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We determined the complete genome sequence of a lettuce chlorosis crinivirus (LCV) from China (LCV-NJ). The bipartite genome of LCV-NJ consists of RNA1 and RNA2 which are 8165 and 8454 nucleotides (nt) in length, respectively. The genomic structure of LCV-NJ RNA1 resembles that of LCV-California, an isolate with four open reading frames (ORFs) in RNA1. Although the amino acid sequences of ORF 1a and 1b have 92 and 99% identity between LCV-NJ and LCV-California, ORF 2 and ORF3 of LCV-NJ share only 63 and 71% identity with those of LCV-California, respectively. In addition LCV-NJ RNA2 contains 9 ORFs, compared to 10 ORFs in LCV-California. ORF10 was missing due to the deletion of a 173-nt sequence within the 3'-terminal region of LCV-NJ RNA2. Insertion or deletion of sequences of varying lengths was also observed in RNA1 and other regions of RNA2. Based on these findings, we propose that LCV-NJ/LCV-California may have undergone genome recombination and/or rearrangement in RNA1 and RNA2.

The complete genome sequence of a Capsicum chlorosis virus from China (CaCV-Hainan) was determined. The tripartite genome of CaCV-Hainan consists of small (S), medium (M), and large (L) RNAs of 3629, 4859, and 8912 nucleotides (nt), respectively. The S and M RNAs contain intergenic regions (IGRs) of 1348 and 462 nt, respectively. Strikingly, sequence comparisons among CaCV isolates revealed that the S RNA IGR of CaCV-Hainan derived from the CaCV-Qld-3432 Australia isolate through deletion of two stretches of 25- and 325-nt sequences within the S RNA IGR of CaCV-Qld-3432. Moreover, the S RNA IGR of CaCV-Hainan was inserted with two stretches of 10- and 20-nt sequences of an unknown origin. The S RNA IGR of CaCV-Ph from Taiwan and CaCV-NRA from Thailand also derived from the CaCV-Qld-3432 through deletion of 218-nt sequences. Our findings provide valuable new insight into the structural variations and evolutionary origin of CaCV IGRs.

Tomato spotted wilt virus (TSWV) is well established in most countries worldwide, while it is rarely reported in China. In this report, we have determined the complete nucleotide sequence of a TSWV isolate named TSWV-YN infecting tomato in Yunnan province in southwestern China. The tripartite genome of TSWV-YN was found to consist of L, M and S RNAs of 8910, 4773 and 2970 nt, respectively. The complete genome sequence and the sequence of each genomic region of TSWV-YN from China were compared to those of four other TSWV isolates from Brazil and Korea. The phylogenetic relationship of the Chinese TSWV-YN isolate to other TSWV isolates of different geographic origin, based on the nucleotide sequences of the glycoprotein (GP) and nucleocapsid (N) genes, was also analyzed in this study.