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Virus-free and artichoke latent virus (ALV) infected plants of ‘Brindisino’ artichoke obtained by in vitro propagation, were studied over a period of three years to evaluate the effect of ALV infection on artichoke field performance and to determine the infection rate of healthy plants. ALV infection caused qualitative and quantitative changes ‘Brindisino’ artichoke such as leaf and bract discoloration, opening of head apex, delay of first harvest, shortening of head stalk, reduction of head width and a dramatic decrease of yield. Due to the high infection rate of healthy plants during the trial period, the differences in the production of heads between the two groups of plants decreased in the last year of experiment.

Money plant or annual honesty (Lunaria annua L.) is an ornamental landscape plant used in flower beds and borders and also in flower arrangements. It is a biennial plant with large, pointed, oval leaves. Plants of L. annua showing white-to-cream, blister-like lesions on leaves and siliques (2) were found in private gardens where approximately 800 plants of 1,000 (approximately 80 to 90%) that were observed showed symptoms. The disease was also found in two ornamental nurseries, although it was limited to a few mother plants because of extensive fungicide treatments. The gardens and ornamental nurseries were located in Potenza Province (Basilicata Region, southern Italy). Sporangiophores were mostly straight or arched and almost cylindrical with attenuated base and flat or rounded apex and measured 29.2 to 33.4 × 12.8 to 13.4 μm. Sporangia, produced in chains and joined by short connectives, exhibited a spherical or angular shape, were subhyaline, contained vacuoles, and had average maximum and minimum diameters ranging from 15.8 to 18.8 and 14 to 16 μm, respectively. The morphological characteristics closely resembled those reported for Albugo candida (Pers.) Kuntze (3). Sori were collected from naturally and artificially inoculated tissues of L. annua, with the aid of a stereomicroscope, and used to extract genomic DNA via a DNeasy Plant Mini DNA extraction kit (Qiagen, Hilden, Germany) according to the manufacturer's directions. The extracted DNA was used as a template for amplification of the internal transcribed spacer (ITS) region of rDNA with primer pair ITS4/DC6 (1,4) and sequenced. One sequence, GenBank Accession No. GQ328846, matched several sequences of A. candida (Pers). Kuntze (e.g., GenBank Accession Nos. GQ328837, GQ328836, GQ328835, GQ328834, and AF271231), showing 98% identity. Pathogenicity tests were performed and repeated twice. Leaves of 10 healthy seedlings of L. annua were surface cleaned during several washings with distilled water and then spray inoculated with a suspension of 103 sporangia/ml of A. candida. Five healthy seedlings were spray inoculated with the same volume of sterile water and served as controls. Inoculated seedlings were maintained in a moist chamber for 48 h at 20°C before being moved to a shaded glasshouse at 16 to 24°C and 90% relative humidity. White rust symptoms, similar to those observed in natural conditions, appeared on leaves of inoculated seedlings 10 to 14 days later, demonstrating that A. candida was the causal agent of the disease. Control plants remained symptomless. White rust has been reported on L. annua in Europe (Czech Republic, Germany, Poland, and the United Kingdom) and in the northwestern United States (3). To our knowledge, this is the first report of A. candida infecting annual honesty plant in Italy. References: (1) P. Bonants et al. Eur. J. Plant Pathol. 103:345, 1997. (2) D. Choi et al. Mycotaxon 53:261, 1995. (3) D. A. Glawe et al. Online publication. doi:10.1094/PHP-2004-0317-01-HN. Plant Health Progress, 2004. (4) T. J. White et al. Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. In: PCR Protocols. A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.

