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First Reports of Eggplant Mottled Dwarf Rhabdovirus in Cucumber and in Pepper. P. Roggero, Istituto di Fitovirologia applicata, C.N.R., Str. delle Cacce 73, I-I0I35 Torino, Italy. R. G. Milne, V. Masenga, and P. Ogliara, Istituto di Fitovirologia applicata, C.N.R., Str. delle Cacce 73, I-I0I35 Torino, Italy, and V. M. Stravato, Peto Italiana, Centro Ricerche di Latina, 1-04010, B.go Sabotino, Latina, Italy. Plant Dis. 79:321. Accepted for publication 20 January 1995. Copyright 1995 The American Phytopathological Society. DOI: 10.1094/PD-79-0321C.

Eggplant mottled dwarf rhabdovirus (EMDV), is endemic in eggplant, tomato, caper, honeysuckle, and Pittosporum tobira in the Mediterranean area (1,2). EMDV has no known vector In September 1993, unusual symptoms of vein yellowing, leaf curling, and reduced growth were observed on a few cucumber plants grown under plastic at Fondi (central Italy) where EMDV is quite common in eggplant, tomato, and P. tobira. The virus was transmitted from cucumber to several test plant species by mechanical inoculation: Gomphrena globosa, Vicia faha (local lesions), Capsicum annuum, Datura stramonium. Lycopersicon esculentum, Nicotiana clevelandii, N. glutinosa, N. rustica, N. tabacum, Solanum melongena, Chenopodium amaranticolor, C. quinoa, Brassica sinensis, Raphanus sativus, Cucumis melo, Cucurbita pepo, Ocymum basilicum (systemic hosts). The following species were not infected: Lactuca sativa, Citrullus lanatus, Phaseolus vulgaris, Vigna sinensis. In most test hosts, symptoms appeared 1 mo postinoculation, whereas local lesions appeared on Gomphrena globosa 10 days after inoculation. EMDV was identified by electron microscopy of negatively stained crude extracts, and by serology using an antiserum (As-0136) against the type isolate (EMDV-PV-0031).The above antiserum and respective virus were obtained from the Deutsche Sammlung von Mikroorganismen (DSM). Double diffusion and Western blot serology tests revealed no differences between this cucumber isolate and EMDV-PV-0031. Also, the host range of this isolate was similar to that of EMDV. Field symptoms were reproduced by mechanical inoculation of cucumber. In September 1994, severe symptoms were observed on a few pepper plants grown under glass in Albenga (NW Italy). Apical leaves showed vein yellowing and chlorosis, and fruits had a warty and mottled appearance. The infected plants were always close to glasshouse openings, suggesting that the virus had been introduced from outside by a vector. Electron microscopy (thin sectioning and negative staining) of field samples revealed the presence of very large numbers of bacilliform particles. The virus was serologically identified as EMDV, and had the same host range as that of the cucumber EMDV isolate. Field symptoms were reproduced on pepper by mechanical inoculation. In the naturally infected cucumber and pepper plants EMDV occurred alone, as we failed to detect any other viruses either by electron microscopy or mechanical inoculation of various experimental host species.

References: (I) G Adam et al. Phytopalhol. Z 120:31, 1987. (2) G. P. Martelli and M. Russo. Descrip. Plant Viruses No. 115, CM.I./A.A.B. 1973.