Plectosphaerella cucumerina, most frequently encountered in its Plectosporium state, is well known as a pathogen of several plant species causing fruit, root and collar rot, and collapse. It is considered to pose a serious threat to melon (Cucumis melo) production in Italy. In the present study, an intensive sampling of diseased cucurbits as well as tomato and bell pepper was done and the fungal pathogens present on them were isolated. Phylogenetic relationships of the isolates were determined through a study of ribosomal RNA gene sequences (ITS cluster and D1/D2 domain of the 28S rRNA gene). Combining morphological, culture and molecular data, six species were distinguished. One of these (Pa. cucumerina) is already known. Four new species are described as Plectosphaerella citrullae, Pa. pauciseptata, Pa. plurivora and Pa. ramiseptata. Acremonium cucurbitacearum is shown to be a synonym of Nodulisporium melonis and is transferred to Plectosphaerella as Plectosphaerella melonis comb. nov. A further three known species of Plectosporium are recombined in Plectosphaerella.

Since 2005, pitch canker symptoms have been observed in Apulia (southern Italy, 41°27′42.84″N, 15°33′0.36″E) on numerous trees of Pinus halepensis and P. pinea in urban parks and gardens. Trees showed crown decline as a consequence of dieback of twigs and branches and withering of needles. Bleeding cankers with abundant resin were visible on twigs and branches. The needles of affected twigs and branches wilted, faded, turned yellow, then red, and were discarded. Isolations from symptomatic needles, twigs, and branches were performed on water agar, potato dextrose agar (PDA), and pentachloronitrobenzene medium. A species of Fusarium was consistently isolated from all infected tissues, and pure cultures were obtained by single hyphal tip transfers on PDA and synthetic nutrient agar medium (2). Colonies were incubated at 22 ± 3°C for 7 to 10 days. They produced white aerial mycelia, violet pigment, typically 3-septate macroconidia with slightly curved walls, single-celled microconidia, and characteristic sterile hyphal coils. Microconidia were ovoid or allantoid and born in false heads on aerial polyphialides. The species was identified as Fusarium circinatum Nirenberg & O'Donnell (= F. subglutinans Wollenweb & Reinking) on the basis of morphological and cultural characteristics (3). The identification was confirmed by PCR with specific primers CIRC1A/CIRC4A. The specific primer pair amplified a 360-bp DNA fragment of the two nuclear ribosomal IGS region (4). The pathogenicity of three Italian isolates of F. circinatum from Pinus spp. (Fc1640, Fc1642, and Fc1643 stored in the collection of Dipartimento Scienze Agroambientali, Chimica and Difesa Vegetale, University of Foggia) was evaluated by artificial inoculations on 2-year-old potted seedlings of P. halepensis, P. pinea, P. nigra, P. sylvestris, P. domestica, P. pinaster, P. excelsa, P. radiate, and Pseudotsuga menziesii (10 seedlings for each species and fungal isolate). Small PDA plugs from actively growing colonies of F. circinatum were introduced into a U-shaped cut on the stem of the seedlings and wrapped with moist sterile cottonwool. An equal number of control plants of each Pinus spp. was inoculated with sterile agar. All plants were grown in a nursery at ambient temperature (20 to 28°C). Within 30 days after inoculation, resinous cankers appeared on the stem of the seedlings of P. halepensis, P. pinea, P. domestica, P. pinaster, and P. radiata. Basal needles began to wilt, turn yellow, then red, and were discarded. F. circinatum was reisolated from stems of symptomatic seedlings. No symptoms were observed on seedlings of Pseudotsuga menziesii, P. sylvestris, P. excelsa, and P. nigra or on control seedlings. In Europe, pitch canker caused by F. circinatum previously has been reported only in Spain on P. radiata and P. pinaster (1). There was an unconfirmed report of this disease in Italy ( http://www.eppo.org ), but to our knowledge, this is the first definite conclusive evidence of the presence of pitch canker of pine in Italy. References: (1) E. Landeras et al. Plant Dis. 89:1015, 2005. (2) H. I. Niremberg. Mitt. Biol. Bundesanst. Land-Forstwirtsch. Berl.-Dahl, 169:1, 1976. (3) H. I. Niremberg and K. O'Donnell. Mycologia 90:434, 1998. (4) W. Schweigkofler et al. Appl. Environ. Microbiol. 70:3512, 2004.