An isolate of tomato black ring virus from artichoke (TBRV-A) was compared biologically, physico-chemically and serologically with three strains of the virus, i.e. TBRV-potato bouquet (TBRV-BU), TBRV-beet ringspot (TBRV-W), and TBRV-celery yellow vein (TBRV-Ce). Cytopathic effects of TBRV-A infection in C. quinoa and its relationships with two strains of artichoke Italian latent virus (AILV-S and AILV-G) were also investigated. Physical properties in vitro, sedimentation coefficients and molecular weight of protein subunits and nucleic acid species of TBRV-A were very similar to those known for TBRV. In serological tests, TBRV-A appeared more closely related to TBRV-W (SDI = 1) than to TBRV-Ce and TBRV-BU (SDI = 2–3). Finally, TBRV-A was very, distantly related to AILV-S and AILV-G (SDI = 11–12).

Cynara rhabdovirus (CyRV) was isolated from symptomless artichoke plants in southern Italy using Nicotiana langsdorffii as susceptible host and immune serum to artichoke latent virus to eliminate this virus from inoculum. CyRV can infect several solanaceous species, has thermal inactivation point of 40-45°C, dilution end point between 10−2 and 10−5 and longevity in vitro at 4 and 20°C of 4-5 days and 6-24 h, respectively. It was purified and used for preparing antisera with homologous titre varying from 1: 16 to 1: 64. In decoration tests, the virus did not react against antisera to eggplant mottled dwarf virus (EMDV) and its antiserum did not decorate ivy vein clearing virus (IVCV). Ultrastructural aspects of CyRV infection in Datura stramonium and Nicotiana glutinosa were very like those described for the same virus in the past except for presence of longer virions which were often encountered in infected cells during this study. Zusammenfassung Weitere Studien uber das Cynara rhabdo virus Cynara rhabdo virus (CyRV) wurde aus symptomfreien Artischockenpflanzen in Suditahen lsoiiert, wobei Nicotiana langsdorffu als Wirt und Antiserum gegen das artichoke latent virus zur Eliminierung dieses Virus aus dem Inoculum dienten. CyRV infiziert mehrere Solanaceen, hat einen thermakn lnaktivierungspunkt von 40—45°C, einen Verdlinnungsendpunkt von 10−2 bis 10−5, je nach Wirtspfianze, und erne Lebensdauer in vitro von 4–5 Tagen (4°C) bzw. 6–24 Stunden (20°C). CyRV wurde gereinigt und Antiseren mit homologen Titern von 1/16 bis 1/64 hergestellt, Bei immunelektronenmikroskopischen Tests reagierte CyRV nicht mit Antiseren gegen eggplant mottled dwarf virus (EMDV) und CyRV-Antiserum dekorierte nichl ivy vein clearing virus (IVCV). Die zyiopathologischen Effekte einer CyRV-Infektion in Datura stramonium und Nicotiana glutinosaahneln sehr denen, die fur dieses Virus fruher schon beschrieben wurden, jedoch wurden diesmal haufig langere Viruspartikeln gefunden.

Two raspberry ringspot virus variants, RRV-T and RRV-G, found in artichoke of Turkish and Greek origin, were compared biologically (indexing), biochemically and serologically to two strains of the same virus, RRV-S and RRV-E originating from Scotland and England, respectively. Molecular weight values of protein and nucleic acid of RRV-T and RRV-G were in good agreement with those already known for RRV. RRV-T and RRV-G appeared serologically very similar to each other (serological differentiation index = 1) and well distinguishable from RRV-S and RRV-E (serological differentiation indices varying between 3 and 6). Phaseolus vulgaris cv. La Victoire, Ocimum basilicum cv. Foglia di Lattuga, Cucumis sativus cv. Delicatezza, and Cucurbita pepo cv. Zucchetta striata d'ltalia seemed herbaceous hosts useful for differentiating each strain from the others on symptomatological basis.

