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Salinity is one of the oldest and most serious environmental problems in the world. The increasingly widespread salinization of soils and water resources represents a growing threat to agriculture around the world. A strategy to cope with this problem is to cultivate salt-tolerant crops and, therefore, it is necessary to identify plant species that are naturally adapted to high-salinity conditions. In this review, we focus our attention on some plant species that can be considered among the most representative halophytes of the Mediterranean region; they can be potential resources, such as new or relatively new vegetable crops, to produce raw or minimally processed (or ready-to-eat) products, considering their nutritional properties and nutraceuticals. The main biological and agronomic characteristics of these species and the potential health risks due to mycotoxigenic fungi have been analyzed and summarized in a dedicated section. The objective of this review is to illustrate the main biological and agronomical characteristics of the most common halophytic species in the Mediterranean area, which could expand the range of leafy vegetables on the market.

Diaporthe helianthi is the causal agent of sunflower stem canker, a serious pathogen of sunflower in Europe but recorded sporadically in Italy. The genetic diversity of D. helianthi isolates from different geographic origins (Argentina, France, Italy, Yugoslavia, Romania) was investigated using IGS sequences. A 400 bp fragment of the portion of the IGS region flanking the 5' end of the 18S gene was amplified from each isolate. The aligned nucleotide sequences showed intraspecific sequence homology from 99-100% among French/Yugoslavian isolates to 95-100% among Italian isolates. French/Yugoslavian isolates shared 90-92% sequence homology with Italian isolates. The phylogenetic tree obtained from the aligned data revealed three separate groups. Group 1 included all isolates from France and former Yugoslavia and one isolate from Argentina; Group 2 included all Italian isolates and one isolate from Argentina. The most distantly related isolate was that from Romania (Group 3). The average genetic distances among isolates within Group 1 and within Group 2 were 0.22 and 3.29 respectively. The analysis showed that all isolates originating from countries where severe outbreaks of the disease are reported annually (France and former Yugoslavia) form a well defined taxon characterized by relatively low variability. This group is distinct from the group formed by isolates originating from Italy, whose variability is relatively much higher. Results obtained revealed a marked differentiation among pathogen isolates, and members of Group 1 seem not yet to have spread into Italian sunflower-growing areas.

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Isolations of onygenalean fungi were made recently from different dung samples from Italy. A striking snowwhite species with gymnothecial ascomata, developed in damp chamber on dormouse dung collected in a cave, was subjected to keratinolytic tests and morphological, cultural, and phylogenetic studies. The keratinolytic ability of this species, associated with a Chrysosporium anamorph and a sexual state of appendiculate reticuloperidia and oblate ascospores, allows it to be accomodated in Onygenaceae. White ascomata, blunt or subcapitate peridial appendages, pitted ascospores, and tuberculate conidia suggest it to be a new Neogymnomyces, and this was confirmed by parsimony analyses of LSU and ITS nrDNA sequences. Following recent phylogenetic analyses, the morphological and physiological features of order Onygenales and its families are re– examined and discussed. After the introduction of a new species, Neogymnomyces is reviewed and compared with all other genera in Onygenaceae. The Chrysosporium imperfect state of Neogymnomyces virgineus is described and compared to the anamorph of N. demonbreunii. It is also compared to the atypical Chrysosporium merdarium and to several other Chrysosporium species with echinulate to verrucose–tuberculate conidia, isolated from guano, dung, and nitrogen–rich soils in caves. The onygenalean fungi isolated from any kind of dung are discussed and their facultative coprophily ascribed to variable faecal contents of keratin or other degradable substances. A key to the families and genera of the Onygenales is provided