SEED TRANSMISSION OF FIG LATENT VIRUS 1

The transmission through seeds of Fig latent virus 1 (FLV-1), a putative member of the genus Trichovirus, was investigated. Batches of seedlings of different age (1-yearold and 4-weeks-old) and geographical origin (Italy, Greece and Turkey) were analyzed by immunosorbent electron microscopy (ISEM) using a virus-specific antiserum. FLV-1 was detected in all groups of seedlings, the great majority of which were symptomless. Infection rate ranged from 73 to 100% (average 92%). Bundles of virus particles were observed in the cytoplasm of mesophyll cells of symptomless seedlings and positive RT-PCR responses were obtained in a few random assays using FLV- 1-specific primers. The high transmission rate differentiates FLV-1 from most of the other seed-transmitted plant viruses which, in general, have a lower transmission frequency, and from the extant trichoviruses, none of which is apparently transmitted though seeds.