A virus isolated from Anagyris foetida and infecting species in the Leguminosae and Solanaceae had typical properties of a tymovirus. It sedimented as two components (49 S and 103 S) and induced the formation of double membrane-bounded invaginations in the chloroplasts of infected cells. Large numbers of ‘empty shells’ were found in the nuclei. The coat protein had a molecular weight of c. 20.000 and the RNA consisted of c. 5500 nucleotides. Crystallization of the virus in laminal crystals could be achieved by precipitation with 10 % polyethylenglycol 6000 and 1 % NaCl. Serologically, the virus was closely related to Scrophularia mottle, Ononis yellow mosaic and Plantago mottle viruses. The four viruses which all infect leguminous hosts are separated by serological differentiation indices which are mostly between 1 and 3. It is therefore suggested that they all should be considered as strains of the same virus which for reasons of priority should have the name Scrophularia mottle virus (ScrMV). The proposed Anagyris strain clearly differs from the Scrophularia mottle, Ononis yellow mosaic and Plantago mottle strains of ScrMV in host range, symptomatology, electrophoretic mobility serological properties and some cytopathogenic effects. It is not clear why the Anagyris strain infects A. foetida systemically in nature, but only locally under greenhouse conditions. Zusammenfassung Charakterisierung eines Tymovirus-Isolates aus Aaagyris foetida als Stamm des Scrophuhria mottle virus Ein Virus, das aus Anagyris foetida isoliert worden war und das Pflanzenarten in den Familien der Leguminosen und Solanaceaen infiziert, zeigt typische Eigenschaften eines Tymovirus. Es hat zwei bei 49 S und 103 S sedimentierende Komponenten und fuhrt zur Bildung von Invaginationen mit doppelten Membranen in Chloroplasten. In infizierten Kernen werden, leere Hullen’ in groser Anzahl gefunden. Das Hullprotein hat ein Molekulargewicht von c. 20.000 und die RNA besteht aus c. 5500 Basen. Viruskristalle konnen aus teilgereinigten Praparaten durch Zugabe von 10 % Polyathylenglykol 6000 und 1 % NaCl erhaken werden. Serologisch ist das Virus eng mit dem Scrophularia mottle (ScrMV), Ononis yellow mosaic und Plantago mottle virus verwandt. Die serologischen Differenzierungsindizes liegen mit fast allen getesteten Seren zwischen 1 und 3. Es wird daher vorgeschlagen, alle diese Viren, die samtlich Leguminosen infizieren, als Stamme eines Virus anzusehen, das nach der Prioritatsregel ScrMV heisen sollte. Unser Anagyris-Stamm unterscheidet sich durch seinen Wirtspflanzenkreis, seine elektrophoretische Wanderung, seine serologischen Eigenschaften und einige zytopathogene Effekte von dem Scrophularia mottle, dem Ononis yellow mosaic und dem Plantago mottle Stamm des ScrMV. Bisher unklar ist, warum der Anagyris-Staxnm A. foetida nur unter naturlichen Bedingungen, nicht aber im Gewachshaus systemisch infiziert.

SUMMARY An isolate of artichoke latent virus (ALV-I) obtained from a symptomless artichoke plant in Southern Italy was characterised and compared with ALV isolates from other countries. ALV occurs in California and throughout the western part of the Mediterranean basin but of Mediterranean countries east of Italy, it was found only in Israel and Turkey. ALV-I was readily transmissible by inoculation of sap to a moderate range of hosts, was transmitted in a non-persistent manner by Aphis fabae, Brachicaudus cardui and Myzus persicae, but was not seed transmitted. The virus has flexuous rod-shaped particles measuring c. 12 nm × 746 nm with a sedimentation coefficient of 145 S and a buoyant density of 1·31 g/cm3. The particles contain single stranded RNA with a mol. wt of 3 × 106 and protein composed of a single polypeptide species with a mol. wt of 33 000. Cylindrical cytoplasmic inclusions consisting of pinwheels and laminated aggregates were present in cells of naturally and artificially infected plants. ALV isolates from different geographical origin were indistinguishable from ALV-I biologically, morphologically, serologically and ultrastructurally. These properties place ALV in the Potyvirus group, but it was serologically unrelated to 12 other potyviruses 10 of which occur commonly in Italy.

