Passiflora chlorotic spots a disease caused by a strain of bean yellow mosaic virus in passiflora coerulea in Italy

In spring 2000, chlorotic spots and light mottling were observed in the leaves of a blue passionflower plant (Passiflora caerulea, family Passifloraceae), growing in a private garden of Napoli (southern Italy). Electron microscope observations of leaf dips from naturally infected plant showed a virus with filamentous particles ca 750 nm in length. This virus was readily transmitted by inoculation of sap to a range of herbaceous hosts and to healthy seedlings of Passiflora caerulea, reproducing the field syndrome. The virus was identified as an isolate of Bean yellow mosaic virus (BYMV) by biological and serological tests. The experimental host range was comparable to that described for BYMV (Bos, 1970) while, in agar gel SDS-immunodiffusion tests, crude sap from naturally infected plant formed clear precipitin lines with an antiserum to BYMV (kindly supplied by V. Lisa, IVV-CNR, Turin). The same antiserum clearly decorated virus particles from leaf dips. BYMV has been previously reported from Passiflora caerulea, in mixed infection with Cucumber mosaic virus (CMV), in Croatia (Plese and Wrischer, 1984). This is the first record of BYMV infection in Passiflora caerulea in Italy.