOR]