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Eggplant mottled dwarf virus (EMDV) was detected for the first time in southern Italy in several Hibiscus rosa-sinensis L. plants with vein yellowing. The virus was identified by the reactions of a herbaceous host range, cytopathology and serology. Virions were observed only in the nuclei of infected ceiis where they accumulated between the inner and outer lamella of the nuclear envelope. The virus was identified by an antiserum to a potato isolate of EMDV both in immunoelectron microscopy tests and in leaf sap with indirect ELISA. A limited survey revealed that EMDV occurs in naturaily infected hibiscus in Campania, Calabria and Sicily (southern Italy). Some aspects of the epidemiology of EMDV are briefly discussed.

Dal punto di vista fitosanitario la coltura nell' Agro Pontino non presenta particolari pro-blematiche. Solo le poopolazioni del ragnetto rosso Tetranychus urticae Koch raggiungono frequentemente livelli di dannosità economica, tali da richiedere specifici interventi acaricidi. Negli ultimi 6-7 anni però si è assistitoa un progressivo declino della produttività della coltura a causa della comparsa prima sporadica e poi estremamente diffusa di piante con stentata vegetazione e con ingiallimenti fogliari generalizzati. In alcuni appezzamenti ispezionati la percentuale di piante con sintomi fogliariè risultata intorno al 50-60%, associata a una riduzione dei tuberi commerciabili fino al 50%. Si è ritenuto di investigare in maniera più approfondita, allo scopo di identificare l'agente/i responsabili della sin- drome osservata in molte coltivazioni della provincia di Latina e per arrivare a definire possibili strategie di controllo della malattia.

During spring 2005, symptoms of a disease consisting of striking coalescent yellow spots, pale mosaic and slight deformations of the leaves were observed on the canopy of some plants of Passiflora edulis Sims. (family Passifloraceae, commonly known as "purple passion fruit" or "granadilla", growing in a garden of the Naples area (southern Italy). The same plants showed pale coloration of the flowers whereas fruits were apparently normal. In summer, symptoms on the new vegetation became milder. Uranyl acetate stained leaf-dip preparations observed under the electron microscope showed isometric virus particles ca. 30 nm in diameter.

In spring 2002, plants of H. macrophylla showing yellowish spots especially on the old leaves were observed in some greenhouses of Apulia (southern Italy). A virus with filamentous particles ~490 nm in length was isolated from symptomatic leaves of Hydrangea plants by mechanical inoculation to herbaceous hosts. A fragment of 735 nt of the viral genome was sequenced. Based on the homology found, the virus was identified as an isolate of Hydrangea ring spot virus (HRSV). This paper reports the results of the partial molecular characterization of the HRSV isolate identified in Hydrangea plants in Apulia. This is the first molecular characterization of an isolate of HRSV from Italy. The importance of a phytosanitary improvement of nursery-gardening production is briefly discussed.

no. spécial; International audience; Among plant viruses, Tomato spotted wilt virus (TSWV) is considered as the most widespread and to have the largest host-range. This virus is responsible for numerous epidemics in different regions of the world, mainly in horticultural and floral crops, which are often destructive and cause heavy economic losses. The highly polyphagous na- ture, the efficiency of virus transmission and the biological activity of its vectors, the rapidity with which new variants arise, and difficulties in the control of the vectors, make TSWV one of the most feared plant viruses by growers of agricultural crops. Preventive and integrated cultural practices such as the eradication of weed hosts able to serve as virus reservoirs, combined with vector management strategies, play a crucial role in the control of the virus. Thus, the availability of an up-to-date list of TSWV host plants is a potentially useful reference for researchers and farmers.The current list of TSWV hosts consists of 1090 plants species belonging in 15 families of monocotyledonous plants, 69 families of dicotyledonous plants and one family of pteridophytes.