Six Phaeoacremonium species (spp.) were isolated from symptomatic wood of olive trees (Olea europea) in Apulia (southern Italy) that showed crown wilt and twig and branch dieback. These Phaeoacremonium spp. were identified according to their morphological characteristics and by analyses of partial sequences of the actin and β-tubulin genes. Combining these cultural, morphological and molecular data, three Phaeoacremonium spp. were isolated that are already known to be responsible for severe decline of olive in Apulia, Phaeoacremonium aleophilum, Phaeoacremonium al vesii and Phaeoacremonium parasiticum, together with three other Phaeoacremonium spp. that are associated for the first time with wilt, decline and dieback of olive orchards in Italy and worldwide: Phaeoacremonium italicum, Phaeoacremonium sicilianum and Phaeoacremonium scolyti. To understand and to confirm their involvement in wilt and decline of olive trees, pathogenicity assays were performed on shoots of young olive plants. The data indicate that all six of these Phaeoacremonium spp. can cause discolouration, necrotic wood, and death of shoots, although different levels of virulence were observed, with Pm. italicum, Pm. aleophilum and Pm. sicilianum producing greater necrotic lesions than the other Phaeoacremonium spp. investigated here.

This study was carried out in 2012 at Stornarella (Italy; 41° 15'29" N; 15° 43'56" E; 154 m a.s.l.). We investigated the effects of reuse of secondary treated agro-industrial wastewater for irrigation, in comparison with conventional groundwater, and we monitored soil chemical characteristics and fungal populations during the crop cycle of processing tomato (Solanum lycopersicum L.). Compared to the groundwater, the wastewater had significantly higher electrical conductivity, total suspended solids, sodium, calcium, magnesium, potassium, sodium adsorption ratio, chemical oxygen demand, biological oxygen demand over five days, ammoniumnitrogen, phenols, bicarbonates, phosphates, sulphates and chlorides. Most of these parameters were significantly greater also in the wastewater-irrigated soil. During the tomato crop cycle, there were significant shifts in the structure of the soil microfungal community. Saprophytic species increased in the wastewater-treated soil, while phytopathogens such as Fusarium oxysporum progressively decreased. More investigations into the mechanisms by which wastewater acts on disease suppression is needed to make the use of such wastewaters more predictable. The irrigation water source did not significantly affect the qualitative traits of the crop yield. For both irrigation treatments, the most important qualitative parameters that characterized the processing tomato fruit (i.e., dry matter content, pH, soluble solid content, colour parameters) were in agreement with reports in the literature.

Botryosphaeriaceae spp. have a cosmopolitan distribution and a wide range of plant hosts. Over the last 15 years, worldwide, 21 species of this family have been associated with grapevine trunk diseases that cause cankers and dieback on grapevines. Here, we surveyed vineyards of Vitis vinifera ‘Lambrusco’, ‘Sangiovese’, and ‘Montepulciano’ in three areas of the Foggia province (Cerignola, Foggia, and San Severo) in southern Italy. Wood samples from grapevines showing general decline, dieback, cankers, and wood and foliar discoloration yielded 344 fungal isolates identified as Botryosphaeriaceae spp. A phylogenetic study combining internal transcribed spacer and translation elongation factor 1-α sequences of 60 representative isolates identified nine botryosphaeriaceous species: Botryosphaeria dothidea, Diplodia corticola, D. mutila, D. seriata, Dothiorella iberica, Do. sarmentorum, Lasiodiplodia citricola, L. theobromae, and Neofusicoccum parvum. Pathogenicity tests confirmed that all nine species cause canker and dieback of grapevines. However, this is the first report of L. citricola as causal agent of wood cankers and dieback of grapevine. To date, including L. citricola, there are 25 botryosphaeriaceous species associated with V. vinifera worldwide, of which 12 have been reported for grapevines in Italy.