Fourth International Bemisia Workshop International Whitefly Genomics Workshop
Symptoms and Complete Nucleotide Sequence Analysis of Sweet Potato Leaf Curl Virus Transmitted by Bemisia tabaci
1 Department of Agricultural Biology, NIAST, RDA, Suwon, Republic of Korea. Correspondence: hschoi@rda.go.kr
2 Mokpo Experiment Station, NICS, RDA, Mokpo, Republic of Korea
Sweet potato leaf curl virus (SPLCV) is a member of the genus Begomovirus of the family Geminiviridae, and is transmitted by Bemisia tabaci in a persistent manner. A sweet potato disease in Korea causing leaf curl symptom was identified as SPLCV based on biological, cytopathological, and molecular properties. The isolate could be detected in and transmitted by Bemisia tabaci Q biotype which recently appeared in Korea, but not by mechanical inoculation. Ribbon-like and rectangular inclusions were shown in the nuclei of infected plant cells. The complete nucleotide sequence was determined using 5 overlapping PCR clones from nine isolates. These isolates were similar in genome organization to SPLCV-US including six open reading frames (ORFs). The nine isolates could be divided into two groups based on genomic sequence identity. Their identity indices of intragroup and intergroups showed 100% and 97%, respectively. The relationships between these isolates and SPLCV-US were determined using phylogeny of the derived AV1, AV2, AC1, AC2, AC3, and AC4 amino acid sequences. The results indicate that all of the isolates might have evolved from a common ancestor possibly from the old world.