Abstract
Serological property and electrophoretic mobility of coat protein as well as symptoms on citrus and herbaceous plants were compared on two isolates (S-58, MIE-88) of satsuma dwarf virus (SDV) and four of related viruses (Ci-968, LB-1, Az-1, NI-1), using enzyme-linked immunosorbent assay (DAS-ELISA), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and electro-blot immunoassay. Symptoms on citrus and herbaceous plants showed that S-58 and MIE-88 are SDV, Ci-968 is citrus mosaic virus (CiMV), NI-1 is navel orange infectious mottling virus (NIMV), while LB-1 and Az-1 are unreported viruses. In DAS-ELISA, S-58 and MIE-88 reacted strongly to anti-S-58 polyclonal antibody (S-PA), Ci-968 and LB-1 strongly to anti-Ci-968 antibody (Ci-PA) while Az-1 and NI-1 reacted to neither of them. SDS-PAGE revealed that S-58 and MIE-88 had two major coat proteins of about 42, 000 and 22, 000 daltons (slow migrating band, SB and fast migrating band, FB), Ci-968, LB-1 and Az-1 had ones of about 42, 000 and 23, 000 daltons, and NI-1 had ones of about 42, 000 and 22, 500 daltons. In electro-blot immunoassay, S-PA reacted strongly to SB of S-58 and MIE-88, Ci-PA reacted strongly to SB of Ci-968, LB-1 and Az-1, and relatively weakly to SB of S-58 and MIE-88, while neither of S-PA and Ci-PA reacted to SB of NI-1. FB of S-58 and MIE-88 reacted very weakly to S-PA and Ci-PA. FB of Ci-968, LB-1, Az-1 and NI-1 reacted to neither of S-PA and Ci-PA. These results show that the six isolates can be classified as follows; SDV group (S-58 and MIE-88), CiMV group (Ci-968, LB-1 and Az-1) and NIMV group (NI-1). However, it was considered that more data should be accumulated to define these groups as distinct viruses or strains of SDV.