Among plant viruses, Tomato spotted wilt virus (TSWV) is considered as the most widespread and to have the largest host-range. This virus is responsible for numerous epidemics in different regions of the world, mainly in horticultural and floral crops, which are often destructive and cause heavy economic losses. The highly polyphagous na- ture, the efficiency of virus transmission and the biological activity of its vectors, the rapidity with which new variants arise, and difficulties in the control of the vectors, make TSWV one of the most feared plant viruses by growers of agricultural crops. Preventive and integrated cultural practices such as the eradication of weed hosts able to serve as virus reservoirs, combined with vector management strategies, play a crucial role in the control of the virus. Thus, the availability of an up-to-date list of TSWV host plants is a potentially useful reference for researchers and farmers.The current list of TSWV hosts consists of 1090 plants species belonging in 15 families of monocotyledonous plants, 69 families of dicotyledonous plants and one family of pteridophytes.

Among plant viruses, Tomato spotted wilt virus (TSWV) is considered as the most widespread and to have the largest host-range. This virus is responsible for numerous epidemics in different regions of the world, mainly in horticultural and floral crops, which are often destructive and cause heavy economic losses. The highly polyphagous nature, the efficiency of virus transmission and the biological activity of its vectors, the rapidity with which new variants arise, and difficulties in the control of the vectors, make TSWV one of the most feared plant viruses by growers of agricultural crops. Preventive and integrated cultural practices such as the eradication of weed hosts able to serve as virus reservoirs, combined with vector management strategies, play a crucial role in the control of the virus. Thus, the availability of an up-to-date list of TSWV host plants is a potentially useful reference for researchers and farmers. The current list of TSWV hosts consists of 1090 plants species belonging in 15 families of monocotyledonous plants, 69 families of dicotyledonous plants and one family of pteridophytes.

Tobacco mild green mosaic virus (TMGMV; genus Tobamovirus) occurs probably in all tropical and subtropical regions where Nicotiana glauca (tobacco tree) is distribuited (North America, Australia, many European and African countries, Canary and Mediterranean islands). In Italy, TMGMV has been reported in pepper in 1970. During spring 2003 several plants of N. glauca growing in south Italy (Naples), were found to be infected by a tobamo-like virus based on preliminary electron-microscope observation of leaf samples.

During 2001, in the Aegean Greek islands of Rodi and Kastellorizo, wild castor bean plants (Ricinus communis L.), showing yellowish vein netting and mottling of the leaves were observed. A virus was isolated by mechanical inoculation from such plants to herbaceous hosts, which based on biological, serological and molecular assays was identified as an isolate of Olive latent virus 2 (OLV-2/CB), virtually indistinguishable from the type strain. The field syndrome was experimentally reproduced in artificially inoculated castor bean seedlings and the virus reisolated, thus fulfilling Koch’s postulates. This is the first report of OLV-2 outside Italy in a natural host other than olive.

A fragment of the NSM gene of naturally occurring Tomato spotted wilt virus (TSWV) isolates recovered in Apulia (southern Italy) from different cultivated and wild plant species was amplified by RT-PCR. The resulting 670 bp amplicon was cloned, sequenced and compared with available NSM sequences of other tospoviruses. The primary nucleotide sequence was 94.3 to 100% identical in all the Apulian TSWV isolates and had a 94-99% identity with TSWV-BR01, TSWV-L3, TSWV-JP, TSWV-A and TSWV-D. With other tospoviruses, sequence identity was in the range of 81-83% with Tomato chlorotic spot virus and Chrysanthemum stem necrosis virus and, 74-79% with Groundnut ring spot virus, Zucchini lethal chlorosis virus and Impatiens necrotic spot virus, 53-55% with Iris yellow spot virus, Peanut bud necrosis virus and Watermelon silver mottle virus. The phylogenetic tree showed three primary branches departing from the bulk of all NSM sequences; all the TSWV sequences clustered in two subgroups, denoted A-like and D-like, clearly distinct from the other tospoviruses. The inclusion in a group of any of the Apulian isolates of TSWV was apparently not determined by the year, the place or the host from which they were recovered. The A-like isolates clustered with TSWV-A, an isolate that was able to overcome host and pathogen-mediated resistance in tomato whereas the remaining six isolates clustered with TSWV-D, an isolate that did not overcome these forms of resistance. A simple and rapid procedure based on RT-PCR followed by enzymatic digestion was developed to identify isolates of the two subgroups.