Three distinct groups of isolates of <Emphasis Type="Italic">Tomato yellow leaf curl virus</Emphasis> in Japan and construction of an infectious clone

Complete nucleotide sequences of eight Japanese isolates of Tomato yellow leaf curl virus (TYLCV) were determined and compared with four TYLCV isolates already reported. These isolates separated into three groups – Shizuoka (Sz), Aichi (Ai), Nagasaki (Ng) – and had 99% identities within the groups. Full-length molecules of DNA-A of group Sz consist of 2791nt and those of group Ai contain 2787nt. Both were closely related to TYLCV-Is.M, although those of group Ng had 2793nt and were more closely related to TYLCV-Is. Comparison of common sequences of isolates belonging to groups Sz and Ai had substitutions of 4nt in the intergenic region and nonsynonymous substitutions at open reading frames between the groups. None of the isolates tested had DNA molecules. Agroinfection of four plant species with a DNA-A dimeric infectious clone of TYLCV-SzY, a member of group Sz, resulted in systemic infection. Tomato plants then developed typical yellow leaf curl symptoms.The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession numbers AB116629, AB116630, AB116631, AB116632, AB116633, AB116634, AB116635, and AB116636