SUMMARY The biological, serological and physico-chemical properties of one isolate of artichoke yellow ringspot virus (AYRV) from Greece and another from Italy were compared. Both isolates infected 56 herbaceous species and there were few differences between them in the symptoms they caused. During purification they behaved identically and both tended to aggregate. Virus particles were isometric and measured c. 30 nm in diameter. In CsCl, virus sedimented as mixed aggregates of empty and full particles with buoyant densities varying from 1.20–1.30 g/ml and from 1.40–1.53 g/ml, respectively. The coat protein of AYRV contains a single polypeptide of mol. wt 53000 and the genome consists of two species of single-stranded RNA with mol. wts 2.17 × 106 (RNA-1) and 1.85 × 106 (RNA-2) daltons, estimated under denaturing conditions. The two virus isolates are serologically very closely related but are unrelated to 28 other plant viruses with isometric particles. The characteristics of AYRV suggest that it is a possible member of the nepovirus group.

A virus with filamentous particles was isolated from symptomless plants of Cynara scolymus cvs Romanesco and Terom obtained by in vitro meristem culture in northern Italy. The virus was characterized biologically, physico-chemically and serologically. The cytopathology induced by its infection in two artificial hosts (Chenopodium quinoa and Nicotiana benthamiana) was also investigated. The virus has slightly flexuous elongated particles measuring 12 ± 664 nm; its sedimentation coefficient, RNA content, mol. wts. of RNA and coat protein subunits are 150 S, 6 %, 2.2 × 106 and 2.9 × 104, respectively. In microprecipitation tests, it resulted serologically related to poplar mosaic virus (PopMV) (SDI = 4–5). Cellular inclusions and cytopathology observed in both the artificial hosts conform to those of the carlavirus group.

Author(s): Calavan, E. C.; Blue, R. L.; Harjung, M. K.; Cartia, G.; Granett, A. L.; Rana, G. L.; Gumpf, D. J.

A survey was carried out to investigate the relative distribution of artichoke Italian latent virus (AILV) (1), and its nematode vector, Longidorus attenuatus Hooper, in Apulia, southern Italy. In this region artichoke is cultivated on about 15,000 ha in three major areas, viz. in the surroundings of Bari, where the crop was first established, and in the provinces of Brindisi and Foggia, where it spread subsequently. In these areas a total of over 180 fields of artichokes were inspected during autumn and winter, 1973–74. Soil samples from the rhizosphere of plants chosen at random (4–6/field) were checked for the presence of L. attenuatus and the leaves of the same plants were used for sapinoculating French bean, a suitable host for assaying AILV (2). The results of this survey show that AILV prevails in the Bari area, occurring in more than 70% of the sampled fields (Table 1). The virus is less widespread in Brindisi and Foggia provinces where it was recovered from 23 and 10% of the samples, respectively.

The natural resources are currently overexploited and since 1992 the Conference of Rio de Janeiro has focused on sustainable development to safeguard our planet for future generations. The Fungi kingdom includes producers of goods and services for ecosystems and organisms widely used in the food industry. Besides, macrofungi are recognized as nontimber forest products and could be utilized as agents of environmental management through weed biocontrol and environmental improvement. Moreover, the cultivation of fungi, in particular truffles, can provide an important income in agroecosystems, especially in marginal areas, along with the development of new technologies to produce novel products from fungi. © 2013 Societá Botanica Italiana.

Hypogeous fungi are common in arid and semi-arid areas of the Mediterranean basin and, in particular, they are found in Italy, Spain, northern African countries (especially in Morocco, Algeria, and Tunisia), and in the Middle East. These fungi and, in particular, some species belonging to the genus Tuber and the desert truffles (Terfezia spp. and Tirmania spp.) form ascomata of considerable economic value. In this review, a panorama of hypogeous fungal diversity and information on their ecology in Mediterranean arid and semi-arid ecosystems have been reported; their economical importance and cultivation potential are also underlined.